CN212367151U - Inverter circuit - Google Patents
Inverter circuit Download PDFInfo
- Publication number
- CN212367151U CN212367151U CN202020803918.0U CN202020803918U CN212367151U CN 212367151 U CN212367151 U CN 212367151U CN 202020803918 U CN202020803918 U CN 202020803918U CN 212367151 U CN212367151 U CN 212367151U
- Authority
- CN
- China
- Prior art keywords
- auxiliary
- main switch
- switch
- resonant
- resonance
- Prior art date
- Legal status (The legal status 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 status listed.)
- Active
Links
- 239000003990 capacitor Substances 0.000 claims description 44
- 238000004804 winding Methods 0.000 claims description 28
- 238000010586 diagram Methods 0.000 description 18
- 230000007423 decrease Effects 0.000 description 5
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Images
Landscapes
- Inverter Devices (AREA)
Abstract
The embodiment of the utility model relates to electronic power technical field discloses an inverter circuit, including the DC power supply, three auxiliary resonance circuit, three-phase inverter and the three-phase load that connect gradually, wherein, each auxiliary resonance circuit includes a resonance inductance, and three-phase inverter includes three bridge arm, and each bridge arm includes two main switch and two resonance electric capacity, one parallelly connected on the main switch has one resonance electric capacity, the resonance inductance on the three auxiliary resonance circuit are connected with the output of three bridge arm respectively, and when the main switch need switch over the state, resonance inductance and/or resonance electric capacity that are located same looks with the main switch produce the resonance, so that the main switch can realize that zero current turn-off and zero voltage switch on.
Description
Technical Field
The embodiment of the utility model provides a relate to electron electric power technical field, in particular to inverter circuit.
Background
The resonant pole type soft inverter is an electronic component in which the voltage of a direct current link is not affected by resonance, an auxiliary circuit is connected to the output end of the inverter, when the resonant pole type soft inverter is used in combination with a three-phase inverter, the auxiliary resonant circuit of the resonant pole type soft inverter is usually connected to three output ends of the three-phase inverter, and through the auxiliary resonant circuit, the pole voltages of two groups of power switching devices of the three-phase inverter on each phase can generate resonance in a field, so that a condition is created for zero-voltage conduction or zero-current turn-off of the switching devices, and when the whole system circuit is subjected to pulse width modulation, the inverter and the auxiliary resonant circuit can be triggered simultaneously.
In implementing the embodiments of the present invention, the inventor finds that there are at least the following problems in the above related art: at present, in an inverter circuit topological structure using a resonant pole type soft inverter, 4 active auxiliary switches are needed, or a large-capacity electrolytic capacitor is connected in series on a direct current bus, so that a switching device can realize zero current turn-off and zero voltage turn-on.
SUMMERY OF THE UTILITY MODEL
To the above-mentioned defect of prior art, the embodiment of the utility model provides an aim at provides a simple structure and can realize that zero current turn-off and zero voltage switch on's inverter circuit.
The embodiment of the utility model provides an aim at is realized through following technical scheme:
in order to solve the above technical problem, an embodiment of the present invention provides an inverter circuit, include:
a direct current power supply;
three auxiliary resonance circuits, three input ends of which are respectively connected with the output end of the direct current power supply, and each auxiliary resonance circuit comprises a resonance inductor;
the three-phase inverter is provided with three bridge arms, each bridge arm comprises two main switches and two resonant capacitors, one main switch is connected with one resonant capacitor in parallel, and the resonant inductors on the three auxiliary resonant circuits are respectively connected with the output ends of the three bridge arms;
the input end of the three-phase load is respectively connected with the three output ends of the three bridge arms; wherein,
when the main switch needs to switch the state, the resonance inductor and/or the resonance capacitor which are positioned on the same phase with the main switch generate resonance, so that the main switch realizes zero current turn-off and zero voltage turn-on.
In some embodiments, any of the legs comprises: the resonant inductor comprises a first main switch and a second main switch, wherein an emitter of the first main switch is connected with a collector of the second main switch, and one end of the resonant inductor is connected between the emitter of the first main switch and the collector of the second main switch.
In some embodiments, the auxiliary resonant circuit in the same phase as the first main switch and the second main switch further comprises:
the unidirectional transformer comprises a primary winding and a secondary winding, and one end of the secondary winding is connected with the other end of the resonant inductor;
a first auxiliary switch, an emitter of which is connected with a cathode of the direct current power supply, and a collector of which is connected with the other end of the secondary winding;
and a second auxiliary switch having an emitter connected to the collector of the first auxiliary switch and a collector connected to the anode of the dc power supply.
In some embodiments, the auxiliary resonant circuit in the same phase as the first main switch and the second main switch further comprises:
the anode of the first auxiliary diode is connected with one end of the primary winding, and the cathode of the first auxiliary diode is connected with the anode of the direct-current power supply;
the anode of the second auxiliary diode is connected with the other end of the primary winding, and the cathode of the second auxiliary diode is connected with the anode of the direct-current power supply;
the anode of the third auxiliary diode is connected with the cathode of the direct-current power supply, and the cathode of the third auxiliary diode is connected with the other end of the primary winding;
and the anode of the fourth auxiliary diode is connected with the cathode of the direct-current power supply, and the cathode of the fourth auxiliary diode is connected with one end of the primary winding.
In some embodiments, a freewheeling diode is connected in parallel between the collector and the emitter of each of the first and second main switches in reverse direction.
In some embodiments, the first and second main switches are insulated gate bipolar transistors.
In some embodiments, a reverse diode is connected in parallel between the collector and the emitter of the first auxiliary switch and the second auxiliary switch in reverse direction.
In some embodiments, the first auxiliary switch and the second auxiliary switch are insulated gate bipolar transistors.
In some embodiments, the three-phase inverter further comprises:
and the output end of the driving chip is respectively connected with the bases of the first main switch, the second main switch, the first auxiliary switch and the second auxiliary switch and is used for outputting a pulse signal to control the on-off of the first main switch, the second main switch, the first auxiliary switch and/or the second auxiliary switch.
In some embodiments, each of the three phase loads includes a load capacitor and a load inductor, the load capacitor being connected in series with the load inductor.
Compared with the prior art, the beneficial effects of the utility model are that: be different from prior art's condition, the embodiment of the utility model provides an inverter circuit, including the DC power supply, three auxiliary resonance circuit, three-phase inverter and the three-phase load that connect gradually, wherein, each auxiliary resonance circuit includes a resonance inductance, and three-phase inverter includes three bridge arm, and each bridge arm includes two main switch and two resonant capacitor, one parallelly connected on the main switch has one resonant capacitor, the last resonance inductance of three auxiliary resonance circuit are connected with the output of three bridge arm respectively, and when the main switch need switch over the state, resonance inductance and/or resonant capacitor that are located same looks with the main switch produce the resonance, so that the main switch can realize that zero current turn-off and zero voltage switch on.
Drawings
The embodiments are illustrated by the figures of the accompanying drawings which correspond and are not meant to limit the embodiments, in which elements/blocks having the same reference number designation may be represented by like elements/blocks, and in which the drawings are not to scale unless otherwise specified.
Fig. 1 is a schematic structural diagram of an inverter circuit according to an embodiment of the present invention;
fig. 2 is a schematic circuit diagram of an inverter circuit according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a single-phase circuit structure of the inverter circuit shown in FIG. 2;
FIG. 4 is a waveform diagram illustrating operation of the single phase circuit of FIG. 3;
FIG. 5(a) is an equivalent circuit diagram of the single-phase circuit of FIG. 3 in a first mode of operation;
FIG. 5(b) is an equivalent circuit diagram of the single-phase circuit shown in FIG. 3 in a second mode of operation;
FIG. 5(c) is an equivalent circuit diagram of the single-phase circuit shown in FIG. 3 in a third operating mode;
FIG. 5(d) is an equivalent circuit diagram of the single-phase circuit of FIG. 3 in a fourth mode of operation;
FIG. 5(e) is an equivalent circuit diagram of the single-phase circuit shown in FIG. 3 in a fifth operating mode;
FIG. 5(f) is an equivalent circuit diagram of the single-phase circuit of FIG. 3 in a sixth mode of operation;
FIG. 5(g) is an equivalent circuit diagram of the single-phase circuit shown in FIG. 3 in a seventh operating mode;
fig. 5(h) is an equivalent circuit diagram of the single-phase circuit shown in fig. 3 in an eighth operation mode.
Detailed Description
The present invention will be described in detail with reference to the following embodiments. The following examples will assist those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any way. It should be noted that various changes and modifications can be made by one skilled in the art without departing from the spirit of the invention. These all belong to the protection scope of the present invention.
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
It should be noted that, if not conflicted, the various features of the embodiments of the invention can be combined with each other and are within the scope of protection of the present application. In addition, although the functional blocks are divided in the device diagram, in some cases, the blocks may be divided differently from those in the device. Further, the terms "first," "second," "third," and the like, as used herein, do not limit the data and the execution order, but merely distinguish the same items or similar items having substantially the same functions and actions.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
Furthermore, the technical features mentioned in the embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
The requirement of the current industrial production on the switching frequency of the inverter is higher, so that the high frequency is necessarily the leading direction of the development of the inverter in the future, but in the hard switching inverter, the higher the switching frequency of the switching device is, the larger the switching loss is, and the development trend of the high frequency of the inverter is severely limited. Therefore, the soft switching technology is rapidly developed, when the inverter works in a high-frequency state, the soft switching of the power switching devices in the inverter can be well realized through the soft switching technology, the switching loss of the power switching devices is further reduced, and the efficiency of the inverter is improved.
In various soft switching inverters in the modern industrial field, the performance of a resonant pole type soft switching inverter is outstanding, when a three-phase inverter is combined to be applied to an inverter system, due to the resonance characteristic of the inverter, a condition can be created for zero-voltage conduction or zero-current turn-off of a switching device in the inverter system, and due to the control characteristic of the inverter, the three-phase inverter and an auxiliary resonant circuit in the inverter system can be simultaneously controlled without mutual influence. However, in the prior art, an inverter system combining a three-phase inverter and a resonant pole soft switching inverter is generally complex in structure of an inverter circuit, and the inverter is difficult to control, and it is difficult to achieve zero current turn-off and zero voltage turn-on of a main switch in the three-phase inverter.
In order to solve the above problem, the present application provides an inverter circuit, which has a resonant capacitor connected in parallel to a main switch of a three-phase inverter, and also has a resonant inductor in an auxiliary resonant circuit, where the resonant capacitor and a resonant voltage can resonate to enable the main switch to implement zero current turn-off and zero voltage turn-on. The inverter circuit that this application embodiment provided need not establish ties the junya electric capacity of large capacity at direct current link and just can solve the problem that the dc-to-ac converter neutral point position changes, realizes that zero current turn-off and zero voltage switch on. At the same time, there is no need to set the inductor current threshold for controlling the auxiliary switch in the auxiliary resonant circuit, and thus no need to set additional detection and timing circuits. In addition, because the transformer is used for assisting the commutation, only two auxiliary switches are needed on the resonance auxiliary circuit, and the soft switching of the switching devices in the inverter system can be realized.
Specifically, the embodiments of the present invention will be further explained with reference to the drawings.
The embodiment of the present invention provides an inverter circuit, please refer to fig. 1, which shows the embodiment of the present invention provides an inverter circuit's structural schematic diagram, this inverter circuit 100 includes: a dc power source 110, three auxiliary resonant circuits 120, a three-phase inverter 130, and a three-phase load 140. Wherein,
the dc power supply 110 is a rectified power supply capable of rectifying ac power into dc power or a dc power supply generated by connecting batteries in series and parallel.
Three input terminals of the three auxiliary resonant circuits 120 are respectively connected to the output terminal of the dc power supply 110, and each of the auxiliary resonant circuits (121, 122, 123) includes a resonant inductor (L)ra、Lrb、Lrc). The three auxiliary resonant circuits 120 serve as a dc link for modulating the dc power output by the dc power supply 110.
Three input ends of the three-phase inverter 130 are respectively connected with three output ends of the three auxiliary resonant circuits 120, the three-phase inverter 130 includes three bridge arms (131, 132, 133), and each of the bridge arms (131, 132, 133) includes two main switches SnAnd two resonant capacitors CrnOne said main switch SnThe resonant capacitor C is connected in parallelrnResonant inductances (L) on the three auxiliary resonant circuits 120ra、Lrb、Lrc) Are respectively connected with the output ends of the three bridge arms (131, 132, 133). The three-phase inverter 130 can convert the dc power output from the dc power supply 110 into ac power and output the ac power.
The input end of the three-phase load 140 is connected to the three output ends of the three bridge arms (131, 132, 133), respectively.
Note that n is a positive integer of 1 or more, and is used to indicate a reference numeral for each of the same devices.
At the main switch SnWhen the state needs to be switched, the main switch S is connected with the switchnThe resonance inductances (L) being on the same phasera、Lrb、Lrc) And/or the resonant capacitance CrnGenerates resonance so that the resonance capacitance CrnTo zero, so that the main switch achieves zero current turn-off and zero voltage turn-on.
In some embodiments, please refer to fig. 2 together, which shows a schematic circuit structure diagram of an inverter circuit provided in an embodiment of the present invention, based on the inverter circuit shown in fig. 1, since a topology structure of each auxiliary resonant circuit in the three auxiliary resonant circuits 120 is the same, and a topology structure of each bridge arm in the three-phase inverter 130 is the same, the circuit structure of the inverter circuit is described below with the auxiliary resonant circuit and the bridge arm located on the same phase, please refer to fig. 3 together, which shows a schematic single-phase circuit structure diagram of the inverter circuit shown in fig. 2. Wherein,
the bridge arm includes: first main switch S1And a second main switch S2Said first main switch S1And said second main switch S2The collector connection of said resonant inductor LrIs connected to the first main switch S1And said second main switch S2Between the collectors. The first main switch S1Between the collector and the emitter of the diode D is reversely connected in parallel with a freewheeling diode D1Said second main switch S2Between the collector and the emitter of the diode D is reversely connected in parallel with a freewheeling diode D2. The first main switch S1A resonant capacitor C is connected in parallel between the collector and the emitterr1Said second main switch S2A resonant capacitor C is connected in parallel and reversely between the collector and the emitterr2. The first main switch S1And said second main switch S2Is an insulated gate bipolar transistor.
And the first main switch S1And said second main switch S2The auxiliary resonance circuit located in the same phase further includes: unidirectional transformer, first auxiliary switch Sa1A second auxiliary switch Sa2A first auxiliary diode Da1A second auxiliary diode Da2A third auxiliary diode Da3And a fourth auxiliary diode Da4。
The unidirectional transformer comprises a primary winding n1And a secondary winding n2The secondary winding n2Is connected with the other end of the resonant inductor.
The first auxiliary switch Sa1Is connected to the cathode of the dc power supply 110, the first auxiliary switch Sa1Collector electrode of and the secondary winding n2The other end of the connecting rod is connected. The second auxiliary switch Sa2And said first auxiliary switch Sa1The collector of the second auxiliary switch Sa2Is connected to the anode of the dc power supply 110. The first auxiliary switch Sa1And said second auxiliary switch Sa2A reverse parallel diode is connected between the collector and the emitter in reverse parallel. The first auxiliary switch Sa1And said second auxiliary switch Sa2Is an insulated gate bipolar transistor.
The first auxiliary diode Da1And the anode of the primary winding n1Is connected to the first auxiliary diode Da1Is connected to the anode of the dc power supply 110. The second auxiliary diode Da2And the anode of the primary winding n1Is connected to the other end of the second auxiliary diode Da2Is connected to the anode of the dc power supply 110. The third auxiliary diode Da3Is connected to the cathode of the dc power supply 110, and the third auxiliary diode Da3Of the cathode and the primary winding n1The other end of the connecting rod is connected. The fourth auxiliary diode Da4Is connected to the cathode of the dc power supply 110, and the fourth auxiliary diode Da4Of the cathode and the primary winding n1Is connected at one end.
Each phase load of the three-phase load comprises a load capacitor (Ra, R)b、Rc) And a load inductor (L)a、Lb、Lc) Said load capacitance (R)a、Rb、Rc) Is connected in series (L) with the load inductancea、Lb、Lc)。
In some embodiments, the three-phase inverter further comprises: a driving chip (not shown) having output terminals respectively connected to the first main switch S1The second main switch S2The first auxiliary switch Sa1And said second auxiliary switch Sa2For outputting a pulse signal to control the first main switch S1The second main switch S2The first auxiliary switch Sa1And/or the second auxiliary switch Sa2Make and break of (2).
Since the switching devices in each phase path in the three-phase circuit can be independently controlled, the embodiment of the present invention takes the single-phase equivalent circuit of the inverter shown in fig. 2 (i.e., the single-phase circuit shown in fig. 3) as an example, and analyzes the operating state and the switching process of the switching devices in the single-phase circuit, specifically, please refer to fig. 3 and fig. 4 together, and fig. 5(a), fig. 5(b), fig. 5(c), fig. 5(d), fig. 5(e), fig. 5(f), fig. 5(g), and fig. 5 (h). Fig. 4 is a waveform diagram of the single-phase circuit shown in fig. 3, fig. 5(a), fig. 5(b), fig. 5(c), fig. 5(d), fig. 5(e), fig. 5(f), fig. 5(g), and fig. 5(h) are equivalent circuit diagrams of the single-phase circuit shown in fig. 3 in eight operating modes within one switching period, and it should be noted that the embodiment of the present invention analyzes that the load current is positive, and t-t in fig. 4 is taken as an example0The period is an initial state of the single-phase circuit as an example.
In a first mode of operation (corresponding to t-t in fig. 4)0Phase), see fig. 3, fig. 4 and fig. 5(a) together, which is the initial state of the single-phase circuit, during the operation mode, the auxiliary resonant circuit 120 stops operating, and the load current I0All-slave freewheeling diode D2Through the stage of said first main switch S1In the off state, the second main switch S2The single-phase circuit works stably in a conducting state, and the resonant capacitor Cr1Terminal voltage u ofCr1Is equal to the voltage drop E across the DC power supply 110, i.e., uCr1E, the resonant capacitance Cr2Terminal voltage u ofCr2Is 0, i.e. uCr20, flows through the resonant inductor LrCurrent i ofLrIs also 0, iLr＝0。
In the second operating mode (corresponding to t in FIG. 4)0-t1Stage), please refer to fig. 3, fig. 4 and fig. 5(b) together, the driving chip is at t0Constantly outputting a low level pulse signal to turn off the second main switch S2Simultaneously outputting a high level pulse signal to turn on the second auxiliary switch Sa2. The second main switch S2Before turning off, as no current flows through the second main switch S2Said second main switch S2Zero current soft turn-off is realized; and due to the resonant inductance LrIs reduced to flow through the second auxiliary switch Sa2So that said second auxiliary switch Sa2Soft turn-on under zero current conditions is achieved. At the time of opening the second auxiliary switch Sa2Then, the second auxiliary diode Da2And the fourth auxiliary diode Da4Also starts to conduct, the resonant inductor LrThe voltage is (1-k) E, wherein k is the resonance inductance LrE is the voltage across the dc power supply 110, and the resonant inductor LrIs charged with current iLrInitially linearly increasing, flowing through said resonant inductor LrCurrent i ofLrAnd through the freewheeling diode D2Current i ofD2The sum of which is equal to the load current I0. The second mode of operation being at t1At the end of the time, the current flows through the resonant inductor LrCurrent i ofLrLinearly increasing to equal the load current I0Flows through the freewheeling diode D2Current i ofD2Is 0, the freewheeling diode D2And naturally shutting down.
In a third operating mode (corresponding to t in fig. 4)1-t2Stage), please refer to fig. 3, fig. 4 and fig. 5(c) together, at t1At the moment, the resonant inductance LrThe resonant capacitor Cr1And said resonant capacitor Cr2Starting to resonate, the resonant capacitor Cr1Starting to discharge, the resonant capacitor Cr1Terminal voltage u ofCr1Gradually decreasing from E, the resonant capacitance Cr2Starting to charge the resonant capacitor Cr2Terminal voltage u ofCr2Starting from 0, the resonant inductance L is gradually increasedrIs continuously charged and flows through the resonant inductor LrCurrent i ofLrFrom I0The increase continues. When the resonant capacitor Cr1End capacitor u ofCr1Decreases to kE, flows through the resonant inductor LrCurrent i ofLrIncreases to a forward maximum, after which the resonant inductance LrStarts to discharge, flows through the resonant inductor LrCurrent i ofLrGradually decrease until t2End of time, the resonant capacitor Cr1Terminal voltage u ofCr1Reduced to 0, the resonant capacitance Cr2Terminal voltage u ofCr2Increases to E and flows through the resonant inductor LrCurrent i ofLrIs reduced to I1。
In a fourth operating mode (corresponding to t in fig. 4)2-t3Stage), please refer to fig. 3, fig. 4 and fig. 5(d) together, at t2At the moment, the freewheel diode D1Conducting, and outputting high-level pulse signal to turn on the first main switch S through the drive chip1Because in the first main switch S1Before opening, with the first main switch S1The resonance capacitor C connected in parallelr1Terminal voltage u ofCr1Has been reduced to 0, and therefore, the first main switch S1And the zero-voltage fast turn-on is realized. From t2At the beginning of the moment, the resonant inductance LrBears a reverse voltage value kE and flows through the resonance inductor LrCurrent i ofLrStarting linear decrease until t3At the end of the time, flows through the resonant inductor LrCurrent i ofLrIs reduced to I0Said freewheeling diode D1And naturally shutting down.
In the fifth operating mode (corresponding to t in FIG. 4)3-t4Stage), please refer to fig. 3, fig. 4 and fig. 5(e) together, at t3At the moment of time, the time of day,the resonance inductor LrThe reverse voltage value born by the inductor is still kE and flows through the resonant inductor LrCurrent i ofLrBegins to continue decreasing linearly through the resonant inductor LrCurrent i ofLrAnd flows through the first main switch S1Current i ofS1The sum of which is equal to the load current I0Up to t4At the end of the time, flows through the resonant inductor LrCurrent i ofLrReduced to 0, load current I0All flows through the first main switch S1I.e. through the first main switch S1Current i ofS1Is I0。
In the sixth operating mode (corresponding to t in fig. 4)4-t5Stage), please refer to fig. 3, fig. 4 and fig. 5(f) together, at t4At the moment, the second auxiliary diode D is turned off by outputting a low-level pulse signal through a driving chipa2. Due to the second auxiliary diode D being turned offa2Before flowing through the second auxiliary diode Da2Current i ofSa2Has been reduced to 0, so that said second auxiliary diode Da2Soft turn-off under zero current conditions is achieved. In this mode, the load current I0All flows through the first main switch S1The auxiliary resonance circuit does not work, and the single-phase circuit reaches a stable state until t5End of time, when finished, the first main switch S1Off, the resonant capacitor Cr1Terminal voltage u ofCr1Is 0, i.e. uCr10, said resonant capacitance Cr2Terminal voltage u ofCr2Is equal to the voltage drop E across the DC power supply 110, i.e., uCr1E, flows through a resonant inductor LrCurrent i ofLrIs also 0, iLr＝0。
In the seventh operating mode (corresponding to t in FIG. 4)5-t6Phase), please refer to fig. 3, fig. 4 and fig. 5(g) together, at t5At the moment, the first auxiliary diode D is opened by outputting a high-level pulse signal through a driving chipa1Simultaneously outputting a low level pulse signal to turn off the first main switch S1. Due to the resonance inductance LrThe first auxiliary diode D is reduceda1Current rise rate at turn-on, so that the first auxiliary diode Da1Realizes zero current soft turn-on and turns off the first main switch S1And with said first main switch S1The resonance capacitor C connected in parallelr1The first main switch S is reduced1A rate of rise of terminal voltage at the moment of turn-off, whereby said first main switch S1A zero voltage soft turn off is achieved. In the first auxiliary diode Da1After being turned on, the first auxiliary diode Da1And the third auxiliary diode Da3Also starts to conduct, the resonant inductor LrThe resonant capacitor Cr1And said resonant capacitor Cr2Starting to resonate, the resonant capacitor Cr1Is charged, the resonant capacitor Cr1Terminal voltage u ofCr1Starting from 0, the resonant capacitance C is gradually increasedr2Starting to discharge, the resonant capacitor Cr2Terminal voltage u ofCr2Gradually decreases from E and flows through the resonant inductor LrCurrent i ofLrStarting from 0 and increasing in reverse. When the terminal voltage u of the resonant capacitorr2Decreases to kE, flows through the resonant inductor LrCurrent i ofLrJust increases in the reverse direction to a forward maximum, after which the resonant inductance LrStarts to discharge, flows through the resonant inductor LrCurrent i ofLrGradually decrease, the resonance capacitance Cr1Continuing to charge the resonant capacitor Cr2Continuing to discharge until t6End of time, the resonant capacitor Cr2Terminal voltage u ofr2Reduced to equal 0, said resonant capacitance Cr1Terminal voltage u ofCr1Increases to E and flows through the resonant inductor LrCurrent i ofLrReverse direction is reduced to be equal to I2。
In the eighth mode of operation (corresponding to t in FIG. 4)6-t7Phase), please refer to fig. 3, fig. 4 and fig. 5(h) together, at t6At the moment, the second main switch S is opened by outputting a high-level pulse signal through a driving chip2. Due to the second main switch S2Before opening, with the second main switch S2The resonance capacitor C connected in parallelr2Has been reduced to 0, and thus, the second main switch S2Zero voltage turn-on is achieved. From t6At the beginning of the moment, the freewheeling diode D1Is conducted and flows through the resonant inductor LrCurrent i ofLrFrom I2Starts to decrease until t7At the end of the time, the current flows through the resonant inductor LrCurrent i ofLrReduced to 0, load current I0All flows through the freewheel diode D1And the auxiliary resonant circuit finishes the work. At the same time, at t7The first auxiliary switch S is switched off by outputting a low-level pulse signal through a driving chip at any momenta1Due to the first auxiliary switch S being turned offa1Before flowing through the first auxiliary switch Sa1Current i ofLrHas been reduced to 0, so that said first auxiliary switch Sa1Zero current turn-off is achieved.
At t7And after the moment is received, the working state of the single-phase circuit returns to the first working mode again, and the eight working modes are repeated to start the next working cycle. It should be noted that the operation mode of the single-phase current in the case that the load current is negative is similar to the above embodiment, and the detailed description is omitted here.
In the inverter circuit 100, when the primary winding n of the three-phase transformer is used as the primary winding n1When current flows through the primary winding n1The voltage value borne is assumed to be E, and the primary winding n1Through the second auxiliary diode Da2And the fourth auxiliary diode Da4(alternatively, the first auxiliary diode Da1And the third auxiliary diode Da3) Freewheeling flowing into the dc power supply 110 may cause the dc power supply 110 to fail to deliver energy to the three-phase load in the forward direction, which may result in a loss of duty cycle. Thus, at t0Time to t4Time t and5time to t7At the moment, the two segments of the auxiliary switch are in the conducting state,in order to reduce the loss of duty cycle, the auxiliary switches (the first auxiliary switch S) should be minimized in the control of the auxiliary resonant circuita1And said second auxiliary switch Sa2) The duty cycle of (c). In addition, the resonant inductor LrThe resonant capacitor Cr1And said resonant capacitor Cr2The value should be as small as possible to reduce the on-time of the auxiliary switch in each switching cycle, and thus to reduce the loss of duty cycle.
The embodiment of the utility model provides an inverter circuit, including the DC power supply, three auxiliary resonance circuit, three-phase inverter and the three-phase load that connect gradually, wherein, each auxiliary resonance circuit includes a resonance inductance, and three-phase inverter includes three bridge arm, and each bridge arm includes two main switch and two resonance capacitance, one parallelly connected has one on the main switch resonance capacitance, the resonance inductance on the three auxiliary resonance circuit is connected with the output of three bridge arm respectively, when the main switch needs the switching state, resonance inductance and/or resonance capacitance that are located same looks with the main switch produce the resonance, so that the main switch can realize that zero current turn-off and zero voltage switch on.
It should be noted that the above-described device embodiments are merely illustrative, where the units described as separate parts may or may not be physically separate, and the parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; within the idea of the invention, also technical features in the above embodiments or in different embodiments can be combined, steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.
Claims (10)
1. An inverter circuit, comprising:
a direct current power supply;
three auxiliary resonance circuits, three input ends of which are respectively connected with the output end of the direct current power supply, and each auxiliary resonance circuit comprises a resonance inductor;
the three-phase inverter is provided with three bridge arms, each bridge arm comprises two main switches and two resonant capacitors, one main switch is connected with one resonant capacitor in parallel, and the resonant inductors on the three auxiliary resonant circuits are respectively connected with the output ends of the three bridge arms;
the input end of the three-phase load is respectively connected with the three output ends of the three bridge arms; wherein,
when the main switch needs to switch the state, the resonance inductor and/or the resonance capacitor which are positioned on the same phase with the main switch generate resonance, so that the main switch realizes zero current turn-off and zero voltage turn-on.
2. The inverter circuit according to claim 1,
any of the bridge arms includes: the resonant inductor comprises a first main switch and a second main switch, wherein an emitter of the first main switch is connected with a collector of the second main switch, and one end of the resonant inductor is connected between the emitter of the first main switch and the collector of the second main switch.
3. The inverter circuit according to claim 2,
the auxiliary resonant circuit in the same phase as the first main switch and the second main switch further includes:
the unidirectional transformer comprises a primary winding and a secondary winding, and one end of the secondary winding is connected with the other end of the resonant inductor;
a first auxiliary switch, an emitter of which is connected with a cathode of the direct current power supply, and a collector of which is connected with the other end of the secondary winding;
and a second auxiliary switch having an emitter connected to the collector of the first auxiliary switch and a collector connected to the anode of the dc power supply.
4. The inverter circuit according to claim 3,
the auxiliary resonant circuit in the same phase as the first main switch and the second main switch further includes:
the anode of the first auxiliary diode is connected with one end of the primary winding, and the cathode of the first auxiliary diode is connected with the anode of the direct-current power supply;
the anode of the second auxiliary diode is connected with the other end of the primary winding, and the cathode of the second auxiliary diode is connected with the anode of the direct-current power supply;
the anode of the third auxiliary diode is connected with the cathode of the direct-current power supply, and the cathode of the third auxiliary diode is connected with the other end of the primary winding;
and the anode of the fourth auxiliary diode is connected with the cathode of the direct-current power supply, and the cathode of the fourth auxiliary diode is connected with one end of the primary winding.
5. The inverter circuit according to claim 4,
and a freewheeling diode is reversely connected in parallel between the collectors and the emitters of the first main switch and the second main switch.
6. The inverter circuit according to claim 5,
the first main switch and the second main switch are insulated gate bipolar transistors.
7. The inverter circuit according to claim 4,
and a reverse parallel diode is reversely connected between the collector and the emitter of the first auxiliary switch and the second auxiliary switch in parallel.
8. The inverter circuit according to claim 7,
the first auxiliary switch and the second auxiliary switch are insulated gate bipolar transistors.
9. The inverter circuit according to any one of claims 3 to 8, wherein the three-phase inverter further comprises:
and the output end of the driving chip is respectively connected with the bases of the first main switch, the second main switch, the first auxiliary switch and the second auxiliary switch and is used for outputting a pulse signal to control the on-off of the first main switch, the second main switch, the first auxiliary switch and/or the second auxiliary switch.
10. The inverter circuit according to any one of claims 3 to 8,
each phase load in the three-phase load comprises a load capacitor and a load inductor, and the load capacitor is connected with the load inductor in series.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020803918.0U CN212367151U (en) | 2020-05-14 | 2020-05-14 | Inverter circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020803918.0U CN212367151U (en) | 2020-05-14 | 2020-05-14 | Inverter circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212367151U true CN212367151U (en) | 2021-01-15 |
Family
ID=74149794
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020803918.0U Active CN212367151U (en) | 2020-05-14 | 2020-05-14 | Inverter circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212367151U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111555648A (en) * | 2020-05-14 | 2020-08-18 | 深圳市德兰明海科技有限公司 | Inverter circuit |
| CN117040288A (en) * | 2023-10-08 | 2023-11-10 | 深圳市德兰明海新能源股份有限公司 | Direct-current boost conversion circuit and energy storage power supply |
-
2020
- 2020-05-14 CN CN202020803918.0U patent/CN212367151U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111555648A (en) * | 2020-05-14 | 2020-08-18 | 深圳市德兰明海科技有限公司 | Inverter circuit |
| CN117040288A (en) * | 2023-10-08 | 2023-11-10 | 深圳市德兰明海新能源股份有限公司 | Direct-current boost conversion circuit and energy storage power supply |
| CN117040288B (en) * | 2023-10-08 | 2024-01-12 | 深圳市德兰明海新能源股份有限公司 | Direct-current boost conversion circuit and energy storage power supply |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8441812B2 (en) | Series resonant converter having a circuit configuration that prevents leading current | |
| CN102624266B (en) | Three-level inverter circuit | |
| CN108123605B (en) | Control method of power conversion circuit and related power conversion circuit | |
| US20120187879A1 (en) | Zero-voltage-transition soft switching converter | |
| JPWO2008020629A1 (en) | Isolated step-up push-pull soft switching DC / DC converter | |
| CN110190752B (en) | Bidirectional CLLLC-DCX resonant converter and control method thereof | |
| CN104953846A (en) | Wide-range input efficient direct current-direct current converter | |
| CN114465479A (en) | Three-port bidirectional DC/DC converter soft switching circuit and device thereof | |
| CN212367151U (en) | Inverter circuit | |
| CN215934730U (en) | DC-DC converter with high step-up ratio | |
| CN113395005B (en) | Inverter circuit, driving method thereof, multiphase inverter circuit and inverter | |
| CN113541486B (en) | Interleaved diode capacitor network high-gain ZVT (zero voltage zero volt) direct current converter and auxiliary circuit | |
| CN106655792B (en) | Asymmetric half-bridge flyback circuit | |
| CN110912407B (en) | Wide-range high-frequency direct current conversion device | |
| CN112953288A (en) | Modulation method for resonant direct-current link soft switching inverter | |
| CN111555648A (en) | Inverter circuit | |
| CN109412447B (en) | Phase-shifting three-phase high-frequency chain matrix inverter topological structure and modulation method | |
| CN217931786U (en) | Phase compensation sampling circuit | |
| CN113131750B (en) | Secondary-side clamping type phase-shifted full-bridge converter | |
| CN110729913B (en) | Single-stage high-gain five-switch Boost type inverter | |
| CN108599538B (en) | Off-line output rectifier diode peak voltage suppression circuit | |
| CN114915173A (en) | Flexible cutting type power converter | |
| CN113659822A (en) | Method for reducing loss of soft switching power converter based on saturated inductor | |
| CN113507229A (en) | Wide-input step-down inversion system based on switched capacitor network and control method | |
| CN111600490A (en) | DAB auxiliary loop and control time sequence applied to power electronic transformer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address | ||
| CP03 | Change of name, title or address |
Address after: 518000 19th floor, building 1, kaidar group center building, No. 168, Tongsha Road, Xinwei community, Xili street, Nanshan District, Shenzhen, Guangdong Patentee after: Shenzhen Delian Minghai New Energy Co.,Ltd. Address before: 701-3, building 2, kaidar group center building, 168 Tongsha Road, Xili street, Nanshan District, Shenzhen City, Guangdong Province Patentee before: Shenzhen Poweroak Newener Co.,Ltd. |