Temperature and voltage signal detection method based on multi-channel IGBT module

Abstract

This invention relates to the field of IGBT temperature detection, and more specifically, to a method for detecting temperature voltage signals based on multiple IGBT modules, comprising the following steps: Step 1, integrating a high-precision reference voltage source on each IGBT module, and controlling the high-precision reference voltage source to simultaneously provide a voltage of the same value to each corresponding IGBT module; Step 2, connecting a high-precision voltage divider circuit between the high-precision reference voltage source and ground, the intermediate node of the high-precision voltage divider circuit generating a raw voltage signal that varies with temperature based on the DC voltage value input from the high-precision reference voltage source; Step 3, connecting the raw voltage signal of the high-precision voltage divider circuit to the non-inverting input terminals of multiple rectifier circuits, and connecting the final output terminals of the multiple rectifier circuits to the common output node of each IGBT module; Step 4, comparing the temperature voltage signals at the final output terminals of the multiple rectifier circuits, and outputting the temperature voltage signal with the maximum value.

Description

Technical Field

[0001] This invention relates to the field of IGBT temperature detection, and more specifically, to a method for detecting temperature and voltage signals based on a multi-channel IGBT module. Background Technology

[0002] In power electronic equipment (such as frequency converters, inverters, servo drives, etc.), IGBTs (Insulated Gate Bipolar Transistors) are core power switching devices. Their operating junction temperature directly affects the reliability and service life of the system. IGBT modules generate a lot of heat during operation. If the junction temperature exceeds the safety threshold, it may lead to device performance degradation or even permanent damage. Therefore, real-time temperature monitoring of IGBT modules and timely triggering of overheat protection are key technologies to ensure the safe and stable operation of equipment.

[0003] Currently, common IGBT temperature monitoring solutions mainly rely on NTC (negative temperature coefficient) thermistors integrated inside the module. Traditional implementation methods are generally divided into the following two categories: 1. Multi-channel independent detection and software gating scheme This solution configures an independent signal conditioning circuit (such as a voltage divider network, operational amplifier, etc.) for each NTC thermistor, and connects multiple analog voltage signals to multiple analog-to-digital converter (ADC) channels of a microcontroller (MCU). The MCU polls and compares the sampled values ​​of each ADC through software, and selects the voltage value corresponding to the highest temperature as the basis for overheat protection judgment.

[0004] However, this solution has the following significant drawbacks: limited response speed: from signal sampling and software processing to protection action execution, the entire process relies on software scheduling. In fault conditions with rapidly rising temperatures, the protection delay is long, making it difficult to meet the rapid protection requirements under extreme conditions.

[0005] 2. Diode Analog Gating Scheme To simplify the system structure and reduce reliance on MCU resources, existing technologies have proposed using ordinary diodes to construct "wired-AND" logic circuits. Multiple NTC voltage divider signals are connected in parallel to the same detection node through diodes. Utilizing the unidirectional conductivity of diodes, theoretically only the signal with the highest voltage is allowed to conduct and output, thereby achieving hardware selection of the highest temperature signal.

[0006] However, this scheme has serious shortcomings in practical applications: First, the measurement accuracy is poor: when a common diode is conducting, there is a forward voltage drop of about 0.6–0.7V, which will be directly superimposed on the NTC voltage divider signal, introducing a fixed offset error. In addition, the forward voltage drop of the diode itself has a negative temperature coefficient, which drifts with changes in ambient temperature, causing further distortion of the temperature detection results, making it difficult to meet the temperature measurement requirements of high-precision and high-reliability applications. Second, the gating reliability is low: when the voltages of multiple signals are close, the conduction state of the diode may be unstable and easily affected by parasitic parameters and noise interference, affecting the accuracy of the gating results.

[0007] Therefore, existing technical solutions have limitations in terms of cost, accuracy, response speed, and reliability. There is an urgent need for a new detection circuit that can combine hardware simplification, fast response, and high-precision temperature gating to meet the high standards of modern power electronic equipment for IGBT module temperature monitoring. Therefore, it is necessary to propose a temperature and voltage signal detection method based on multi-channel IGBT modules to solve the above problems. Summary of the Invention

[0008] To overcome at least one of the defects (deficiencies) of the prior art, the present invention provides a method for detecting temperature and voltage signals based on a multi-channel IGBT module.

[0009] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A method for detecting temperature and voltage signals based on a multi-channel IGBT module, comprising the following steps: Step 1: Integrate a high-precision reference voltage source on each IGBT module, and control the high-precision reference voltage source to simultaneously provide a voltage of the same value to each corresponding IGBT module. Step 2: Connect the high-precision voltage divider circuit between the high-precision reference voltage source and ground. The intermediate node of the high-precision voltage divider circuit generates a raw voltage signal that varies with temperature based on the DC voltage value input from the high-precision reference voltage source. Step 3: Connect the original voltage signal of the high-precision voltage divider circuit to the non-inverting input of multiple rectifier circuits, and connect the final output of multiple rectifier circuits to the common output node of each IGBT module. Step 4: By comparing the temperature and voltage signals at the final output terminals of multiple rectifier circuits, the temperature and voltage signal with the maximum value is output. Furthermore, in step 1, the voltage is a DC voltage.

[0010] Furthermore, in step 2, the high-precision voltage divider circuit includes a fixed resistor and an NTC thermistor; One end of the fixed resistor is connected to a high-precision reference voltage source, and the other end is connected to ground through an NTC thermistor; The junction between the fixed resistor and the NTC thermistor is connected to the input terminal of the rectifier circuit.

[0011] Furthermore, in step 3, the rectifier circuit includes an operational amplifier and a feedback diode. The non-inverting input of the operational amplifier is connected to the junction between the fixed resistor and the NTC thermistor. The output of the operational amplifier is connected to the final output of the IGBT module through the feedback diode, and is also connected to the inverting input through the feedback path.

[0012] Furthermore, step 4 also includes: Step 51: Connect an MCU microcontroller and an IGBT junction temperature observer to each IGBT module. Step 52: The IGBT junction temperature observer of the IGBT module that outputs the maximum value temperature voltage signal detects the temperature voltage signal of the IGBT module that outputs the maximum value temperature voltage signal in real time. Step 53: The IGBT junction temperature observer of the IGBT module with the non-maximum output temperature voltage signal performs intermittent sampling inspection of the temperature voltage signal of the IGBT module with the non-maximum output temperature voltage signal. Step 54: The MCU microcontroller records the maximum temperature and voltage signal value of each IGBT module during the sampling period in real time based on the intermittent sampling inspection records, and compares it with the maximum temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal during the corresponding sampling period. Step 55: The MCU microcontroller records the average temperature and voltage signal value of each IGBT module during the sampling period in real time based on the intermittent sampling inspection records, and compares it with the minimum temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal during the corresponding sampling period. Step 56: The MCU microcontroller calculates the difference between the temperature and voltage signal with the maximum output value and the temperature and voltage signal with the maximum output value during sampling, and obtains the difference deviation rate. Step 57: The MCU microcontroller compares the temperature and voltage signal with the maximum output value with the minimum temperature and voltage signal with the non-maximum output value during sampling and the average temperature and voltage signal value of the IGBT module during the sampling period to calculate the rate of change of the difference. Step 58: The ratio of the temperature voltage signal with the maximum output value of the IGBT module is obtained by using the formula: difference change rate / difference deviation rate.

[0013] Furthermore, after step 58, the following is also included: Step 61: The MCU microcontroller sorts the real-time temperature and voltage signal values ​​of all IGBT modules sampled at the same time. Step 62: When the real-time temperature difference between the IGBT module with the non-maximum output temperature voltage signal and the IGBT module with the maximum output temperature voltage signal reaches the set warning detection value, the IGBT module with the maximum output temperature voltage signal will be randomly sampled again between adjacent standard sampling times. Step 63: When the real-time temperature difference between the IGBT module with the non-maximum output temperature voltage signal and the IGBT module with the maximum output temperature voltage signal reaches the set alarm detection value, the load change of the IGBT module and its temperature voltage signal are monitored in real time.

[0014] Furthermore, in step 63, the MCU microcontroller monitors in real time the number of loads of the IGBT modules corresponding to the temperature voltage signal value close to the final output terminal, as well as their corresponding power protection and temperature voltage signal changes, and monitors in real time the number of loads of the IGBT modules with the maximum output temperature voltage signal, as well as their corresponding power protection and temperature voltage signal changes.

[0015] Furthermore, after step 63, the following is also included: When a new load is needed, the MCU microcontroller identifies the quantity and power of the load, and based on the temperature and voltage signals at the final output terminals of multiple rectifier circuits, recommends that the load be installed sequentially on the IGBT module with the largest difference between the temperature and voltage signals at the final output terminals of the multiple rectifier circuits.

[0016] Furthermore, the MCU microcontroller is equipped with a wireless communicator.

[0017] Compared with the prior art, the beneficial effects of the technical solution of the present invention are: This invention discloses a temperature and voltage signal detection method based on multi-channel IGBT modules. It integrates a high-precision reference voltage source on each IGBT module and connects a high-precision voltage divider circuit between the reference voltage source and ground. The intermediate node of the high-precision voltage divider circuit generates a raw voltage signal that varies with temperature based on the DC voltage input from the reference voltage source. This raw voltage signal is then connected to the non-inverting input of multiple rectifier circuits, and the final outputs of these rectifier circuits are connected to the common output node of each IGBT module. By comparing the temperature and voltage signals at the final outputs of the multiple rectifier circuits, the maximum temperature and voltage signal is output. Therefore, when more channels need to be added for signal processing, only additional signal processing channels with the same structure are needed to easily expand the number of temperature monitoring channels, offering good flexibility. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the temperature and voltage signal detection method for multi-channel IGBT modules in this invention.

[0019] Figure 2 This is a circuit diagram for temperature and voltage signal detection of the IGBT module in this invention.

[0020] Figure 3 This is a circuit diagram for temperature and voltage signal detection of the multi-channel IGBT module in this invention.

[0021] In the diagram, 1 is a fixed resistor, 2 is an NTC thermistor, 3 is a high-precision reference voltage source, 4 is an operational amplifier, and 5 is a feedback diode. Detailed Implementation

[0022] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this patent. To better illustrate this embodiment, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The technical solution of this invention will be further described below with reference to the accompanying drawings and embodiments.

[0024] like Figure 1-3 As shown, a method for detecting temperature and voltage signals based on a multi-channel IGBT module includes the following steps: Step 1: Integrate a high-precision reference voltage source on each IGBT module, and control the high-precision reference voltage source to simultaneously provide a voltage of the same value to each corresponding IGBT module. Step 2: Connect the high-precision voltage divider circuit between the high-precision reference voltage source and ground. The intermediate node of the high-precision voltage divider circuit generates a raw voltage signal that varies with temperature based on the DC voltage value input from the high-precision reference voltage source. Step 3: Connect the original voltage signal of the high-precision voltage divider circuit to the non-inverting input of multiple rectifier circuits, and connect the final output of multiple rectifier circuits to the common output node of each IGBT module. Step 4: By comparing the temperature and voltage signals at the final output terminals of multiple rectifier circuits, the temperature and voltage signal with the maximum value is output. In step 1 of this invention, the voltage is a DC voltage.

[0025] In step 2 of the present invention, the high-precision voltage divider circuit includes a fixed resistor 1 and an NTC thermistor 2; one end of the fixed resistor is connected to the high-precision reference voltage source 3, and the other end is connected to ground through the NTC thermistor; the junction between the fixed resistor and the NTC thermistor is connected to the input terminal of the rectifier circuit.

[0026] In step 3 of the present invention, the rectifier circuit includes an operational amplifier 4 and a feedback diode 5. The non-inverting input terminal of the operational amplifier is connected to the junction between the fixed resistor and the NTC thermistor. The output terminal of the operational amplifier is connected to the final output terminal of the IGBT module through the feedback diode, and is also connected to the inverting input terminal through the feedback path.

[0027] In addition to the above, step 4 also includes: Step 51: Connect an MCU microcontroller and an IGBT junction temperature observer to each IGBT module. Step 52: The IGBT junction temperature observer of the IGBT module that outputs the maximum value temperature voltage signal detects the temperature voltage signal of the IGBT module that outputs the maximum value temperature voltage signal in real time. Step 53: The IGBT junction temperature observer of the IGBT module with the non-maximum output temperature voltage signal performs intermittent sampling inspection of the temperature voltage signal of the IGBT module with the non-maximum output temperature voltage signal. Step 54: The MCU microcontroller records the maximum temperature and voltage signal value of each IGBT module during the sampling period in real time based on the intermittent sampling inspection records, and compares it with the maximum temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal during the corresponding sampling period. Step 55: The MCU microcontroller records the average temperature and voltage signal value of each IGBT module during the sampling period in real time based on the intermittent sampling inspection records, and compares it with the minimum temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal during the corresponding sampling period. Step 56: The MCU microcontroller calculates the difference between the temperature and voltage signal with the maximum output value and the temperature and voltage signal with the maximum output value during sampling, and obtains the difference deviation rate. Step 57: The MCU microcontroller compares the temperature and voltage signal with the maximum output value with the minimum temperature and voltage signal with the non-maximum output value during sampling and the average temperature and voltage signal value of the IGBT module during the sampling period to calculate the rate of change of the difference. Step 58: The ratio of the temperature voltage signal with the maximum output value of the IGBT module is obtained by using the formula: difference change rate / difference deviation rate.

[0028] In this invention, the method further includes the following after step 58: Step 61: The MCU microcontroller sorts the real-time temperature and voltage signal values ​​of all IGBT modules sampled at the same time. Step 62: When the real-time temperature difference between the IGBT module with the non-maximum output temperature voltage signal and the IGBT module with the maximum output temperature voltage signal reaches the set warning detection value, the IGBT module with the maximum output temperature voltage signal will be randomly sampled again between adjacent standard sampling times. Step 63: When the real-time temperature difference between the IGBT module with the non-maximum output temperature voltage signal and the IGBT module with the maximum output temperature voltage signal reaches the set alarm detection value, the load change of the IGBT module and its temperature voltage signal are monitored in real time.

[0029] In step 63, the MCU microcontroller monitors in real time the number of IGBT modules whose temperature voltage signal values ​​are close to the final output, as well as their corresponding power protection and temperature voltage signal changes. It also monitors the real-time number of IGBT modules whose temperature voltage signal values ​​are close to the final output, as well as their corresponding power protection and temperature voltage signal changes. In this invention, after step 63, the following further step is added: when a new load is needed, the MCU microcontroller identifies the number and power of the load, and based on the temperature voltage signals at the final outputs of multiple rectifier circuits, recommends that the load be installed sequentially on the IGBT module with the largest difference between its temperature voltage signal and the final output of the multiple rectifier circuits. In practical applications, a wireless communicator is provided on the MCU microcontroller.

[0030] Example In this embodiment, the circuit system includes at least two IGBT modules with identical structures. A high-precision reference voltage source is integrated into each IGBT module, and the high-precision reference voltage source is controlled to simultaneously provide each corresponding IGBT module with a DC voltage of the same value, such as 3.3V. A high-precision voltage divider circuit is connected between the high-precision reference voltage source and ground. The intermediate node of the high-precision voltage divider circuit generates a temperature-varying original voltage signal based on the DC voltage value input from the high-precision reference voltage source. This original voltage signal is then connected to the non-inverting input of multiple rectifier circuits, and the final output of the multiple rectifier circuits is connected to the common output node of each IGBT module. By comparing the temperature and voltage signals at the final output terminals of multiple rectifier circuits, the maximum temperature and voltage signal is output. In this embodiment, the high-precision voltage divider circuit includes a fixed resistor and an NTC thermistor. One end of the fixed resistor is connected to a high-precision reference voltage source, and the other end is connected to ground through the NTC thermistor. The junction between the fixed resistor and the NTC thermistor is connected to the input terminal of the rectifier circuit. The rectifier circuit includes an operational amplifier and a feedback diode. The non-inverting input terminal of the operational amplifier is connected to the junction between the fixed resistor and the NTC thermistor. The output terminal of the operational amplifier is connected to the final output terminal of this IGBT module through the feedback diode, and is also connected to the inverting input terminal through the feedback path.

[0031] Working principle: When the Vtemp(n) voltage generated by a certain IGBT module is higher than the voltage of the common output node Vout, the output of the operational amplifier of that channel will quickly become high, causing the feedback diode to be forward biased and turned on. Due to the negative feedback of the operational amplifier, it will dynamically adjust the output so that the voltage of Vtemp(n) is basically equal to the voltage of the inverting input terminal of the operational amplifier (i.e., the output terminal of this unit), thereby eliminating the influence of the forward voltage drop of the feedback diode and realizing the function of an "ideal diode". At this time, the Vtemp(n) voltage of that channel is transmitted to the common output node Vout "without loss".

[0032] Conversely, when the voltage of a certain path, Vtemp(n), is lower than the voltage of the common output node, Vout, the output voltage of its operational amplifier will be lower than Vout, causing the feedback diode to be reverse biased and cut off. This path of the circuit is disconnected from the common output node and will not interfere with the highest voltage signal.

[0033] In this way, among all the temperature detection units connected in parallel to the Vout node, only the one with the highest Vtemp(n) voltage (i.e. the highest temperature) can be turned on and output its voltage signal, while the rest are automatically isolated.

[0034] Taking the monitoring of the channel temperature signals of two IGBT modules as an example, the system includes two identical temperature detection units (Unit 1, Unit 2). For simplicity, only two channels are used as an example, but it can be expanded to N channels. First temperature detection unit (Unit 1): The reference voltage Vref = 3.3V (1% accuracy). The voltage divider circuit consists of a high-precision fixed resistor R1 (1% accuracy) and the thermistor NTC1 inside IGBT1 connected in series. The operational amplifier U1 forms a precision rectifier circuit. The non-inverting input of the operational amplifier U1 is connected to the voltage divider point Vtemp1 of the high-precision fixed resistor R1 and the thermistor NTC1. The output of the operational amplifier U1 is connected to the anode of the feedback diode D1. The cathode of the feedback diode D1 serves as the output of this unit and is connected to the inverting input Vout of the operational amplifier U1.

[0035] The second temperature detection unit (Unit 2) is completely symmetrical in structure to the temperature detection unit Unit 1. It includes a high-precision fixed resistor R2, a thermistor NTC2, an operational amplifier U2, a feedback diode D2, and a common output node Vtemp_max connected to an ADC input pin of the MCU microcontroller.

[0036] Work process: Suppose that at a certain moment, the temperature of IGBT1 is higher than that of IGBT2, i.e., Vtemp1 > Vtemp2. ​​For the first temperature detection unit Unit 1, since Vtemp1 > Vout, the operational amplifier U1 outputs a high level, and the feedback diode D1 is turned on. The negative feedback forces the output voltage (i.e., Vout) of the first temperature detection unit Unit 1 to be infinitely close to Vtemp1. For the second temperature detection unit Unit 2, since Vtemp2 < Vout, the output voltage of the operational amplifier U2 is pulled low, and the feedback diode D2 is turned off due to reverse bias. The first temperature detection unit Unit 2 is isolated from the Vout node. Therefore, Vout = Vtemp1. The voltage sampled by the MCU microcontroller directly reflects the temperature of the higher-temperature IGBT1. When the load changes and causes the temperature of IGBT2 to rise and exceed that of IGBT1, Vtemp2 > Vtemp1. The circuit state will automatically switch, the second temperature detection unit Unit 2 will be turned on, and the first temperature detection unit Unit 1 will be turned off. Vout = Vtemp2, realizing the automatic and seamless switching of the highest temperature signal.

[0037] In addition to achieving automatic and seamless switching of the highest temperature signal, in practical applications, an MCU microcontroller and an IGBT junction temperature observer can be connected to each IGBT module. During operation, the IGBT junction temperature observer of the IGBT module with the maximum output temperature and voltage signal monitors the temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal in real time. Furthermore, during operation, the IGBT junction temperature observer of the IGBT module with a non-maximum output temperature and voltage signal needs to perform intermittent sampling checks. Then, based on the intermittent sampling check records, the MCU microcontroller records in real time the maximum temperature and voltage signal value of each IGBT module during the sampling period and the maximum temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal of the corresponding sampling period. The temperature and voltage signals are compared. The MCU microcontroller, based on intermittent sampling records, records the average temperature and voltage signal value of each IGBT module during the sampling period and compares it with the minimum temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal during the corresponding sampling period. In this embodiment, the MCU microcontroller calculates the difference between the temperature and voltage signal with the maximum output temperature and voltage signal (not the maximum output temperature and voltage signal) during sampling to obtain the difference deviation rate. Then, the MCU microcontroller calculates the difference change rate by comparing the temperature and voltage signal with the minimum temperature and voltage signal (not the maximum output temperature and voltage signal) during sampling with the average temperature and voltage signal value of the IGBT module during the sampling period. Finally, the ratio of the IGBT module to the maximum output temperature and voltage signal is obtained using the formula: difference change rate / difference deviation rate.

[0038] In this invention, the MCU microcontroller can also sort the real-time temperature and voltage signal values ​​of all IGBT modules sampled at the same time. When the real-time temperature difference between the IGBT module with a non-maximum output temperature and voltage signal and the IGBT module with the maximum output temperature and voltage signal reaches a set warning detection value, the IGBT module with the maximum output temperature and voltage signal is randomly sampled again between adjacent standard sampling times. When the real-time temperature difference between the IGBT module with a non-maximum output temperature and voltage signal and the IGBT module with the maximum output temperature and voltage signal reaches a set alarm detection value, the load change and temperature and voltage signal of the IGBT module are monitored in real time.

[0039] During application, the MCU microcontroller monitors in real time the number of IGBT modules with temperature and voltage signal values ​​close to the final output terminal, as well as their corresponding power protection and temperature and voltage signal changes. It also monitors the real-time number of IGBT modules with temperature and voltage signal values ​​of the maximum output value, as well as their corresponding power protection and temperature and voltage signal changes. In this invention, after step 63, the method further includes: when a new load is needed, the MCU microcontroller identifies the number and power of the load, and based on the temperature and voltage signals of the final output terminals of multiple rectifier circuits, recommends that the load be installed sequentially on the IGBT module with the largest difference between the temperature and voltage signals of the final output terminals of multiple rectifier circuits, and connects the MCU microcontroller and the IGBT junction temperature observer to each IGBT module.

[0040] The positional relationships described in the figures are for illustrative purposes only and should not be construed as limiting this patent. Clearly, the above embodiments of the present invention are merely examples to clearly illustrate the invention and are not intended to limit the implementation of the invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of this invention.

Claims

1. A method for detecting temperature and voltage signals based on a multi-channel IGBT module, characterized in that: Includes the following steps: Step 1: Integrate a high-precision reference voltage source on each IGBT module, and control the high-precision reference voltage source to simultaneously provide a voltage of the same value to each corresponding IGBT module. Step 2: Connect the high-precision voltage divider circuit between the high-precision reference voltage source and ground. The intermediate node of the high-precision voltage divider circuit generates a raw voltage signal that varies with temperature based on the DC voltage value input from the high-precision reference voltage source. Step 3: Connect the original voltage signal of the high-precision voltage divider circuit to the non-inverting input of multiple rectifier circuits, and connect the final output of multiple rectifier circuits to the common output node of each IGBT module. Step 4: By comparing the temperature and voltage signals at the final output terminals of multiple rectifier circuits, the maximum temperature and voltage signal is output.

2. The temperature and voltage signal detection method based on a multi-channel IGBT module according to claim 1, characterized in that: In step 1, the voltage is a DC voltage.

3. The temperature and voltage signal detection method based on a multi-channel IGBT module according to claim 1, characterized in that: In step 2, the high-precision voltage divider circuit includes a fixed resistor and an NTC thermistor; One end of the fixed resistor is connected to a high-precision reference voltage source, and the other end is connected to ground through an NTC thermistor; The junction between the fixed resistor and the NTC thermistor is connected to the input terminal of the rectifier circuit.

4. The temperature and voltage signal detection method based on a multi-channel IGBT module according to claim 3, characterized in that: In step 3, the rectifier circuit includes an operational amplifier and a feedback diode. The non-inverting input of the operational amplifier is connected to the junction between the fixed resistor and the NTC thermistor. The output of the operational amplifier is connected to the final output of the IGBT module through the feedback diode, and is also connected to the inverting input through the feedback path.

5. The temperature and voltage signal detection method based on a multi-channel IGBT module according to claim 1, characterized in that: Step 4 is followed by: Step 51: Connect an MCU microcontroller and an IGBT junction temperature observer to each IGBT module. Step 52: The IGBT junction temperature observer of the IGBT module that outputs the maximum value temperature voltage signal detects the temperature voltage signal of the IGBT module that outputs the maximum value temperature voltage signal in real time. Step 53: The IGBT junction temperature observer of the IGBT module with the non-maximum output temperature voltage signal performs intermittent sampling inspection of the temperature voltage signal of the IGBT module with the non-maximum output temperature voltage signal. Step 54: The MCU microcontroller records the maximum temperature and voltage signal value of each IGBT module during the sampling period in real time based on the intermittent sampling inspection records, and compares it with the maximum temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal during the corresponding sampling period. Step 55: The MCU microcontroller records the average temperature and voltage signal value of each IGBT module during the sampling period in real time based on the intermittent sampling inspection records, and compares it with the minimum temperature and voltage signal of the IGBT module with the maximum output temperature and voltage signal during the corresponding sampling period. Step 56: The MCU microcontroller calculates the difference between the temperature and voltage signal with the maximum output value and the temperature and voltage signal with the maximum output value during sampling, and obtains the difference deviation rate. Step 57: The MCU microcontroller compares the temperature and voltage signal with the maximum output value with the minimum temperature and voltage signal with the non-maximum output value during sampling and the average temperature and voltage signal value of the IGBT module during the sampling period to calculate the rate of change of the difference. Step 58: The ratio of the temperature voltage signal with the maximum output value of the IGBT module is obtained by using the formula: difference change rate / difference deviation rate.

6. The temperature and voltage signal detection method based on a multi-channel IGBT module according to claim 5, characterized in that: The process further includes the following after step 58: Step 61: The MCU microcontroller sorts the real-time temperature and voltage signal values ​​of all IGBT modules sampled at the same time. Step 62: When the real-time temperature difference between the IGBT module with the non-maximum output temperature voltage signal and the IGBT module with the maximum output temperature voltage signal reaches the set warning detection value, the IGBT module with the maximum output temperature voltage signal will be randomly sampled again between adjacent standard sampling times. Step 63: When the real-time temperature difference between the IGBT module with the non-maximum output temperature voltage signal and the IGBT module with the maximum output temperature voltage signal reaches the set alarm detection value, the load change of the IGBT module and its temperature voltage signal are monitored in real time.

7. The temperature and voltage signal detection method based on a multi-channel IGBT module according to claim 6, characterized in that: In step 63, the MCU microcontroller monitors in real time the number of loads of IGBT modules corresponding to the temperature and voltage signal values ​​close to the final output terminal, as well as their corresponding power protection and temperature and voltage signal changes, and monitors in real time the number of loads of IGBT modules corresponding to the temperature and voltage signal with the maximum output value, as well as their corresponding power protection and temperature and voltage signal changes.

8. The temperature and voltage signal detection method based on a multi-channel IGBT module according to claim 7, characterized in that: The process after step 63 also includes: When a new load is needed, the MCU microcontroller identifies the quantity and power of the load, and based on the temperature and voltage signals at the final output terminals of multiple rectifier circuits, recommends that the load be installed sequentially on the IGBT module with the largest difference between the temperature and voltage signals at the final output terminals of the multiple rectifier circuits.

9. The temperature and voltage signal detection method based on a multi-channel IGBT module according to claim 8, characterized in that: The MCU microcontroller is equipped with a wireless communicator.

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