Performance testing device for freewheeling diode

Abstract

The present application relates to a performance detection device for a freewheeling diode. The performance detection device includes a power supply, a rectifier transistor, a parallel branch, a freewheeling diode to be detected, a processing circuit, and a load circuit; the power supply forms a first path between the transistor and the load circuit, which is used to supply power to the load circuit when the transistor is turned on, so as to generate an excitation current through the first path; the parallel branch is connected in parallel with the freewheeling diode to be detected, which is used to shunt the excitation current; the processing circuit is used to obtain the shunting result and determine the performance parameters of the freewheeling diode to be detected according to the shunting result. The performance of the freewheeling diode can be detected by using this device.

Description

Technical Field

[0001] The present application relates to the field of nuclear power technology, and in particular to a performance detection device for a freewheeling diode. Background Art

[0002] The quality of the nuclear power plant emergency diesel generator is the last line of defense for the safety of the entire nuclear power plant power supply. The nuclear power plant emergency diesel generator generates excitation voltage through its excitation system to enable the nuclear power plant emergency diesel generator to operate normally, thereby ensuring the safe shutdown of the units in the nuclear power plant.

[0003] The main function of the excitation system of the emergency diesel generator of a nuclear power plant is the excitation regulator, and the chopper power module is the power execution unit of the excitation regulator, that is, the chopper power module is the core of the excitation regulator. The freewheeling diode in the chopper power module has the risk of overcurrent burning, which leads to the problem of excitation system failure of the emergency diesel generator of the nuclear power plant, reducing the safety of the nuclear power plant.

[0004] There has been no systematic research on freewheeling diodes so far. Therefore, how to avoid the risk of freewheeling diodes in chopper power modules burning out due to overcurrent, which may lead to excitation system failure of emergency diesel generators in nuclear power plants, has become a key research topic for researchers in this field. Summary of the invention

[0005] Based on this, it is necessary to provide a freewheeling diode performance detection device capable of detecting the performance of the freewheeling diode in order to solve the above technical problems. The performance detection device includes a power supply, a rectifier transistor, a parallel branch, a freewheeling diode to be detected, a processing circuit and a load circuit;

[0006] The power supply forms a first path between the rectifier transistor and the load circuit, and is used to supply power to the load circuit when the rectifier transistor is turned on, so as to generate an excitation current through the first path;

[0007] The parallel branch is connected in parallel with the freewheeling diode to be detected, and is used to shunt the excitation current;

[0008] The processing circuit is used to obtain the shunting result and determine the performance parameter of the freewheeling diode to be detected according to the shunting result.

[0009] In one embodiment, the parallel branch includes a first diode, a first end of the first diode and a first end of the freewheeling diode to be detected are connected to the source of the rectifier transistor and the first end of the load circuit, and a second end of the first diode and a second end of the freewheeling diode to be detected are connected to the second end of the power supply and the second end of the load circuit.

[0010] In one embodiment, the processing circuit includes a detection module and a processing module;

[0011] The detection module is used to obtain the diversion result and send the diversion result to the processing module;

[0012] The processing module is used to determine the performance parameter according to the diversion result.

[0013] In one embodiment, the shunting result includes at least one parameter of the current shared by the freewheeling diode to be detected and the current ratio shared by the freewheeling diode to be detected, and the current ratio shared by the freewheeling diode to be detected is the ratio of the current shared by the freewheeling diode to be detected to the excitation current.

[0014] In one of the embodiments, the performance detection device further includes a first temperature sensor;

[0015] The first temperature sensor is used to detect a first temperature value of the freewheeling diode to be detected, and send the first temperature value to the processing circuit;

[0016] The processing circuit is used to determine the performance parameter of the freewheeling diode to be detected according to the first temperature value and the shunting result.

[0017] In one of the embodiments, the performance detection device further includes a second temperature sensor;

[0018] The second temperature sensor is used to detect a second temperature value of the environment in which the freewheeling diode to be detected is located, and send the second temperature value to the processing circuit;

[0019] The processing circuit is used to determine the performance parameter of the freewheeling diode to be detected according to the first temperature value, the second temperature value and the shunting result.

[0020] In one of the embodiments, the detection module is further used to obtain the minimum forward conduction voltage drop of the freewheeling diode to be detected;

[0021] The processing circuit is also used to determine the performance parameters of the freewheeling diode to be detected based on the first temperature value, the second temperature value, the shunting result and the minimum forward conduction voltage drop of the freewheeling diode to be detected.

[0022] In one embodiment, the processing module is further used to determine, based on the performance parameters under different excitation currents, how the performance parameters of the freewheeling diode to be detected change with different excitation currents.

[0023] In one embodiment, the processing circuit is used to determine a target freewheeling diode from among the multiple different types of freewheeling diodes to be detected according to performance parameters of the multiple different types of freewheeling diodes to be detected.

[0024] In one embodiment, the processing circuit is used to determine a first multiple relationship between a minimum forward conduction voltage drop and a target voltage drop of each type of freewheeling diode to be detected according to performance parameters of the plurality of different types of freewheeling diodes to be detected, wherein the first multiple relationship is used to characterize that the minimum forward conduction voltage drop is equal to N times the target voltage drop, where N is a value greater than 1, and the target voltage drop is the voltage drop when the temperature of the freewheeling diode to be detected exceeds a preset temperature threshold and is damaged;

[0025] The processing circuit is also used to determine the target freewheeling diode from the freewheeling diodes to be detected of the model according to the first multiple relationship.

[0026] The performance detection device for the freewheeling diode includes a power supply, a rectifier transistor, a parallel branch, a freewheeling diode to be detected, a processing circuit and a load circuit. The power supply forms a first path between the rectifier transistor and the load circuit, and is used to supply power to the load circuit when the rectifier transistor is turned on, so as to generate an excitation current through the first path. The parallel branch and the freewheeling diode to be detected are connected in parallel, and are used to shunt the excitation current. The processing circuit is used to obtain the shunting result and determine the performance parameters of the freewheeling diode to be detected based on the shunting result. Since the power supply forms a first path between the rectifier transistor and the load circuit, the first path is used to supply power to the load circuit when the rectifier transistor is turned on, so as to generate an excitation current by the first path, and the parallel branch is connected in parallel with the freewheeling diode to be detected, so as to shunt the excitation current. Therefore, the performance detection device of the freewheeling diode provided by the present application is the same as the working principle of the chopper power module in the excitation system of the emergency diesel generator of the actual nuclear power plant. Therefore, the performance parameters of the freewheeling diode to be detected determined by the processing circuit according to the shunting result also meet the actual operation requirements of the chopper power module, so that the present application can complete the performance detection of the freewheeling diode to be detected. Furthermore, the freewheeling diode is selected according to the performance parameters of the freewheeling diode to be detected, that is, the freewheeling diode is selected in advance according to the operation requirements of the emergency diesel generator of the actual nuclear power plant, which can avoid the overcurrent burning of the freewheeling diode in the chopper power module caused by the lack of systematic research on the freewheeling diode, thereby solving the problem of the excitation system failure of the emergency diesel generator of the nuclear power plant due to the risk of overcurrent burning of the freewheeling diode, and improving the safety of the nuclear power plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is the working principle diagram of the chopper power module;

[0028] Figure 2 This is a structural block diagram of a performance detection device for a freewheeling diode in an embodiment of the present application;

[0029] Figure 3 This is a circuit diagram of a performance detection device for a freewheeling diode in an embodiment of the present application;

[0030] Figure 4 This is a schematic diagram of the structure of the processing circuit in the embodiment of the present application;

[0031] Figure 5 A circuit diagram of another device for detecting the performance of a freewheeling diode in an embodiment of the present application;

[0032] Figure 6 This is a diagram of the internal structure of a computer device in an embodiment of the present application.

[0033] Description of reference numerals:

[0034] 101-diode, 102-diode, 103-diode, 104-diode, 105-diode, 106-diode 106, 107-filter capacitor. 108-diode, 109-diode, 110-diode, 111-transistor, 112-transistor, 113-freewheeling diode, 114-three-phase power supply of auxiliary exciter, 115-generator rotor winding, 200 performance detection device, 201-power supply, 202-rectifier transistor, 203-parallel branch, 204-freewheeling diode to be detected, 205-load circuit, 206-processing circuit, 301-power supply, 302-rectifier transistor, 303-first diode, 304-freewheeling diode to be detected, 305-load circuit, 400-processing circuit, 401-detection module, 402-processing module, 501-power supply, 502-rectifier transistor, 503-first diode, 504-freewheeling diode to be detected, 505-load circuit, 506-detection module, 507-processing module. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0036] The excitation system of the emergency diesel generator of a nuclear power plant is a "three-machine excitation" system, which includes a diesel generator, a main exciter and an auxiliary exciter, and the excitation regulator is set between the main exciter and the auxiliary exciter. The excitation system of the emergency diesel generator of a nuclear power plant includes two channels, A and B. Channel A and channel B are backup for each other. When there is a problem with the operation of channel A, it will switch to channel B in time.

[0037] Figure 1The working principle diagram of the chopper power module is shown in Figure 2. The chopper power module is the power execution unit of the excitation regulator, and its main function is to rectify the AC power input from the auxiliary exciter into DC. It can be understood that the chopper power module in the A channel of the excitation regulator and the chopper power module in the B channel have exactly the same structure.

[0038] Specifically, Figure 1 As shown, the chopper power module includes diodes 101 to 106 , a filter capacitor 107 , diodes 108 to 110 , a transistor 111 , a transistor 112 , a diode 113 , an auxiliary exciter three-phase power supply 114 and a generator rotor winding 115 .

[0039] The auxiliary exciter three-phase power supply 114 is coaxially arranged with the rotor of the generator. When the rotor of the generator rotates, the auxiliary exciter three-phase power supply 114 starts to work and supplies power to the chopper power module. Diodes 101 to 106 can be understood as three pairs of rectifier diodes, which are used to rectify the AC of the auxiliary exciter three-phase power supply 114 into DC by periodically conducting two by two. For example, in the first cycle, diodes 101 and diodes 106 are turned on, and in the second cycle, diodes 101 and diodes 104 are turned on. Filter capacitor 107 is used to filter the voltage waveform after rectification by diodes 101 to 106. Diode 108 can be understood as a protection diode to prevent the chopper power module from working in reverse.

[0040] Transistor 111 and transistor 112 are two insulated gate bipolar transistors (IGBT) with exactly the same parameters and structures. Both transistor 111 and transistor 112 receive a pulse signal from a common gateway interface (CGI) pulse trigger unit of a control circuit to control the on and off of transistor 111 and transistor 112. For example, when the CGI pulse trigger unit signal sends a pulse signal, transistor 111 and transistor 112 are turned on, so that the chopping power module generates an excitation voltage and an excitation current. Specifically, the control circuit can adjust the duty cycle of the pulse signal of the pulse trigger unit to control the on time of transistor 111 and transistor 112.

[0041] Diodes 109 and 110 play a freewheeling role in a fixed channel. For example, diodes 109 and 110 play a freewheeling role when channel A is working. In other words, diodes 109 and 110 are used to maintain the freewheeling of the entire chopper power module during the commutation interruption period of the rectification of diodes 101 to 106. Diode 113 plays a freewheeling role during the interruption period when channels A and B are switched. It can be understood that although diodes 109, 110 and 113 are all semiconductor components that play a role in maintaining the continuity of the loop current, diodes 109, 110 and 113 play a freewheeling role in different working stages or ranges of the excitation system.

[0042] Finally, the chopper power module generates an excitation voltage and an excitation current for the generator rotor winding 115 to work.

[0043] Under normal circumstances, when the transistor 112 is in the rectifier commutation freewheeling operation, the diode 113 for freewheeling during channel switching should not work, that is, the diode 113 should not have current. However, the performance parameters of the diode 113 used for freewheeling during channel switching, such as the forward conduction voltage, are very similar to the performance parameters of the transistor 112 used for rectification and commutation, and the diode 113 and the transistor 112 are in parallel in structure. Therefore, when the transistor 112 is working normally, the diode 113 actually also assumes the role of partial shunting. In other words, the diode 113 assumes the freewheeling role that it should not assume during the commutation period of the rectification of the diodes 101 to 106. Since the diode 113 has long assumed the partial shunting during the commutation period of the rectification of the diodes 101 to 106, there will be a heat accumulation effect in the diode 113 under continuous operation, and then the diode 113 exceeds the maximum temperature that it can withstand, causing overcurrent burning.

[0044] Furthermore, when the diode 113 is damaged and causes a metallic direct short circuit in the DC side loop, the short circuit current flowing through the transistor 112 reaches hundreds of amperes or even thousands of amperes, which exceeds the maximum current that the transistor 112 can withstand. Therefore, the transistor 112 is also damaged.

[0045] Ultimately, the overcurrent burning of the freewheeling diode in the chopper power module caused the excitation system of the nuclear power plant's emergency diesel generator to malfunction, reducing the safety of the nuclear power plant.

[0046] At present, there has been no systematic research on the freewheeling diode. The type and performance of the freewheeling diode in the chopper power module of the excitation system of the emergency diesel generator of the nuclear power plant are often selected based on conventional production experience, the guidance of the freewheeling diode manufacturer or the technical specifications of the freewheeling diode. The performance of the freewheeling diode can only be verified after the emergency diesel generator of the nuclear power plant is started. In other words, it is currently impossible to select the type and performance of the freewheeling diode in advance according to the actual operation requirements of the emergency diesel generator of the nuclear power plant. When the problem of the excitation system of the emergency diesel generator of the nuclear power plant finally occurs due to the overcurrent burning of the diode 113 in the chopper power module, it is generally only replaced with the same type of freewheeling diode, and safety accidents still exist.

[0047] Based on this, it is necessary to provide a performance detection device for a freewheeling diode that can detect the performance of the freewheeling diode in order to solve the above technical problems.

[0048] Figure 2 : is a structural block diagram of the performance detection device of the freewheeling diode in the embodiment of the present application. Figure 2 As shown, the performance detection device 200 includes a power supply 201 , a rectifier transistor 202 , a parallel branch 203 , a freewheeling diode 204 to be detected, a load circuit 205 and a processing circuit 206 .

[0049] The power supply 201 forms a first path between the rectifying transistor 202 and the load circuit 205 , and is used to supply power to the load circuit 205 when the rectifying transistor 202 is turned on, so as to generate an excitation current through the first path.

[0050] The parallel branch 203 and the to-be-detected freewheeling diode 204 are connected in parallel to shunt the excitation current.

[0051] The processing circuit 205 is used to obtain the shunting result and determine the performance parameters of the freewheeling diode 204 to be tested according to the shunting result.

[0052] In this embodiment, the processing module may be a computer device, which may include a central processing unit (CPU), a digital signal processor (DSP), a field programmable gate array (FPGA) or other programmable logic devices. The performance detection device 200 is a device determined according to the actual circuit to which the freewheeling diode 204 to be detected needs to be subsequently connected, and is used to detect the freewheeling diode 204 to be detected before the freewheeling diode 204 to be detected is formally connected to the chopper power module in the excitation system of the emergency diesel generator of the nuclear power plant, so as to determine the performance parameters of the freewheeling diode 204 to be detected.

[0053] Specifically, combined Figure 1 and Figure 2 , the performance detection device 200 can be understood as Figure 1 An equivalent circuit of a chopper power module in the excitation system of an emergency diesel generator of a nuclear power plant in practice. In this embodiment, the diode 113 in the actual circuit is equivalent to the freewheeling diode 204 to be detected in the performance detection device 200, the transistor 111 and the transistor 112 in the actual circuit where the freewheeling diode 204 to be detected is located are equivalent to the rectifier transistor 202 of the performance detection device 200, the diode 109 and the diode 110 in the actual circuit where the freewheeling diode 204 to be detected is located are equivalent to the parallel branch 203 of the performance detection device 200, and the generator rotor winding 115 in the actual circuit where the freewheeling diode 204 to be detected is located is equivalent to the load circuit 205 of the performance detection device 200.

[0054] That is to say, the performance detection device 200 simulates the actual chopper power module of the freewheeling diode 204 to be detected. Therefore, in the performance detection device 200 of the present application, like the actual chopper power module circuit, the power supply 201 can form a first path between the rectifier transistor 202 and the load circuit 205, and the first path is used to supply power to the load circuit 205 when the rectifier transistor 202 is turned on, so as to generate a simulated excitation current by forming the first path between the rectifier transistor 202 and the load circuit 205. The parallel branch 203 and the freewheeling diode 204 to be detected are connected in parallel, and the excitation current is shunted. That is, a part of the excitation current simulated in the performance detection device 200 is provided by the current flowing through the freewheeling diode 204 to be detected, and a part is provided by the current flowing through the parallel branch 203.

[0055] Furthermore, the processing circuit 205 in the performance detection device 200 is used to obtain the shunting result, and finally determine the performance parameter of the freewheeling diode 204 to be detected according to the shunting result. The shunting result may be the current actually flowing through the freewheeling diode 204 to be detected.

[0056] Among them, the performance parameter can be the change of the shunting result of the freewheeling diode to be tested with the excitation current under different working conditions, or the change of the temperature rise of the freewheeling diode to be tested with the excitation current under different working conditions, etc., which is not limited in this embodiment.

[0057] For example, the processing circuit 205 in the performance detection device can determine the performance parameters of the freewheeling diode 204 to be detected according to the shunting results of the freewheeling diodes 204 of different models to be detected under different excitation currents. For example, the performance parameters of the freewheeling diode 204 to be detected are used to characterize the change of the shunting results of the freewheeling diode 204 to be detected with the excitation current. Finally, the processing circuit 205 can determine the freewheeling diode X with the smallest shunting result under each excitation current according to the determined performance parameters of the freewheeling diodes of different models, so as to use the freewheeling diode X as the freewheeling diode of the chopper power module in the excitation system of the emergency diesel generator of the actual nuclear power plant, so as to avoid the freewheeling diode X from being burned due to overcurrent, thereby improving the safety of the nuclear power plant.

[0058] The performance detection device of the freewheeling diode provided in this embodiment includes a power supply, a transistor, a parallel branch, a freewheeling diode to be detected, a processing circuit and a load circuit, wherein the power supply forms a first path between the transistor and the load circuit, which is used to supply power to the load circuit when the transistor is turned on, so as to generate an excitation current by the first path, the parallel branch is connected in parallel with the freewheeling diode to be detected, and is used to shunt the excitation current, and the processing circuit is used to obtain the shunting result, and determine the performance parameters of the freewheeling diode to be detected according to the shunting result. Since the power supply forms a first path between the rectifier transistor and the load circuit, the first path is used to supply power to the load circuit when the rectifier transistor is turned on, so as to generate an excitation current by the first path, and the parallel branch is connected in parallel with the freewheeling diode to be detected, and is used to shunt the excitation current, therefore, the performance detection device of the freewheeling diode provided in this application is the same as the working principle of the chopper power module in the excitation system of the emergency diesel generator of the actual nuclear power plant, therefore, the performance parameters of the freewheeling diode to be detected determined by the processing circuit according to the shunting result also meet the actual operation requirements of the chopper power module, so that this application can complete the performance detection of the freewheeling diode to be detected. Furthermore, the freewheeling diode is selected according to the performance parameters of the freewheeling diode to be tested, that is, the freewheeling diode is selected in advance according to the actual operating requirements of the nuclear power plant emergency diesel generator. This can avoid the overcurrent burning of the freewheeling diode in the chopper power module caused by the lack of systematic research on the freewheeling diode. This solves the problem of the excitation system failure of the nuclear power plant emergency diesel generator caused by the risk of overcurrent burning of the freewheeling diode, thereby improving the safety of the nuclear power plant.

[0059] Figure 3 Schematic diagram of the circuit of the performance detection device of the freewheeling diode in the embodiment of the present application. Figure 3 As shown, optionally, the parallel branch includes a first diode 303, a first end of the first diode 303 and a first end of the freewheeling diode 304 to be detected are respectively connected to the source of the rectifier transistor 302 and the first end of the load circuit 305, and a second end of the first diode 303 and a second end of the freewheeling diode 304 to be detected are respectively connected to the second end of the power supply 301 and the second end of the load circuit 305.

[0060] In this embodiment, the circuit diagram of the performance detection device is as follows: Figure 3 As shown, combined Figure 1 , the rectifier transistor 302 simulates the Figure 1 The transistors 111 and 112 in FIG. 1 are also applicable to insulated gate bipolar transistors. The first diode 303 simulates Figure 1 The diode 110 in the embodiment and the freewheeling diode 304 to be tested simulate the Figure 1 The diode 113 in the load circuit 305 simulates Figure 1 The generator rotor winding 115 in.

[0061] Specifically, in this embodiment, a performance detection device for a freewheeling diode can be built in the excitation sample cabinet. The rectifier transistor 302 is the transistor 111 and the transistor 112 in the excitation sample cabinet, the first diode 303 is the diode 110 corresponding to the rectifier transistor 302, and the freewheeling diode 304 to be detected is the diode 113 in the excitation sample cabinet. The output of the excitation cabinet is connected to a simulated rotor load, that is, a load circuit 305. The load circuit 305 simulates the rotor winding 115 of the generator, which is composed of an inductor and a resistor in series.

[0062] Please continue to refer to Figure 3 , I1 is the current of the first diode 303, I2 is the current flowing through the freewheeling diode 304 to be detected, Ie is the current flowing through the load circuit 305, and Ie is the total excitation current of the generator rotor winding. When the performance detection device is working, since the first diode 303 and the freewheeling diode 304 to be detected share the freewheeling current, during freewheeling, Ie=I1+I2.

[0063] In this embodiment, the parallel branch includes a first diode, the first end of the first diode and the first end of the freewheeling diode to be detected are connected to the source of the transistor and the first end of the load circuit, and the second end of the first diode and the second end of the freewheeling diode to be detected are connected to the second end of the power supply and the second end of the load circuit. Therefore, the parallel branch and the freewheeling diode to be detected are connected in parallel to shunt the excitation current, and the shunt result finally obtained by the processing circuit can also meet the actual chopper power module, thereby completing the detection of the performance of the freewheeling diode.

[0064] Figure 4 is a schematic diagram of the structure of the processing circuit in the embodiment of the present application, such as Figure 4 As shown, optionally, the processing circuit 400 includes a detection module 401 and a processing module 402 .

[0065] The detection module 401 is used to obtain the diversion result and send the diversion result to the processing module.

[0066] The processing module 402 is used to determine the performance parameter according to the diversion result.

[0067] In this embodiment, the detection module 401 is used to obtain the shunting result and send the shunting result to the processing module. The detection module 401 can be an ammeter, a multimeter, an oscilloscope, etc., which is not limited in this embodiment. Figure 5 , Figure 5 FIG. 1 is a circuit diagram of another device for detecting the performance of a freewheeling diode in an embodiment of the present application. Figure 5As shown, the detection module 506 obtains the shunting result at every preset time period, and sends the shunting result to the processing module 507 in real time or regularly. Among them, the detection module 506 can obtain the current I2 flowing through the freewheeling diode 504 to be detected and the excitation current Ie flowing through the load circuit at every preset time period. Of course, the detection module 506 can further obtain the current I1 flowing through the rectifier transistor 502 and the first diode 503 at every preset time period. Specifically, in this embodiment, an oscilloscope is used to obtain the excitation current Ie and the current I2.

[0068] After the processing module 507 obtains the shunting result sent by the detection module 506, it can further analyze the shunting result to determine the performance parameters of the freewheeling diode 504 to be detected. For example, the performance parameters of the freewheeling diode 504 include the changes in the shunting result of the freewheeling diode 504 with different excitation currents.

[0069] In this embodiment, the processing circuit includes a detection module and a processing module. The detection module is used to obtain the shunting result and send the shunting result to the processing module. The processing module is used to determine the performance parameters according to the shunting result. Then, the processing circuit can be used to obtain the shunting result, and determine the performance parameters of the freewheeling diode to be detected according to the shunting result, so as to complete the performance detection of the freewheeling diode to be detected.

[0070] Optionally, the shunting result includes at least one parameter of the current shared by the freewheeling diode to be detected and the current proportion shared by the freewheeling diode to be detected, and the current proportion shared by the freewheeling diode to be detected is the ratio of the current shared by the freewheeling diode to be detected to the excitation current.

[0071] In this embodiment, the magnitude of the generated excitation current Ie can be changed by adjusting the magnitude of the power supply 501 or the load circuit 505. Generally, in order to be closer to the actual working condition of the emergency diesel generator of a nuclear power plant, the power supply 501 adopts a DC current source, thereby directly adjusting the magnitude of the excitation current Ie.

[0072] Combination Figure 5 , the shunting result includes the current I2 shared by the freewheeling diode 504 to be tested and / or the current proportion I2 / Ie shared by the freewheeling diode 504 to be tested. Specifically, the shunting result may be shown in the following Table 1. It is understandable that Table 1 takes a certain type of freewheeling diode to be tested as an example, and the shunting result may also include the results of various types of freewheeling diodes to be tested.

[0073] Table 1 Schematic diagram of diversion results

[0074]

[0075] In this embodiment, the shunting result includes at least one parameter of the current shared by the freewheeling diode to be detected and the current proportion shared by the freewheeling diode to be detected. The current proportion shared by the freewheeling diode to be detected is the ratio of the current shared by the freewheeling diode to be detected to the excitation current. Then, the processing circuit can determine the performance parameters of the freewheeling diode to be detected based on the shunting result, thereby improving the safety of the nuclear power plant.

[0076] Optionally, the performance detection device also includes a first temperature sensor.

[0077] The first temperature sensor is used to detect a first temperature value of the freewheeling diode to be detected and send the first temperature value to the processing circuit.

[0078] The processing circuit is used to determine the performance parameters of the freewheeling diode to be detected according to the first temperature value and the shunting result.

[0079] In this embodiment, the first temperature sensor may be a diode temperature sensor, an infrared temperature measuring gun, etc., which is not limited in this embodiment. The processing circuit is connected to the first temperature sensor signal, and the first temperature sensor obtains the first temperature value of the freewheeling diode to be detected every preset time period and sends the first temperature value to the processing circuit. Furthermore, after the processing circuit obtains the first temperature value, it can determine the performance parameters of the freewheeling diode to be detected based on the first temperature value and the shunting result. The first temperature value may be as shown in Table 2 below.

[0080] An optional way to determine the performance parameters of the freewheeling diode to be detected is that the processing circuit receives the first temperature value of the freewheeling diode to be detected at different times, and then the processing circuit can calculate the temperature rise of the freewheeling diode to be detected, so that the processing circuit determines the performance parameters of the freewheeling diode to be detected based on the first temperature value and the shunting result. The performance parameters of the freewheeling diode to be detected may include a freewheeling diode with a smaller shunting result and a smaller temperature rise change under each excitation current. It can be understood that the temperature rise of the first temperature value is also the temperature rise of the freewheeling diode to be detected. Table 2 takes a certain model of the freewheeling diode to be detected as an example, and the first temperature value may also include the first temperature values ​​of various models of freewheeling diodes to be detected.

[0081] Table 2 First temperature value

[0082]

[0083] In this embodiment, the performance detection device also includes a first temperature sensor, which is used to detect a first temperature value of the freewheeling diode to be detected and send the first temperature value to a processing circuit. The processing circuit is used to determine the performance parameters of the freewheeling diode to be detected based on the first temperature value and the shunting result. Since the performance parameters of the freewheeling diode to be detected can be determined based on the first temperature value and the shunting result, the performance parameters of the freewheeling diode to be detected that are finally determined are relatively accurate and meet actual needs.

[0084] Optionally, the performance detection device further includes a second temperature sensor;

[0085] The second temperature sensor is used to detect a second temperature value of the environment in which the freewheeling diode to be detected is located, and send the second temperature value to the processing circuit.

[0086] The processing circuit is used to determine the performance parameters of the freewheeling diode to be detected according to the first temperature value, the second temperature value and the shunting result.

[0087] In this embodiment, the second temperature sensor may be an ambient thermometer, the processing circuit is connected to the second temperature sensor signal, the second temperature sensor obtains the second temperature value of the environment in which the freewheeling diode to be detected is located at a preset time period, and sends the second temperature value to the processing circuit. Further, after the processing circuit obtains the second temperature value, it can determine the performance parameters of the freewheeling diode to be detected according to the first temperature value, the second temperature value and the shunting result.

[0088] One way to achieve this is that the processing circuit obtains the shunting results, the first temperature value and the second temperature value of each model under the same excitation current, as shown in Table 3 below, so that the processing circuit determines the performance parameters of the freewheeling diode to be detected. The performance parameters of the freewheeling diode to be detected may include the first temperature values ​​of the freewheeling diodes to be detected of each model under the same second ambient temperature value and the same excitation current.

[0089] Generally, it is difficult for the second ambient temperature value to be exactly the same. Therefore, in a specific embodiment, the processing circuit subtracts the second temperature value from the first temperature value, and determines the actual temperature rise of the freewheeling diode to be tested based on the result of subtracting the second temperature value from the first temperature value to avoid the influence of the second temperature value on the result.

[0090] Table 3 Schematic diagram of the first temperature value, the second temperature value and the diversion result

[0091]

[0092]

[0093] In this embodiment, the performance detection device also includes a second temperature sensor, which is used to detect a second temperature value of the environment in which the freewheeling diode to be detected is located, and send the second temperature value to the processing circuit. The processing circuit is used to determine the performance parameters of the freewheeling diode to be detected based on the first temperature value, the second temperature value and the shunting result. Since the performance parameters of the freewheeling diode to be detected can be determined based on the first temperature value, the second temperature value and the shunting result, the accuracy of the determined performance parameters of the freewheeling diode to be detected is improved.

[0094] Optionally, the detection module is also used to obtain the minimum forward conduction voltage drop of the freewheeling diode to be detected; the processing circuit is also used to determine the performance parameters of the freewheeling diode to be detected based on the first temperature value, the second temperature value, the shunting result and the minimum forward conduction voltage drop of the freewheeling diode to be detected.

[0095] In this embodiment, the detection module may further include a multimeter or a voltmeter for obtaining the minimum forward conduction voltage drop of the freewheeling diode to be detected, where the minimum forward conduction voltage drop represents the lowest forward voltage at which the freewheeling diode to be detected can be turned on.

[0096] Further, the processing circuit determines the performance parameter of the freewheeling diode to be detected according to the first temperature value, the second temperature value, the shunting result, and the minimum forward conduction voltage drop of the freewheeling diode to be detected. For example, the processing circuit determines that the greater the minimum forward conduction voltage drop of the freewheeling diode to be detected, the smaller the proportion of the current shared by the shunting is.

[0097] In this embodiment, the detection module is also used to obtain the minimum forward conduction voltage drop of the freewheeling diode to be detected; the processing circuit is also used to determine the performance parameters of the freewheeling diode to be detected according to the first temperature value, the second temperature value, the shunting result and the minimum forward conduction voltage drop of the freewheeling diode to be detected. Since the performance parameters of the freewheeling diode to be detected can also be determined according to the minimum forward conduction voltage drop of the freewheeling diode to be detected in the present application, the accuracy of the performance parameters of the freewheeling diode to be detected is further improved.

[0098] Optionally, the processing module is further used to determine, based on the performance parameters under different excitation currents, how the performance parameters of the freewheeling diode to be detected change with different excitation currents.

[0099] In this embodiment, the performance parameters may include the temperature rise of the first temperature value of the freewheeling diode to be detected and the current share of the freewheeling diode to be detected. The processing module can determine the change of the performance parameters of the freewheeling diode to be detected with different excitation currents according to the performance parameters under different excitation currents, for example, determine the change curve of the temperature rise of the first temperature value of the freewheeling diode to be detected with different excitation currents. It can be understood that different excitation currents are used to represent different operating conditions of the excitation system of the emergency diesel generator of the nuclear power plant.

[0100] For example, the processing module determines, based on the performance parameters of the freewheeling diode to be detected, that changes in the excitation current for different performance parameters of the freewheeling diode to be detected may be: the larger the excitation current, the higher the current proportion shared by the freewheeling diode to be detected, the temperature rise of the first temperature value is proportional to the excitation current, the larger the excitation current, the higher the temperature rise of the first temperature value, different types of freewheeling diodes have different performance parameters, the minimum forward conduction voltage drop is inversely proportional to the excitation current, the larger the minimum forward conduction voltage drop of the freewheeling diode to be detected, the smaller the current proportion shared by the freewheeling diode to be detected, and so on.

[0101] The processing module in this embodiment is also used to determine how the performance parameters of the freewheeling diode to be detected change with different excitation currents based on the performance parameters under different excitation currents, thereby selecting the freewheeling diode according to how the performance parameters of the freewheeling diode to be detected change with different excitation currents, thereby solving the problem of the excitation system failure of the nuclear power plant emergency diesel generator caused by the risk of the freewheeling diode burning due to overcurrent, thereby improving the safety of the nuclear power plant.

[0102] Optionally, the processing circuit is used to determine a target freewheeling diode from a plurality of different types of freewheeling diodes to be detected based on performance parameters of the plurality of different types of freewheeling diodes to be detected.

[0103] In this embodiment, the processing circuit can determine the target freewheeling diode from the freewheeling diodes of multiple different models to be detected according to the performance parameters of the freewheeling diodes of multiple different models to be detected. One way to achieve this is that the processing circuit obtains the performance parameters of the freewheeling diodes of multiple different models to be detected, and determines the freewheeling diode with the smallest temperature rise change of the first temperature value from the freewheeling diodes of multiple different models to be detected as the target freewheeling diode, and then the target freewheeling diode is used as the freewheeling diode of the chopper power module in the excitation system of the emergency diesel generator of the actual nuclear power plant. Since the freewheeling diode with the smallest temperature rise change of the first temperature value is determined as the target freewheeling diode, the phenomenon of overcurrent burning of the freewheeling diode can be avoided, thereby improving the safety of the nuclear power plant. Of course, the processing circuit can also determine the target freewheeling diode in other ways, such as multiplying the temperature rise of the first temperature value and the current share by a preset weight coefficient, respectively, to obtain a freewheeling diode with a smaller temperature rise and a smaller current share of the first temperature value as the target freewheeling diode, which is not limited in this embodiment.

[0104] The processing circuit in the present embodiment is used to determine a target freewheeling diode from a plurality of different types of freewheeling diodes to be detected according to the performance parameters of the freewheeling diodes to be detected. Since the freewheeling diode is selected according to the performance parameters of the freewheeling diode to be detected, the freewheeling diode can be selected in advance according to the actual operating requirements of the nuclear power plant emergency diesel generator. The risk of overcurrent burning of the freewheeling diode in the chopper power module caused by the lack of systematic research on the freewheeling diode can be avoided, thereby solving the problem of failure of the excitation system of the nuclear power plant emergency diesel generator due to the risk of overcurrent burning of the freewheeling diode, thereby improving the safety of the nuclear power plant.

[0105] Optionally, a processing circuit is used to determine a first multiple relationship between the minimum forward conduction voltage drop and the target voltage drop of each model of the freewheeling diode to be tested based on the performance parameters of multiple different models of the freewheeling diodes to be tested, wherein the first multiple relationship is used to characterize that the minimum forward conduction voltage drop is equal to N times the target voltage drop, N is a value greater than 1, and the target voltage drop is the voltage drop when the temperature of the freewheeling diode to be tested exceeds a preset temperature threshold and is damaged.

[0106] The processing circuit is also used to determine the target freewheeling diode from the freewheeling diodes to be detected of various types according to the first multiple relationship.

[0107] In this embodiment, the processing circuit can determine the first multiple relationship between the minimum forward conduction voltage drop and the target voltage drop of each type of freewheeling diode to be tested based on the performance parameters of multiple different types of freewheeling diodes to be tested, such as the shunting results, the first temperature value, the second temperature value and the change of the minimum forward conduction voltage drop of the freewheeling diode to be tested with different excitation currents, and combined with the target voltage drop of each freewheeling diode to be tested.

[0108] Specifically, the processing circuit determines that the key parameter that determines the shunting size of the freewheeling diode to be detected is the minimum forward conduction voltage drop of the freewheeling diode to be detected based on the performance parameters of multiple different types of freewheeling diodes to be detected. The larger the minimum forward conduction voltage drop of the freewheeling diode to be detected, the smaller the current share of the freewheeling diode to be detected. Then, excluding factors such as manufacturing process and environment, the processing circuit determines the minimum forward conduction voltage drop V of each type of freewheeling diode to be detected. F With the target voltage drop V nom The first multiple relationship between V F =N·V nom , target voltage drop V nom is the voltage drop when the temperature of the freewheeling diode to be detected exceeds the preset temperature threshold and is damaged, that is, the typical voltage drop parameter in the freewheeling diode manual, N is a value greater than 1, for example, N is greater than or equal to 1.6 and less than or equal to 2, and in this embodiment, N is 1.6. In other words, V F =1.6×V nom The minimum forward conduction voltage drop corresponding to the temperature rise of the freewheeling diode to be tested without causing damage to the component is 1.6 times the typical voltage drop parameter of the freewheeling diode to be tested.

[0109] Further, the processing circuit determines the target freewheeling diode from the freewheeling diodes of various types to be detected according to the first multiple relationship. Specifically, the processing circuit uses the freewheeling diodes of various types to be detected that meet the first multiple relationship as the target freewheeling diode.

[0110] Taking the first multiple relationship of 1.6 to 2 as an example, for the freewheeling diode 1 to be detected, the minimum forward conduction voltage drop determined by the detection module is equal to 1.5V, and the target voltage drop is equal to 1V. Therefore, the minimum forward conduction voltage drop and the target voltage drop of the freewheeling diode 1 to be detected do not satisfy the first multiple relationship. For the freewheeling diode 2 to be detected, the minimum forward conduction voltage drop is equal to 1.5V, and the target voltage drop is equal to 0.8V. The freewheeling diode 1 to be detected satisfies the first multiple relationship, and the processing circuit can use the freewheeling diode 2 to be detected as the target freewheeling diode.

[0111] Since the minimum forward conduction voltage drop of the target freewheeling diode satisfies the first multiple relationship with the target voltage drop, when the target freewheeling diode is used in an actual chopper power module, the shared current proportion and temperature rise will also be very small, and the target freewheeling diode is not easy to be overcurrent and burnt, avoiding the problem of excitation system failure of the nuclear power plant's emergency diesel generator and improving the safety of the nuclear power plant.

[0112] The processing circuit in this embodiment is used to determine the first multiple relationship between the minimum forward conduction voltage drop and the target voltage drop of each type of freewheeling diode to be detected based on the performance parameters of multiple different types of freewheeling diodes to be detected, wherein the first multiple relationship is used to characterize that the minimum forward conduction voltage drop is equal to N times the target voltage drop, N is a value greater than 1, and the target voltage drop is the voltage drop when the temperature of the freewheeling diode to be detected exceeds the preset temperature threshold and is damaged. The processing circuit is also used to determine the target freewheeling diode from the freewheeling diodes to be detected according to the first multiple relationship. Since the target freewheeling diode is determined from the freewheeling diodes to be detected according to the first multiple relationship, the target freewheeling diode determined can meet the actual operation requirements of the emergency diesel generator of the nuclear power plant, thereby improving the safety of the nuclear power plant.

[0113] This application also Figure 1 The circuit structure in the Figure 1 On this basis, a freewheeling diode can be connected in series next to the diode 113 as a backup to increase the minimum forward conduction voltage drop of the diode 113 and further improve safety.

[0114] Therefore, by using the performance detection device for the freewheeling diode provided in the present application, the target freewheeling diode can be determined from multiple different types of freewheeling diodes to be detected, so as to select the freewheeling diode in advance according to the actual operating requirements of the nuclear power plant emergency diesel generator.

[0115] On the one hand, the target freewheeling diode finally determined can significantly reduce or even avoid shunting, thereby effectively controlling the temperature rise of the target freewheeling diode, and ultimately improving the operating reliability of the target freewheeling diode, thereby improving the stability of the excitation system of the emergency diesel generator of the entire nuclear power plant. The freewheeling diode A used in the traditional method and the target freewheeling diode B determined in this application were used to carry out actual operation tests respectively. During the test, the temperature rise and shunting conditions of A and B were monitored in real time. The average data of the test of the shared current and the first temperature value of A and B under the same other conditions are shown in Table 4 below. Combined with Table 4, it can be seen that the current and the first temperature value shared by the target freewheeling diode B determined by the performance detection device of the freewheeling diode are significantly reduced.

[0116] Table 4 Effects

[0117] A B Shunt Current 1.24A 0.01A Temperature (20min) 101℃ 27.7℃

[0118] On the other hand, it also reduces the damage rate of the freewheeling diode components. After experimental testing, the damage rate of the freewheeling diode components has been reduced from the original 80% to less than 3%, which improves the reliability of the freewheeling diode and the reliability of the excitation system of the nuclear power plant's emergency diesel generator, thereby improving the safety of the nuclear power plant.

[0119] In addition, the performance detection device for the freewheeling diode provided in the present application can also effectively avoid the delay in the construction period caused by the overall accident handling due to the tripping caused by the failure of important components of the excitation system, as well as the delay in the progress of the main power line commissioning before the hot test caused by replacing equipment, restoring the unit status, and restarting. It can shorten the start-up test period of the emergency diesel generator of the nuclear power plant, save the manpower input of various professionals in installation, design, and commissioning, and greatly reduce the cost of engineering construction.

[0120] For example, the start-up test period of the emergency diesel generator of a nuclear power plant can be shortened by 2 days, and the construction period cost can be saved by 2×1000 (kW / h) / d×0.4 yuan / (kW / h)=8 million. If the excitation system of the emergency diesel generator of a nuclear power plant originally requires 0.66 times / year of operation and maintenance, and the single start-stop operation and maintenance cost of a single emergency diesel generator of a nuclear power plant is 1 million, after adopting the performance detection device of the freewheeling diode provided by this application, the normal operation and maintenance times can be reduced to 0.33 times / year, then the excitation system of the three emergency diesel generators of nuclear power plants can reduce the total operation and maintenance costs by 3×(0.66-0.33)×1 million=990,000 / year. In other words, this application can directly reduce the cost of 800+99=8.99 million yuan.

[0121] In summary, the performance detection device of the freewheeling diode used in this application establishes the performance parameters of the freewheeling diode to be detected, thereby providing a method that can meet the actual working conditions and can effectively judge whether the performance of the selected freewheeling diode meets the operating stability requirements of the excitation system of the emergency diesel generator of the nuclear power plant under different working conditions, in view of the current lack of systematic research on the freewheeling diode, that is, the model and performance of the freewheeling diode can be selected in advance according to the actual operating requirements of the emergency diesel generator of the nuclear power plant. The performance detection device of the freewheeling diode provided in this application is the first research and application in the construction of nuclear power plants. It has significant innovation and independence in technical analysis research and application of results, and is of great promotion and application value to both operating nuclear power units and newly built units.

[0122] Each module in the above-mentioned freewheeling diode performance detection device can be implemented in whole or in part by software, hardware, or a combination thereof. Each of the above-mentioned modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each of the above modules.

[0123] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0124] Based on the same inventive concept, the embodiment of the present application also provides a performance detection device for a freewheeling diode, which can detect the performance of the freewheeling diode. The implementation solution provided by the method is similar to the implementation solution recorded in the above method, and will not be repeated here.

[0125] Figure 6 FIG. 1 is an internal structure diagram of a computer device in an embodiment. In an embodiment of the present application, a computer device is provided. The computer device may be a server. The internal structure diagram thereof may be as shown in FIG. Figure 6 As shown. The computer device includes a processor, a memory and a network interface connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store relevant data. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a performance detection method for a freewheeling diode is implemented.

[0126] Those skilled in the art will understand that Figure 6The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0127] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0128] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0129] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0130] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A performance detection device for a freewheeling diode, characterized in that: The performance detection device comprises a power supply, a rectifier transistor, a parallel branch, a freewheeling diode to be detected, a processing circuit and a load circuit; the freewheeling diode to be detected is a freewheeling diode in a chopper power module; The power supply forms a first path between the rectifier transistor and the load circuit, and is used to supply power to the load circuit when the rectifier transistor is turned on, so as to generate an excitation current through the first path; The parallel branch and the freewheeling diode to be detected are connected in parallel to shunt the excitation current; The processing circuit is used to obtain the shunting result and determine the performance parameters of the freewheeling diode to be detected according to the shunting result; the performance parameters are used to select the freewheeling diode in the chopper power module.

2. The performance detection device according to claim 1, characterized in that: The parallel branch includes a first diode, a first end of the first diode and a first end of the freewheeling diode to be detected are connected to the source of the rectifier transistor and the first end of the load circuit, and a second end of the first diode and a second end of the freewheeling diode to be detected are connected to the second end of the power supply and the second end of the load circuit.

3. The performance detection device according to claim 1, characterized in that: The processing circuit includes a detection module and a processing module; The detection module is used to obtain the diversion result and send the diversion result to the processing module; The processing module is used to determine the performance parameter according to the diversion result.

4. The performance detection device according to claim 3, characterized in that: The shunting result includes at least one parameter of the current shared by the freewheeling diode to be detected and the current proportion shared by the freewheeling diode to be detected. The current proportion shared by the freewheeling diode to be detected is the ratio of the current shared by the freewheeling diode to be detected to the excitation current.

5. The performance detection device according to claim 4, characterized in that: The performance detection device also includes a first temperature sensor; The first temperature sensor is used to detect a first temperature value of the freewheeling diode to be detected, and send the first temperature value to the processing circuit; The processing circuit is used to determine the performance parameters of the freewheeling diode to be detected according to the first temperature value and the shunting result.

6. The performance detection device according to claim 5, characterized in that: The performance detection device also includes a second temperature sensor; The second temperature sensor is used to detect a second temperature value of the environment in which the freewheeling diode to be detected is located, and send the second temperature value to the processing circuit; The processing circuit is used to determine the performance parameters of the freewheeling diode to be detected according to the first temperature value, the second temperature value and the shunting result.

7. The performance detection device according to claim 6, characterized in that: The detection module is further used to obtain the minimum forward conduction voltage drop of the freewheeling diode to be detected; The processing circuit is further used to determine the performance parameters of the freewheeling diode to be detected based on the first temperature value, the second temperature value, the shunting result and the minimum forward conduction voltage drop of the freewheeling diode to be detected.

8. The performance detection device according to claim 7, characterized in that: The processing module is further used to determine, based on the performance parameters under different excitation currents, how the performance parameters of the freewheeling diode to be detected change with different excitation currents.

9. The performance detection device according to claim 8, characterized in that: The processing circuit is used to determine a target freewheeling diode from among the multiple different types of freewheeling diodes to be detected according to performance parameters of the multiple different types of freewheeling diodes to be detected.

10. The performance detection device according to claim 9, characterized in that: The processing circuit is used to determine a first multiple relationship between a minimum forward conduction voltage drop and a target voltage drop of each type of freewheeling diode to be detected according to the performance parameters of the plurality of different types of freewheeling diodes to be detected, wherein the first multiple relationship is used to characterize that the minimum forward conduction voltage drop is equal to N times the target voltage drop, N is a value greater than 1, and the target voltage drop is the voltage drop when the temperature of the freewheeling diode to be detected exceeds a preset temperature threshold and is damaged; The processing circuit is further used to determine the target freewheeling diode from the freewheeling diodes to be detected of each model according to the first multiple relationship.

Images