Nothing Special   »   [go: up one dir, main page]

WO2006056809A1 - Dispositifs de refroidissement electrocaloriques a semi-conducteurs et procedes associes - Google Patents

Dispositifs de refroidissement electrocaloriques a semi-conducteurs et procedes associes Download PDF

Info

Publication number
WO2006056809A1
WO2006056809A1 PCT/GB2005/050207 GB2005050207W WO2006056809A1 WO 2006056809 A1 WO2006056809 A1 WO 2006056809A1 GB 2005050207 W GB2005050207 W GB 2005050207W WO 2006056809 A1 WO2006056809 A1 WO 2006056809A1
Authority
WO
WIPO (PCT)
Prior art keywords
heat
switches
electrocaloric
sink
switch
Prior art date
Application number
PCT/GB2005/050207
Other languages
English (en)
Inventor
Neil Mathur
Alexandr Mishchenko
Original Assignee
Cambridge University Technical Services Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB0426230A external-priority patent/GB2420662A/en
Application filed by Cambridge University Technical Services Limited filed Critical Cambridge University Technical Services Limited
Publication of WO2006056809A1 publication Critical patent/WO2006056809A1/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B21/00—Machines, plants or systems, using electric or magnetic effects
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2321/00—Details of machines, plants or systems, using electric or magnetic effects
    • F25B2321/001—Details of machines, plants or systems, using electric or magnetic effects by using electro-caloric effects
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/15—Microelectro-mechanical devices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D19/00—Arrangement or mounting of refrigeration units with respect to devices or objects to be refrigerated, e.g. infrared detectors
    • F25D19/006—Thermal coupling structure or interface
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]

Definitions

  • the present invention relates to solid state electrocaloric cooling devices with heat switches, and to related methods of cooling.
  • eSectrocaloric cooling system comprised of a plurality of electrocaloric (EC) working elements (an example of one is depicted in Fig. 1 ) with a range of working temperatures covering a wide temperature interval was described in Y.V. Sinyavsky and V. M. Brodyansky. Ferroelectrics. 131: p. 321 , 1992. and A.E. Romanov, Ju.V. Sinyavskij, N. D. Pashkov, and G. E. Luganskij. "Method of cooling and device for realization of this method", SU Patent No 2075015, 1993.
  • the heat exchange between adjacent electrocaioric working elements as well as heat flow to the ambient and from the cooled body was organised with fluid and gas heat exchangers.
  • the prototype schematic is shown in Fig. 5.
  • the working elements were made of PbSco. 5 Tao. 5 O 3 with various thermal treatment so that their working temperatures were different. Variations of ECE versus temperature for different working elements are shown in Fig. 2.
  • the prototype comprised two blocks of working elements 1 and 2 (see Fig. 5), heat load 3, and heat sinks 4, The liquid heat exchanger was pumped through the system with a pump 5.
  • Four blocks of PST have been combined into a single shell. Each block had a sandwich type structure comprising a number of PST plates 20 x 10 x 0.3 mm 3 each.
  • Electrocaioric refrigeration systems for cryogenic temperature ranges are disclosed in L.W. Lawless. "Paraelectric refrigeration method and apparatus", US Patent No 3436924, 1969. and L.W. Lawless. "Closed- cycle electrocaioric refrigerator and method", US Patent No 3638440, 1972.
  • An electrocaioric refrigeration system comprising a number of working elements separated by passive unidirectional heat pipes was proposed in A. Basiulis and B. L. Robert. "Solid-state electrocaioric cooling system and method", US Patent No 4757688, 1986.
  • the proposed unidirectional heat pipes work by principle of unidirectional heat transfer accomplished by evaporation of a liquid heat carrier, e.g. N 2 in a cryogenic temperature range. However, such a process is slow and has a large inertia, which makes the realization of such a device difficult.
  • the invention provides a device for transferring heat from a heat source to a heat sink, the device comprising: at least two heat switches, a first to receive heat from the heat source, a second to pass heat to the heat sink; at least one electrocalohc element between two said heat switches and in thermal contact with said two heat switches; and a control input for controlling said at least two heat switches and said electroca ⁇ oric element to transfer heat from said source to said sink; and wherein one or both of said heat switches comprise a thermoelectric heat switch, tunnelling heat switch or an electromechanical heat switch.
  • the device for transferring heat from a heat source to a heat sink is a part of a cascaded system having a plurality of devices for transferring heat from a heat source to a heat sink. More preferably the device for transferring heat from a heat source to a heat sink it is a stacked cascaded system and comprises a parallel system.
  • the control input may comprise one or more eiectrical connections.
  • Preferred embodiments further comprise a controller to control said heat switches and said at least one electrocaloric element, the controller comprising control means for: cooling said electrocaloric element to a temperature of less than said source or equal to said source; turning said first heat switch on to transfer heat from said source to said electrocaloric element; turning said first heat switch off; warming said electrocaloric element to a temperature of greater than said sink or equal to said sink; turning said second heat switch on to transfer heat from said electrocaloric element to said sink; and turning said second heat switch off.
  • the invention provides a method of controlling a heat transfer device for transferring heat from a heat source to a heat sink, the heat transfer device comprising at least one electrocaloric element disposed between a pair of thermoelectric heat switches, a first switch being in thermal contact with said source and a second switch with said sink, the method comprising: cooling said electrocaloric element to a temperature of less than said source or equal to said source; turning said first heat switch on to transfer heat from said source to said electrocaloric element; turning said first heat switch off; warming said electrocaloric element to a temperature of greater than said sink or equal to said sink; turning said second heat switch on to transfer heat from said eiectrocaloric element to said sink; and turning said second heat switch off; and wherein turning said heat switches off comprises applying a voltage in a first, forward direction to said switches; and wherein turning said switches on comprises applying a voltage in a second, reverse direction to said forward direction to a said switch.
  • controller configured to implement this method.
  • the invention further provides processor control code to implement the above- described controllers and methods, in particular on a data carrier such as a disk, CD- or DVD-ROM, programmed memory such as read-only memory (Firmware), or on a data carrier such as an optical or electrical signal carrier.
  • Code (and/or data) to implement embodiments of the invention may comprise source, object or executable code in a conventional programming language (interpreted or compiled) such as C, or assembly code, code for setting up or controlling an ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array), or code for a hardware description language such as Verilog (Trade Mark) or VHDL (Very high speed integrated circuit Hardware Description Language).
  • thermoelectric heat switches are provided for switching from a heat conducting to a heat insulating state.
  • the thermoelectric switches are replaced by microelectromechanica! switches.
  • the thermoelectric switches can operate in passive heat conducting mode.
  • the switches can operate in active heat conducting mode, with the reverse current passed through the couples in the off heat conduction state.
  • electrocaloric elements can take the form of multilayer capacitors comprised of ferroelectric thin films.
  • the electrocaloric elements can be made from bulk materials.
  • Thermoelectric heat switches can be energized by a direct electrical coupling to a current source or by induction coupling.
  • Figure 1 Shows a schematic of an electrocaloric element.
  • Figure 2 Shows results of the electrocaloric effect measurement of four different samples of PbSco. 5 Tao. 5 O3 used in the prototype shown in Fig. 5.
  • the Curie point taken as the temperature of the maximum of ECE, can be moved, which allows a much wider temperature interval to be covered than with a single element.
  • Figure 4 Shows a thermoelectric couple.
  • Figure 5 Shows a schematic of an electrocaioric fridge prototype. Some characteristics of the prototype are shown in Fig. 6.
  • Figure 6 Shows experimental results obtained with the prototype shown in Figure 5.
  • FIG 7 Shows schematic design of one embodiment of the proposed cooling device comprising one electrocaloric element 200 and two heat switches 100 and 110. Electronic circuits that supply the electrocaloric element and heat switches are not shown here for the sake of clarity.
  • Figure 8 Shows schematic design of one embodiment of the proposed cooling device, a cascaded system comprising 2 electrocaSoric elements 200 and 210; 3 heat switches 100, 110 and 120; and electronic circuits that supply the eSectrocaioric elements and heat switches. The circuits are not shown here for the sake of clarity.
  • Figure 9 Shows the working cycles of the coo ⁇ ng sandwich shown in Figure 8.
  • Other embodiments of the proposed device e.g. cascaded devices comprising 4, 6, etc. electrocaloric elements
  • Heat exchange between 200 and 210 takes ⁇ seconds and between 200 and 10 ⁇ 210 and 20) - 2 ⁇ seconds.
  • stands for a polarisation of an electrocaloric element (either 200 or 210) that increases its temperature by ⁇ T via the electrocaloric effect and a blue label ⁇ T
  • Figure 10 Shows the schematic design of another embodiment of the proposed cooling device, a cascaded system comprising 4 electrocaloric elements 200, 210, 220 and 230; 5 heat switches 100, 110, 120, 130, and 140; and electronic circuits that supply the electrocaloric elements and heat switches.
  • the circuits are not shown here for the sake of clarity,
  • Figure 11 Shows an example thermodynamic cooling cycle of an electrocaloric element (e.g. 200, 210 in Fig. 8).
  • Figure 12 Shows an example design of a micromechanical heat switch which can be fabricated with a method presented in Fig. 13.
  • Figure 13 Shows microfabrication of a ladder micromechanical heat switch shown in Fig. 12.
  • Figure 14 Shows a schematic design of still another embodiment of the proposed cooling device, a cascaded system comprising 6 electrocaloric elements 200, 210, 220, 230, 240, and 250; 7 heat switches 100, 110, 120, 130, 140, 150, and 160; and electronic circuits that supply the electrocaloric elements and heat switches.
  • the circuits are not shown here for the sake of clarity.
  • FIG. 15 Shows results of an example calculation of an example cooling cycle of one embodiment of the device - the one comprising 2 electrocaloric elements, shown in Fig. 8.
  • the temperatures of the heat source 20 (T 20 ), EC elements 200, 210 [T 2O o, T 210 ), and the heat sink 10 [T 10 ) are shown.
  • the picture represents equilibrium - 600 cycles have been simulated before these curves are taken.
  • Four stages of a possible refrigeration cycle are highlighted (see Fig. 9).
  • Figure 16 Shows efficiency and cooling power of one embodiment of the device comprising 4 electrocaloric elements (shown in Fig. 10) versus heat conductivity of the switches, ⁇ is the time for heat exchange between any two electrocaloric elements (A.3).
  • the influence of the reverse current on the performance shown in Fig. 18 is calculated at the highlighted temperature differences: 3 K for a cascaded device comprising 2 electrocaloric elements, 6 K for a cascaded device comprising 4 electrocaloric elements, and 10 K for a cascaded device comprising 6 electrocaloric elements.
  • Figure 18 Shows the influence of the heat switches' reverse current on the performance of some embodiments of the cooling device: cascaded devices comprising 2, 4, and 6 electrocaloric elements.
  • the particular current values can be reduced by increasing the number of couples N and decreasing the geometrical factor G - a standard approach in design of thermoelectric devices. It should be understood that the values used in the catcuiations are not fixed.
  • Figure 19 Shows estimated efficiency of some embodiments of the proposed device: cascades comprising 2, 4, and 6 electrocaloric elements and a commercially available thermoelectric cooler.
  • the average temperature difference between the hot and the cold ends is about 6— -8 0 C for all curves.
  • Figure 21 Shows a schematic design of an embodiment of a parallel configured device for transferring heat from a heat source 20 to a heat sink 10.
  • the device comprises at least two heat switches 100 and 110, the former to receive heat from the heat source 20, the latter to pass heat to the heat sink 10; at least one electrocaloric (EC) element 200 between the heat switches 100 and 110 and in thermal contact with the heat switches; and a control input for controlling 100, 110, and 200.
  • One or both of the heat switches comprise a thermoelectric heat switch, tunnelling heat switch or an electromechanical heat switch.
  • a device described above is a part of a cascaded system having a plurality of the devices for transferring heat from a cold end to a hot end.
  • Some embodiments of a cascaded system are presented in Figs. 7, 9, and 13. Referring to Fig. 7, a cascaded system comprising two electrocaloric elements 200 and 210 and three heat switches 100, 110 and 120 is presented. An electrocaloric element 210 of an additional stage is utilised as a heat source in the previous stage of the cascaded system.
  • the embodiment of a cascaded system shown in Fig .8 comprises two cooling devices: a first device comprising an electrocaloric element 200 and heat switches 100 and 110 and a second device comprising an eiectrocaloric element 210 and heat switches 110 and 120.
  • Electrocaloric element 210 is utilised as a heat source in the previous stage comprising the electrocaloric element 200.
  • Electrocaloric element 220 is utilised as a heat source in the stage comprising electrocaloric elements 200 and 210.
  • Electrocaloric element 230 is utilised as a heat source in the stage comprising electrocaloric elements 200, 210, and 220.
  • the system comprises four cooling devices: a first device comprising an electrocaloric element 200 and heat switches 100 and 110, a second device comprising an eiectrocaloric element 210 and heat switches 110 and 120, a third device comprising an electrocaloric element 220 and heat switches 120 and 130, and a fourth device comprising an electrocaloric element 230 and heat switches 130 and 140.
  • the hot end of a fourth device is the cold end of the third device
  • the hot end of the third device is the cold end of the second device
  • the hot end of the second device is the cold end of the first device.
  • a cascaded system comprising six electrocaloric elements 200, 210, 220, 230, 240, and 250 and seven heat switches 100, 110, 120, 130, 140, 150, and 160 is presented. It should be understood that cascaded systems comprising any other number of electrocaloric elements and heat switches can be used.
  • a parallel configured device for transferring heat from a heat source 20 to a heat sink 10 is presented in Fig. 21.
  • a plurality of parallel positioned stacks 500, 510, 520 and 530 transfer heat from a heat source 20 to a heat sink 10.
  • the number of stacks can be different.
  • Each stage in each stack 500, 510, 520 and 530 comprises an electrocaloric cooling system presented in one or several embodiments of the present invention.
  • Other configurations and orientations of the elements shown in Fig. 21 may be used.
  • An off state of heat switches comprises applying a voltage in a first, forward direction to the switches, and an on state of the switches comprises applying a voltage in a second, reverse direction to the forward direction to the switches.
  • the heat switches do not need to fully reject heat in an off state.
  • Embodiments of a device of the present invention also comprise a control input that comprises one or more electrical connections, and means to control heat switches and electrocaloric elements (e.g. a computer program).
  • a method of controlling a heat transfer device for transferring heat from a heat source to a heat sink comprises: cooling electrocaloric element 200 to a temperature of less than source 20 or equal to the source 20; turning the first heat switch 110 on to transfer heat from the source 20 to the electrocaloric element 200; turning the first heat switch 110 off; warming the electrocaloric element 200 to a temperature of greater than the sink 10 or equal to the sink 10; turning the second heat switch 100 on to transfer heat from the electrocaloric element 200 to the sink 10; and turning the second heat switch 100 off.
  • Turning the heat switches 100 and 110 off comprises applying a voltage in a first, forward direction to the switches, and turning the switches 100 and 110 on comprises applying a voltage in a second, reverse direction to said forward direction to a said switch.
  • a device embodying aspects of the present invention also comprises a controller configured to implement methods explained above, and a carrier to carry a computer program code (e.g. host or disk) to implement methods explained above.
  • a controller configured to implement methods explained above
  • a carrier to carry a computer program code (e.g. host or disk) to implement methods explained above.
  • electrocaloric effect is, broadly speaking, a change of a material's temperature upon an application or removal of an electric field.
  • ECE electrocaloric effect
  • MCE magnetocaloric effect
  • FIG. 1 A standard geometry of an electrocaloric (EC) working element is shown in Fig. 1. It comprises a pair of electrodes 300 and a slab of electrocaloric material 310. So an electrocaloric element is basically a capacitor with an electrocaloric material between its electrodes. The element is energised from a DC or AC voltage source 330, and the voltage is applied by switching 320. So when the switch 320 is turned on, the electrocaloric material 310 polarises and its temperature changes due to the electrocaloric effect. When 320 is turned off, the temperature of 310 returns to its initial value. It should be understood that the Figure is a schematic only and different circuitry can be used, as well as different structure of the electrodes (e.g.
  • multilayer capacitor structure similar to that described in M. Togashi. "Multilayer ceramic electronic device", US Patent No 2003/0026059, 2003, for example; layers of electrocaloric material in the multilayer capacitor can be made with thin film deposition techniques, e.g. sol- gel, as disclosed in D.A. Barrow, T.E. Petroff, and M. Sayer. "Method for producing thick ceramic films by a sol gei coating process", US Patent No 5585136, 1996, for example).
  • the best known electrocaioric materials are perovskite ferroelectric materials.
  • the highest electrocaloric effect at room temperature was found in PbSco .5 Tao. 5 O 3 (PST).
  • PST PbSco .5 Tao. 5 O 3
  • the value of the ECE peaks at the critical temperature Tc but remains within 80% of the maximum value within about 10 0 C region around Tc.
  • the critical temperature can be adjusted by a special heat treatment of the material during the annealing phase of its manufacturing E. K, H. Birks, L.A.
  • a multilayer capacitor system comprised of a plurality of ferroelectric thin films (deposited by sol gel, for example, as disclosed in D.A. Barrow, T. E. Petroff, and M, Sayer. "Method for producing thick ceramic films by a sol gel coating process", US Patent No 5585136, 1996) separated with electrodes (with a geometry described in M. Togashi. "Multilayer ceramic electronic device", US Patent No 2003/0026059, 2003, for example) can manifest a much higher ECE than bulk material of the same composition due to the higher electric field applied.
  • the compounds described above can be used in embodiments of the invention either in the form of a multilayer capacitor or in bulk form. However, it should be understood, that any materials with ECE can be used in embodiments of the invention.
  • the inherent efficiency of an eiectrocaloric element depends on several factors. Among them are hysteresis losses if the materia! used is ferroelectric and losses due to Joule heating due to finite electrical resistance of the elements. As numerous experiments showed, the inherent efficiency of EC elements is remarkably high - around 98% of the Carnot cycle (Y.V. Sinyavsky, N. D. Pashkov, Y.M. Gorovoi, G. E. Lugansky, and Shebanov L. Ferroelectrics. 90: p. 213, 1980). The efficiency ⁇ was estimated using the formula:
  • a heat switch is a device that can be switched between two states - heat conducting and heat insulating.
  • the heat insulating state does not need to be fully insulating.
  • thermoelectric couple comprises two legs _ 440 ⁇ n-type semiconductor) and 450 ⁇ p-type semiconductor), several layers of electrical conducting material 410, several layers of material 400 which is an electrical insulator and heat conductor.
  • the element When the element is energised with the voltage source 460, it pumps heat from heat source 420 to heat sink 430.
  • the heat pumped at the cold surface 420 Q c (W) is equal to:
  • T Co id is the cold surface temperature (K)
  • ⁇ is the Seebeck coefficient (VK "1 )
  • / is the electrical current (A)
  • p is the resistivity of 440 and 450 ( ⁇ cm)
  • k is the heat conductivity of 440 and 450 (WcrrT 1 K *1 )
  • ⁇ T - the temperature difference between 430 and 420 (K)
  • G is the ratio of an element's cross-sectiona! area to its height (cm).
  • the first term in the brackets in (3) describes the Peltier effect
  • the second term describes Joule heating
  • the third describes parasitic heat flow from 430 to 420.
  • the value of I o ff can be found from the equation Qc - 0:
  • thermoelectric and microelectromechanical (MEMS) heat switches A magnetocaloric cooling system using thermoelectric and microelectromechanical (MEMS) heat switches is disclosed in U.S. Ghoshal. "Apparatus and methods for performing switching in magnetic refrigeration systems using thermoelectric switches", US Patent No 6595004, 2003.
  • Various arrangements of heat switches and working magnetocaloric elements are mentioned.
  • construction of such a device would be complicated.
  • efficiency and cooling power would be questionable due to large heat ieaks.
  • One of the significant differences between the device and method disclosed in U. S.6595004 and embodiments of the invention is the nature of the working elements - they are electrocaloric in embodiments of the invention, not magnetocaloric as in US6595004. This makes the whole system simpler and allows for direct estimations of the device efficiency with parameters of available materials.
  • thermoelectric heat switches were discussed in length in US6595004. All the discussion along with the conclusions are relevant in the present context. For people acquainted with the field it is well known that efficiency of a thermoelectric materia! sharply increases with decrease of the temperature difference between the hot and cold contacts of a thermocouple. This difference is kept small throughout the whole cooling cycle of the proposed device.
  • a piezoelectric heat switch is similar to the electrocaloric element shown in Fig. 1 , but material 310 has high piezoelectric effect in this case, i.e. significant contraction or elongation upon application of electric field. If placed between two electrocaloric elements so that upon elongation it touches both electrocaloric elements, and upon contraction touches none of them, such a piezoelectric element can work as a heat switch.
  • the proposed device does not use bulk piezoelectric heat switches.
  • microelectromechanical heat switches are used, but their major feature is a complex surface that increases the surface contact area, which is absent in V. M. Brodyansky, Yu.V. Sinyavsky, and N. D, Pashkov. "Thermal switch (its versions) 11 , SU Patent No 918770, 1982.
  • the device comprises at least one electrocaloric working element 200 placed between at least two heat switches 100 and 110, see Fig. 7.
  • Heat switches 100, 110 have thermal contact with a heat sink 10 and heat source 20 respectively. There is also a thermal contact between 100 and 200, 110 and 200.
  • a cascaded system comprising two electrocaloric working elements.
  • An electrocaloric element 210 of an additional stage is utilised as a heat source in the previous stage of the cascaded system, see Fig. 8.
  • the embodiment of a cascaded system shown in Fig.8 comprises two cooling devices: a first device comprising an electrocaloric element 200 and heat switches 100 and 110 and a second device comprising an electrocaloric element 210 and heat switches 110 and 120.
  • a heat source 20 is connected mechanically to the heat switch 120 so that there is a good thermal contact between them.
  • the heat switch 120 is mechanically connected to the working element 210, so that there is good thermal contact between them. However, there is no direct electrical connection between 120 and 210.
  • electrocaloric element 200 is thermally connected to heat switches 100 and 110 and electrically isolated from them. Elements 210 and 110 as well as 110 and 200 do not contact each other in Fig. 8 for the sake of clarity. Buffer layers providing thermal contact and electrical insulation between 10 and 100, 100 and 200, 200 and 110, 110 and 210, 210 and 120, and 120 and 20 are also not shown here for clarity.
  • thermoelectric elements can be used as heat switches, i.e. they can be switched between two states - heat insulating and heat conducting.
  • an on state corresponds to heat flow from the hot to the cold elements by virtue of heat conduction through the thermocouples in passive mode.
  • the heat flow in an on state is assisted by the application of a reversed current so that the time of heat exchange decreases, and this mode of operation is called active mode.
  • An off state is defined as zero or nearly zero heat transfer to the cold end of a thermoelectric couple/couples. In this state a direct current is passed through the couples so that the thermoelectric cooling effect precisely or almost precisely offsets the heat conduction.
  • the current passed through the thermocouples in an off mode can be higher than that required to offset the heat conduction process in order to reduce the time of heat exchange.
  • thermoelectric heat switch incorporated into the proposed device can be energised either directly or by electromagnetic induction, in a similar way to that described in U.S. Ghoshal. "Apparatus and methods for performing switching in magnetic refrigeration systems using thermoelectric switches", US Patent No 6595004, 2003 in relation to magnetocaloric systems.
  • thermoelectric switches are replaced by tunneling cooling devices, disclosed in A. Tavkhelidze, L. Koptonashvili, Z. Berishvili, and G. Skhiladze. "Method for making a diode device", US Patent No 6417060, 2002, for example. In these embodiments a proposed device operates in a similar way to that described in the previous paragraph.
  • thermoelectric heat switches can be manufactured by means of electrolysis disclosed in J.-P. Fleurial, M.A. Ryan, A. Borshchevsky, W. Phillips, E.A. Koiawa, G.J. Snyder, T. Caillat, T. Kascich, and P. Mueller.
  • Microfabricated thermoelectric power-generation devices US Patent No 6388185, 2002, incorporated by reference in its entirity.
  • the cited patent proposes a thermoelectric device for electrical energy generation, but it can be used for the reverse purpose, i.e. heat pumping, due to Onsager relations.
  • Thermocouples made by electrolysis are with a flat geometry, e.g.
  • thermoelectric materials with 1 mm x 1 mm cross section and 100 ⁇ m thickness.
  • BiTe is the material used in the cited patent, and it can be used in embodiments of the invention.
  • other thermoelectric materials can be used for heat switches as well. From the analysis below it follows that the higher the figure of merit of used thermoelectric materials the higher the efficiency of the whole cooling device.
  • thermoelectric heat switches The following estimations show a preferable range of sizes of thermoelectric heat switches. However it should be understood that this is just an example and heat switches of other sizes can be used.
  • a time scale of the device operation can be set by the polarisation time (0.1 s), so a heat transfer taking, say, 10 s, is far too slow.
  • VlNIkG where C is the heat capacity of an EC element, C H ⁇ atsw is total heat capacity of a heat switch, C ⁇ i- ⁇ e is the volume heat capacity of bismuth teiluride, a possible material used in thermocouples, N is the number of thermocouples, h is the height of the thermocouples, G is the ratio of the area of one leg of a thermocouple to its height h, k is the heat diffustvity of BiTe. After a simplification one has two inequalities:
  • microelectromechanical systems can switch from a heat conducting to a heat insulating state.
  • a first working element when a first working element is subject to electric field, it generates heat and its temperature is raised above the temperature of the heat sink.
  • a heat switch between the first EC element and a heat load is in an off state, and a heat switch between the EC element and a heat sink is in an on state, thus allowing for the heat flow from the EC element to the heat sink.
  • the heat flow goes on until the temperatures of the EC element and the heat sink are the same.
  • the electric field is removed and the EC element cools down and its temperature drops below the temperature of the heat load.
  • the heat switch between the EC element and heat load is in an on state, and the heat switch between the EC element and the heat sink is in an off state.
  • This configuration allows for the heat flow from the heat load to the EC element. The heat flow goes on until the temperatures of the EC element and the heat load are the same.
  • the device comprising only one EC element and two heat switches can pump heat from the cold to the hot end.
  • Embodiments comprising more than one EC element can work in a similar fashion.
  • Operation of an embodiment comprising one electrocaloric element and two heat switches shown in Fig. 7 comprises:
  • the operation can be repeated in every device.
  • electrocaloric elements 200 and 210 are at their working temperatures T w ⁇ oo and Tw 2 w respectively, what corresponds to an optimum electrocaloric effect of the materia! used.
  • the working temperatures are chosen so that Tw2io ⁇ Tw ⁇ oo, Tw 2 io is close to the heat source (20) temperature T20 and Tw2oo is close to the ambient (10) temperature T 10 .
  • An optimum difference between adjacent working temperatures depends on the value of the eiectrocaloric effect among other factors.
  • an initial configuration of a cooling device is: 210 is depolarised, 200 is polarised, both are at their working temperatures, and all heat switches (100, 110, and 120) are in an off state, i.e. they do not conduct heat.
  • This configuration can be achieved by a proper biasing of the heat switches.
  • the heat switch 100 should pump some heat from 200 to the ambient 10, etc.
  • Stable cooling at constant cooling power is achieved by running elementary cooling cycles. Each cycle comprises four stages: • (/) Application of bias to 210. Its temperature rises due to the electrocaloric effect. At the same time 200 is depolarised. Its temperature decreases due to electrocaloric effect. All heat switches 100, 110, and 120 are in an off state.
  • Heat switch 110 is turned on, i.e. it conducts heat. Switches 100 and 120 are off. Heat is transferred from 210 to 200.
  • the cycle described can be generalised and used in embodiments with cascades comprising any number of electrocaloric elements.
  • the described cycle is just an example and other cycles can be run on devices according to embodiments of the invention.
  • Electrocaloric element 210 is utilised as a heat source in the previous stage comprising the electrocaloric element 200.
  • Electrocaloric element 220 is utilised as a heat source in the stage comprising eiectrocaloric elements 200 and 210.
  • Electrocaloric element 230 is utilised as a heat source in the stage comprising electrocaloric elements 200, 210, and 220.
  • the system comprises four cooling devices: a first device comprising an electrocaioric element 200 and heat switches 100 and 110, a second device comprising an electrocaloric element 210 and heat switches 110 and 120, a third device comprising an electrocaloric element 220 and heat switches 120 and 130, and a fourth device comprising an electrocaloric element 230 and heat switches 130 and 140.
  • the hot end of a fourth device is the cold end of the third device, the hot end of the third device is the cold end of the second device, and the hot end of the second device is the cold end of the first device.
  • the end working element 200 has the highest working temperature of all elements and is separated from the heat sink 10 by the heat switch 100.
  • the end working element 230 has the lowest working temperature of all elements and is separated from the heat source 20 by the heat switch 140.
  • the working elements 200, 210, 220, and 230 of embodiments of the invention can have the working temperatures Tw2oo, Tw ⁇ w, Tw220, and Twzw shown in Table 1.
  • Table 1 An example of working temperatures of a cascaded device comprising four electrocaloric elements in 0 C.
  • cooling devices in a cascaded or parallel system is variable and a cascade comprising four electrocaloric elements is shown for example only.
  • devices comprising an even number of EC elements are in general more efficient and therefore preferable. It is assumed that the energy of a discharge after a deporarization of an EC element is kept in the circuit and used afterwards. Due to the periodic character of the device operation, it can be designed rather easily as an RC circuit. Electrical circuitry is not depicted in Figs. 8, 10, 14 for the sake of clarity.
  • the time of a heat exchange process ⁇ can be varied by changing the heat switches' geometry. However, the faster the heat exchange, the more power is required to offset the heat conductivity between the elements when the heat switches are in an off state. A much more promising approach for reducing the heat exchange time is applying a reverse current to the Peltier elements, and this idea is explored later. For the sake of clarity and in order to consider the working principle of the device, let r be about 1 s until the end of the next paragraph.
  • the time required for a heat exchange between an end element (200 or 230 in Fig. 10, for example) and a heat sink or heat load (10 or 20 in Fig. 10) is 2 ⁇ if neither heat sink nor heat load change their temperature upon the heat exchange.
  • each stage (/, ii, Hi and /V) comprises either fast polarisation/depolarisation processes or slow heat conduction processes, but never both at the same time.
  • each heat exchange process is either between 200 and 210 or between 200 and 10 or 210 and 20. The former takes r seconds, the latter two take 2 ⁇ seconds, and the polarisation takes negligible time comparing to ⁇ . That is why it is preferable to use even numbers of electrocaioric elements in the proposed device - otherwise each of the four stages would involve heat transfer to the heat sink/heat load, thus slowing down the whole cycle and reducing the cooling power.
  • ⁇ is close to the polarisation time ⁇ poi, then it changes nothing in the principle of operation and this discussion, but the time notation in Fig. 9 (r, 3r, 4r, . . . ) will be different. It should be understood that embodiments comprising an odd number of electrocaloric elements can also be used.
  • stage /7 (see Fig. 9) can be started before stage / is finished (the same holds with stages /V and Hi, respectively).
  • heat switch // can be turned on to start the heat conduction.
  • a working thermodynamic cycle of an electrocaioric element is depicted in Fig. 11 using the variables T and S, where T is temperature and S is entropy. If stage // (and /V) start after stages / (and Hi respectively) finish, then an element passes through the points 1-2 -3-4 1 of the diagram.
  • stage H or JV
  • point 2 or 4
  • the cycle will be closer to the ideal Carnot cycle 1- 2-3-4.
  • This approach will allow an increase in the inherent efficiency of the energy transfer inside the electrocaloric elements. Examples of such energy interconversions are: electrical energy at the electrodes ⁇ energy of the ferroelectric, and structural ordering ⁇ heat energy of the the crystal lattice.
  • the time required for heat exchange between two adjacent EC elements ⁇ can be decreased by using an extra heat conductor parallel to the heat switch. It effectively increases the heat switch's heat conductivity and lowers its thermoelectric figure of merit.
  • these shunts are microactuators fabricated by microelectromechanica! systems technology. One of the possible designs for additional heat conductors is shown in Fig. 12, a.
  • the thermoelectric elements of the heat switch between 200 and 210 are not shown in that Figure for the sake of clarity. Only two electrocaloric elements are shown in the Figure for the sake of clarity. However, this concept can be applied to any number of working elements.
  • Microactuators can be made of a piezoelectric material, e.g.
  • PZT - lead zirconium titanate They can be either compressed ⁇ voltage applied), so that the device does not conduct heat, or stretched (no voltage applied) so that there is a physical contact between the two parts to allow heat transfer.
  • the efficiency of such a device depends on the contact surface area S Co mp- It is compared to the plain surface area S P ⁇ ain in Fig. 12, b.
  • Three geometries (ladder - 61 , conical - 62, and spherical - 63) for the heat transfer elements are shown in Fig. 12, b along with their effective contact surface area normalised to the plain surface area.
  • the size of such a device can vary, but for the sizes considered in the current research, a reasonable value is 10-100 ⁇ m in both diameter and depth.
  • conical (62) and spherical (63) shapes could be hard to produce
  • the ladder type projection (61 ) can be produced by a conventional microfabrication technique depicted in Fig. 13. in some embodiments, such a device can be used as a mechanical heat switch between the working elements and end working elements and heat sink/load.
  • a preferable way to manufacture a mechanical heat switch is presented.
  • the procedure is commonplace.
  • a layer of photoresist is deposited on top of Si or other heat conducting materia!.
  • a part of its surface 30 is exposed to the UV radiation.
  • the exposed surface is etched away by diluted acetic acid, for example, so that a trench is formed in the photoresist.
  • a strong etchant e.g. HF
  • stage IH the photoresist is deposited again and a part of its surface 32 is exposed to the UV light, and similarly to step II, a strong etchant is applied at step IV to make a next trench. Finally a part of a complex surface 61 is obtained. Only one trench is shown in Fig. 13, however such a procedure can be realised to produce a number of trenches on the same surface.
  • the work of a heat switch based on a thermoelectric element is modified in the following way.
  • a reverse voltage is applied across the element when it is in the on state (that is no current, heat transfer goes on - for example switch 110 at the stage // ' in Fig. 9).
  • the Peltier effect will effectively pump heat from the hot to the cold eiectrocaloric element that it connects (for example from 210 to 200 in Fig. 9).
  • the application of a voltage with reverse polarity increases the effective heat conductivity of the heat switch, decreases the time required for the heat transfer and increases the cooling power and efficiency.
  • a couple of equations for the heat transfer can be considered (for more details see the Appendix).
  • One of the main results of the calculations is that even a rather small current (0.05 A, for example) decreases ⁇ by several orders of magnitude. This method will be referred to as the active heat conductivity method.
  • Example 1 Calculation of efficiency and cooling power of the proposed device in some embodiments
  • thermoelectric heat switches The operation of some embodiments of the proposed cooling device with thermoelectric heat switches has been simulated using MS Excel ® .
  • the eiectrocaloric effect of each electrocaloric element versus temperature was described by a Gaussian curve with a maximum of 3 0 C.
  • the peaks of the Gaussians are centered at the appropriate working temperatures for each element TW,- and have a width of about 1O 0 C.
  • Embodiments of cascades comprising 2, 4, and 6 electrocaloric elements have been simulated.
  • the system comprises additional electrocaloric elements that are utilised as heat sinks/sources in the previous stages of the cascaded system.
  • This embodiment comprises 6 cooling devices that are cascaded in analogy with cascaded systems described above (shown in Figs. 8 and 10), As an example, the initial temperature of the heat load 20 is 16 0 C for all devices, the initial temperature of the heat sink 10 is 20 0 C for the cascaded device comprising 2 electrocaioric elements, 24 0 C for the cascaded device comprising 4 electrocaioric elements, and 28 0 C for the cascaded device comprising 6 electrocaioric elements.
  • the efficiency of the proposed device depends on how fast the heat is dissipated from a heat sink (component 10 in Figs. 7, 8, 10, and 14, for example).
  • the rate depends mainly on the design of the heat sink. Usually it is a structure with a large surface area and a fan that creates the air flow through it.
  • applied heat that is to be dissipated
  • the relation between the power to be dissipated W and temperature change ⁇ 5Tof the heat sink is linear, and the coefficient is called the heat resistivity: p ⁇ eai - 5T/W.
  • the simulation results for a cascaded device comprising 2 electrocaloric elements at equilibrium are shown in Fig. 15.
  • Four stages of the cooling cycle ⁇ /, /7, /77, and /V) are highlighted (they are the same as in Fig. 9).
  • the temperature of the heat load (component 20 in Figs. 7, 8, 10, and 14, for example) is raised artificially at the end of stage ;/ ' of every cycle simulating the heat generation in a real device.
  • the simulated temperature of the heat sink (component 10 in Figs. 7, 8, 10, and 14) is higher than that of the ambient because of its finite heat resistivity (its temperature should rise in order to dissipate the incoming heat).
  • Fig. 16 shows some important characteristics (for a cascaded device comprising 4 electrocaloric elements shown in Fig. 10), namely the cooiing power, efficiency and the average time r for heat transfer between two adjacent electrocaloric elements (200 and 210, 210 and 220, 220 and 230 in Fig. 10) as a function of the heat conductivity of the switches. So the approach of changing the heat switches' heat conductivity when the device is working can give more options and allows for the optimisation of cooling power versus efficiency.
  • additional heat conductors provide an adjustable option for the design of a particular cooling device so that it could be used either to pump more heat less efficiently or to work at the highest efficiency but with Sower cooling power.
  • additional shunts made of MEMS described above can fulfil the function to change the effective heat conductivity of the heat switches.
  • Example 2 Calculation of efficiency and cooling power of some embodiments of the proposed device comprising heat switches in active heat conductivity mode
  • Embodiments comprising heat switches in active heat conductivity mode are more preferable as the calculation gives more striking results. Some of them are presented in Figs. 17 and 18. Referring to Fig. 17, the efficiency and cooling power of the proposed cooling device versus a difference between heat sink and heat load temperatures, T 10 - T ⁇ o, are presented for some embodiments: a cascaded device comprising 2 electrocaloric elements, a cascaded device comprising 4 electrocaloric elements, and a cascaded device comprising 6 electrocaloric elements at different values of the reversed current passed through heat switches in active heat conductivity mode. The efficiency is expressed in percentage of the idea! Carnot efficiency given by formula (2). Application of quite a small reverse current (when the heat switches are in an on state, i.e.
  • the device parameters used in the calculation are listed in Table 3. Referring to Fig. 18 » efficiency and cooling power versus the reverse current of the same devices are presented. It should be understood that the parameters used are only for the sample calculation, as well as geometric sizes of the electrocaloric elements and heat switches. Any other set of parameters and sizes can be used in the proposed cooling device. Moreover, electrocaloric elements can have different sizes, preferably the size of the working element which is closest to the heat sink should be biggest to account for the heat losses in the previous electrocaloric elements and heat switches.
  • thermoelectric cooling device A comparison of a commercial fully optimised thermoelectric device with an embodiment of the electrocaloric cooling device proposed here is made in Fig. 19.
  • the heat resistance of the thermoelectric cooler is chosen to be very low (close to that of the cooling device suggested): 0.04 0 CW "1 . As seen from Fig.
  • the efficiency of the considered embodiment of the present invention rises with the cooling power, unlike for the thermoelectric cooler.
  • a possible reason is as follows. In order to provide more cooling power, the current through the thermoelectric heat switch should be increased. However, this also increases Joule heating, which is proportiona! to the current squared. As a result, the efficiency falls. In the case of the considered embodiment, if more heat is pumped through the it, the temperature of the cold surface rises, but the energy consumption remains the same. If the heat dissipation at the hot end is fast enough, the efficiency rises with cooling power.
  • N is the number of couples
  • C (JK '1 ) is the heat capacity of an electrocaloric element
  • T Co id (K) is the temperature of an electrocaloric (EC) element with lower initial temperature T Co id (O)(K)
  • T ⁇ ot (K) is the temperature of another EC element with higher initial temperature Tcoi d (O)(K)
  • / (A) is the current passed through the thermoelectric heat switch
  • a is the Seebeck coefficient (VK "1 )
  • k is the heat conductivity (Wcm "1 K '1 )
  • G (cm) is the ratio of a heat switches' cross-sectional area to its height.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)

Abstract

La présente invention se rapporte à un dispositif de refroidissement comportant plusieurs éléments de travail électrocaloriques (200, 210, 220, 230) associés à des températures de travail recouvrant une plage de températures requises. Ces éléments sont séparés par des commutateurs de chaleur (100, 110, 120, 130, 140). Le nombre des éléments électrocaloriques et des commutateurs de chaleur peut être différent dans d'autres modes de réalisation. Le dispositif peut être agencé en cascade ou en parallèle pour assurer un refroidissement plus important. Des commutateurs de chaleur thermoélectriques sont utilisés pour passer d'un état de conduction thermique à un état d'isolation thermique. Dans certains modes de réalisation, les commutateurs thermoélectriques sont remplacés par des commutateurs microélectromécaniques. les Commutateurs thermoélectriques peuvent fonctionner dans un mode thermoconducteur passif. Dans certains modes de réalisation, les commutateurs peuvent fonctionner dans un mode électroconducteur actif, le courant inverse traversant les couples dans l'état bloqué de thermoconduction, et les éléments électrocaloriques peuvent prendre la forme de condensateurs multicouches composés de films minces ferroélectriques.
PCT/GB2005/050207 2004-11-29 2005-11-21 Dispositifs de refroidissement electrocaloriques a semi-conducteurs et procedes associes WO2006056809A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
GB0426230A GB2420662A (en) 2004-11-29 2004-11-29 Electrocaloric colling device with heat switches
GB0426230.9 2004-11-29
US68229505P 2005-05-19 2005-05-19
US60/682,295 2005-05-19

Publications (1)

Publication Number Publication Date
WO2006056809A1 true WO2006056809A1 (fr) 2006-06-01

Family

ID=35788218

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2005/050207 WO2006056809A1 (fr) 2004-11-29 2005-11-21 Dispositifs de refroidissement electrocaloriques a semi-conducteurs et procedes associes

Country Status (1)

Country Link
WO (1) WO2006056809A1 (fr)

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009126344A2 (fr) * 2008-01-15 2009-10-15 Stc.Unm Réfrigérateur électro-calorique et générateur d’énergie pyroélectrique multicouche
WO2011159316A1 (fr) * 2010-06-18 2011-12-22 Empire Technology Development Llc Matériaux à effet électrocalorique et diodes thermiques
WO2012030351A1 (fr) * 2010-09-03 2012-03-08 Empire Technology Development Llc Transfert de chaleur électrocalorique
EP2505913A1 (fr) * 2011-03-30 2012-10-03 Nxp B.V. Dispositif de gestion thermique active et procédé de gestion thermique
US20120267090A1 (en) * 2011-04-20 2012-10-25 Ezekiel Kruglick Heterogeneous Electrocaloric Effect Heat Transfer Device
US20130067935A1 (en) * 2011-09-21 2013-03-21 Ezekiel Kruglick Heterogeneous Electrocaloric Effect Heat Transfer
WO2013043167A1 (fr) * 2011-09-21 2013-03-28 Empire Technology Development Llc Régulation de la contrainte dimensionnelle d'un dispositif de transmission de chaleur à effet électrocalorique
WO2015014853A1 (fr) * 2013-08-01 2015-02-05 Jožef Stefan Institute Procédé pour conversion d'énergie électrocalorique
US9310109B2 (en) 2011-09-21 2016-04-12 Empire Technology Development Llc Electrocaloric effect heat transfer device dimensional stress control
US9318192B2 (en) 2012-09-18 2016-04-19 Empire Technology Development Llc Phase change memory thermal management with electrocaloric effect materials
WO2016156074A1 (fr) 2015-03-30 2016-10-06 Basf Se Commutateur thermique mécanique et procédé
US9500392B2 (en) 2012-07-17 2016-11-22 Empire Technology Development Llc Multistage thermal flow device and thermal energy transfer
EP3106781A1 (fr) * 2015-06-18 2016-12-21 University of Ljubljana Dispositif micro-magnétocalorique
JPWO2016195024A1 (ja) * 2015-06-04 2018-04-05 株式会社村田製作所 冷却デバイス
US10184697B2 (en) 2015-09-18 2019-01-22 Uchicago Argonne, Llc Device for cooling fluid, method for cooling fluid
CN112062554A (zh) * 2020-09-17 2020-12-11 广西大学 一种pstt基高性能陶瓷电卡制冷材料的制备方法
US10890361B2 (en) 2016-06-08 2021-01-12 Carrier Corporation Electrocaloric heat transfer system
CN113066923A (zh) * 2021-03-10 2021-07-02 南方科技大学 一种全静态固体制冷器及其制备方法
CN113163688A (zh) * 2015-12-21 2021-07-23 联合工艺公司 电热热传递模块化堆垛
US11346586B2 (en) 2017-06-16 2022-05-31 Carrier Corporation Electrocaloric heat transfer system with patterned electrodes
US11859878B2 (en) 2018-10-23 2024-01-02 Carrier Corporation Electrocaloric heat transfer system

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436924A (en) * 1967-11-15 1969-04-08 Corning Glass Works Paraelectric refrigeration method and apparatus
US3638440A (en) * 1970-11-20 1972-02-01 Corning Glass Works Closed-cycle electrocaloric refrigerator and method
US3650117A (en) * 1970-06-08 1972-03-21 Liquid Air Canada Paraelectric refrigerator
US3841107A (en) * 1973-06-20 1974-10-15 Us Navy Magnetic refrigeration
US4136525A (en) * 1976-12-30 1979-01-30 International Business Machines Corporation Dielectic refrigerator using orientable defect dipoles
SU914900A1 (ru) * 1980-08-28 1982-03-23 Mo Energeticheskij Institut Низкотемпературная установка i
SU918770A1 (ru) * 1980-07-02 1982-04-07 Московский Ордена Ленина Энергетический Институт Тепловой ключ /его варианты/
US4757688A (en) * 1986-04-01 1988-07-19 Hughes Aircraft Company Solid-state electrocaloric cooling system and method
EP0425165A2 (fr) * 1989-10-26 1991-05-02 Hughes Aircraft Company Dispositif de refroidissement pour basse température utilisant des jonctions porteurs de courant mode supraconducteur/mode non-supraconducteur
US5605048A (en) * 1992-11-05 1997-02-25 Tovarischestvo S Ogranichennoi Otvetstvennostju Libratsia Method of cooling an object with a thermoelectric battery cascade
US5644184A (en) * 1996-02-15 1997-07-01 Thermodyne, Inc. Piezo-pyroelectric energy converter and method
US5867990A (en) * 1997-12-10 1999-02-09 International Business Machines Corporation Thermoelectric cooling with plural dynamic switching to isolate heat transport mechanisms
US6161388A (en) * 1998-12-28 2000-12-19 International Business Machines Corporation Enhanced duty cycle design for micro thermoelectromechanical coolers
US20030026059A1 (en) * 2001-08-03 2003-02-06 Tdk Corporation Multilayer ceramic electronic device
US6595004B1 (en) * 2002-04-19 2003-07-22 International Business Machines Corporation Apparatus and methods for performing switching in magnetic refrigeration systems using thermoelectric switches

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436924A (en) * 1967-11-15 1969-04-08 Corning Glass Works Paraelectric refrigeration method and apparatus
US3650117A (en) * 1970-06-08 1972-03-21 Liquid Air Canada Paraelectric refrigerator
US3638440A (en) * 1970-11-20 1972-02-01 Corning Glass Works Closed-cycle electrocaloric refrigerator and method
US3841107A (en) * 1973-06-20 1974-10-15 Us Navy Magnetic refrigeration
US4136525A (en) * 1976-12-30 1979-01-30 International Business Machines Corporation Dielectic refrigerator using orientable defect dipoles
SU918770A1 (ru) * 1980-07-02 1982-04-07 Московский Ордена Ленина Энергетический Институт Тепловой ключ /его варианты/
SU914900A1 (ru) * 1980-08-28 1982-03-23 Mo Energeticheskij Institut Низкотемпературная установка i
US4757688A (en) * 1986-04-01 1988-07-19 Hughes Aircraft Company Solid-state electrocaloric cooling system and method
EP0425165A2 (fr) * 1989-10-26 1991-05-02 Hughes Aircraft Company Dispositif de refroidissement pour basse température utilisant des jonctions porteurs de courant mode supraconducteur/mode non-supraconducteur
US5605048A (en) * 1992-11-05 1997-02-25 Tovarischestvo S Ogranichennoi Otvetstvennostju Libratsia Method of cooling an object with a thermoelectric battery cascade
US5644184A (en) * 1996-02-15 1997-07-01 Thermodyne, Inc. Piezo-pyroelectric energy converter and method
US5867990A (en) * 1997-12-10 1999-02-09 International Business Machines Corporation Thermoelectric cooling with plural dynamic switching to isolate heat transport mechanisms
US6161388A (en) * 1998-12-28 2000-12-19 International Business Machines Corporation Enhanced duty cycle design for micro thermoelectromechanical coolers
US20030026059A1 (en) * 2001-08-03 2003-02-06 Tdk Corporation Multilayer ceramic electronic device
US6595004B1 (en) * 2002-04-19 2003-07-22 International Business Machines Corporation Apparatus and methods for performing switching in magnetic refrigeration systems using thermoelectric switches

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
J.J. CUOMO, J.P. GILVEY, J.A. VANVECHTEN: "Thermal Switch For Dielectric Refrigerator. October 1979.", IBM TECHNICAL DISCLOSURE BULLETIN, vol. 22, no. 5, 1 October 1979 (1979-10-01), New York, US, pages 2127 - 2130, XP002368409 *
R. RADEBAUGH, W.N. LAWLESS, J.D. SIEGWARTH, A.J. MORROW: "Feasability of electrocaloric refrigeration for the 4-15 K temperature range", CRYOGENICS, April 1979 (1979-04-01), pages 187 - 208, XP008060075 *
S.B. LANG: "Cryogenic refrigeration utilizing the electrocaloric effect in pyroelectric lithium sulfate monohydrate", FERROELECTRICS, vol. 11, 1976, pages 519 - 523, XP008060229 *

Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009126344A3 (fr) * 2008-01-15 2009-12-30 Stc.Unm Réfrigérateur électro-calorique et générateur d’énergie pyroélectrique multicouche
WO2009126344A2 (fr) * 2008-01-15 2009-10-15 Stc.Unm Réfrigérateur électro-calorique et générateur d’énergie pyroélectrique multicouche
CN102947961A (zh) * 2010-06-18 2013-02-27 英派尔科技开发有限公司 电热效应材料和热二极管
WO2011159316A1 (fr) * 2010-06-18 2011-12-22 Empire Technology Development Llc Matériaux à effet électrocalorique et diodes thermiques
US9508913B2 (en) 2010-06-18 2016-11-29 Empire Technology Development Llc Electrocaloric effect materials and thermal diodes
WO2012030351A1 (fr) * 2010-09-03 2012-03-08 Empire Technology Development Llc Transfert de chaleur électrocalorique
US8769967B2 (en) 2010-09-03 2014-07-08 Empire Technology Development Llc Electrocaloric heat transfer
US9939141B2 (en) 2011-03-30 2018-04-10 Nxp B.V. Active thermal management device and thermal management method
CN102740659B (zh) * 2011-03-30 2015-03-25 Nxp股份有限公司 主动热管理装置和热管理方法
CN102740659A (zh) * 2011-03-30 2012-10-17 Nxp股份有限公司 主动热管理装置和热管理方法
EP2505913A1 (fr) * 2011-03-30 2012-10-03 Nxp B.V. Dispositif de gestion thermique active et procédé de gestion thermique
WO2012144995A1 (fr) * 2011-04-20 2012-10-26 Empire Technology Development Llc Dispositif de transfert de chaleur à effet électrocalorique hétérogène
US20120267090A1 (en) * 2011-04-20 2012-10-25 Ezekiel Kruglick Heterogeneous Electrocaloric Effect Heat Transfer Device
US9157669B2 (en) 2011-04-20 2015-10-13 Empire Technology Development Llc Heterogeneous electrocaloric effect heat transfer device
US9310109B2 (en) 2011-09-21 2016-04-12 Empire Technology Development Llc Electrocaloric effect heat transfer device dimensional stress control
US8739553B2 (en) 2011-09-21 2014-06-03 Empire Technology Development Llc Electrocaloric effect heat transfer device dimensional stress control
CN103814259B (zh) * 2011-09-21 2015-12-16 英派尔科技开发有限公司 电热效应热传递装置尺寸应力控制
CN103814259A (zh) * 2011-09-21 2014-05-21 英派尔科技开发有限公司 电热效应热传递装置尺寸应力控制
WO2013043167A1 (fr) * 2011-09-21 2013-03-28 Empire Technology Development Llc Régulation de la contrainte dimensionnelle d'un dispositif de transmission de chaleur à effet électrocalorique
US20130067935A1 (en) * 2011-09-21 2013-03-21 Ezekiel Kruglick Heterogeneous Electrocaloric Effect Heat Transfer
US9671140B2 (en) 2011-09-21 2017-06-06 Empire Technology Development Llc Heterogeneous electrocaloric effect heat transfer
US9500392B2 (en) 2012-07-17 2016-11-22 Empire Technology Development Llc Multistage thermal flow device and thermal energy transfer
US9318192B2 (en) 2012-09-18 2016-04-19 Empire Technology Development Llc Phase change memory thermal management with electrocaloric effect materials
CN105593616B (zh) * 2013-08-01 2017-12-26 约塞夫史蒂芬学院 用于电热能量转换的方法
CN105593616A (zh) * 2013-08-01 2016-05-18 约塞夫史蒂芬学院 用于电热能量转换的方法
WO2015014853A1 (fr) * 2013-08-01 2015-02-05 Jožef Stefan Institute Procédé pour conversion d'énergie électrocalorique
US9915446B2 (en) 2013-08-01 2018-03-13 Gorenje D.D. Method for electrocaloric energy conversion
WO2016156074A1 (fr) 2015-03-30 2016-10-06 Basf Se Commutateur thermique mécanique et procédé
JPWO2016195024A1 (ja) * 2015-06-04 2018-04-05 株式会社村田製作所 冷却デバイス
WO2016203001A3 (fr) * 2015-06-18 2017-03-16 University Of Ljubljana Dispositif micro-magnétocalorique
EP3106781A1 (fr) * 2015-06-18 2016-12-21 University of Ljubljana Dispositif micro-magnétocalorique
US10184697B2 (en) 2015-09-18 2019-01-22 Uchicago Argonne, Llc Device for cooling fluid, method for cooling fluid
CN113163688A (zh) * 2015-12-21 2021-07-23 联合工艺公司 电热热传递模块化堆垛
US10890361B2 (en) 2016-06-08 2021-01-12 Carrier Corporation Electrocaloric heat transfer system
US11346586B2 (en) 2017-06-16 2022-05-31 Carrier Corporation Electrocaloric heat transfer system with patterned electrodes
US11859878B2 (en) 2018-10-23 2024-01-02 Carrier Corporation Electrocaloric heat transfer system
CN112062554A (zh) * 2020-09-17 2020-12-11 广西大学 一种pstt基高性能陶瓷电卡制冷材料的制备方法
CN112062554B (zh) * 2020-09-17 2022-08-19 广西大学 一种pstt基高性能陶瓷电卡制冷材料的制备方法
CN113066923A (zh) * 2021-03-10 2021-07-02 南方科技大学 一种全静态固体制冷器及其制备方法

Similar Documents

Publication Publication Date Title
WO2006056809A1 (fr) Dispositifs de refroidissement electrocaloriques a semi-conducteurs et procedes associes
Navid et al. Pyroelectric energy harvesting using Olsen cycles in purified and porous poly (vinylidene fluoride-trifluoroethylene)[P (VDF-TrFE)] thin films
Torelló et al. Electrocaloric coolers: a review
Ju Solid-state refrigeration based on the electrocaloric effect for electronics cooling
Sebald et al. On thermoelectric and pyroelectric energy harvesting
Lee et al. Pyroelectric waste heat energy harvesting using heat conduction
Guo et al. Design and modeling of a fluid-based micro-scale electrocaloric refrigeration system
JP3955437B2 (ja) ピロ電気変換システム
GB2420662A (en) Electrocaloric colling device with heat switches
US20130074900A1 (en) Electrocaloric Refrigerator and Multilayer Pyroelectric Energy Generator
McKinley et al. A novel thermomechanical energy conversion cycle
WO2018208680A1 (fr) Refroidissement électrocalorique à actionnement électrostatique
Meng et al. Electrocaloric cooling over high device temperature span
TWI502779B (zh) 用於使用兩相熱轉移之快速熱循環以將熱量轉化為電及用於其他用途之裝置及方法
WO2007099279A1 (fr) Films épais et minces utilisés pour la production d'énergie et le refroidissement
Siao et al. Pyroelectric waste heat energy harvesting using the Olsen cycle on Pb (Zr, Ti) O3-Pb (Ni, Nb) O3 ceramics
Mart et al. Energy harvesting in the back-end of line with CMOS compatible ferroelectric hafnium oxide
Najmi et al. Electrocaloric devices part II: All-solid heat pump without moving parts
KR101761459B1 (ko) 에너지 하베스팅 소자, 전기열량 냉각 소자, 이의 제조 방법 및 이를 포함하는 모놀리식 소자
Chen et al. Improved pyroelectric figures of merit of Mn-doped Zr-rich lead zirconate titanate bulk ceramics near room temperature for energy harvesting applications
CN100557340C (zh) 一种微制冷器及其制冷方法
Cai et al. Polymeric nanocomposites for electrocaloric refrigeration
Kar-Narayan et al. Electrocaloric multilayer capacitors
Pilon et al. Pyroelectric energy conversion
Resende et al. Solid-state electrocaloric cooler controlled by a thermal switch

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KM KN KP KR KZ LC LK LR LS LT LU LV LY MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU LV MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 05808829

Country of ref document: EP

Kind code of ref document: A1