CN218161801U

CN218161801U - Over-current overvoltage surge suppressor

Info

Publication number: CN218161801U
Application number: CN202222044386.9U
Authority: CN
Inventors: 奚建勇
Original assignee: Wuxi Tianhe Electronic Co ltd
Current assignee: Wuxi Tianhe Electronic Co ltd
Priority date: 2022-08-04
Filing date: 2022-08-04
Publication date: 2022-12-27
Anticipated expiration: 2032-08-04

Abstract

The utility model provides an over-voltage surge suppressor for super-large current, its rated current is big, can be applicable to among the super-large current supply circuit, the effectual use cost that has practiced thrift, it includes surge suppression circuit, surge suppression circuit includes surge suppressor U1, surge suppressor U1 connects voltage surge absorption module respectively, sampling module and protection module, voltage surge absorption module includes IGBT1 to IGBT5 pipe, surge suppressor U1's 3, 4 pin voltage is through R4, input amplifier U2 carries out current amplification after the R6 partial pressure, IGBT1 switches on to IGBT5 pipe this moment, the pressure drop grow, be in the enlarged state, absorb partly input voltage, thereby make output voltage keep at 36V, reach the mesh of suppressing the over-voltage surge, because the rated current of 5 parallel connection's IGBT pipe is big, therefore can be applicable to among the super-large current supply circuit, the effectual use cost that has practiced thrift.

Description

Over-current overvoltage surge suppressor

Technical Field

The utility model relates to a surge suppression circuit technical field specifically is an over-voltage surge suppressor of super large current.

Background

At present, the power supply system of electronic instruments in the fields of military industry, aviation and aerospace can generate overvoltage surges exceeding normal power supply voltage, and the main measure adopted at present is to additionally arrange an overvoltage surge suppressor in front of the instruments, regulate the surge voltage into normal voltage and supply power to loads. However, the MOS tube is adopted as a key component adjusting tube in the overvoltage surge suppressor, and the current and power capacity of the MOS tube is not large, so that the rated current of the MOS tube is limited. At present, rated current of an overvoltage surge suppressor in the market is about 20A at most, when current of a power supply bus exceeds 20A, a plurality of overvoltage surge suppressors need to be configured to respectively supply power to different loads, and therefore the circuit structure is complex and the required cost is high.

SUMMERY OF THE UTILITY MODEL

Less to current surge suppressor rated current, if match in being suitable for great supply current circuit, then need dispose a plurality ofly, lead to the circuit structure complicacy, problem with high costs, the utility model provides a super large current overvoltage surge suppressor, its rated current is big, can be applicable to among the super large current supply circuit, the effectual use cost that has practiced thrift.

The technical scheme is as follows: the utility model provides an excess current overvoltage surge suppressor which is including installing the surge suppression circuit in supply circuit, its characterized in that: the surge suppression circuit comprises a surge suppressor U1, the surge suppressor U1 is respectively connected with a voltage surge absorption module, a sampling module and a protection module, the voltage surge absorption module comprises an IGBT1 to an IGBT5 tube, gate poles of the IGBT1 to the IGBT5 tube are respectively connected with one ends of resistors R14 to R18, the other ends of the resistors R14 to R18 are connected with 2 and 6 pins of an amplifier U2 and one end of a resistor R5, emitting electrodes of the IGBT1 to the IGBT5 tube are connected with 5 pins of the amplifier U2, one end of a capacitor C8, the other end of the resistor R5, one end of a resistor R6, one end of a resistor RS and one end of the surge suppressor U1, the other ends of the resistors R6 and the other end of the resistor R13 are connected with one end of a capacitor C8 and a 15V voltage source, the other ends of the resistors R6 are connected with one end of a resistor R13 and one end of a resistor R4, the other end of the resistor R13 is connected with 1 pin of the amplifier U2, the other end of the resistor R4 is connected with the anode of a diode D2, one end of the resistor R7 and one end of the capacitor C4, the other end of the capacitor C3 and the other end of the capacitor C4 are connected with the ground.

It is further characterized in that: the sampling module comprises a resistor R1 to a resistor R3, one end of the resistor R1 is connected with the other end of the resistor RS, the 2 pin of the surge suppressor U1, one end of a capacitor C1 and a VOUT + voltage output end, the other end of the resistor R1 is connected with one end of a resistor R2, the other end of the resistor R2 is connected with one end of the resistor R3, one end of a capacitor C7 and the 1 pin of the surge suppressor U1, and the other end of the capacitor C7, the other end of the resistor R3 and the other end of the capacitor C1 are connected and then connected with a VOUT-voltage output end;

the protection module includes resistance R8, resistance R9, resistance R10 and resistance R12, resistance R8 one end connecting resistance R9 one end, resistance R9 other end connecting resistance R10 one end, electric capacity C8 one end and surge suppressor U1's 8 pins, resistance R10 other end connecting resistance R12 one end and surge suppressor U1's 7 pins, VOUT-voltage output is connected to the resistance R12 other end.

After the structure is adopted, the normal value of the voltage of the input end is 18VDC to 36VDC, when the surge suppressor U1 samples overvoltage surge, the output low voltage of the pins 3 and 4 of the surge suppressor U1, the voltage of the pins 3 and 4 of the surge suppressor U1 is divided by R4 and R6 and then is input into the amplifier U2 for current amplification, at the moment, the IGBT1 to the IGBT5 tubes are conducted, the voltage drop is increased, the amplification state is realized, and a part of input voltage is absorbed, so that the output voltage is kept at 36V, the purpose of suppressing the overvoltage surge is achieved, and the rated current of the 5 IGBT tubes connected in parallel is large, so that the power supply circuit can be suitable for an ultrahigh current power supply circuit, and the use cost is effectively saved.

Drawings

FIG. 1 is a circuit diagram of the overall structure of the present invention;

FIG. 2 is a waveform of an input voltage surge;

FIG. 3 is an output voltage waveform of an IGBT tube directly driven by an integrated circuit;

fig. 4 shows the waveform of the output voltage surge of the present invention.

Detailed Description

As shown in fig. 1, the over-current overvoltage surge suppressor includes a surge suppression circuit installed in a power supply circuit, specifically, the surge suppression circuit includes a surge suppressor U1, and the surge suppressor U1 is connected to a voltage surge absorption module, a sampling module, and a protection module, respectively. Specifically, the voltage surge absorption module comprises IGBT 1-IGBT 5 tubes, gate poles of the IGBT 1-IGBT 5 tubes are respectively connected with a resistor R14-a resistor R18 one end, the other ends of the resistor R14-the resistor R18 are connected with a 2 pin and a6 pin of an amplifier U2 and one end of a resistor R5, emitting electrodes of the IGBT 1-IGBT 5 tubes are connected with a5 pin of the amplifier U2, one end of a capacitor C8, the other end of the resistor R5, one end of a resistor R6, one end of a resistor RS and a 3 pin of a surge suppressor U1, the 3 and 4 pins of the amplifier U2 are connected with a 15V voltage source, the other end of the resistor R6 is connected with one end of a resistor R13 and one end of a resistor R4, the other end of the resistor R13 is connected with a 1 pin of the amplifier U2, the other end of the resistor R4 is connected with an anode of a diode D2, one end of the resistor R7 and a 4 pin of the surge suppressor U1, the anode of the diode D2 is connected with the other end of the capacitor C3 and the other end of the capacitor C4 is grounded.

The sampling module comprises a resistor R1 to a resistor R3, one end of the resistor R1 is connected with the other end of a resistor RS, 2 pins of a surge suppressor U1, one end of a capacitor C1 and a VOUT + voltage output end, the other end of the resistor R1 is connected with one end of a resistor R2, the other end of the resistor R2 is connected with one end of a resistor R3, one end of a capacitor C7 and 1 pin of the surge suppressor U1, and the other end of the capacitor C7, the other end of the resistor R3 and the other end of the capacitor C1 are connected with a VOUT-voltage output end. The output voltage is sampled and sent to the integrated surge suppressor U1 for comparison and operation, and the output voltage of the 3 and 4 pins is controlled, so that the working state of the IGBT tube is controlled, and the output voltage is kept in a normal state.

The protection module comprises a resistor R8, a resistor R9, a resistor R10 and a resistor R12, one end of the resistor R8 is connected with one end of the resistor R9, the other end of the resistor R9 is connected with one end of the resistor R10, one end of a capacitor C8 and 8 pins of a surge suppressor U1, the other end of the resistor R10 is connected with one end of the resistor R12 and 7 pins of the surge suppressor U1, and the other end of the resistor R12 is connected with a VOUT-voltage output end.

The other end of the capacitor R11 is connected with the cathode of the diode D3, the other end of the resistor R8, a VIN + voltage source and the collectors of the IGBT1 to IGBT5 tubes, the 12 pins of the surge suppressor U1 are connected with one end of the capacitor C5 and one end of the capacitor C6, the other end of the capacitor C5, the other end of the capacitor C6, the other end of the capacitor C8, the anode of the diode D1, the other end of the capacitor C2 and the anode of the diode D3, and then the VIN-voltage source is connected with the ground. The capacitor C5 plays a timing role, when the input overvoltage pulse time is more than 50mS, the input power supply is considered to be in fault, the surge suppressor U1 cuts off the output voltage between the 3 pins and the 4 pins according to the set value of the timing capacitor C5, so that the IGBT tube is in a cut-off state, the output voltage of the product is 0V, the product and the rear-stage load are protected, after a cooling period, the surge suppressor U1 can be restarted, the product is restarted to work, and the set value of C5 is 2.2uf.

The working principle of the utility model is as follows:

if surge suppressor U1's 3, 4 pin input voltage direct drive ICBT pipe, because voltage is higher, make that it is not high that its CE utmost point voltage drop control accuracy is when the IGBT pipe work is enlarged state, output voltage precision is relatively poor when consequently leading to the overvoltage surge to appear, the utility model discloses with surge suppressor U1's 3, 4 pin's output voltage, after resistance R4, R6 partial pressure, improved output voltage's control accuracy, simultaneously the utility model discloses the circuit adopts 5 IGBT pipes, and equivalent input capacitance is 75000pf (single IGBT pipe is 15000 pf), and the biggest input capacitance of general MOS pipe is thousands pf, and consequently 5 IGBT pipes's equivalent input capacitance has more than MOS pipe's input capacitance tens times, simultaneously because 3 of surge suppressor U1, the drive current of 4 pin is less, if direct drive IGBT pipe, and IGBT pipe G utmost point speed is slower, easily leads to the too slow problem of response speed. Therefore, the problem of too low response speed can be solved by switching in a large-current amplifier U2 (the model is OPA547, and the output driving current is 500 mA) and then driving an IGBT tube. Fig. 2 shows the waveform of an input overvoltage surge, and fig. 3 shows the waveform of an output voltage of an IGBT tube directly driven by an integrated circuit. It can be seen from the comparison of the two diagrams that when an overvoltage surge occurs, the IGBT cannot be immediately changed from the on state to the amplification state due to too slow response speed, so that the output voltage has an overshoot of about 8V, and at this time, the output voltage becomes about 43V, and the overshoot (too large output voltage) is very likely to damage the rear stage load, such as the DC/DC module, and in addition, the response recovery time is too long, which may additionally increase the power consumption of the IGBT. And figure 4 is the utility model discloses an output voltage waveform, its overshoot reduces to 0.2V, and response time also shortens greatly, therefore can satisfy the operation requirement.

While the component values are calculated as follows:

r6 ÷ (R6 + R4) × U43= UG, UG =8v, U43=14v, r4=3m Ω, then R6=3.9M Ω, where U43 is the output voltage of the 3, 4 pins of surge suppressor U1, and UG is the output voltage of amplifier U2 (i.e., the G-pole control voltage of the IGBT). The amplification factor of the amplifier U2 is 1, the IGBT1, the IGBT2, the IGBT3, the IGBT4 and the IGBT5 are IGBT tubes, 5 IGBT tubes are adopted to work in parallel, the rated current is enlarged, the model is PRHMB150A6A, and the main electrical parameters are as follows: the CE extreme voltage resistance is 600V, the current IC =150A, the power consumption PC =560W, the thermal resistance is theta thjc =0.22 ℃/W, and the highest working junction temperature is 150 ℃. Since five are used in parallel, the actual power consumption can reach PC =560 × 5=2800w. When overvoltage surge exists, the power consumption is the maximum, the product bears an overvoltage pulse of 80V/50mS every minute when in work, and the duty ratio D =50 multiplied by 10-3 ÷ 60=8.3 multiplied by 10-4. When an over-voltage pulse comes, the voltage borne by the IGBT tube is 80-36=44V, the total current is 60A, and the actual power consumption is 2640W. Each IGBT tube bears 528W of power, the current is 60/5 =12A, and the IGBT tubes work in a safe working area. Calculation of its junction temperature: tj = [ θ thjc × D + (1-D) Sthjc ] × PC + TC =141 ℃ <150 ℃. Therefore, the IGBT tube is safe and reliable to work at the moment.

The above description is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope of the present invention should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The utility model provides an excess current overvoltage surge suppressor which is including installing the surge suppression circuit in power supply circuit, its characterized in that: the surge suppression circuit comprises a surge suppressor U1, the surge suppressor U1 is respectively connected with a voltage surge absorption module, a sampling module and a protection module, the voltage surge absorption module comprises an IGBT1 to an IGBT5 tube, gate poles of the IGBT1 to the IGBT5 tube are respectively connected with one ends of resistors R14 to R18, the other ends of the resistors R14 to R18 are connected with 2 and 6 pins of an amplifier U2 and one end of a resistor R5, emitting electrodes of the IGBT1 to the IGBT5 tube are connected with 5 pins of the amplifier U2, one end of a capacitor C8, the other end of the resistor R5, one end of a resistor R6, one end of a resistor RS and one end of the surge suppressor U1, the other ends of the resistors R6 and the other end of the resistor R13 are connected with one end of a capacitor C8 and a 15V voltage source, the other ends of the resistors R6 are connected with one end of a resistor R13 and one end of a resistor R4, the other end of the resistor R13 is connected with 1 pin of the amplifier U2, the other end of the resistor R4 is connected with the anode of a diode D2, one end of the resistor R7 and one end of the capacitor C4, the other end of the capacitor C3 and the other end of the capacitor C4 are connected with the ground.

2. The extra-large current overvoltage surge suppressor according to claim 1, wherein: sampling module includes resistance R1 to resistance R3, resistance R1 one end is connected the resistance RS other end 2 pins, electric capacity C1 one end and VOUT + voltage output of surge suppressor U1, resistance R1 other end connecting resistance R2 one end, resistance R2 other end connecting resistance R3 one end, electric capacity C7 one end reach 1 pin of surge suppressor U1, VOUT-voltage output is connected after the electric capacity C7 other end, the resistance R3 other end, the electric capacity C1 other end link to each other.

3. The extra-large current overvoltage surge suppressor according to claim 2, characterized in that: the protection module includes resistance R8, resistance R9, resistance R10 and resistance R12, resistance R8 one end connecting resistance R9 one end, resistance R9 other end connecting resistance R10 one end, electric capacity C8 one end and surge suppressor U1's 8 pins, resistance R10 other end connecting resistance R12 one end and surge suppressor U1's 7 pins, VOUT-voltage output is connected to the resistance R12 other end.