阅读说明：本技术 短路保护电路及短路保护系统 (Short-circuit protection circuit and short-circuit protection system ) 是由 赵辉 敬强 于 2018-09-04 设计创作，主要内容包括：本申请公开了一种短路保护电路及短路保护系统,该短路保护电路的过流保护单元包括第一可控开关、第二可控开关以及第一电阻、第二电阻,第一可控开关的控制端与第一电阻的第二端、第二可控开关的第一端及第二电压端连接,第一可控开关的第一端连接第二可控开关的控制端及第二电阻的第一端,第一可控开关的第二端与第一电阻的第一端、第一电压端及第一输出端连接,第二可控开关的第二端连接第二电阻的第二端及第二输出端。本申请的短路保护电路能使发生短路的电源单元不吸取第一输出端及第二输出端的电流,保障负载正常工作,提高系统的可靠性。(The application discloses short-circuit protection circuit and short-circuit protection system, this short-circuit protection circuit's overcurrent protection unit includes first controllable switch, second controllable switch and first resistance, second resistance, the control end of first controllable switch and the second end of first resistance, the first end and the second voltage end of second controllable switch are connected, the control end of second controllable switch and the first end of second resistance are connected to the first end of first controllable switch, the second end and the first end of first resistance, first voltage end and the first output of first controllable switch are connected, the second end and the second output of second resistance are connected to the second end of second controllable switch. The short-circuit protection circuit can enable the power supply unit with the short circuit not to absorb the current of the first output end and the second output end, guarantee the normal work of the load and improve the reliability of the system.)

1. A short-circuit protection circuit, comprising:

the power supply unit comprises a first voltage end and a second voltage end and is used for providing working voltage;

a first output terminal and a second output terminal for connection with a load;

the overcurrent protection unit is connected with the first voltage end and the second voltage end of the power supply unit and is used for switching on circuits between the power supply unit and the first output end and between the power supply unit and the second output end respectively when the power supply unit works normally, or switching off the circuits between the power supply unit and the first output end or between the power supply unit and the second output end when the power supply unit is in short circuit;

the overcurrent protection unit comprises a first controllable switch, a second controllable switch, a first resistor and a second resistor, wherein the control end of the first controllable switch is connected with the second end of the first resistor, the first end of the second controllable switch and the second voltage end, the first end of the first controllable switch is connected with the control end of the second controllable switch and the first end of the second resistor, the second end of the first controllable switch is connected with the first end of the first resistor, the first voltage end and the first output end, and the second end of the second controllable switch is connected with the second end of the second resistor and the second output end.

2. The short-circuit protection circuit according to claim 1, wherein the over-current protection unit further comprises a fuse, a first end of the fuse is connected to the second end of the second resistor and the second end of the second controllable switch, and the second end of the fuse is connected to the second output terminal.

3. The short-circuit protection circuit according to claim 2, wherein the over-current protection unit further comprises a third resistor and a fourth resistor, a first end of the third resistor is connected to the first end of the first controllable switch, a second end of the third resistor is connected to the first end of the second resistor and the control end of the second controllable switch, a first end of the fourth resistor is connected to the second end of the first resistor and the control end of the first controllable switch, and a second end of the fourth resistor is connected to the first end of the second controllable switch and the second voltage end.

4. The short-circuit protection circuit according to claim 3, wherein the over-current protection unit further comprises a fifth resistor, a first end of the fifth resistor is connected to a second end of the fourth resistor, and a second end of the fifth resistor is connected to the first end of the second controllable switch and the second voltage end.

5. The short-circuit protection circuit according to claim 3 or 4, wherein the over-current protection unit further comprises a first filter capacitor, a first end of the first filter capacitor is connected to the first end of the first resistor and the first voltage end of the power supply unit, and a second end of the first filter capacitor is connected to the first end of the second controllable switch and the second voltage end of the power supply unit.

6. The short-circuit protection circuit of claim 5, wherein the over-current protection unit further comprises a second filter capacitor, a first end of the second filter capacitor is connected to the second end of the fuse and the second output terminal, and a second end of the second filter capacitor is connected to the second end of the first controllable switch and the first output terminal.

7. The short-circuit protection circuit of claim 6, wherein the first filter capacitor is an electrolytic capacitor and the second filter capacitor is a ceramic capacitor.

8. The short-circuit protection circuit according to claim 1, wherein the power supply unit further comprises a current source, a transformer, a first diode, and a second diode, the transformer comprises a primary winding and a secondary winding, the primary winding of the transformer is connected to the current source, the secondary winding of the transformer comprises a first secondary winding and a second secondary winding, an anode of the first diode is connected to the different-name terminal of the first secondary winding, a cathode of the first diode is connected to a cathode of the second diode and connected to the first voltage terminal, an anode of the second diode is connected to the same-name terminal of the second secondary winding, and the second voltage terminal is connected to the same-name terminal of the first secondary winding and the different-name terminal of the second secondary winding.

9. The dc power supply circuit according to claim 1, wherein the first controllable switch is a P-channel field effect transistor, and the control terminal, the first terminal and the second terminal of the first controllable switch correspond to the gate, the drain and the source of the P-channel field effect transistor, respectively; the second controllable switch is an N-channel field effect transistor, and a control end, a first end and a second end of the second controllable switch respectively correspond to a grid electrode, a drain electrode and a source electrode of the N-channel field effect transistor.

10. A short-circuit protection system, comprising at least two short-circuit protection circuits connected in parallel, each of the short-circuit protection circuits comprising:

the power supply unit comprises a first voltage end and a second voltage end and is used for providing working voltage;

a first output terminal and a second output terminal for connection with a load;

the overcurrent protection unit is connected with the first voltage end and the second voltage end of the power supply unit and is used for switching on circuits between the power supply unit and the first output end and between the power supply unit and the second output end respectively when the power supply unit works normally, or switching off the circuits between the power supply unit and the first output end or between the power supply unit and the second output end when the power supply unit is in short circuit;

the overcurrent protection unit comprises a first controllable switch, a second controllable switch, a first resistor and a second resistor, wherein the control end of the first controllable switch is connected with the second end of the first resistor, the first end of the second controllable switch and the second voltage end, the first end of the first controllable switch is connected with the control end of the second controllable switch and the first end of the second resistor, the second end of the first controllable switch is connected with the first end of the first resistor, the first voltage end and the first output end, and the second end of the second controllable switch is connected with the second end of the second resistor and the second output end.

Technical Field

The present disclosure relates to short-circuit protection technologies, and particularly to a short-circuit protection circuit and a short-circuit protection system.

Background

In some high-power direct-current power supply power utilization scenes, when a single direct-current power supply module cannot provide enough power, a plurality of modules need to be connected in parallel, and 1-2 modules are generally redundantly and additionally configured in parallel connection. However, when a short circuit occurs in the dc power module in the system, the short-circuited dc power module may draw a voltage to the output bus, so that the voltage output to the load may be pulled down, resulting in a great reduction in system reliability.

Therefore, it is necessary to provide a short-circuit protection circuit and a short-circuit protection system to solve the above technical problems.

Disclosure of Invention

The application mainly provides a short-circuit protection circuit and a short-circuit protection system, and the short-circuit protection circuit can improve the reliability of the system.

In order to solve the above technical problem, a first technical solution adopted by the present application is to provide a short-circuit protection circuit, including: the power supply unit comprises a first voltage end and a second voltage end and is used for providing working voltage; a first output terminal and a second output terminal for connection with a load; the overcurrent protection unit is connected with the first voltage end and the second voltage end of the power supply unit and is used for switching on circuits between the power supply unit and the first output end and between the power supply unit and the second output end respectively when the power supply unit works normally, or switching off the circuits between the power supply unit and the first output end or between the power supply unit and the second output end when the power supply unit is in short circuit; the overcurrent protection unit comprises a first controllable switch, a second controllable switch, a first resistor and a second resistor, wherein the control end of the first controllable switch is connected with the second end of the first resistor, the first end of the second controllable switch is connected with the second voltage end, the first end of the first controllable switch is connected with the control end of the second controllable switch and the first end of the second resistor, the second end of the first controllable switch is connected with the first end of the first resistor, the first voltage end and the first output end, and the second end of the second controllable switch is connected with the second end of the second resistor and the second output end.

In order to solve the above technical problem, a second technical solution adopted by the present application is to provide a short-circuit protection system, where the short-circuit protection system includes at least two short-circuit protection circuits connected in parallel, and each short-circuit protection circuit includes: the power supply unit comprises a first voltage end and a second voltage end and is used for providing working voltage; a first output terminal and a second output terminal for connection with a load; the overcurrent protection unit is connected with the first voltage end and the second voltage end of the power supply unit and is used for switching on circuits between the power supply unit and the first output end and between the power supply unit and the second output end respectively when the power supply unit works normally, or switching off the circuits between the power supply unit and the first output end or between the power supply unit and the second output end when the power supply unit is in short circuit; the overcurrent protection unit comprises a first controllable switch, a second controllable switch, a first resistor and a second resistor, wherein the control end of the first controllable switch is connected with the second end of the first resistor, the first end of the second controllable switch is connected with the second voltage end, the first end of the first controllable switch is connected with the control end of the second controllable switch and the first end of the second resistor, the second end of the first controllable switch is connected with the first end of the first resistor, the first voltage end and the first output end, and the second end of the second controllable switch is connected with the second end of the second resistor and the second output end.

The beneficial effect of this application is: different from the situation in the prior art, the overcurrent protection unit in the short-circuit protection circuit of the present application includes a first controllable switch, a second controllable switch, a first resistor, and a second resistor, wherein a control terminal of the first controllable switch is connected to a second terminal of the first resistor, a first terminal of the second controllable switch and a second voltage terminal, a first terminal of the first controllable switch is connected to a control terminal of the second controllable switch and a first terminal of the second resistor, a second terminal of the first controllable switch is connected to a first terminal of the first resistor, a first voltage terminal and a first output terminal, and a second terminal of the second controllable switch is connected to a second terminal of the second resistor and a second output terminal. The overcurrent protection unit can timely disconnect the circuit between the power supply unit and the first output end or between the power supply unit and the second output end when the power supply unit is in a short circuit, the short-circuited power supply unit cannot absorb the current of the first output end and the current of the second output end, and therefore the voltage between the first output end and the second output end connected with a load is normal, and the reliability of a system is improved.

Drawings

Fig. 1 is a schematic structural diagram of a short-circuit protection circuit provided in the present application;

FIG. 2 is a circuit schematic of a first embodiment of a short-circuit protection circuit provided herein;

FIG. 3 is a circuit schematic of a second embodiment of a short-circuit protection circuit provided herein;

fig. 4 is a schematic structural diagram of a short-circuit protection system provided in the present application.

Detailed Description

In order to make the purpose, technical solution and technical effects of the present application clearer and clearer, the present application is further described in detail below, and it should be understood that the specific embodiments described herein are only used for explaining the present application and are not used for limiting the present application.

In some high-power direct-current power supply power utilization scenes, when a single direct-current power supply module cannot meet the power requirement, a plurality of modules need to be connected in parallel, and 1-2 modules are generally redundantly and additionally configured in parallel connection. However, when the dc power module in the system is short-circuited, the voltage output to the load will be pulled down, resulting in a great reduction in system reliability. In order to solve the technical problem, the first controllable switch, the second controllable switch, the first resistor and the second resistor are arranged in the overcurrent protection unit, when the power supply unit is in a short circuit, the overcurrent protection unit is used for timely disconnecting a circuit between the power supply unit and the first output end or between the power supply unit and the second output end, and therefore the voltage between the first output end and the second output end connected with the load is guaranteed to be normal. Hereinafter, the present application will be described in detail with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a short-circuit protection circuit according to the present application. As shown in fig. 1, the short-circuit protection circuit includes a power supply unit 11, an overcurrent protection unit 12, a first output terminal 13, and a second output terminal 14. The first output end 13 and the second output end 14 are used for connecting with a load 15 or a back-end circuit and outputting a voltage required by the operation of the load 15 or the back-end circuit; the power supply unit 11 includes a first voltage end 111 and a second voltage end 112, and the power supply unit 11 provides the operating voltage required by the overcurrent protection unit 12 and the load 15 or the back-end circuit through the first voltage end 111 and the second voltage end 112; the overcurrent protection unit 12 is connected to the first voltage terminal 111 and the second voltage terminal 112 of the power supply unit 11, and is configured to turn on a circuit between the power supply unit 11 and the first output terminal 13 and the second output terminal 14 respectively when the power supply unit 11 is in normal operation, or turn off a circuit between the power supply unit 11 and the first output terminal 13 or turn off a circuit between the power supply unit 11 and the second output terminal 14 when the power supply unit 11 is in a short circuit, so that the short-circuited power supply unit 11 cannot draw currents of the first output terminal 13 and the second output terminal 14, and can ensure that the voltage between the first output terminal 13 and the second output terminal 14 connected to the load 15 is normal.

Specifically, the overcurrent protection unit 12 includes a first controllable switch 121, a second controllable switch 122, a first resistor 123 and a second resistor 124, a control end a of the first controllable switch 121 is connected to a second end of the first resistor 123, a first end e of the second controllable switch 122 and a second voltage end 112, a first end b of the first controllable switch 121 is connected to a control end g of the second controllable switch 122 and a first end of the second resistor 124, a second end c of the first controllable switch 121 is connected to a first end of the first resistor 123, a first voltage end 111 and a first output end 13, and a second end f of the second controllable switch 122 is connected to a second end of the second resistor 124 and a second output end 14.

In this embodiment, the voltage between the first output terminal 13 and the second output terminal 14 is a dc voltage, and the first output terminal 13 and the second output terminal 14 are respectively connected to the positive terminal and the negative terminal of the load 15.

When the power supply unit 11 normally works, the overcurrent protection unit 12 turns on a circuit between the power supply unit 11 and the first output terminal 13 and the second output terminal 14, and outputs a working voltage required by the load 15 through the first output terminal 13 and the second output terminal 14, specifically, when the power supply unit 11 normally works, a voltage across the first resistor 123 is a turn-on voltage of the first controllable switch 121, that is, the first controllable switch 121 is in a turn-on state at this time, and a voltage across the second resistor 124 is a turn-on voltage of the second controllable switch 122, that is, the second controllable switch 122 is in a turn-on state at this time; when the power unit 11 is short-circuited, the over-current protection unit 12 disconnects the circuit between the power unit 11 and the first output terminal 13 or disconnects the circuit between the power unit 11 and the second output terminal 14, specifically, when the power unit 11 is short-circuited, the voltage across the first resistor 123 is approximately zero volts, that is, the voltage across the first resistor 123 is lower than the on-voltage of the first controllable switch 121, the first controllable switch 121 is in an off state, the voltage across the second resistor 124 is approximately zero volts, that is, the second controllable switch 122 is also in an off state, then the power unit 11 with the short-circuit will not draw the currents of the first output terminal 13 and the second output terminal 14, and the voltage across the load 15 will not be pulled down.

In this embodiment, the first controllable switch 121, the second controllable switch 122, the first resistor 123, and the second resistor 124 are disposed in the overcurrent protection unit 12, so that the voltage across the load 15 is not pulled down when the power supply unit 11 is short-circuited, and the reliability of the system is improved.

Fig. 2 is a schematic circuit diagram of a short-circuit protection circuit according to a first embodiment of the present disclosure. As shown in fig. 2, the short-circuit protection circuit includes a power supply unit 201, an over-current protection unit 202, a first output terminal DCVOUT + and a second output terminal DCVOUT-. The power unit 201 includes a current source I, a transformer T, a first diode D1 and a second diode D2, the transformer T includes a primary winding T0 and a secondary winding, the primary winding T0 of the transformer T is connected to the current source I, the secondary winding of the transformer T includes a first secondary winding T1 and a second secondary winding T2, an anode of the first diode D1 is connected to a different-name end of the first secondary winding T1, a cathode of the first diode D1 is connected to a cathode of the second diode D2 and to a first voltage end M, an anode of the second diode D2 is connected to a same-name end of the second secondary winding T2, and a second voltage end H is connected to the same-name end of the first secondary winding T1 and the different-name end of the second secondary winding T2. Specifically, when the first diode D1 is turned on and the second diode D2 is turned off in the reverse direction, the dotted terminal of the first secondary winding T1 is connected to the second voltage terminal H, and the dotted terminal of the first secondary winding T1 is connected to the first voltage terminal M, so as to provide the operating voltage to the load or the back-end circuit through the first voltage terminal M and the second voltage terminal H; when the first diode D1 is turned off in the reverse direction and the second diode D2 is turned on, the dotted terminal of the second sub-winding T2 is connected to the first voltage terminal M, and the dotted terminal of the second sub-winding T2 is connected to the second voltage terminal H, so that the operating voltage is provided to the load or the back-end circuit through the first voltage terminal M and the second voltage terminal H.

The overcurrent protection unit 202 includes a first controllable switch Q1, a second controllable switch Q2, a fuse F1, and first to fourth resistors R1, R2, R3, R4. A control end of the first controllable switch Q1 is connected to the second end of the first resistor R1 and the first end of the fourth resistor R4, a second end of the first controllable switch Q1 is connected to the first end of the first resistor R1, the first voltage end M and the first output end DCVOUT +, the first end of the first controllable switch Q1 is connected to the first end of the third resistor R3, a control end of the second controllable switch Q2 is connected to the second end of the third resistor R3 and the first end of the second resistor R2, the first end of the second controllable switch Q2 is connected to the second end of the fourth resistor R4 and the second voltage end H, the second end of the second controllable switch Q2 is connected to the second end of the second resistor R2 and the first end of the fuse F1, and the second end of the F1 is connected to the second output end DCVOUT-.

In this embodiment, the first controllable switch Q1 is a P-channel fet, and the control terminal, the first terminal and the second terminal of the first controllable switch Q1 correspond to the gate, the drain and the source of the P-channel fet, respectively; the second controllable switch Q2 is an N-channel fet, and the control terminal, the first terminal, and the second terminal of the second controllable switch Q2 correspond to the gate, the drain, and the source of the N-channel fet, respectively. In other embodiments, the first controllable switch and the second controllable switch may also be other types of transistors, and are not limited herein.

In this embodiment, the over-current protection unit 202 further includes a first filter capacitor C1, a first end of the first filter capacitor C1 is connected to a first end of the first resistor R1 and a first voltage end M of the power supply unit 201, and a second end of the first filter capacitor C1 is connected to a first end of the second controllable switch Q2, a second end of the fourth resistor R4 and a second voltage end H of the power supply unit 201. Specifically, the first filter capacitor C1 is an electrolytic capacitor, and the electrolytic capacitor can filter the voltage signals output by the first output terminal M and the second output terminal N.

When the first diode D1 is turned on, the second diode D2 is turned off in the reverse direction, or the first diode D1 is turned off in the reverse direction, and the second diode D2 is turned on, that is, the power supply unit 201 normally operates at this time, the voltage across the first resistor R1 is the on voltage of the first controllable switch Q1, and the voltage across the second resistor R2 is the on voltage of the second controllable switch Q2, that is, the first controllable switch Q1 and the second controllable switch Q2 are both in the on state, at this time, the second resistor R2 and the third resistor R3 in the overcurrent protection unit 202 are connected in series, the first resistor R1 and the fourth resistor R4 are connected in series, and the first controllable switch Q1, the second controllable switch Q2, and the fuse F1 are all in the on state. The first voltage end M and the second voltage end H output the voltage signal of the power supply unit 201 to the overcurrent protection unit 202, the first filter capacitor C1 filters the voltage signal, and the overcurrent protection unit 202 transmits the filtered voltage signal to the first output terminal DCVOUT + and the second output terminal DCVOUT-, and the load or the back-end circuit connected to the first output terminal DCVOUT + and the second output terminal DCVOUT-normally operates.

When the power supply unit 201 is short-circuited, the first diode D1 and the second diode D2 are broken down, the voltage across the first resistor R1 is close to zero volts, which is lower than the turn-on voltage of the first controllable switch Q1, the first controllable switch Q1 is turned off, the voltage across the second resistor R2 is close to zero volts, which is lower than the turn-on voltage of the second controllable switch Q2, and the second controllable switch Q2 is turned off, so that the short-circuited power supply unit 201 cannot draw the current of the first output terminal DCVOUT + and the second output terminal DCVOUT-, and the voltage across the load connected to the first output terminal DCVOUT + and the second output terminal DCVOUT-is not pulled down.

Even if the first controllable switch Q1 and/or the second controllable switch Q2 are not turned off in time due to a fault, when the current passing through the fuse F1 in the overcurrent protection unit 202 is large to a predetermined value, the fuse F1 is blown to disconnect the circuit between the power supply unit 201 and the load, which is short-circuited, so as to ensure the normal operation of the load, and the reliability of the system can be further improved by providing the fuse F1.

In this embodiment, the first terminal of the fuse F1 is connected to the second terminal of the second controllable switch Q2, the second terminal of the fuse F1 is connected to the second output DCVOUT-, and in other embodiments, the first terminal of the fuse F1 is connected to the second terminal of the first controllable switch Q1, and the second terminal of the fuse F1 is connected to the first output DCVOUT +.

In this embodiment, the first controllable switch Q1, the second controllable switch Q2, and the fuse F1 are disposed in the overcurrent protection unit 202, so that the voltage across the load is not pulled down when the power supply unit 201 is short-circuited, and the reliability of the system is improved.

Fig. 3 is a schematic circuit diagram of a short-circuit protection circuit according to a second embodiment of the present disclosure. As shown in fig. 3, the short-circuit protection circuit includes a power supply unit 301, an over-current protection unit 302, a first output terminal DCVOUT +, and a second output terminal DCVOUT-. The difference from the previous embodiment is that in the previous embodiment, the overcurrent protection unit includes first to fourth resistors and a first filter capacitor, and the overcurrent protection unit in this embodiment includes first to fifth resistors, a first filter capacitor, and a second filter capacitor.

Specifically, in this embodiment, the overcurrent protection unit further includes a fifth resistor R5 and a second filter capacitor C2, a first end of the fifth resistor R5 is connected to a second end of the fourth resistor R4, and a second end of the fifth resistor R5 is connected to a first end of the second controllable switch Q2, a second end of the first filter capacitor C1, and a second voltage end H; a first terminal of the second filter capacitor C2 is connected to the second terminal of the fuse F1 and the second output terminal DCVOUT-, and a second terminal of the second filter capacitor C2 is connected to the second terminal of the first controllable switch Q1 and the first output terminal DCVOUT +.

In this embodiment, the fifth resistor R5 is connected in series to the branch where the first resistor R1 and the fourth resistor R4 are located, so as to increase the voltage endurance; the first filter capacitor C1 is an electrolytic capacitor, and firstly carries out primary filtering processing on the voltage signal, and then carries out secondary filtering processing on the voltage signal by the second filter capacitor C2, so that a better filtering effect is achieved, and the voltage signal with better performance is obtained. The second filter capacitor C2 in this embodiment is a ceramic capacitor, but may be other types of filter capacitors in other embodiments, and is not limited herein.

Therefore, the overcurrent protection unit in the short-circuit protection circuit of the present application includes a first controllable switch, a second controllable switch, a first resistor, and a second resistor, wherein a control terminal of the first controllable switch is connected to a second terminal of the first resistor, a first terminal of the second controllable switch and a second voltage terminal, a first terminal of the first controllable switch is connected to a control terminal of the second controllable switch and a first terminal of the second resistor, a second terminal of the first controllable switch is connected to a first terminal of the first resistor, a first voltage terminal and a first output terminal, and a second terminal of the second controllable switch is connected to a second terminal of the second resistor and a second output terminal. The overcurrent protection unit can timely disconnect the circuit between the power supply unit and the first output end or between the power supply unit and the second output end when the power supply unit is in a short circuit, the short-circuited power supply unit cannot absorb the current of the first output end and the current of the second output end, and therefore the voltage between the first output end and the second output end connected with a load is normal, and the reliability of a system is improved.

Please refer to fig. 4, which is a schematic structural diagram of an embodiment of a short-circuit protection system according to the present application. The short-circuit protection system comprises at least two short-circuit protection circuits connected in parallel, wherein each short-circuit protection circuit comprises: the power supply unit comprises a first voltage end and a second voltage end and is used for providing working voltage; a first output terminal and a second output terminal for connection with a load; the overcurrent protection unit is connected with the first voltage end and the second voltage end of the power supply unit and is used for switching on circuits between the power supply unit and the first output end and between the power supply unit and the second output end respectively when the power supply unit works normally, or switching off the circuits between the power supply unit and the first output end or between the power supply unit and the second output end when the power supply unit is in short circuit; the overcurrent protection unit comprises a first controllable switch, a second controllable switch, a first resistor and a second resistor, wherein the control end of the first controllable switch is connected with the second end of the first resistor, the first end of the second controllable switch is connected with the second voltage end, the first end of the first controllable switch is connected with the control end of the second controllable switch and the first end of the second resistor, the second end of the first controllable switch is connected with the first end of the first resistor, the first voltage end and the first output end, and the second end of the second controllable switch is connected with the second end of the second resistor and the second output end.

In this embodiment, the short-circuit protection system includes a first short-circuit protection circuit, a second short-circuit protection circuit, and up to an nth short-circuit protection circuit, which are connected in parallel, and the N short-circuit protection circuits include redundant short-circuit protection circuits with multiple configurations, for example, the nth short-circuit protection circuit is a redundant short-circuit protection circuit with multiple configurations, when a power unit of one short-circuit protection circuit among the other N-1 short-circuit protection circuits is short-circuited, assuming that the power unit of the second short-circuit protection circuit is short-circuited, a first controllable switch and a second controllable switch in an over-current protection unit of the second short-circuit protection circuit are turned off or a fuse is turned off, so that the second short-circuit protection circuit cannot output a voltage signal to the load, and the second short-circuit protection circuit cannot pull down voltages at two ends of the load, thereby ensuring normal operation of the load. The over-current protection unit in each short-circuit protection circuit is the over-current protection unit in any one of the above embodiments.

In one embodiment, the short-circuit protection system comprises a first short-circuit protection circuit to a fifth short-circuit protection circuit connected in parallel, wherein the fifth short-circuit protection circuit is a redundant multi-configuration short-circuit protection circuit, and a system output bus + and a system output bus-are used for connecting two ends of a load. When the power supply units work normally, working voltage is provided for the load through the first short-circuit protection circuit to the fourth short-circuit protection circuit; when a power supply unit of one of the first to fourth short-circuit protection circuits is short-circuited, for example, when the power supply unit of the fourth short-circuit protection circuit is short-circuited, at this time, the first controllable switch and the second controllable switch of the overcurrent protection unit in the fourth short-circuit protection circuit are turned off, or the fuse is blown to disconnect the circuit between the power supply unit of the fourth short-circuit protection circuit and the load, that is, at this time, the fourth short-circuit protection circuit does not output voltage to the load, and at the same time, the fourth short-circuit protection circuit does not collapse the voltage at both ends of the load, and the multiple fifth short-circuit protection circuits output voltage to the load, that is, at this time, the first, second, third, and fifth short-circuit protection circuits provide working voltage to the load. The voltage of the load is not pulled down due to the short-circuited fourth short-circuit protection circuit, so that the normal work of the load can be guaranteed, and the reliability of the system is improved.

The beneficial effect of this application is: different from the situation in the prior art, the overcurrent protection unit in the short-circuit protection circuit of the present application includes a first controllable switch, a second controllable switch, a first resistor, and a second resistor, wherein a control terminal of the first controllable switch is connected to a second terminal of the first resistor, a first terminal of the second controllable switch and a second voltage terminal, a first terminal of the first controllable switch is connected to a control terminal of the second controllable switch and a first terminal of the second resistor, a second terminal of the first controllable switch is connected to a first terminal of the first resistor, a first voltage terminal and a first output terminal, and a second terminal of the second controllable switch is connected to a second terminal of the second resistor and a second output terminal. The overcurrent protection unit can timely disconnect the circuit between the power supply unit and the first output end or between the power supply unit and the second output end when the power supply unit is in a short circuit, the short-circuited power supply unit cannot absorb the current of the first output end and the current of the second output end, and therefore the voltage between the first output end and the second output end connected with a load is normal, and the reliability of a system is improved.

The above description is only an embodiment of the present application, and not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the specification and the drawings, or directly or indirectly applied to other related technical fields, are also included in the scope of the present application.