A power protection circuit

Abstract

The embodiment of the present invention discloses a power protection circuit, including a first power detection circuit, a first power regulation circuit, a first control circuit and a first power device; the first power detection circuit is used to generate a shutdown signal of the first power device and output it from its signal output terminal when the power-consuming device is over-voltage or over-current; the first power regulation circuit is used to generate an opening signal of the first power device within a preset time according to the shutdown signal of the first power device and output it from its signal output terminal; the input terminal of the first control circuit is electrically connected to the signal output terminal of the first power detection circuit and the signal output terminal of the first power regulation circuit respectively, and the output terminal of the first control circuit is electrically connected to the first power device. The technical solution provided by the embodiment of the present invention realizes that when an internal short circuit occurs in the power-consuming device or the power exceeds the standard, the connection between the power-consuming device and the power supply device is quickly cut off, and when the power-consuming device recovers by itself, it can be connected to the device in a timely and fast manner to enable the normal operation of the system.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of equipment protection, and in particular to a power supply protection circuit. Background Art

[0002] In recent years, monitoring equipment, data transmission equipment, edge computing alarm equipment, etc. in the hazardous chemicals industry have become increasingly common in local applications of hazardous chemical sources, and the power supply safety and electricity use safety of the equipment should be paid attention to.

[0003] In the existing technology, in the need for safe electricity use and power supply systems, electrical equipment is generally connected to the power supply equipment through a fuse, and the power supply equipment generally adopts the connection method of intrinsically safe power supply. When some monitoring systems need to set up hundreds or even thousands of equipment points, the use of this connection method will cause problems such as complex construction and high cost. Moreover, when the electrical equipment is restored, it is difficult to quickly connect the electrical equipment to the power supply system in time. Summary of the invention

[0004] The embodiment of the present invention provides a power protection circuit to quickly cut off the connection between the power-consuming device and the power supply device when an internal short circuit or power exceeding the standard occurs in the power-consuming device. After the power-consuming device recovers, it can quickly access the device in time to ensure the normal operation of the system.

[0005] A power protection circuit provided by an embodiment of the present invention includes: a first power detection circuit, a first power regulation circuit, a first control circuit and a first power device;

[0006] The first power device is connected between a power supply device and a power-consuming device, and the power supply device outputs a power supply voltage to the power-consuming device;

[0007] The first power detection circuit comprises a power input terminal and a signal output terminal, the power input terminal of the first power detection circuit is connected to a first voltage, and the first power detection circuit is used to generate a shutdown signal of the first power device and output it from its signal output terminal when the power-consuming device is over-voltage or over-current;

[0008] The first power regulating circuit comprises a power input terminal and a signal output terminal, the power input terminal of the first power regulating circuit is connected to the first voltage, and the first power regulating circuit is used to generate a turn-on signal of the first power device within a preset time according to a turn-off signal of the first power device and output it from its output terminal;

[0009] The first control circuit includes an input end and an output end. The input end of the first control circuit is electrically connected to the output end of the first power detection circuit and the output end of the first power regulation circuit respectively. The output end of the first control circuit is electrically connected to the first power device.

[0010] Optionally, the first power detection circuit includes a current detection circuit, and the current detection circuit includes a first resistor, a second resistor, a third resistor and a first operational amplifier;

[0011] The first end of the first resistor is connected to the first voltage, the second end of the first resistor is electrically connected to the positive terminal of the first operational amplifier through the second resistor, the negative terminal of the first operational amplifier is grounded through the third resistor, the first voltage terminal of the first operational amplifier is connected to the first voltage, the second voltage terminal of the first operational amplifier is grounded, and the output terminal of the first operational amplifier is electrically connected to the input terminal of the first control circuit.

[0012] Optionally, the first power detection circuit further includes a voltage detection circuit, and the voltage detection circuit includes a fourth resistor, a fifth resistor, a first capacitor and a second operational amplifier;

[0013] The positive terminal of the second operational amplifier is connected to the second voltage, the negative terminal of the second operational amplifier is electrically connected to the second end of the fourth resistor, the first end of the fourth resistor is connected to the third voltage, the second end of the fourth resistor is grounded through the fifth resistor, and the first capacitor is connected in parallel to both ends of the fifth resistor;

[0014] A first voltage terminal of the second operational amplifier is connected to the first voltage, a second terminal of the second operational amplifier is grounded, and an output terminal of the second operational amplifier is electrically connected to an input terminal of the first control circuit.

[0015] Optionally, the first control circuit includes a sixth resistor and a third operational amplifier;

[0016] The first end of the sixth resistor is electrically connected to the positive terminal of the third operational amplifier, the second end of the sixth resistor is connected to the first voltage, the positive terminal of the third operational amplifier is electrically connected to the output terminal of the first operational amplifier and the output terminal of the second operational amplifier respectively, the negative terminal of the third operational amplifier is connected to the second voltage, the first voltage terminal of the third operational amplifier is connected to the first voltage, the second voltage terminal of the third operational amplifier is grounded, and the output terminal of the third operational amplifier outputs a comparison voltage signal.

[0017] Optionally, the first control circuit further includes a seventh resistor, an eighth resistor, a ninth resistor, a first transistor, a second capacitor and a first diode;

[0018] The first end of the seventh resistor is electrically connected to the output end of the third operational amplifier, the second end of the seventh resistor is electrically connected to the first end of the first triode, the second end of the first triode is connected to the third voltage, and the third end of the first triode is connected to the third voltage through the eighth resistor;

[0019] The first end of the first diode is electrically connected to the third end of the first transistor, the second end of the first diode is electrically connected to the first end of the second capacitor, the second end of the second capacitor is electrically connected to the second end of the first transistor, and the ninth resistor is connected in parallel with the first diode;

[0020] The second end of the first diode is electrically connected to the first pole of the first power device, the second pole of the first power device is electrically connected to the input end of the power-consuming device, and the third pole of the first power device is electrically connected to the output end of the power supply device.

[0021] Optionally, the first power regulation circuit includes a fourth operational amplifier and a first control chip, and the first control chip includes a first input trigger terminal, a pulse output terminal, a power supply terminal and a ground terminal;

[0022] The first input trigger terminal of the first control chip is electrically connected to the positive terminal of the third operational amplifier, the pulse output terminal of the first control chip is electrically connected to the negative terminal of the fourth operational amplifier, the positive terminal of the fourth operational amplifier is connected to the second voltage, the first voltage terminal of the fourth operational amplifier is connected to the first voltage, the second voltage terminal of the fourth operational amplifier is grounded, and the output terminal of the fourth operational amplifier is electrically connected to the first input trigger terminal of the first control chip;

[0023] A power terminal of the first control chip is connected to the first voltage, and a ground terminal of the first control chip is grounded.

[0024] Optionally, the first power regulating circuit further includes a tenth resistor and a third capacitor, and the first control chip further includes a second input trigger terminal, a first regulating terminal, and a second regulating terminal;

[0025] The first end of the tenth resistor is connected to the first voltage, the second end of the tenth resistor is electrically connected to the first end of the third capacitor, the second end of the third capacitor is electrically connected to the second adjustment end of the first control chip, and the first adjustment end of the first control chip is electrically connected to the second end of the tenth resistor;

[0026] The second adjustment terminal of the first control chip is electrically connected to the second input trigger terminal of the first control chip.

[0027] Optionally, it also includes a second power detection circuit, a second power regulation circuit, a second control circuit and a second power device, the third pole of the second power device is electrically connected to the second pole of the first power device, the second pole of the second power device is electrically connected to the input end of the electrical equipment, and the first pole of the second power device is electrically connected to the output end of the second control circuit.

[0028] Optionally, the first-level protection circuit of the power protection circuit includes the first power detection circuit, the first power regulation circuit, the first control circuit and the first power device;

[0029] The secondary protection circuit of the power protection circuit includes the second power detection circuit, the second power regulation circuit, the second control circuit and the second power device.

[0030] Optionally, the power protection circuit further includes a first power indicator light circuit, wherein the first power indicator light circuit includes an eleventh resistor and a first indicator light;

[0031] The first end of the eleventh resistor is electrically connected to the output end of the power supply device, and the second end of the eleventh resistor is grounded through the first indicator light;

[0032] Also included is a second power indicator light circuit, the second power indicator light circuit including a twelfth resistor and a second indicator light;

[0033] The first end of the twelfth resistor is electrically connected to the input end of the electrical device, and the second end of the twelfth resistor is grounded through a second indicator light.

[0034] When the embodiment of the present invention detects that the power of the electric device exceeds the standard or is short-circuited through the first power detection circuit, a shutdown signal of the first power device is generated according to the overvoltage or overcurrent signal, and the first control circuit controls the first power device to shut down according to the shutdown signal to cut off the electrical connection between the electric device and the power supply device; when the electric device self-recovers, the first power regulation circuit generates an opening signal of the first power device, and the first control circuit turns on the first power device according to the opening signal, so that the electric device is quickly connected to the power supply system to ensure the normal operation of the system. By connecting the power protection circuit between the power supply device and the electric device, the embodiment of the present invention can effectively protect the power supply device and monitor the power safety of the electric device, and can quickly cut off the connection between the electric device and the power supply device when a short circuit or excessive power occurs in the electric device, and when the electric device self-recovers, the electric device can be connected to the power supply system in a timely and rapid manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of the structure of a power protection circuit provided by an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of the structure of another power protection circuit provided by an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of the structure of another power protection circuit provided by an embodiment of the present invention;

[0038] Figure 4A schematic diagram of the structure of another power protection circuit provided by an embodiment of the present invention;

[0039] Figure 5 A schematic diagram of the structure of another power protection circuit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0041] Figure 1 A schematic diagram of a power protection circuit provided by an embodiment of the present invention. Figure 1 , the power protection circuit includes: a first power detection circuit 10, a first power regulation circuit 20, a first control circuit 30 and a first power device Q1;

[0042] The first power device Q1 is connected between the power supply device 100 and the power consumption device 200, and the power supply device 100 outputs a power supply voltage to the power consumption device 200;

[0043] The first power detection circuit 10 includes a power input terminal A1 and a signal output terminal A2. The power input terminal A1 of the first power detection circuit 10 is connected to the first voltage VCC1. The first power detection circuit 10 is used to generate a shutdown signal of the first power device Q1 and output it from its signal output terminal A2 when the power-consuming device 200 is over-voltage or over-current.

[0044] The first power regulating circuit 20 includes a power input terminal B1 and a signal output terminal B2. The power input terminal B1 of the first power regulating circuit 20 is connected to the first voltage VCC1. The first power regulating circuit 20 is used to generate a turn-on signal of the first power device Q1 within a preset time according to a turn-off signal of the first power device Q1 and output it from its signal output terminal B2.

[0045] The first control circuit 30 includes an input terminal C1 and an output terminal C2. The input terminal C1 of the first control circuit 30 is electrically connected to the signal output terminal A2 of the first power detection circuit 10 and the signal output terminal B2 of the first power regulation circuit 20 respectively. The output terminal C2 of the first control circuit 30 is electrically connected to the first power device Q1.

[0046] Specifically, the first power device Q1 is electrically connected between the power supply device 100 and the power-consuming device 200. The first power detection circuit 10 detects whether the power of the power-consuming device 200 exceeds the standard or whether the power-consuming device is short-circuited. When the power of the power-consuming device 200 exceeds the standard, that is, the power-consuming device 200 has an overvoltage or overcurrent phenomenon, the power-consuming device 200 has no output at this time. When the first power detection circuit 10 detects an overvoltage or overcurrent signal of the power-consuming device 200, a shutdown signal of the first power device Q1 is generated according to the overvoltage or overcurrent signal. The first control circuit 30 controls the first power device Q1 to shut down according to the shutdown signal of the first power device Q1 received, and there is no power transmission between the power-consuming device 200 and the power supply device 100, thereby effectively protecting the power safety of the power-consuming device 200 and the power supply safety of the power supply device 100. The first power regulating circuit 20 generates a first power device Q1 turn-on signal within a preset time according to the first power device Q1 turn-off signal, turns on the first power device Q1, connects the power-consuming device 200 to the power supply system, and the system operates normally. When the power supply device 100 has an operating failure, the first power detection circuit 10 will also generate a first power device Q1 turn-off signal, disconnects the power supply device 100 from the power-consuming device 200, and can effectively monitor the operating conditions of the power supply device 100 and the power-consuming device 200.

[0047] When the power-consuming device or power supply device resumes normal operation, the first power regulating circuit 20 detects that the system power is below the limit power, and generates an opening signal for the first power device Q1, and controls the opening of the first power device through the first control circuit 30 to enable the system to operate normally.

[0048] Exemplarily, the power protection circuit can be applied to a power supply system with an input voltage of 10-60V, and the maximum current is set to 10A, that is, the maximum power is 600W, and the first power regulation circuit 20 adjusts the limit power to 600W. When the first power detection circuit 10 detects that the power of the device exceeds 600W, it outputs a shutdown signal of the first power device Q1 to the first control circuit 30, and the first control circuit 30 controls the first power device Q1 to be turned off, wherein the first power device Q1 can be an IGBT. The first power regulation circuit 20 outputs an on signal of the first power device Q1 within a preset time. If the power of the device still exceeds the standard within the preset time, the first power regulation circuit 20 continues to convert the shutdown signal of the first power device Q1 into an on signal of the first power device Q1 until the power of the device is lower than 600W. The first power regulation circuit 20 continues to output the on signal of the first power device Q1, and controls the first power device Q1 to be turned on through the first control circuit 30, so that the power-consuming device 200 is connected to the power supply system.

[0049] When the embodiment of the present invention detects that the power of the electric device exceeds the standard or is short-circuited through the first power detection circuit, a shutdown signal of the first power device is generated according to the overvoltage or overcurrent signal, and the first control circuit controls the first power device to shut down according to the shutdown signal to cut off the electrical connection between the electric device and the power supply device; when the electric device self-recovers, the first power regulation circuit generates an opening signal of the first power device, and the first control circuit turns on the first power device according to the opening signal, so that the electric device is quickly connected to the power supply system to ensure the normal operation of the system. By connecting the power protection circuit between the power supply device and the electric device, the embodiment of the present invention can effectively protect the power supply device and monitor the power safety of the electric device, and can quickly cut off the connection between the electric device and the power supply device when a short circuit or excessive power occurs in the electric device, and when the electric device self-recovers, the electric device can be connected to the power supply system in a timely and rapid manner.

[0050] Optional, Figure 2 FIG. 1 is a schematic diagram of another power supply protection circuit provided by an embodiment of the present invention. Figure 2 , the first power detection circuit 10 includes a current detection circuit 11, and the current detection circuit 11 includes a first resistor R1, a second resistor R2, a third resistor R3 and a first operational amplifier OA1;

[0051] The first end of the first resistor R1 is connected to the first voltage VCC1, the second end of the first resistor R1 is electrically connected to the positive terminal of the first operational amplifier OA1 through the second resistor R2, the negative terminal of the first operational amplifier OA1 is grounded through the third resistor R3, the first voltage terminal of the first operational amplifier OA1 is connected to the first voltage VCC1, the second voltage terminal of the first operational amplifier OA1 is grounded, and the output terminal of the first operational amplifier OA1 is electrically connected to the input terminal C1 of the first control circuit 30.

[0052] Specifically, first determine the output voltage of the power supply system, and then determine the limiting current. The limiting current is determined by the third resistor R3, wherein the third resistor R3 is an adjustable resistor, and the limiting power can be obtained according to the product of the limiting current and the voltage. The first operational amplifier OA1 is used for comparison function, the positive terminal of the first operational amplifier OA1 inputs the current reference value, and the negative terminal of the first operational amplifier OA1 inputs the detected current value. When the current value of the positive terminal of the first operational amplifier OA1 is greater than the current value of the negative terminal of the first operational amplifier OA1, a high level is output; when the current value of the positive terminal of the first operational amplifier OA1 is less than the current value of the negative terminal of the first operational amplifier OA1, a low level is output. When the first power detection circuit 10 detects that the power of the electrical equipment 200 exceeds the standard, the current detected at the negative terminal of the first operational amplifier OA1 is greater than the reference current of its positive terminal, and the first operational amplifier OA1 outputs a low level; when the electrical equipment recovers after self-recovery, its current value is less than the reference current, and the first operational amplifier OA1 outputs a high level.

[0053] Optionally, based on the above embodiment, continue to refer to Figure 2 , the first power detection circuit 10 further includes a voltage detection circuit 12, the voltage detection circuit 12 includes a fourth resistor R4, a fifth resistor R5, a first capacitor C1 and a second operational amplifier OA1;

[0054] The positive terminal of the second operational amplifier OA1 is connected to the second voltage VCC2, the negative terminal of the second operational amplifier OA2 is electrically connected to the second end of the fourth resistor R4, the first end of the fourth resistor R4 is connected to the third voltage VCC3, the second end of the fourth resistor R4 is grounded through the fifth resistor R5, and the first capacitor C1 is connected in parallel to both ends of the fifth resistor R5;

[0055] A first voltage terminal of the second operational amplifier OA1 is connected to the first voltage VCC1 , a second terminal of the second operational amplifier OA1 is grounded, and an output terminal of the second operational amplifier OA2 is electrically connected to an input terminal C1 of the first control circuit 30 .

[0056] Specifically, the first voltage VCC1 is the power supply voltage of the second operational amplifier OA2, the second voltage VCC2 is the reference voltage, and the third voltage VCC3 is the input voltage of the first power device Q1, which is also the input voltage of the electric device 200. When the power of the electric device 200 exceeds the standard, that is, when the electric device 200 is over-voltage, the voltage output to the negative terminal of the second operational amplifier OA2 by the third voltage VCC3 after passing through the fourth resistor R4 and the fifth resistor R5 is greater than the reference voltage VCC2, so the second operational amplifier OA2 outputs a low level. When the input voltage VCC3 of the electric device 200 is within the normal voltage range, the voltage output through the fourth resistor R4 and the fifth resistor R5 is less than the reference voltage, and the second operational amplifier OA2 outputs a high level. The first control circuit 30 controls the first power device Q1 to turn off according to the low level output by the first operational amplifier OA1 and the second operational amplifier OA2, and disconnects the electric device 200 from the power supply device 100, thereby ensuring the power safety of the electric device and the power supply safety of the power supply device.

[0057] Optional, Figure 3 FIG. 1 is a schematic diagram of another power supply protection circuit provided by an embodiment of the present invention. Figure 3 , the first control circuit 30 includes a sixth resistor R6 and a third operational amplifier OA3;

[0058] The first end of the sixth resistor R6 is electrically connected to the positive terminal of the third operational amplifier OA3, the second end of the sixth resistor R6 is connected to the first voltage VCC1, the positive terminal of the third operational amplifier OA3 is electrically connected to the output terminal of the first operational amplifier OA1 and the output terminal of the second operational amplifier OA2 respectively, the negative terminal of the third operational amplifier OA3 is connected to the second voltage VCC2, the first voltage terminal of the third operational amplifier OA3 is connected to the first voltage VCC1, the second voltage terminal of the third operational amplifier OA3 is grounded, and the output terminal of the third operational amplifier OA3 outputs a comparison voltage signal.

[0059] Specifically, the second voltage VCC2 is the reference voltage of the third operational amplifier OA3, and the positive terminal of the third operational amplifier OA3 receives the shutdown signal of the first power device Q1 output by the first operational amplifier OA1 and the second operational amplifier OA2 respectively. When the third operational amplifier OA3 receives the low level output by the first operational amplifier OA1 or the second operational amplifier OA2, the first power device Q1 is controlled to be turned off, and the power-consuming device 200 is disconnected from the power supply device 100; when the third operational amplifier OA3 receives the high level output by the first operational amplifier OA1 or the second operational amplifier OA2, the first power device Q1 is controlled to be turned on, and the power-consuming device 200 is reconnected to the power supply system of the power supply device 100.

[0060] Optionally, based on the above embodiment, continue to refer to Figure 3 , the first control circuit 30 also includes a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a first transistor Q2, a second capacitor C2 and a first diode D1;

[0061] A first end of the seventh resistor R7 is electrically connected to the output end of the third operational amplifier OA3, a second end of the seventh resistor R7 is electrically connected to the first end of the first triode Q2, a second end of the first triode Q2 is connected to the third voltage VCC3, and a third end of the first triode Q2 is connected to the third voltage VCC3 through an eighth resistor R8;

[0062] The first end of the first diode D1 is electrically connected to the third end of the first transistor Q2, the second end of the first diode D1 is electrically connected to the first end of the second capacitor C2, the second end of the second capacitor C2 is electrically connected to the second end of the first transistor Q2, and the ninth resistor R9 is connected in parallel with the first diode D1;

[0063] The second end of the first diode D1 is electrically connected to the first electrode of the first power device Q1 , the second electrode of the first power device Q1 is electrically connected to the input end of the power-consuming device 200 , and the third electrode of the first power device Q1 is electrically connected to the output end of the power supply device 100 .

[0064] Specifically, the first power device Q1 may be an IGBT, which has the characteristics of low driving power and low saturation voltage drop. When the third operational amplifier OA3 outputs a high level, that is, the turn-on signal of the first power device Q1, the first power device Q1 cannot be fully turned on due to the small driving capability of the high-level turn-on signal. Therefore, the current of the turn-on signal of the first power device Q1 of the third operational amplifier OA3 is amplified by the first transistor Q2 to enhance its driving capability. The first power device Q1 is connected between the power supply device 100 and the power-consuming device 200. When the third operational amplifier OA3 outputs a high level, the first power device Q1 is controlled to be turned on after the first transistor Q2 amplifies the driving capability of the turn-on signal, and the power-consuming device 200 is electrically connected to the power supply device 100. Since the switching speed of the first power device is very fast, the power-consuming device 200 can be quickly connected to the power supply system to ensure the normal operation of the system.

[0065] Optional, Figure 4 FIG. 1 is a schematic diagram of another power supply protection circuit provided by an embodiment of the present invention. Figure 4 , the first power regulation circuit 20 includes a fourth operational amplifier OA4 and a first control chip U1, the first control chip U1 includes a first input trigger terminal 1, a pulse output terminal 2, a power supply terminal 3 and a ground terminal 4;

[0066] The first input trigger terminal 1 of the first control chip U1 is electrically connected to the positive terminal of the third operational amplifier OA3, the pulse output terminal 2 of the first control chip U1 is electrically connected to the negative terminal of the fourth operational amplifier OA4, the positive terminal of the fourth operational amplifier OA4 is connected to the second voltage VCC2, the first voltage terminal of the fourth operational amplifier OA4 is connected to the first voltage VCC1, the second voltage terminal of the fourth operational amplifier OA4 is grounded, and the output terminal of the fourth operational amplifier OA4 is electrically connected to the first input trigger terminal 1 of the first control chip U1;

[0067] A power terminal 3 of the first control chip U1 is connected to a first voltage VCC1 , and a ground terminal 4 of the first control chip U1 is grounded.

[0068] Specifically, the first control chip U1 can be a multivibrator HCF4538BEY, which is used to control the flipping of high and low levels to complete the conduction of the first power device Q1. During the normal operation of the system, the first input trigger terminal 1 of the first control chip U1 is at a high level. When the first power detection circuit 10 detects that the power of the electrical equipment 200 exceeds the standard, the first power detection circuit 10 outputs a low-level shutdown signal of the first power device Q1. At this time, the level of the first input trigger terminal 1 of the first control chip U1 changes from a high level to a low level. The pulse output terminal 2 of the first control chip U1 simultaneously outputs a low level to the negative terminal of the fourth operational amplifier OA4. The positive terminal of the fourth operational amplifier OA4 inputs a reference voltage. Since the low level of the negative terminal of the fourth operational amplifier OA4 is less than the reference voltage input to its positive terminal, the fourth operational amplifier OA4 outputs a low level, and the first power device Q1 is in a shutdown state. When the electrical equipment 200 recovers, the first power detection circuit 10 outputs a high level. Since the signal received by the first input trigger terminal 1 of the first control chip U1 is a high level, its pulse output terminal 2 outputs a high level to the negative terminal of the fourth operational amplifier OA4. The fourth operational amplifier OA4 outputs a high level. The third operational amplifier OA3 controls the first power device Q1 to turn on according to the high level signal, and quickly connects the electrical equipment 200 to the power supply system.

[0069] Optionally, based on the above embodiment, continue to refer to Figure 4 , the first power regulating circuit 20 further includes a tenth resistor R10 and a third capacitor C3, and the first control chip U1 further includes a second input trigger terminal 5, a first regulating terminal 6 and a second regulating terminal 7;

[0070] The first end of the tenth resistor R10 is connected to the first voltage VCC1, the second end of the tenth resistor R10 is electrically connected to the first end of the third capacitor C3, the second end of the third capacitor C3 is electrically connected to the second adjustment end 7 of the first control chip U1, and the first adjustment end 6 of the first control chip U1 is electrically connected to the second end of the tenth resistor R10;

[0071] The second regulating terminal 7 of the first control chip U1 is electrically connected to the second input trigger terminal 5 of the first control chip U1 .

[0072] Specifically, the tenth resistor R10 and the third capacitor C3 together form an RC regulating circuit for adjusting the switching time of the high and low levels. Exemplarily, if the time parameter is calculated as 3s through the values ​​of the tenth resistor R10 and the third capacitor C3, the level flipping time interval of the first control chip U1 is 3s. When the level of the first input trigger terminal 1 of the first control chip U1 changes from a high level to a low level, the pulse output terminal 2 of the first control chip U1 simultaneously outputs a low level. After 3s, the first control chip U1 performs a level flip, flips the low level output of the pulse output terminal 2 to a high level and outputs it to the negative terminal of the fourth operational amplifier OA4, and the fourth operational amplifier OA4 outputs a high level. If the electric device completes self-recovery within 3s, the pulse output terminal 2 of the first control chip U1 always outputs a high level, and the system operates normally. The first control circuit controls the first power device Q1 to turn on after amplifying the current driving capability of the first transistor Q2 based on the high level turn-on signal of the first power device Q1 output by the fourth operational amplifier OA4, and connects the electric device 200 with the power supply device 100; if the electric device 200 does not complete self-recovery within 3s, the first power detection circuit 10 still outputs a low level turn-off signal of the first power device Q1, and the first input trigger terminal 1 of the first control chip U1 changes from a high level to a low level again. After a time interval of 3s, the low level output by the pulse output terminal 2 of the first control chip U1 is flipped to a high level until the first power detection circuit 10 outputs a high level, so as to complete the smooth connection of the electric device 200 to the power supply system and ensure the power safety of the electric device 200.

[0073] Optional, Figure 5 FIG. 1 is a schematic diagram of another power supply protection circuit provided by an embodiment of the present invention. Figure 5 The power protection circuit also includes a second power detection circuit 40, a second power regulation circuit 50, a second control circuit 60 and a second power device Q3, the third pole of the second power device Q3 is electrically connected to the second pole of the first power device Q1, the second pole of the second power device Q3 is electrically connected to the input end of the electrical equipment 200, and the first pole of the second power device Q3 is electrically connected to the output end F2 of the second control circuit 60.

[0074] Specifically, the first power detection circuit 10, the first power regulation circuit 20, the first control circuit 30 and the first power device Q1 together constitute the primary protection circuit of the power protection circuit, and the second power detection circuit 40, the second power regulation circuit 50, the second control circuit 60 and the second power device Q3 together constitute the secondary protection circuit of the power protection circuit. The secondary protection circuit is used to form a double protection for the power protection circuit to improve the safety and reliability of the power protection circuit. Among them, the secondary protection circuit has the same circuit structure and devices as the primary protection circuit, and has the same working principle and beneficial effects as the primary protection circuit, which will not be repeated here.

[0075] Optionally, based on the above embodiment, continue to refer to Figure 5 The power protection circuit provided in the embodiment of the present invention further includes a first power indicator light circuit 70, and the first power indicator light circuit 70 includes an eleventh resistor R11 and a first indicator light LED1;

[0076] A first end of the eleventh resistor R11 is electrically connected to the output end of the power supply device 100, and a second end of the eleventh resistor R11 is grounded through the first indicator LED1;

[0077] It also includes a second power indicator light circuit 80, which includes a twelfth resistor R12 and a second indicator light LED2;

[0078] A first end of the twelfth resistor R12 is electrically connected to the input end of the electric device 200 , and a second end of the twelfth resistor R12 is grounded through the second indicator LED2 .

[0079] Specifically, when the power supply device 100 operates normally, the first indicator light LED1 is lit to indicate that the power supply device 100 is in a working state; when the power-consuming device 200 operates normally, the first power device Q1 and the second power device Q2 are both turned on, and the second indicator light LED2 is lit to indicate that the power-consuming device 200 is in a safe power consumption state.

[0080] The specific working principle of the power protection circuit provided by the embodiment of the present invention is as follows:

[0081] The power protection circuit provided in the embodiment of the present invention can be applied to a power supply system with a voltage of 10-60V, and connected between the power supply device 100 and the power consumption device 200. The first power detection circuit 10 detects whether the power of the power consumption device 200 exceeds the standard. When the current detection circuit 11 detects an overcurrent signal or the voltage detection circuit 12 detects an overvoltage signal, the first power detection circuit outputs a low-level shutdown signal of the first power device Q1, and the first control circuit 30 controls the first power device Q1 to shut down according to the shutdown signal of the first power device Q1, so that the power supply device 100 is disconnected from the power consumption device 200. At the same time, the first power regulation circuit 20 outputs a low level at the pulse output terminal 2 of the first control chip U1 according to the shutdown signal of the first power device Q1. Since this low level is less than the reference voltage value, after comparison by the fourth operational amplifier OA4, the fourth operational amplifier OA4 outputs a low level. The level flipping time of the first control chip U1 is set by the tenth resistor R10 and the third capacitor C3. After each level flipping time, the first control chip U1 will flip the low level output by its pulse output terminal 2 to a high level until the first input trigger terminal 1 receives the turn-on signal of the first power device Q1 outputted at a high level by the first power detection circuit 10. After the electric device 200 recovers, the current and voltage detected by the first operational amplifier OA1 and the second operational amplifier OA2 are lower than the reference value, so the first operational amplifier OA1 and the second operational amplifier OA2 output a high level. The first control circuit 30 outputs a high level driving signal for controlling the first power device Q1 to turn on after comparing the high level outputted by the first operational amplifier OA1 and the second operational amplifier OA2 with the reference voltage through the third operational amplifier OA3, and amplifies the current driving capability of the driving signal through the first transistor Q2 to ensure that the first power device Q1 can be fully turned on. Since the first power device Q1 is an IGBT semiconductor device with a faster switching speed, it can ensure that the electric device 200 is quickly connected to the power supply system. The second power detection circuit 40 detects the voltage output by the first power device Q1 to provide secondary protection for the electrical device 200 to prevent overvoltage and overcurrent.

[0082] When the embodiment of the present invention detects that the power of the electric device exceeds the standard or is short-circuited through the first power detection circuit, a shutdown signal of the first power device is generated according to the overvoltage or overcurrent signal, and the first control circuit controls the first power device to be shut down according to the shutdown signal to cut off the electrical connection between the electric device and the power supply device; when the electric device self-recovers, the first power regulation circuit generates an opening signal of the first power device, and the first control circuit turns on the first power device according to the opening signal, and the electric device is quickly connected to the power supply system to ensure the normal operation of the system. At the same time, a secondary protection circuit can also be set to prevent the primary protection circuit from being unable to completely remove the fault when the power of the electric device exceeds the standard. The embodiment of the present invention can effectively protect the power supply device and monitor the power safety of the electric device by connecting the power protection circuit between the power supply device and the electric device, and can quickly cut off the connection between the electric device and the power supply device when the electric device is short-circuited or the power exceeds the standard. When the electric device self-recovers, the electric device can be connected to the power supply system in a timely and rapid manner.

[0083] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A power protection circuit, characterized in that: include: A first power detection circuit, a first power regulation circuit, a first control circuit and a first power device; The first power device is connected between a power supply device and a power-consuming device, and the power supply device outputs a power supply voltage to the power-consuming device; The first power detection circuit comprises a power input terminal and a signal output terminal, the power input terminal of the first power detection circuit is connected to a first voltage, and the first power detection circuit is used to generate a shutdown signal of the first power device and output it from its signal output terminal when the electrical device is over-voltage or over-current; The first power regulating circuit comprises a power input terminal and a signal output terminal, the power input terminal of the first power regulating circuit is connected to the first voltage, and the first power regulating circuit is used to generate a turn-on signal of the first power device within a preset time according to a turn-off signal of the first power device and output it from its signal output terminal; The first control circuit comprises an input end and an output end, the input end of the first control circuit is electrically connected to the signal output end of the first power detection circuit and the signal output end of the first power regulation circuit respectively, and the output end of the first control circuit is electrically connected to the first power device; The first control circuit includes a third operational amplifier; The first power regulation circuit includes a fourth operational amplifier and a first control chip, wherein the first control chip includes a first input trigger terminal, a pulse output terminal, a power supply terminal and a ground terminal; The first input trigger terminal of the first control chip is electrically connected to the positive terminal of the third operational amplifier, the pulse output terminal of the first control chip is electrically connected to the negative terminal of the fourth operational amplifier, the positive terminal of the fourth operational amplifier is connected to the second voltage, the first voltage terminal of the fourth operational amplifier is connected to the first voltage, the second voltage terminal of the fourth operational amplifier is grounded, and the output terminal of the fourth operational amplifier is electrically connected to the first input trigger terminal of the first control chip; The power supply terminal of the first control chip is connected to the first voltage, and the ground terminal of the first control chip is grounded; The first power regulating circuit further includes a tenth resistor and a third capacitor, and the first control chip further includes a second input trigger terminal, a first regulating terminal and a second regulating terminal; The first end of the tenth resistor is connected to the first voltage, the second end of the tenth resistor is electrically connected to the first end of the third capacitor, the second end of the third capacitor is electrically connected to the second adjustment end of the first control chip, and the first adjustment end of the first control chip is electrically connected to the second end of the tenth resistor; The second adjustment terminal of the first control chip is electrically connected to the second input trigger terminal of the first control chip; It also includes a second power detection circuit, a second power regulation circuit, a second control circuit and a second power device, the third pole of the second power device is electrically connected to the second pole of the first power device, the second pole of the second power device is electrically connected to the input end of the electrical equipment, and the first pole of the second power device is electrically connected to the output end of the second control circuit.

2. The power protection circuit according to claim 1, characterized in that: The first power detection circuit includes a current detection circuit, and the current detection circuit includes a first resistor, a second resistor, a third resistor and a first operational amplifier; The first end of the first resistor is connected to the first voltage, the second end of the first resistor is electrically connected to the positive terminal of the first operational amplifier through the second resistor, the negative terminal of the first operational amplifier is grounded through the third resistor, the first voltage terminal of the first operational amplifier is connected to the first voltage, the second voltage terminal of the first operational amplifier is grounded, and the output terminal of the first operational amplifier is electrically connected to the input terminal of the first control circuit.

3. The power protection circuit according to claim 2, characterized in that: The first power detection circuit further includes a voltage detection circuit, and the voltage detection circuit includes a fourth resistor, a fifth resistor, a first capacitor, and a second operational amplifier; The positive terminal of the second operational amplifier is connected to the second voltage, the negative terminal of the second operational amplifier is electrically connected to the second end of the fourth resistor, the first end of the fourth resistor is connected to the third voltage, the second end of the fourth resistor is grounded through the fifth resistor, and the first capacitor is connected in parallel to both ends of the fifth resistor; A first voltage terminal of the second operational amplifier is connected to the first voltage, a second terminal of the second operational amplifier is grounded, and an output terminal of the second operational amplifier is electrically connected to an input terminal of the first control circuit.

4. The power protection circuit according to claim 3, characterized in that: The first control circuit includes a sixth resistor; The first end of the sixth resistor is electrically connected to the positive terminal of the third operational amplifier, the second end of the sixth resistor is connected to the first voltage, the positive terminal of the third operational amplifier is electrically connected to the output terminal of the first operational amplifier and the output terminal of the second operational amplifier respectively, the negative terminal of the third operational amplifier is connected to the second voltage, the first voltage terminal of the third operational amplifier is connected to the first voltage, the second voltage terminal of the third operational amplifier is grounded, and the output terminal of the third operational amplifier outputs a comparison voltage signal.

5. The power protection circuit according to claim 4, characterized in that: The first control circuit also includes a seventh resistor, an eighth resistor, a ninth resistor, a first triode, a second capacitor and a first diode; The first end of the seventh resistor is electrically connected to the output end of the third operational amplifier, the second end of the seventh resistor is electrically connected to the first end of the first triode, the second end of the first triode is connected to the third voltage, and the third end of the first triode is connected to the third voltage through the eighth resistor; The first end of the first diode is electrically connected to the third end of the first transistor, the second end of the first diode is electrically connected to the first end of the second capacitor, the second end of the second capacitor is electrically connected to the second end of the first transistor, and the ninth resistor is connected in parallel with the first diode; The second end of the first diode is electrically connected to the first pole of the first power device, the second pole of the first power device is electrically connected to the input end of the power-consuming device, and the third pole of the first power device is electrically connected to the output end of the power supply device.

6. The power protection circuit according to claim 1, characterized in that: The primary protection circuit of the power protection circuit includes the first power detection circuit, the first power regulation circuit, the first control circuit and the first power device; The secondary protection circuit of the power protection circuit includes the second power detection circuit, the second power regulation circuit, the second control circuit and the second power device.

7. The power protection circuit according to claim 6, characterized in that: Also included is a first power indicator light circuit, the first power indicator light circuit comprising an eleventh resistor and a first indicator light; The first end of the eleventh resistor is electrically connected to the output end of the power supply device, and the second end of the eleventh resistor is grounded through the first indicator light; Also included is a second power indicator light circuit, the second power indicator light circuit including a twelfth resistor and a second indicator light; The first end of the twelfth resistor is electrically connected to the input end of the electrical device, and the second end of the twelfth resistor is grounded through a second indicator light.

Images