A current detection system based on inductor elements

Abstract

The present invention discloses a current detection system based on an inductor element, which relates to the technical field of current detection, and includes a power switch module for adjusting the conduction angle of a power switch device; a drive control module for improving the signal driving capability and pulling down the driving potential; a current sampling module for detecting the rate of change of the inductor current; an output detection module for adjusting the first fault threshold and the second fault threshold according to the degree of aging and performing a type I short circuit or a type II short circuit detection; a conduction detection module for detecting a saturated conduction voltage drop; an aging judgment module for aging degree detection; a detection adjustment module for adjusting the third fault threshold according to the degree of aging and cooperating with the short circuit judgment module to perform a type II short circuit detection; and an intelligent control module for signal reception and module control. The current detection system based on the inductor element of the present invention improves the sensitivity of fault current detection, accurately determines whether the power switch module is normal, and improves system safety.

Description

Technical Field

[0001] The invention relates to the technical field of current detection, and in particular to a current detection system based on an inductor element. Background Art

[0002] Insulated Gate Bipolar Transistor (IGBT) is a semiconductor device widely used in the field of power electronics. It has the characteristics of high input impedance, low on-state voltage drop, fast switching speed, etc. IGBT detection is accompanied by the application and development of IGBT. When performing switch control, it is necessary to quickly and reliably detect the current in order to determine whether the IGBT is abnormal and shut down the IGBT when it is abnormal to prevent more serious faults. The IGBT in the prior art generally determines whether the IGBT is abnormal by the current change rate of the parasitic inductance, and performs a first or second type of short-circuit protection when an abnormality occurs. However, due to long-term use, the IGBT is prone to different degrees of aging, which leads to the performance degradation of the IGBT, increased voltage drop, slower switching speed, etc. When the set abnormal limit value cannot be automatically adjusted, it leads to the inability to make an abnormal judgment in time, and it is impossible to determine whether the IGBT detection is normal, resulting in the inability to effectively protect in time, reducing the safety of the IGBT, so it needs to be improved. Summary of the invention

[0003] The embodiment of the present invention provides a current detection system based on an inductor element to solve the problems raised in the above background technology.

[0004] According to an embodiment of the present invention, a current detection system based on an inductor element is provided, comprising: a power switch module, a drive control module, a current sampling module, an output detection module, a conduction detection module, an aging judgment module, a short circuit judgment module, a detection and adjustment module and an intelligent control module;

[0005] A power switch module, connected to the drive control module, is used to receive the drive signal output by the drive control module and adjust the conduction angle of the power switch device, and the power switch device controls the transmission of the connected electric energy and supplies power to the load;

[0006] A drive control module, connected to the intelligent control module, the output detection module and the short-circuit judgment module, for amplifying the pulse signal output by the intelligent control module and outputting a drive signal, and stopping outputting the drive signal and lowering the drive potential of the power switch module when receiving the first abnormal signal or the second abnormal signal output by the output detection module or the third abnormal signal output by the short-circuit judgment module;

[0007] A current sampling module, connected to the power switch module, for detecting a current change rate of the inductance of the power switch module and outputting a first detection signal;

[0008] an output detection module, connected to the current sampling module and the aging judgment module, and used to set a first fault threshold and a second fault threshold, wherein the voltage of the first fault threshold is greater than the second fault threshold, and when the first detection signal is less than the second fault signal, a first abnormal signal is output, and when the first detection signal is only less than the first fault signal, a second abnormal signal is output, and when the first aging signal, the second aging signal or the third aging signal output by the aging judgment module is received, the voltage values ​​of the first fault threshold and the second fault threshold are increased;

[0009] A conduction detection module, connected to the power switch module, for detecting a saturation conduction voltage drop of the power switch module and outputting a second detection signal;

[0010] an aging judgment module, connected to the conduction detection module and the short-circuit judgment module, and used to set a first aging threshold, a second aging threshold, and a third aging threshold; when the second detection signal is greater than the first aging threshold, the first aging signal is output; when the second detection signal is greater than the second aging threshold, the second aging signal is output and the first aging signal is stopped from being output; when the second detection signal is greater than the third aging threshold, the third aging signal is output and the first aging signal and the second aging signal are stopped from being output; and when the third abnormal signal output by the short-circuit judgment module is received, the aging degree judgment is stopped;

[0011] A detection and adjustment module, connected to the aging judgment module, used to set a third fault threshold value, and reduce the voltage value of the third fault threshold value upon receiving the first aging signal, the second aging signal or the third aging signal;

[0012] A short circuit judgment module, connected to the detection and adjustment module and the conduction detection module, and configured to output a third abnormal signal when the second detection signal is greater than the third fault detection signal;

[0013] The intelligent control module is connected to the aging judgment module, the short-circuit judgment module and the output detection module, and is used to output a pulse signal, receive a first aging signal, a second aging signal or a third aging signal, stop outputting the pulse signal when receiving a first abnormal signal, a second abnormal signal or a third abnormal signal, and perform abnormal detection and display when the second abnormal signal and the third abnormal signal are not received at the same time.

[0014] As a further solution of the present invention: the power switch module includes a power interface, a first capacitor, a first load and a power switch device;

[0015] Preferably, the first end of the power interface is connected to one end of the first capacitor and is connected to the collector of the power switching device through the first load, the gate of the power switching device is connected to the drive control module, the power emitter of the power switching device is connected to the current sampling module, and the auxiliary emitter of the power switching device is connected to the other end of the first capacitor and the second end of the power interface.

[0016] As a further solution of the present invention: the current sampling module includes a first detection inductor, a fifth resistor, a second power supply, a sixth diode, a sixth resistor and a seventh diode;

[0017] Preferably, one end of the first detection inductor is connected to the power emitter of the power switching device, the other end of the first detection inductor is connected to the auxiliary emitter of the power switching device and the first end of the fifth resistor, the second end of the fifth resistor is connected to the output detection module, the cathode of the seventh diode and the anode of the sixth diode, and is connected to the second power supply and the cathode of the sixth diode through the sixth resistor, and the anode of the seventh diode is grounded.

[0018] As a further solution of the present invention: the conduction detection module includes a second capacitor, a first resistor, a second resistor, a third capacitor, a first diode, a second diode, a third diode, a fourth diode, a fifth diode, a fourth resistor, a third resistor, a first power supply and a first operational amplifier;

[0019] Preferably, one end of the second capacitor is connected to the cathode of the first diode and the collector of the power switching device and is connected to the other end of the second capacitor, one end of the second resistor, one end of the third capacitor, the anode of the second diode and the cathode of the fourth diode through the first resistor, the cathode of the second diode is connected to the cathode of the third diode, the anode of the third diode is connected to the cathode of the fifth diode, the other end of the third capacitor, the other end of the second resistor and the ground, the anode of the fourth diode is connected to the in-phase terminal of the first op amp and the anode of the first diode and is connected to the first power supply and one end of the fourth resistor through the third resistor, and the other end of the fourth resistor is connected to the anode of the fifth diode and the inverting terminal of the first op amp.

[0020] As a further solution of the present invention: the short circuit judgment module includes a first comparator; the intelligent control module includes a first controller, a fifth logic device and a first indicator light;

[0021] Preferably, the in-phase end of the first comparator is connected to the output end of the first operational amplifier, the inverting end of the first comparator is connected to the detection and adjustment module, the first comparator is connected to the aging judgment module and the first end of the seventh resistor, the second end of the seventh resistor is connected to the IO7 end of the first controller and the B end of the fifth logic device, the A end of the fifth logic device is connected to the IO5 end of the first controller, the Y end of the fifth logic device is connected to the IO8 end of the first controller and the anode of the first indicator light, and the cathode of the first indicator light is grounded.

[0022] As a further solution of the present invention: the aging judgment module includes an aging threshold device, a second comparator, a third comparator, a fourth comparator, a first inverter, a second inverter, a third inverter, a first logic device, a second logic device and a third logic device;

[0023] Preferably, the first end, the second end and the third end of the aging threshold device are respectively connected to the inverting end of the second comparator, the inverting end of the third comparator and the inverting end of the fourth comparator, the non-inverting end of the second comparator is connected to the non-inverting end of the third comparator, the non-inverting end of the fourth comparator and the output end of the first operational amplifier, the output end of the second comparator is connected to the A end of the first logic device, the output end of the third comparator is connected to the input end of the first inverter and the A end of the second logic device, the output end of the fourth comparator is connected to the input end of the second inverter and the A end of the third logic device, the B end of the first logic device, the B end of the second logic device and the B end of the third logic device are respectively connected to the output end of the first inverter, the output end of the second inverter and the output end of the third inverter, the input end of the third inverter is connected to the output end of the first comparator, and the Y end of the first logic device, the Y end of the second logic device and the Y end of the third logic device are respectively connected to the IO2 end, IO3 end and IO4 end of the first controller.

[0024] As a further solution of the present invention: the detection and adjustment module includes a third power supply, an eighth resistor, a ninth resistor, a first switch tube, a second switch tube, a third switch tube, a tenth resistor, an eleventh resistor and a twelfth resistor;

[0025] Preferably, the third power supply is connected to one end of the ninth resistor, the in-phase end of the first comparator, the collector of the first switch tube, the collector of the second switch tube and the collector of the third switch tube through the eighth resistor, the emitter of the first switch tube is connected to the other end of the ninth resistor, one end of the eleventh resistor, one end of the twelfth resistor and the ground through the tenth resistor, the other end of the eleventh resistor and the other end of the twelfth resistor are respectively connected to the emitter of the second switch tube and the emitter of the third switch tube, and the base of the first switch tube, the base of the second switch tube and the base of the third switch tube are respectively connected to the Y end of the first logic device, the Y end of the second logic device and the Y end of the third logic device.

[0026] As a further solution of the present invention: the output detection module includes a first-class reference source, a second-class reference source, a seventh switch tube, a fifth comparator, a sixth comparator, a fourth inverter and a fifth inverter;

[0027] Preferably, the first end of the first type of reference source is connected to the first end of the second type of reference source and the Y end of the first logic device, the second end of the first type of reference source is connected to the second end of the second type of reference source and the Y end of the second logic device, the third end of the first type of reference source is connected to the third end of the second type of reference source and the Y end of the third logic device, the fourth end of the first type of reference source is connected to the inverting end of the fifth comparator, the inverting end of the sixth comparator is connected to the fourth end of the second type of reference source, the output end of the fifth comparator and the output end of the sixth comparator are respectively connected to the input end of the fourth inverter and the input end of the fifth inverter, the output end of the fourth inverter is connected to the IO5 end of the first controller and the base of the seventh switch tube, the collector of the seventh switch tube is connected to the output end of the fifth inverter and the IO6 end of the first controller, the emitter of the seventh switch tube is grounded, and the non-inverting end of the fifth comparator is connected to the non-inverting end of the sixth comparator and the second end of the fifth resistor.

[0028] As a further solution of the present invention: a reference source includes a fourth power supply, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a fourth switch tube, a fifth switch tube and a sixth switch tube;

[0029] Preferably, the fourth power supply connects the collector of the fourth switch tube, the collector of the fifth switch tube and the collector of the sixth switch tube and connects the inverting end of the fifth comparator, one end of the seventeenth resistor, one end of the eighteenth resistor, one end of the nineteenth resistor and one end of the sixteenth resistor through the fifteenth resistor, the other end of the sixteenth resistor is grounded, the other end of the seventeenth resistor, the other end of the eighteenth resistor and the other end of the nineteenth resistor are respectively connected to the emitter of the fourth switch tube, the emitter of the fifth switch tube and the emitter of the sixth switch tube, the base of the fourth switch tube, the base of the fifth switch tube and the base of the sixth switch tube are respectively connected to the Y end of the first logic device, the Y end of the second logic device and the Y end of the third logic device.

[0030] As a further solution of the present invention: the drive control module includes a fourth logic device, a drive device, an eighth diode, a ninth diode and a tenth diode;

[0031] Preferably, the A end of the fourth logic device is connected to the IO1 end of the first controller, the B end of the fourth logic device is connected to the cathode of the eighth diode, the cathode of the ninth diode and the cathode of the tenth diode, and the anode of the eighth diode, the anode of the ninth diode and the anode of the tenth diode are respectively connected to the second end of the seventh resistor, the output end of the fourth inverter and the output end of the fifth inverter.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows: the current detection system based on the inductor element of the present invention is driven by the intelligent control module in cooperation with the drive control module to drive the power transmission state of the power switch module, the current sampling module detects the inductor current change rate of the power switch module, cooperates with the output detection module to set the first fault threshold and the second fault threshold, and performs a type I short circuit detection and a type II short circuit detection, and at the same time, the conduction detection module detects the saturated conduction voltage drop of the power switch module, cooperates with the detection adjustment module and the short circuit judgment module to perform a type II short circuit detection, cooperates with the aging detection module to perform three types of aging degree detection, and adjusts the detection parameters of the detection adjustment module and the output detection module according to different aging degrees, improves the sensitivity of fault current judgment, accurately judges whether the power switch module is normal, and improves the safety of the power switch module. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0034] Figure 1 A schematic block diagram of a current detection system based on an inductor element provided in an embodiment of the present invention.

[0035] Figure 2 A circuit diagram of a current detection system based on an inductor element provided in an embodiment of the present invention.

[0036] Figure 3 A circuit diagram of an aging judgment module provided in an embodiment of the present invention.

[0037] Figure 4 A circuit diagram of a detection and adjustment module provided in an embodiment of the present invention.

[0038] Figure 5 A circuit diagram of an output detection module provided in an embodiment of the present invention.

[0039] Figure 6 A circuit diagram of a reference source provided in an embodiment of the present invention.

[0040] Figure 7 A circuit diagram of a drive control module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In one embodiment, see Figure 1 , a current detection system based on an inductor element, comprising: a power switch module 1, a drive control module 2, a current sampling module 3, an output detection module 4, a conduction detection module 5, an aging judgment module 6, a short circuit judgment module 7, a detection and adjustment module 8 and an intelligent control module 9;

[0043] Specifically, the power switch module 1 is connected to the drive control module 2, and is used to receive the drive signal output by the drive control module 2 and adjust the conduction angle of the power switch device, and the power switch device controls the transmission of the connected electric energy and supplies power to the load;

[0044] The drive control module 2 is connected to the intelligent control module 9, the output detection module 4 and the short-circuit judgment module 7, and is used to amplify the pulse signal output by the intelligent control module 9 and output the drive signal. When receiving the first abnormal signal or the second abnormal signal output by the output detection module 4 or the third abnormal signal output by the short-circuit judgment module 7, the drive control module 2 stops outputting the drive signal and lowers the drive potential of the power switch module 1;

[0045] A current sampling module 3, connected to the power switch module 1, for detecting a current change rate of the inductance of the power switch module 1 and outputting a first detection signal;

[0046] The output detection module 4 is connected to the current sampling module 3 and the aging judgment module 6, and is used to set a first fault threshold and a second fault threshold. The voltage of the first fault threshold is greater than the second fault threshold, and when the first detection signal is less than the second fault signal, the first abnormal signal is output, and when the first detection signal is only less than the first fault signal, the second abnormal signal is output, and when the first aging signal, the second aging signal or the third aging signal output by the aging judgment module 6 is received, the voltage value of the first fault threshold and the second fault threshold is increased;

[0047] A conduction detection module 5, connected to the power switch module 1, for detecting the saturation conduction voltage drop of the power switch module 1 and outputting a second detection signal;

[0048] An aging judgment module 6 is connected to the conduction detection module 5 and the short-circuit judgment module 7, and is used to set a first aging threshold, a second aging threshold, and a third aging threshold. When the second detection signal is greater than the first aging threshold, the first aging signal is output; when the second detection signal is greater than the second aging threshold, the second aging signal is output and the first aging signal is stopped from being output; when the second detection signal is greater than the third aging threshold, the third aging signal is output and the first aging signal and the second aging signal are stopped from being output; and when the third abnormal signal output by the short-circuit judgment module 7 is received, the aging degree judgment is stopped;

[0049] A detection and adjustment module 8, connected to the aging judgment module 6, for setting a third fault threshold, and reducing a voltage value of the third fault threshold upon receiving the first aging signal, the second aging signal or the third aging signal;

[0050] A short circuit judgment module 7, connected to the detection and adjustment module 8 and the conduction detection module 5, for outputting a third abnormal signal when the second detection signal is greater than the third fault detection signal;

[0051] The intelligent control module 9 is connected to the aging judgment module 6, the short-circuit judgment module 7 and the output detection module 4, and is used to output a pulse signal, receive a first aging signal, a second aging signal or a third aging signal, and stop outputting the pulse signal when receiving a first abnormal signal, a second abnormal signal or a third abnormal signal, and perform abnormal detection and display when the second abnormal signal and the third abnormal signal are not received at the same time.

[0052] In a specific embodiment, the power switch module 1 may adopt a power switch circuit composed of a power switch device, a load, a power supply interface, etc. to access electric energy and control the transmission state of electric energy; the drive control module 2 may adopt a drive control circuit composed of a diode, a drive device and a logic chip to improve the driving ability of the input signal, and stop the driving work when receiving the first fault signal or the second abnormal signal output by the output detection module 4 or the third abnormal signal output by the short circuit judgment module 7; the current sampling module 3 may adopt a current sampling circuit composed of a detection inductor, a resistor and a diode to detect the inductor current change rate of the power switch module 1 and clamp the detected signal; the output detection module 4 may adopt an output detection circuit composed of a first reference source, a second reference source and a comparator to set the first fault threshold and the second fault threshold, and compare the voltage of the signal output by the current sampling module 3 with the first fault threshold and the second fault threshold, and adjust the voltage of the first fault threshold and the second fault threshold according to the signal output by the aging detection module; The above-mentioned conduction detection module 5 can use an abnormality detection circuit composed of resistors, capacitors, diodes, operational amplifiers, etc. to detect the saturated conduction voltage drop of the power switch module 1 when transmitting electric energy; the above-mentioned aging judgment module 6 can use an aging judgment circuit composed of a comparator, an aging threshold device, a logic chip, etc. to perform three different degrees of aging detection; the above-mentioned short-circuit judgment module 7 can use a short-circuit judgment circuit composed of a comparator to compare the voltage of the output signal of the detection and adjustment module 8 and the conduction detection module 5, and then perform a second type of short-circuit detection; the above-mentioned detection and adjustment module 8 can use a detection and adjustment circuit composed of a resistor, a transistor and a voltage source to set a third fault threshold and adjust the voltage of the third fault threshold according to the signal output by the aging detection module; the above-mentioned intelligent control module 9 can use an intelligent control circuit composed of a single-chip microcomputer, a logic chip and an indicator light, which integrates many components such as an operator, a controller, a memory, and an input and output device to realize signal processing, data storage, module control, timing control and other functions, and can perform a second type of short-circuit abnormality detection and display.

[0053] In another embodiment, see Figure 1 , Figure 2 , Figure 3 and Figure 4 , the power switch module 1 includes a power interface, a first capacitor C1, a first load RL1 and a power switch device;

[0054] Specifically, the first end of the power interface is connected to one end of the first capacitor C1 and is connected to the collector of the power switching device through the first load RL1, the gate of the power switching device is connected to the drive control module 2, the power emitter of the power switching device is connected to the current sampling module 3, and the auxiliary emitter of the power switching device is connected to the other end of the first capacitor C1 and the second end of the power interface.

[0055] In a specific embodiment, the power switch device may be an IGBT.

[0056] Further, the current sampling module 3 includes a first detection inductor L1, a fifth resistor R5, a second power supply VCC2, a sixth diode D6, a sixth resistor R6 and a seventh diode D7;

[0057] Specifically, one end of the first detection inductor L1 is connected to the power emitter of the power switching device, the other end of the first detection inductor L1 is connected to the auxiliary emitter of the power switching device and the first end of the fifth resistor R5, the second end of the fifth resistor R5 is connected to the output detection module 4, the cathode of the seventh diode D7 and the anode of the sixth diode D6, and is connected to the second power supply VCC2 and the cathode of the sixth diode D6 through the sixth resistor R6, and the anode of the seventh diode D7 is grounded.

[0058] In a specific embodiment, the first detection inductor L1 is a parasitic inductor between a power emitter and an auxiliary emitter of a power switch device; the fifth resistor R5, the second power supply VCC2, the sixth diode D6, the sixth resistor R6 and the seventh diode D7 are clamped.

[0059] Further, the conduction detection module 5 includes a second capacitor C2, a first resistor R1, a second resistor R2, a third capacitor C3, a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, a fourth resistor R4, a third resistor R3, a first power supply VCC1 and a first operational amplifier OP1;

[0060] Specifically, one end of the second capacitor C2 is connected to the cathode of the first diode D1 and the collector of the power switching device, and is connected to the other end of the second capacitor C2, one end of the second resistor R2, one end of the third capacitor C3, the anode of the second diode D2 and the cathode of the fourth diode D4 through the first resistor R1, the cathode of the second diode D2 is connected to the cathode of the third diode D3, the anode of the third diode D3 is connected to the cathode of the fifth diode D5, the other end of the third capacitor C3, the other end of the second resistor R2 and the ground, the anode of the fourth diode D4 is connected to the non-inverting end of the first operational amplifier OP1 and the anode of the first diode D1, and is connected to the first power supply VCC1 and one end of the fourth resistor R4 through the third resistor R3, and the other end of the fourth resistor R4 is connected to the anode of the fifth diode D5 and the inverting end of the first operational amplifier OP1.

[0061] In a specific embodiment, the first operational amplifier OP1 may use an OP07 operational amplifier. When the power switch device is turned on, the first diode D1, the fourth diode D4 and the fifth diode D5 are forward-conducted, and the output voltage of the first operational amplifier OP1 is a saturation conduction voltage drop. The first resistor R1, the second capacitor C2, the third capacitor C3 and the second resistor R2 perform voltage division control when the power switch device is turned off.

[0062] Further, the short circuit judgment module 7 includes a first comparator A1; the intelligent control module 9 includes a first controller U1, a fifth logic device J5 and a first indicator light LED1;

[0063] Specifically, the in-phase end of the first comparator A1 is connected to the output end of the first operational amplifier OP1, the inverting end of the first comparator A1 is connected to the detection and adjustment module 8, the first comparator A1 is connected to the aging judgment module 6 and the first end of the seventh resistor, the second end of the seventh resistor is connected to the IO7 end of the first controller U1 and the B end of the fifth logic J5 device, the A end of the fifth logic J5 device is connected to the IO5 end of the first controller U1, the Y end of the fifth logic J5 device is connected to the IO8 end of the first controller U1 and the anode of the first indicator light LED1, and the cathode of the first indicator light LED1 is grounded.

[0064] In a specific embodiment, the first comparator A1 may be a LM358 comparator; the first controller U1 may be a STM32 single-chip microcomputer; and the fifth logic device J5 may be an AND gate chip.

[0065] Further, the aging judgment module 6 includes an aging threshold device, a second comparator A2, a third comparator A3, a fourth comparator A4, a first inverter INV1, a second inverter INV2, a third inverter INV3, a first logic device J1, a second logic device J2 and a third logic device J3;

[0066] Specifically, the first end, the second end and the third end of the aging threshold device are respectively connected to the inverting end of the second comparator A2, the inverting end of the third comparator A3 and the inverting end of the fourth comparator A4, the non-inverting end of the second comparator A2 is connected to the non-inverting end of the third comparator A3, the non-inverting end of the fourth comparator A4 and the output end of the first operational amplifier OP1, the output end of the second comparator A2 is connected to the A end of the first logic device J1, the output end of the third comparator A3 is connected to the input end of the first inverter INV1 and the A end of the second logic device J2, the output end of the fourth comparator A4 is connected to the A end of the first operational amplifier OP1, and the output end of the second comparator A2 is connected to the A end of the first logic device J1. The input end of the second inverter INV2 and the A end of the third logic device J3, the B end of the first logic device J1, the B end of the second logic device J2 and the B end of the third logic device J3 are respectively connected to the output end of the first inverter INV1, the output end of the second inverter INV2 and the output end of the third inverter INV3, the input end of the third inverter INV3 is connected to the output end of the first comparator A1, the Y end of the first logic device J1, the Y end of the second logic device J2 and the Y end of the third logic device J3 are respectively connected to the IO2 end, IO3 end and IO4 end of the first controller U1.

[0067] In a specific embodiment, the above-mentioned aging threshold device can be composed of a reference power supply and a resistor, providing a first aging threshold, a second aging threshold and a third aging threshold, wherein the voltage of the first aging threshold is greater than the voltage of the second aging threshold, the voltage of the third aging threshold is greater than the voltage of the second aging threshold, the first aging threshold represents the early aging stage, the second aging threshold represents the late aging stage, and the third aging threshold represents the critical aging time; the above-mentioned first inverter INV1, the second inverting end and the third inverting end can all use NOT gate chips, the first logic chip, the second logic chip and the third logic chip can all use AND gate chips; the above-mentioned second comparator A2, the third comparator A3 and the fourth comparator A4 can all use LM358 comparators.

[0068] Further, the detection and adjustment module 8 includes a third power supply VCC3, an eighth resistor R8, a ninth resistor R9, a first switch tube V1, a second switch tube V2, a third switch tube V3, a tenth resistor R10, an eleventh resistor R11 and a twelfth resistor R12;

[0069] Specifically, the third power supply VCC3 is connected to one end of the ninth resistor R9, the in-phase end of the first comparator A1, the collector of the first switch tube V1, the collector of the second switch tube V2 and the collector of the third switch tube V3 through the eighth resistor R8; the emitter of the first switch tube V1 is connected to the other end of the ninth resistor R9, one end of the eleventh resistor R11, one end of the twelfth resistor R12 and the ground through the tenth resistor R10; the other end of the eleventh resistor R11 and the other end of the twelfth resistor R12 are respectively connected to the emitter of the second switch tube V2 and the emitter of the third switch tube V3; the base of the first switch tube V1, the base of the second switch tube V2 and the base of the third switch tube V3 are respectively connected to the Y end of the first logic device J1, the Y end of the second logic device J2 and the Y end of the third logic device J3.

[0070] In a specific embodiment, the third power supply VCC3, the eighth resistor R8 and the ninth resistor R9 set the third fault threshold; the first switch tube V1, the second switch tube V2 and the third switch tube V3 can all use NPN type transistors, and respectively cooperate with the tenth resistor R10, the eleventh resistor R11 and the twelfth resistor R12 to adjust the third fault threshold, and the third fault threshold voltage when the first switch tube V1 is turned on is greater than the third fault threshold voltage when the second switch tube V2 is turned on, which is greater than the third fault threshold voltage when the third switch tube V3 is turned on.

[0071] In another embodiment, see Figure 1 , Figure 2 , Figure 3 , Figure 5 , Figure 6 and Figure 7 , the output detection module 4 includes a first-class reference source, a second-class reference source, a seventh switch tube V7, a fifth comparator A5, a sixth comparator A6, a fourth inverter INV4 and a fifth inverter INV5;

[0072] Specifically, the first end of the first type of reference source is connected to the first end of the second type of reference source and the Y end of the first logic device J1, the second end of the first type of reference source is connected to the second end of the second type of reference source and the Y end of the second logic device J2, the third end of the first type of reference source is connected to the third end of the second type of reference source and the Y end of the third logic device J3, the fourth end of the first type of reference source is connected to the inverting end of the fifth comparator A5, the inverting end of the sixth comparator A6 is connected to the fourth end of the second type of reference source, the output end of the fifth comparator A5 and the output end of the sixth comparator A6 are respectively connected to the input end of the fourth inverter INV4 and the input end of the fifth inverter INV5, the output end of the fourth inverter INV4 is connected to the IO5 end of the first controller U1 and the base of the seventh switch tube V7, the collector of the seventh switch tube V7 is connected to the output end of the fifth inverter INV5 and the IO6 end of the first controller U1, the emitter of the seventh switch tube V7 is grounded, and the in-phase end of the fifth comparator A5 is connected to the in-phase end of the sixth comparator A6 and the second end of the fifth resistor R5.

[0073] In a specific embodiment, the fifth comparator A5 and the sixth comparator A6 can both use LM358 comparators; the fourth inverter INV4 and the fifth inverter INV5 can both use NOT gate chips; the first type of reference source sets the second fault threshold, the second type of reference source sets the first fault threshold, the first fault threshold voltage is greater than the second fault threshold voltage, and the circuit composition structure of the first type of reference source is the same as the circuit composition structure of the second type of reference source.

[0074] Further, a type of reference source includes a fourth power supply VCC4, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a fourth switch tube V4, a fifth switch tube V5 and a sixth switch tube V6;

[0075] Specifically, the fourth power supply VCC4 connects the collector of the fourth switch tube V4, the collector of the fifth switch tube V5 and the collector of the sixth switch tube V6, and connects the inverting end of the fifth comparator A5, one end of the seventeenth resistor R17, one end of the eighteenth resistor R18, one end of the nineteenth resistor R19 and one end of the sixteenth resistor R16 through the fifteenth resistor R15. The other end of the sixteenth resistor R16 is grounded, the other end of the seventeenth resistor R17, the other end of the eighteenth resistor R18 and the other end of the nineteenth resistor R19 are respectively connected to the emitter of the fourth switch tube V4, the emitter of the fifth switch tube V5 and the emitter of the sixth switch tube V6, and the base of the fourth switch tube V4, the base of the fifth switch tube V5 and the base of the sixth switch tube V6 are respectively connected to the Y end of the first logic device J1, the Y end of the second logic device J2 and the Y end of the third logic device J3.

[0076] In a specific embodiment, the fourth power supply VCC4, the fifteenth resistor R15 and the sixteenth resistor R16 set the first fault threshold; the fourth switch tube V4, the fifth switch tube V5 and the sixth switch tube V6 can all be NPN-type transistors, which cooperate with the seventeenth resistor R17, the eighteenth resistor R18 and the nineteenth resistor R19 to adjust the voltage of the first fault threshold, and the first fault threshold voltage when the fourth switch tube V4 is turned on is less than the first fault threshold voltage when the fifth switch tube V5 is turned on, which is less than the first fault threshold voltage when the sixth switch tube V6 is turned on.

[0077] Further, the driving control module 2 includes a fourth logic device J4, a driving device, an eighth diode D8, a ninth diode D9 and a tenth diode D10;

[0078] Specifically, the A end of the fourth logic device J4 is connected to the IO1 end of the first controller U1, the B end of the fourth logic device J4 is connected to the cathode of the eighth diode D8, the cathode of the ninth diode D9 and the cathode of the tenth diode D10, and the anode of the eighth diode D8, the anode of the ninth diode D9 and the anode of the tenth diode D10 are respectively connected to the second end of the seventh resistor, the output end of the fourth inverter INV4 and the output end of the fifth inverter INV5.

[0079] In a specific embodiment, the fourth logic device J4 may be an XOR gate chip; the driving device is composed of a discrete NPN transistor / PNP transistor complementary output stage.

[0080] In a current detection system based on an inductor element of the present embodiment, a pulse signal is outputted from the IO1 terminal of the first controller U1, the fourth logic device J4 and the driving device improve the driving capability of the pulse signal and output a driving signal to control the conduction angle of the power switch device, and adjust the power of the first load RL1. When the power switch device is not turned on, the first resistor R1, the second resistor R2, the first capacitor C1 and the second capacitor C2 divide the voltage. When the power switch device is turned on, the first diode D1, the fourth diode D4 and the fifth diode are forward-conducted, and the output voltage of the first operational amplifier OP1 is a saturated conduction voltage drop, i.e., a second detection signal. During the period when the second detection signal is not greater than the first aging threshold value set by the aging threshold value device, if a type II short circuit occurs directly, the second detection signal The value of the first detection inductor L1 is greater than the third fault threshold value set by the detection and adjustment module 8. At this time, the current change rate of the first detection inductor L1 detected is clamped by the fifth resistor R5, the sixth resistor R6, the second power supply VCC2, the sixth diode D6 and the seventh diode D7, and the first detection signal is output. The first detection signal will be only less than the first fault signal set by the second-class reference source. The sixth comparator A6 outputs a low level, and the fifth inverter INV5 inverts and outputs a second abnormal signal. If a second-class short circuit occurs, the first comparator A1 or the fifth inverter INV5 has a high-level signal that does not output a high-level signal, the Y end of the fifth logic J5 will output a high level, and the first indicator LED1 will be lit, and the second-class short circuit detection abnormality display will be performed. When a first-class short circuit occurs, the first detection When the detection signal is less than the second fault signal set by the first-class reference source, the fourth inverter INV4 outputs a high level, i.e., the first abnormal signal, which controls the seventh switch tube V7 to be turned on, and the output end of the fifth inverter INV5 is pulled low. When the fourth inverter INV4, the fifth inverter INV5 or the first comparator A1 outputs a high level, the fourth logic device J4 stops working and the first controller U1 stops outputting the pulse signal. When there is no first-class short circuit or second-class short circuit, if the second detection signal is greater than the first aging threshold set by the aging threshold device, it means that the power switch device is in the early stage of aging. At this time, the first comparator A1 outputs a high level, and the first logic chip outputs the first aging signal, which controls the second-class reference source to adjust the set first fault threshold, and controls the first switch tube V1. and the fourth switch tube V4 are turned on, the first switch tube V1 cooperates with the tenth resistor R10, the third power supply VCC3, the eighth resistor R8 and the ninth resistor R9 to reset the third fault threshold, the fourth switch tube V4 cooperates with the fourth power supply VCC4, the fifteenth resistor R15, the sixteenth resistor R16 and the seventeenth resistor R17 to reset the second fault threshold, and then adjusts the second type short circuit detection accuracy of the collector of the power switch device, and adjusts the first type short circuit and the second type short circuit detection accuracy of the emitter of the power switch device. Similarly, if the second detection signal is greater than the second aging threshold set by the aging, the power switch device is in the late aging stage, and the second switch tube V2 and the fifth switch tube V5 are controlled to be turned on, and the first fault threshold, the second fault threshold and the third fault threshold are further adjusted.When the second detection signal is greater than the third aging threshold, the power switch device is in a critical aging state, the third switch tube V3 and the sixth switch tube V6 are controlled to be turned on, and the first fault threshold, the second fault threshold and the third fault threshold are adjusted again to improve the safety of the power switch device, and when the second aging threshold is output, the first aging threshold is stopped from being output, when the third aging threshold is output, the first aging threshold and the second aging threshold are stopped from being output, and when the third abnormal signal is output, the first aging threshold, the second aging threshold and the third aging threshold are stopped from being output.

[0081] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0082] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A current detection system based on an inductor element, characterized in that: The current detection system based on inductor elements includes: a power switch module, a drive control module, a current sampling module, an output detection module, a conduction detection module, an aging judgment module, a short circuit judgment module, a detection and adjustment module and an intelligent control module; The power switch module is connected to the drive control module and is used to receive the drive signal output by the drive control module and adjust the conduction angle of the power switch device, and the power switch device controls the transmission of the connected electric energy and supplies power to the load; The drive control module is connected to the intelligent control module, the output detection module and the short-circuit judgment module, and is used to amplify the pulse signal output by the intelligent control module and output the drive signal, and when receiving the first abnormal signal or the second abnormal signal output by the output detection module or the third abnormal signal output by the short-circuit judgment module, stop outputting the drive signal and lower the drive potential of the power switch module; The current sampling module is connected to the power switch module and is used to detect the current change rate of the inductance of the power switch module and output a first detection signal; The output detection module is connected to the current sampling module and the aging judgment module, and is used to set a first fault threshold and a second fault threshold, the voltage of the first fault threshold is greater than the second fault threshold, and when the first detection signal is less than the second fault threshold, the first abnormal signal is output, and when the first detection signal is only less than the first fault threshold, the second abnormal signal is output, and when the first aging signal, the second aging signal or the third aging signal output by the aging judgment module is received, the voltage values ​​of the first fault threshold and the second fault threshold are increased; The conduction detection module is connected to the power switch module and is used to detect the saturation conduction voltage drop of the power switch module and output a second detection signal; The aging judgment module is connected to the conduction detection module and the short-circuit judgment module, and is used to set a first aging threshold, a second aging threshold, and a third aging threshold. When the second detection signal is greater than the first aging threshold, the first aging signal is output; when the second detection signal is greater than the second aging threshold, the second aging signal is output and the first aging signal is stopped from being output; when the second detection signal is greater than the third aging threshold, the third aging signal is output and the first aging signal and the second aging signal are stopped from being output; when the third abnormal signal output by the short-circuit judgment module is received, the aging degree judgment is stopped; The detection and adjustment module is connected to the aging judgment module and is used to set a third fault threshold value, and when receiving the first aging signal, the second aging signal or the third aging signal, reduce the voltage value of the third fault threshold value; The short circuit judgment module is connected to the detection and adjustment module and the conduction detection module, and is used to output a third abnormal signal when the second detection signal is greater than the third fault detection signal; The intelligent control module is connected to the aging judgment module, the short-circuit judgment module and the output detection module, and is used to output a pulse signal, receive a first aging signal, a second aging signal or a third aging signal, stop outputting the pulse signal when receiving a first abnormal signal, a second abnormal signal or a third abnormal signal, and perform abnormal detection and display when the second abnormal signal and the third abnormal signal are not received at the same time.

2. A current detection system based on an inductor element according to claim 1, characterized in that: The power switch module includes a power interface, a first capacitor, a first load and a power switch device; The first end of the power interface is connected to one end of the first capacitor and is connected to the collector of the power switching device through the first load, the gate of the power switching device is connected to the drive control module, the power emitter of the power switching device is connected to the current sampling module, and the auxiliary emitter of the power switching device is connected to the other end of the first capacitor and the second end of the power interface.

3. A current detection system based on an inductor element according to claim 2, characterized in that: The current sampling module includes a first detection inductor, a fifth resistor, a second power supply, a sixth diode, a sixth resistor and a seventh diode; One end of the first detection inductor is connected to the power emitter of the power switching device, the other end of the first detection inductor is connected to the auxiliary emitter of the power switching device and the first end of the fifth resistor, the second end of the fifth resistor is connected to the output detection module, the cathode of the seventh diode and the anode of the sixth diode, and is connected to the second power supply and the cathode of the sixth diode through the sixth resistor, and the anode of the seventh diode is grounded.

4. The current detection system based on an inductor element according to claim 3, characterized in that: The conduction detection module includes a second capacitor, a first resistor, a second resistor, a third capacitor, a first diode, a second diode, a third diode, a fourth diode, a fifth diode, a fourth resistor, a third resistor, a first power supply and a first operational amplifier; One end of the second capacitor is connected to the cathode of the first diode and the collector of the power switching device and is connected to the other end of the second capacitor, one end of the second resistor, one end of the third capacitor, the anode of the second diode and the cathode of the fourth diode through the first resistor, the cathode of the second diode is connected to the cathode of the third diode, the anode of the third diode is connected to the cathode of the fifth diode, the other end of the third capacitor, the other end of the second resistor and the ground, the anode of the fourth diode is connected to the in-phase terminal of the first operational amplifier and the anode of the first diode and is connected to the first power supply and one end of the fourth resistor through the third resistor, and the other end of the fourth resistor is connected to the anode of the fifth diode and the inverting terminal of the first operational amplifier.

5. The current detection system based on inductor element according to claim 4, characterized in that: The short circuit judgment module includes a first comparator; the intelligent control module includes a first controller, a fifth logic device and a first indicator light; the first controller is an STM32 single chip microcomputer; the fifth logic device is an AND gate chip; The non-inverting end of the first comparator is connected to the output end of the first operational amplifier, the inverting end of the first comparator is connected to the detection and adjustment module, the first comparator is connected to the aging judgment module and the first end of the seventh resistor, the second end of the seventh resistor is connected to the IO7 end of the first controller and the B end of the fifth logic device, the A end of the fifth logic device is connected to the IO5 end of the first controller, the Y end of the fifth logic device is connected to the IO8 end of the first controller and the anode of the first indicator light, and the cathode of the first indicator light is grounded.

6. The current detection system based on an inductor element according to claim 5, characterized in that: The aging judgment module includes an aging threshold device, a second comparator, a third comparator, a fourth comparator, a first inverter, a second inverter, a third inverter, a first logic device, a second logic device and a third logic device; the first logic device, the second logic device and the third logic device are all AND gate chips; The first end, the second end and the third end of the aging threshold device are respectively connected to the inverting end of the second comparator, the inverting end of the third comparator and the inverting end of the fourth comparator, the non-inverting end of the second comparator is connected to the non-inverting end of the third comparator, the non-inverting end of the fourth comparator and the output end of the first operational amplifier, the output end of the second comparator is connected to the A end of the first logic device, the output end of the third comparator is connected to the input end of the first inverter and the A end of the second logic device, the output end of the fourth comparator is connected to the input end of the second inverter and the A end of the third logic device, the B end of the first logic device, the B end of the second logic device and the B end of the third logic device are respectively connected to the output end of the first inverter, the output end of the second inverter and the output end of the third inverter, the input end of the third inverter is connected to the output end of the first comparator, and the Y end of the first logic device, the Y end of the second logic device and the Y end of the third logic device are respectively connected to the IO2 end, the IO3 end and the IO4 end of the first controller.

7. The current detection system based on an inductor element according to claim 6, characterized in that: The detection and adjustment module includes a third power supply, an eighth resistor, a ninth resistor, a first switch tube, a second switch tube, a third switch tube, a tenth resistor, an eleventh resistor and a twelfth resistor; The third power supply is connected to one end of the ninth resistor, the in-phase end of the first comparator, the collector of the first switch tube, the collector of the second switch tube and the collector of the third switch tube through the eighth resistor. The emitter of the first switch tube is connected to the other end of the ninth resistor, one end of the eleventh resistor, one end of the twelfth resistor and the ground through the tenth resistor. The other end of the eleventh resistor and the other end of the twelfth resistor are respectively connected to the emitter of the second switch tube and the emitter of the third switch tube. The base of the first switch tube, the base of the second switch tube and the base of the third switch tube are respectively connected to the Y end of the first logic device, the Y end of the second logic device and the Y end of the third logic device.

8. The current detection system based on inductor element according to claim 7, characterized in that: The output detection module includes a first-class reference source, a second-class reference source, a seventh switch tube, a fifth comparator, a sixth comparator, a fourth inverter and a fifth inverter; The first end of the first type of reference source is connected to the first end of the second type of reference source and the Y end of the first logic device, the second end of the first type of reference source is connected to the second end of the second type of reference source and the Y end of the second logic device, the third end of the first type of reference source is connected to the third end of the second type of reference source and the Y end of the third logic device, the fourth end of the first type of reference source is connected to the inverting end of the fifth comparator, the inverting end of the sixth comparator is connected to the fourth end of the second type of reference source, the output end of the fifth comparator and the output end of the sixth comparator are respectively connected to the input end of the fourth inverter and the input end of the fifth inverter, the output end of the fourth inverter is connected to the IO5 end of the first controller and the base of the seventh switch tube, the collector of the seventh switch tube is connected to the output end of the fifth inverter and the IO6 end of the first controller, the emitter of the seventh switch tube is grounded, and the non-inverting end of the fifth comparator is connected to the non-inverting end of the sixth comparator and the second end of the fifth resistor.

9. The current detection system based on an inductor element according to claim 8, characterized in that: The first type of reference source includes a fourth power supply, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a fourth switch tube, a fifth switch tube and a sixth switch tube; The fourth power supply is connected to the collector of the fourth switch tube, the collector of the fifth switch tube and the collector of the sixth switch tube, and is connected to the inverting end of the fifth comparator, one end of the seventeenth resistor, one end of the eighteenth resistor, one end of the nineteenth resistor and one end of the sixteenth resistor through the fifteenth resistor. The other end of the sixteenth resistor is grounded, and the other end of the seventeenth resistor, the other end of the eighteenth resistor and the other end of the nineteenth resistor are respectively connected to the emitter of the fourth switch tube, the emitter of the fifth switch tube and the emitter of the sixth switch tube, and the base of the fourth switch tube, the base of the fifth switch tube and the base of the sixth switch tube are respectively connected to the Y end of the first logic device, the Y end of the second logic device and the Y end of the third logic device.

10. The current detection system based on inductor element according to claim 8, characterized in that: The drive control module includes a fourth logic device, a drive device, an eighth diode, a ninth diode and a tenth diode; the fourth logic device is an XOR gate chip; The A end of the fourth logic device is connected to the IO1 end of the first controller, the B end of the fourth logic device is connected to the cathode of the eighth diode, the cathode of the ninth diode and the cathode of the tenth diode, the anode of the eighth diode, the anode of the ninth diode and the anode of the tenth diode are respectively connected to the second end of the seventh resistor, the output end of the fourth inverter and the output end of the fifth inverter.

Images