A thyristor junction temperature experimental detection system

Abstract

The present invention relates to the technical field of thyristors, and discloses a thyristor junction temperature experimental detection system, which includes a base and an experimental box. Inside the experimental box, there is a lower chassis and an upper lifting table. At the top of the lower chassis, a temperature measuring device is arranged at the central axis, and a lower conducting block is arranged at the outer circle position of the temperature measuring device. At the bottom of the upper lifting table, an upper conducting block is arranged. Inside the lower chassis, a positioning fixture is also arranged. The positioning fixture includes a plurality of clamping plates that move synchronously inward and outward above the lower chassis; the temperature measuring device includes a temperature sensor, a monitoring host, and a protective shell wrapped outside the temperature sensor and the monitoring host. The top of the temperature sensor is attached to the molybdenum sheet layer at the bottom of the thyristor chip, and the monitoring host is located below the temperature sensor. The monitoring host emits and receives optical signals to the temperature sensor. This thyristor junction temperature experimental detection system has the advantage of accurately measuring the temperature of the molybdenum sheet inside the thyristor housing and thus backtracking the junction temperature.

Description

Technical Field

[0001] The present invention relates to the technical field of thyristors, and particularly to a thyristor junction temperature experimental detection system. Background Art

[0002] A thyristor is a controllable semiconductor switching device with a four-layer (P1, N1, P2, N2) and three-junction (J1, J2, J3) structure. It has an anode on one side and a gate, an amplifying gate, and a cathode on the other side. Among them, the four-layer and three-junction structure below the amplifying gate forms an auxiliary thyristor, and the four-layer and three-junction structure below the cathode forms a main thyristor. Thyristors have the characteristics of high voltage resistance, large current conduction, and low power loss, and are widely used in power systems, pulsed power, electric furnaces, and the automotive industry. In the above application scenarios, as long as the thyristor works, power loss will occur, causing its junction temperature to rise. Due to the uneven current distribution, local overheating of the thyristor chip is likely to occur, leading to thyristor failure, which seriously affects the reliable operation of devices such as converter valves, pulsed drive sources, and electric furnaces. When manufacturing or using thyristors, in order to obtain the junction temperatures of thyristors with different specifications under different voltages, it is necessary to conduct junction temperature experimental tests on thyristors.

[0003] In the prior art, the patent with the patent application number CN202311375025.5 discloses a thyristor local junction temperature on-line detection system and a detection method, aiming to solve the problems of complex structure and low sensitivity of the existing junction temperature detection system. The detection system of the present invention consists of a main circuit unit, a trigger circuit, a temperature control unit, a data acquisition unit, and a local junction temperature calculation unit. The main circuit unit provides a working voltage and a conduction current with an adjustable waveform for the thyristor; the trigger circuit triggers the thyristor to conduct; the temperature control unit simulates different local junction temperatures of the thyristor; the small-ratio Rogowski coil in the data acquisition unit collects the parasitic trigger current, and the large-ratio Rogowski coil collects the anode current of the thyristor; by conducting a heating experiment on the thyristor, a relationship expression between the peak value of the trigger current and the local junction temperature of the thyristor is established, and based on the expression, the local junction temperature calculation unit detects the local junction temperature of the thyristor under the repetitive frequency discharge of the capacitor C1 in the main circuit unit. The detection system of the present invention is simple and greatly improves the sensitivity of local junction temperature measurement.

[0004] The above technology is for real-time on-line detection of the junction temperature, mainly involving the calculation of the junction temperature, and lacks a specific detection method for the junction temperature. The following problems need to be overcome in the detection of the junction temperature in the prior art: Due to the special structure and manufacturing process of the thyristor, the junction temperature of the thyristor cannot be measured directly. We can backtrace the junction temperature by detecting the temperature of the molybdenum sheet inside the tube shell; for round cake-shaped thyristors of different specifications and sizes, it is necessary to detect the temperature at a fixed position on the molybdenum sheet, which requires accurate positioning of the thyristor; during the experiment, the ambient temperature has a great influence on the junction temperature. Summary of the Invention

[0005] (I) Technical Problems to be Solved

[0006] In view of the deficiencies of the prior art, the present invention provides a thyristor junction temperature experimental detection system, which has the advantage of accurately measuring the temperature of the molybdenum sheet inside the thyristor shell and then backtracking the junction temperature, and solves the problem that due to the special structure and manufacturing process of the thyristor, the junction temperature of the thyristor cannot be measured actually.

[0007] (II) Technical Solution

[0008] To achieve the above object, the present invention provides the following technical solution:

[0009] A thyristor junction temperature experimental detection system includes a base and an experimental box. Inside the experimental box, there is a lower chassis and an upper lifting table that can be controlled to lift. At the top of the lower chassis, a temperature measuring device is arranged at the central axis, and a lower conducting block is arranged at the outer ring position of the temperature measuring device. At the bottom of the upper lifting table, there is an upper conducting block. The lower conducting block and the upper conducting block are used to input a controllable current into the thyristor chip. Inside the lower chassis, there is also a positioning fixture. The positioning fixture includes a plurality of clamping plates that move synchronously inward and outward above the lower chassis. When the thyristor chip is placed above the lower chassis, the clamping plates press against the side of the thyristor chip to align the middle position at the bottom of the thyristor chip with the temperature measuring device. After the upper lifting table descends, the upper conducting block and the lower conducting block are respectively connected to the upper and lower ends of the thyristor chip. The temperature measuring device includes a temperature sensor, a monitoring host, and a protective shell that wraps the temperature sensor and the monitoring host. The top of the temperature sensor is attached to the molybdenum sheet layer at the bottom of the thyristor chip, and the monitoring host is located below the temperature sensor. The monitoring host includes an emission port that emits a broadband pulsed optical signal to the temperature sensor and a reception port that receives the reflected optical signal.

[0010] Preferably, a gate circuit is also arranged inside the experimental box. The gate circuit is connected to the thyristor chip and is used to control the conduction of the thyristor chip.

[0011] Preferably, the temperature sensor is a fiber Bragg grating temperature sensor. The broadband pulsed optical signal emitted by the emission port is transmitted to the temperature sensor through an optical fiber. When the temperature of the molybdenum sheet layer changes, the period and refractive index of the fiber Bragg grating also change accordingly, resulting in a change in the wavelength of the reflected light of the temperature sensor.

[0012] Preferably, a spring is arranged at the bottom of the temperature measuring device. Under the action of the spring, the top of the temperature sensor is higher than the top of the lower conducting block. When the thyristor chip presses down the temperature sensor, the top of the temperature sensor is flush with the top of the lower conducting block. Its function is to make the top of the temperature sensor fit more closely to the bottom of the thyristor chip.

[0013] Preferably, a temperature control device for adjusting the temperature is further provided in the experimental chamber. The temperature control device is used to uniformly adjust the temperature in the experimental chamber and the base, so that the temperature in the experimental chamber and the base is maintained at a controlled temperature. The temperature control device is used to simulate the high temperature or low temperature generated in the environment during actual use.

[0014] Preferably, the positioning fixture includes: a middle gear installed in the base, the rotation axis of the middle gear being located below the central axis of the lower chassis; a plurality of side gears evenly arranged circumferentially outside the middle gear, each side gear being meshed with the middle gear on the side through a bevel gear; a lead screw, each lead screw being fixedly connected to the corresponding side gear, a thread being provided on the lead screw, and the thread directions of all lead screws being the same; a fixed seat, each fixed seat being connected to the corresponding lead screw, and the fixed seat being used to fix the lead screw to rotate in the base; a long slider, the bottom of each long slider being meshed with the corresponding lead screw, and a chute hole being provided in the lower chassis at the position corresponding to each long slider, and the top of the long slider passing through the corresponding chute hole; a clamping plate, installed on the top of each long slider, each clamping plate being circumferentially distributed on the side of the thyristor chip, and each clamping plate clamping the thyristor chip at the central axis, so that the middle position of the thyristor chip is aligned with the temperature sensor.

[0015] Preferably, in one fixed seat, a guide rail is further provided. The guide rail is a smooth straight rod. The long slider is provided with a through hole having the same size as the guide rail at the position corresponding to the guide rail. The guide rail passes through the through hole on the long slider, and the guide rail is used to improve the stability of the long slider.

[0016] Preferably, the bottom of the middle gear is connected to a motor. The motor drives the middle gear to rotate. The middle gear drives each lead screw to rotate. The lead screw drives the corresponding fixed seat to rotate. The rotation of the fixed seat drives the long slider to slide. The long slider drives the clamping plate to move inwards or outwards.

[0017] Preferably, a transparent window is further provided on the experimental chamber. The transparent window is made of a transparent material. A handle and a switch are provided on the transparent window. The experimental chamber, the base, and the transparent window are all made of heat-insulating materials. When the transparent window is closed, the inside and outside of the experimental chamber are kept isolated.

[0018] Preferably, a control panel is further provided on the base. The control panel is connected to a control and monitoring host. The data detected in the monitoring host is transmitted to the control panel through a cable; the upper lifting table is driven to lift by a motor, and the motor connected to the upper lifting table is connected to the control on the control panel through a cable; the control panel is also connected to the circuit for connecting the lower conductive block and the upper conductive block through a cable, and the control panel adjusts the magnitude of the current for connecting the lower conductive block and the upper conductive block; the motor connected to the middle gear is connected to the control panel through a cable, and the control panel clamps the side of the thyristor chip by controlling the rotation direction of the motor.

[0019] (III) Beneficial effects

[0020] Compared with the prior art, the present invention provides a thyristor junction temperature experimental detection system, which has the following beneficial effects:

[0021] 1. In the thyristor junction temperature experimental detection system, the lower chassis and the liftable upper lifting table are arranged in the experimental box to simulate the cover plates at the upper and lower ends inside the thyristor, and the lower conductive block and the upper conductive block are arranged to conduct electricity into the thyristor chip. A temperature measuring device is arranged on the lower chassis to measure the temperature of the molybdenum sheet layer at the bottom of the thyristor chip, and the junction temperature is traced back through the temperature of the molybdenum sheet layer, so as to simulate the usage scenario of the thyristor chip in the experimental box and detect the junction temperature under different currents.

[0022] 2. In the thyristor junction temperature experimental detection system, the temperature sensor is a fiber Bragg grating temperature sensor. The broadband pulsed optical signal emitted from the emission port is transmitted to the temperature sensor through the optical fiber. When the temperature of the molybdenum sheet layer changes, the period and refractive index of the fiber Bragg grating also change. The monitoring host can calculate the temperature of the molybdenum sheet layer more accurately by analyzing and recording the wavelength of the reflected light, thereby providing more accurate basic data for tracing back the junction temperature.

[0023] 3. In the thyristor junction temperature experimental detection system, a middle gear is arranged inside the base, the middle gear drives the side gears arranged circumferentially on the side, and the side gears drive the clamping plates to move synchronously inward and outward through the lead screws, so that the central axis of the thyristor chip placed above the lower chassis is aligned with the temperature sensor at the bottom, achieving the purpose of detecting the junction temperature at a fixed position for thyristor chips of different specifications.

[0024] 4. In the thyristor junction temperature experimental detection system, a spring is arranged at the bottom of the temperature measuring device, and the spring provides an upward thrust for the temperature sensor, making the temperature sensor fit more closely on the molybdenum sheet layer, thereby improving the measurement accuracy.

[0025] 5. In the thyristor junction temperature experimental detection system, a temperature control device is arranged in the experimental box, which better simulates the thyristor working at different temperatures. At the same time, the base, the experimental box and the transparent window are made of heat-insulating materials to reduce the influence of the external temperature on the experiment.

[0026] 6. In the thyristor junction temperature experimental detection system, the lifting of the upper lifting table, the clamping of the positioning fixture, and the conduction and magnitude of the current of the lower conductive block and the upper conductive block are controlled through the control panel, and the data transmitted in the monitoring host is stored and analyzed through the control panel, realizing integrated automatic control and convenient operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is an exploded view of a thyristor in the prior art.

[0028] Figure 2This is a schematic structural diagram of the thyristor junction temperature experimental detection system of the present invention when not in use.

[0029] Figure 3 This is a schematic structural diagram of the thyristor junction temperature experimental detection system of the present invention when placing the thyristor chip.

[0030] Figure 4 This is a schematic structural diagram of the thyristor junction temperature experimental detection system of the present invention during the experiment.

[0031] Figure 5 In the present invention Figure 3 sectional view.

[0032] Figure 6 In the present invention Figure 4 partial sectional view.

[0033] Figure 7 This is the working principle diagram of the temperature measurement device of the present invention.

[0034] Figure 8 This is a schematic structural diagram of the positioning fixture of the present invention.

[0035] Figure 9 This is a schematic structural diagram above the base of the present invention.

[0036] Figure 10 This is a partial structural schematic diagram of the positioning fixture of the present invention.

[0037] In the figure: 11, thyristor chip; 12, thyristor housing; 13, cover plate; 111, silicon wafer layer; 112, molybdenum wafer layer; 113, junction.

[0038] 21, base; 22, experimental box; 23, support feet; 24, control panel; 25, transparent window;

[0039] 31, lower chassis; 32, upper lifting platform; 311, lower conductive block; 321, upper conductive block;

[0040] 4, temperature measurement device; 41, temperature sensor; 42, monitoring host; 43, protective shell; 44, spring; 421, emission port; 422, receiving port;

[0041] 5, positioning fixture; 51, middle gear; 52, side gear; 53, lead screw; 54, fixed seat; 55, guide rail; 56, long slider; 57, clamping plate; 58, chute hole. Detailed implementation manners

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0043] Embodiment 1:

[0044] This embodiment provides a thyristor junction temperature experimental detection system with the following technical features.

[0045] As Figure 1 shown is an exploded view of a disc-shaped thyristor structure in the prior art. The thyristor includes an outer thyristor housing 12 and an internal thyristor chip 11. Two cover plates 13 are respectively arranged at the upper and lower ends of the thyristor chip 11 to fix the thyristor chip 11. When performing the thyristor junction temperature experiment detection, only the thyristor chip 11 part needs to be detected.

[0046] Please refer to Figures 2 - 10 , a thyristor junction temperature experimental detection system, including a base 21 and an experimental box 22. A lower chassis 31 and a liftable upper lifting table 32 are arranged in the experimental box 22. The lower chassis 31 and the upper lifting table 32 are used to simulate the cover plates 13 at the upper and lower ends in the thyristor. The upper lifting table 32 descends to clamp the thyristor chip 11 between the lower chassis 31 and the upper lifting table 32. A temperature measuring device 4 is arranged at the central axis of the top of the lower chassis 31. A lower conductive block 311 is arranged at the outer ring position of the temperature measuring device 4. An upper conductive block 321 is arranged at the bottom of the upper lifting table 32. The lower conductive block 311 and the upper conductive block 321 are used to input a controllable current into the thyristor chip 11. A positioning fixture 5 is also arranged in the lower chassis 31. The positioning fixture 5 includes a plurality of clamping plates 57 that move synchronously inward and outward above the lower chassis 31. When the thyristor chip 11 is placed above the lower chassis 31, the clamping plates 57 abut against the side of the thyristor chip 11 to align the middle position at the bottom of the thyristor chip 11 with the temperature measuring device 4. After the upper lifting table 32 descends, the upper conductive block 321 and the lower conductive block 311 are respectively connected to the upper and lower ends of the thyristor chip 11. A gate circuit is also arranged in the experimental box 22. The gate circuit is connected to the thyristor chip 11 and is used to control the conduction of the thyristor chip 11.

[0047] Through the above technical solution, the temperature measuring device 4 measures the temperature of the molybdenum layer 112, and then the temperature of the silicon layer 111 is retrogressed through the conjugate gradient algorithm. Among them, the temperature of the silicon layer 111 represents the temperature of the junction 113.

[0048] Further set, as Figures 2 - 9As shown in the figure, the temperature measuring device 4 includes a temperature sensor 41, a monitoring host 42, and a protective shell 43 wrapped around the outside of the temperature sensor 41 and the monitoring host 42. The protective shell 43 fixes the temperature sensor 41 and the monitoring host 42 together through a rib structure. The top of the temperature sensor 41 is attached to the molybdenum sheet layer 112 at the bottom of the thyristor chip 11. The monitoring host 42 is located below the temperature sensor 41. The monitoring host 42 includes a transmitting port 421 for transmitting a broadband pulsed optical signal to the temperature sensor 41 and a receiving port 422 for receiving the reflected optical signal.

[0049] Specifically, the temperature sensor 41 is a fiber Bragg grating temperature sensor. Specifically, the temperature sensor 41 is a Bragg fiber grating temperature sensor. The broadband pulsed optical signal emitted from the transmitting port 421 is transmitted to the temperature sensor 41 through an optical fiber. When the temperature of the molybdenum sheet layer 112 changes, the period and refractive index of the fiber grating also change accordingly, resulting in a change in the wavelength of the reflected light of the temperature sensor 41.

[0050] Grating reflection principle: When an optical signal passes through a fiber grating, the light that meets the conditions is reflected back to the receiving port 422 by the Bragg grating. This reflection process depends on the period and refractive index of the grating, both of which change with temperature. Therefore, when the temperature of the molybdenum sheet layer 112 changes, the period and refractive index of the fiber grating also change accordingly, resulting in a change in the wavelength of the reflected light. The monitoring host 42 can calculate the temperature of the molybdenum sheet layer 112 by analyzing and recording the wavelength of the reflected light.

[0051] Further, as Figures 2 - 9 shown, a spring 44 is provided at the bottom of the temperature measuring device 4. The spring 44 abuts against the bottom of the monitoring host 42. Since the temperature sensor 41 and the monitoring host 42 are fixed together under the connection of the protective shell 43, the top of the temperature sensor 41 is higher than the top of the lower conductive block 311 under the action of the spring 44. When the thyristor chip 11 presses down the temperature sensor 41, the top of the temperature sensor 41 is flush with the top of the lower conductive block 311, so that the top of the temperature sensor 41 fits more closely to the bottom of the thyristor chip 11.

[0052] Through the above technical solution, the spring 44 provides an upward thrust for the temperature sensor 41, making the temperature sensor 41 fit on the molybdenum sheet layer 112, thereby improving the measurement accuracy.

[0053] Further, as Figures 2 - 9 shown, when the thyristor is actually used, it will be affected by the heating of other circuits, resulting in an increase in the ambient temperature, and it will also change in temperature due to the natural environmental temperature rise and fall. In order to better simulate the junction temperature of the thyristor at different voltages at various temperatures, a temperature control device with adjustable temperature is also provided in the experimental chamber 22. The temperature control device is used to uniformly adjust the temperature in the experimental chamber 22 and the base 21.

[0054] Further provided, such as Figures 2 - 9 As shown, a transparent window 25 is further provided on the experimental box 22. The transparent window 25 is made of a transparent material, and a handle and a switch are provided on the transparent window 25. The experimental box 22, the base 21, and the transparent window 25 are all made of heat-insulating materials. When the transparent window 25 is closed, the inside and outside of the experimental box 22 are kept isolated.

[0055] Through the above technical solution, the temperatures inside the experimental box 22 and the base 21 can be maintained within a set range, reducing environmental errors.

[0056] Further provided, such as Figures 2 - 9 As shown, the positioning fixture 5 includes: a middle gear 51 installed inside the base 21, and the rotation axis of the middle gear 51 is located below the central axis of the lower chassis 31; side gears 52, at least three side gears 52 are circumferentially and evenly arranged outside the middle gear 51, and each side gear 52 is meshed with the middle gear 51 on the side through a bevel gear; lead screws 53, each lead screw 53 is fixedly connected to the corresponding side gear 52, and threads are provided on the lead screws 53; fixing seats 54, each fixing seat 54 is connected to the corresponding lead screw 53, and the fixing seat 54 is used to fix the lead screw 53 to rotate inside the base 21; long sliders 56, the bottom of each long slider 56 is meshed with the corresponding lead screw 53, and the lower chassis 31 is provided with a chute hole 58 at the position corresponding to each long slider 56, and the top of the long slider 56 passes through the corresponding chute hole 58; clamping plates 57, installed on the top of each long slider 56, and each clamping plate 57 is circumferentially distributed on the side of the thyristor chip 11.

[0057] Specifically, inside a fixing seat 54, a guide rail 55 is further provided. The guide rail 55 is a smooth straight rod, and the long slider 56 is provided with a through hole having the same size as the guide rail 55 at the position corresponding to the guide rail 55. The guide rail 55 passes through the through hole on the long slider 56 to improve the stability of the long slider 56.

[0058] Specifically, the bottom of the middle gear 51 is connected to a motor, the motor drives the middle gear 51 to rotate, the middle gear 51 drives each lead screw 53 to rotate, the lead screw 53 drives the corresponding fixing seat 54 to rotate, the rotation of the fixing seat 54 drives the long slider 56 to slide, and the long slider 56 drives the clamping plate 57 to move inwards or outwards.

[0059] Further provided, such as Figures 2 - 9As shown in the figure, a control panel 24 is also provided on the base 21. The control panel 24 is connected to the control monitoring host 42. The data detected in the monitoring host 42 is transmitted to the control panel 24 through a cable. The upper lifting table 32 is driven by a motor to lift and lower. The motor connected to the upper lifting table 32 is connected to the control on the control panel 24 through a cable. The control panel 24 is also connected to the circuit that controls the connection between the lower conductive block 311 and the upper conductive block 321 through a cable. The control panel 24 adjusts the magnitude of the current flowing through the circuit connecting the lower conductive block 311 and the upper conductive block 321. The motor connected to the middle gear 51 is connected to the control panel 24 through a cable. The control panel 24 controls the rotation direction of the motor to clamp the side of the thyristor chip 11 with the clamping plate 57.

[0060] Furthermore, as Figures 2 - 9 shown in the figure, four feet 23 are provided at the bottom of the base 21. Springs are provided between the feet 23 and the base 21 to improve the stability of the base 21.

[0061] Embodiment 2:

[0062] This embodiment provides a thyristor junction temperature experimental detection system, which has the following technical features in addition to the technical solutions of the above embodiment.

[0063] This embodiment provides a specific implementation manner in which three side gears 52 are wrapped around the outside of the middle gear 51. A thyristor junction temperature experimental detection system includes a base 21 and an experimental box 22. A lower chassis 31 and a liftable and controllable upper lifting table 32 are arranged in the experimental box 22. The lower chassis 31 and the upper lifting table 32 are used to simulate the upper and lower cover plates 13 of the thyristor. The upper lifting table 32 descends to clamp the thyristor chip 11 between the lower chassis 31 and the upper lifting table 32. A temperature measuring device 4 is arranged at the central axis of the top of the lower chassis 31. A lower conductive block 311 is arranged at the outer ring position of the temperature measuring device 4. An upper conductive block 321 is arranged at the bottom of the upper lifting table 32. The lower conductive block 311 and the upper conductive block 321 are used to input a controllable current into the thyristor chip 11. A positioning fixture 5 is also arranged in the lower chassis 31. The positioning fixture 5 includes three clamping plates 57 that move synchronously inward and outward above the lower chassis 31. When the thyristor chip 11 is placed above the lower chassis 31, the clamping plates 57 abut against the side of the thyristor chip 11 to align the middle position of the bottom of the thyristor chip 11 with the temperature measuring device 4.

[0064] Specifically, the positioning fixture 5 includes: a middle gear 51 installed inside the base 21, with the rotation axis of the middle gear 51 located below the central axis of the lower chassis 31; side gears 52, three side gears 52 are evenly arranged circumferentially outside the middle gear 51, the included angle between each side gear 52 is 120 degrees, and each side gear 52 is meshed with the middle gear 51 on the side through bevel gears; lead screws 53, each lead screw 53 is fixedly connected to the corresponding side gear 52, and threads are provided on the lead screws 53; fixed seats 54, each fixed seat 54 is connected to the corresponding lead screw 53, and the fixed seat 54 is used to fix the lead screw 53 to rotate inside the base 21; long sliders 56, the bottom of each long slider 56 is meshed with the corresponding lead screw 53, and the lower chassis 31 is provided with chute holes 58 at positions corresponding to each long slider 56, and the top of the long slider 56 passes through the corresponding chute hole 58; clamping plates 57, installed on the top of each long slider 56, and each clamping plate 57 is circumferentially distributed on the side of the thyristor chip 11.

[0065] Working principle: After opening the transparent window 25, place the thyristor chip 11 at the middle position of the lower chassis 31, connect the gate circuit to the gate of the thyristor chip 11, and close the transparent window 25; drive the middle gear 51 to rotate by controlling the motor, the middle gear 51 drives the multiple side gears 52 and lead screws 53 on the side to rotate synchronously, and through the transmission of the lead screw sliders, each long slider 56 moves inward synchronously. Since the clamping plates 57 at the top of the long sliders 56 are circumferentially distributed above the lower chassis 31, when the clamping plates 57 clamp the thyristor chip 11, the central axis at the bottom of the thyristor chip 11 will be aligned with the temperature sensor 41. Therefore, regardless of the size of the thyristor chip 11 being tested, the temperature sensor 41 can be automatically and accurately aligned with the central axis at the bottom of the thyristor chip 11 for detection; after clamping the thyristor chip 11, start the motor connected to the upper lifting platform 32, so that the upper lifting platform 32 descends to the top of the thyristor chip 11, so that the lower conducting block 311 and the upper conducting block 321 clamp the upper and lower ends of the thyristor chip 11; under the downward clamping action of the upper lifting platform 32, the spring 44 at the bottom of the temperature measuring device 4 bends downward, making the top surface of the temperature sensor 41 flush with the top surface of the lower conducting block 311, making the temperature sensor 41 fit the thyristor chip 11 more closely; start the circuits of the lower conducting block 311 and the upper conducting block 321 through the control panel 24, and at the same time start the gate circuit to make the circuit conduct. At this time, the temperature measuring device 4 detects the temperature of the molybdenum layer 112 through the temperature sensor 41, and the ambient temperature can also be changed through the temperature control device in the experimental box 22 to simulate the change of the junction temperature in various scenarios.

[0066] In summary, in the thyristor junction temperature experimental detection system, the lower chassis 31 and the liftable upper lifting table 32 are arranged in the experimental box 22 to simulate the upper and lower cover plates 13 inside the thyristor, and the lower conductive block 311 and the upper conductive block 321 are arranged to conduct electricity into the thyristor chip 11. A temperature measuring device 4 is arranged on the lower chassis 31 to measure the temperature of the molybdenum sheet layer 112 at the bottom of the thyristor chip 11, and the junction temperature is traced back through the temperature of the molybdenum sheet layer 112, so as to simulate the usage scenario of the thyristor chip 11 in the experimental box 22 and detect the junction temperature under different currents.

[0067] In the thyristor junction temperature experimental detection system, the temperature sensor 41 is a fiber Bragg grating temperature sensor. The broadband pulsed optical signal emitted from the emission port 421 is transmitted to the temperature sensor 41 through an optical fiber. When the temperature of the molybdenum sheet layer 112 changes, the period and refractive index of the fiber Bragg grating also change accordingly. By analyzing and recording the wavelength of the reflected light, the monitoring host 42 can calculate the temperature of the molybdenum sheet layer 112 more accurately, thereby providing more accurate basic data for backtracking the junction temperature.

[0068] In the thyristor junction temperature experimental detection system, a middle gear 51 is arranged in the base 21. The middle gear 51 drives the side gears 52 arranged circumferentially on the side. The side gears 52 drive the clamping plate 57 to move synchronously inward and outward through the lead screw 53, so that the central axis of the thyristor chip 11 placed above the lower chassis 31 is aligned with the temperature sensor 41 at the bottom, achieving the purpose of detecting and fixing the junction temperature at a fixed position for thyristor chips 11 of different specifications.

[0069] In the thyristor junction temperature experimental detection system, a spring 44 is arranged at the bottom of the temperature measuring device 4. The spring 44 provides an upward thrust for the temperature sensor 41, making the temperature sensor 41 fit more closely on the molybdenum sheet layer 112, thereby improving the measurement accuracy.

[0070] In the thyristor junction temperature experimental detection system, a temperature control device is arranged in the experimental box 22 to better simulate the working scenarios of the thyristor at different temperatures. At the same time, the base 21, the experimental box 22, and the transparent window 25 are made of heat-insulating materials to reduce the influence of the external temperature on the experiment.

[0071] In the thyristor junction temperature experimental detection system, the lifting of the upper lifting table 32, the clamping of the positioning fixture 5, and the conduction and magnitude of the current in the lower conductive block 311 and the upper conductive block 321 are controlled through the control panel 24, and the data transmitted in the monitoring host 42 is stored and analyzed through the control panel 24, realizing integrated automatic control and convenient operation.

[0072] It should be noted that, in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0073] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A thyristor junction temperature experimental detection system, characterized in that: The invention comprises a base (21) and an experimental box (22), wherein a lower chassis (31) and an upper lifting platform (32) which can be raised and lowered are arranged in the experimental box (22), a temperature measuring device (4) is arranged at the center axis of the top of the lower chassis (31), a lower conductive block (311) is arranged at the outer ring position of the temperature measuring device (4), and an upper conductive block (321) is arranged at the bottom of the upper lifting platform (32), and the lower conductive block (311) and the upper conductive block (321) are used to input a controllable current into a thyristor chip (11); A positioning fixture (5) is also provided in the lower chassis (31), and the positioning fixture (5) comprises a plurality of clamping plates (57) located above the lower chassis (31) and moving inward and outward synchronously. When the thyristor chip (11) is placed above the lower chassis (31), the clamping plates (57) press against the side of the thyristor chip (11) so that the middle position of the bottom of the thyristor chip (11) is aligned with the temperature measuring device (4). After the upper lifting platform (32) descends, the upper conductive block (321) and the lower conductive block (311) are respectively connected to the upper and lower ends of the thyristor chip (11); The temperature measuring device (4) comprises a temperature sensor (41), a monitoring host (42), and a protective shell (43) wrapped around the outside of the temperature sensor (41) and the monitoring host (42); the top of the temperature sensor (41) is attached to the molybdenum sheet layer (112) at the bottom of the thyristor chip (11); the monitoring host (42) is located below the temperature sensor (41); and the monitoring host (42) comprises a transmitting port (421) for transmitting a wide-spectrum pulse optical signal to the temperature sensor (41) and a receiving port (422) for receiving a reflected optical signal.

2. A thyristor junction temperature experimental detection system according to claim 1, characterized in that: A gate circuit is also provided in the experimental box (22); the gate circuit is connected to the thyristor chip (11) and is used to control the conduction of the thyristor chip (11).

3. A thyristor junction temperature experimental detection system according to claim 2, characterized in that: The temperature sensor (41) is a fiber grating temperature sensor, and the wide-spectrum pulse light signal emitted by the emission port (421) is transmitted to the temperature sensor (41) via the optical fiber.

4. A thyristor junction temperature experimental detection system according to claim 3, characterized in that: A spring (44) is provided at the bottom of the temperature measuring device (4); the top of the temperature sensor (41) is higher than the top of the lower conductive block (311) under the action of the spring (44); when the thyristor chip (11) presses down on the temperature sensor (41), the top of the temperature sensor (41) is flush with the top of the lower conductive block (311), thereby making the top of the temperature sensor (41) more closely attached to the bottom of the thyristor chip (11).

5. A thyristor junction temperature experimental detection system according to claim 1, characterized in that: A temperature control device capable of adjusting the temperature is also provided in the experimental box (22), and the temperature control device is used to evenly adjust the temperature in the experimental box (22) and the base (21).

6. A thyristor junction temperature experimental detection system according to claim 1, characterized in that: The positioning fixture (5) comprises: A middle gear (51) is installed in the base (21), and the rotation axis of the middle gear (51) is located below the middle axis of the lower chassis (31); Side gears (52), wherein a plurality of side gears (52) are evenly arranged on the circumference of the outer side of the middle gear (51), and each side gear (52) is meshed with a side surface of the middle gear (51) through a bevel gear; Screw rods (53), each screw rod (53) is fixedly connected to a corresponding side gear (52), and a thread is arranged on the screw rod (53); A fixed seat (54), each fixed seat (54) is connected to a corresponding screw rod (53), and the fixed seat (54) is used to fix the screw rod (53) in the base (21) for rotation; Long sliders (56), the bottom of each long slider (56) is meshed with the corresponding screw rod (53), the lower chassis (31) is provided with a slide slot hole (58) at a position corresponding to each long slider (56), and the top of the long slider (56) passes through the corresponding slide slot hole (58); A clamping plate (57) is installed on the top of each long slider (56), and each clamping plate (57) is circumferentially distributed on the side of the thyristor chip (11).

7. A thyristor junction temperature experimental detection system according to claim 6, characterized in that: A guide rail (55) is also arranged in a fixed seat (54), wherein the guide rail (55) is a smooth straight rod, and the long slider (56) is provided with a through hole of the same size as the guide rail (55) at a position corresponding to the guide rail (55), and the guide rail (55) passes through the through hole on the long slider (56).

8. A thyristor junction temperature experimental detection system according to claim 6, characterized in that: The bottom of the middle gear (51) is connected to a motor, the motor drives the middle gear (51) to rotate, the middle gear (51) drives each screw rod (53) to rotate, the screw rod (53) drives the corresponding fixed seat (54) to rotate, the fixed seat (54) rotates to drive the long slider (56) to slide, and the long slider (56) drives the clamping plate (57) to move inward or outward.

9. The thyristor junction temperature experimental detection system according to claim 1, characterized in that: The experimental box (22) is also provided with a transparent window (25), the transparent window (25) is made of a transparent material, a handle and a switch are provided on the transparent window (25), the experimental box (22), the base (21) and the transparent window (25) are all made of heat-insulating materials, and when the transparent window (25) is closed, the inside and outside of the experimental box (22) remain isolated.

10. A thyristor junction temperature experimental detection system according to claim 8, characterized in that: The base (21) is also provided with a control panel (24), the control panel (24) is connected to a control monitoring host (42), and data detected in the monitoring host (42) is transmitted to the control panel (24) via a cable; The upper lifting platform (32) is driven to rise and fall by a motor, and the motor connected to the upper lifting platform (32) is controlled on the control panel (24) through a cable connection; the control panel (24) also controls the circuit connecting the lower conductive block (311) and the upper conductive block (321) through a cable connection, and the control panel (24) adjusts the magnitude of the current connecting the lower conductive block (311) and the upper conductive block (321); the motor connected to the middle gear (51) is connected to the control panel (24) through a cable, and the control panel (24) controls the rotation direction of the motor so that the clamping plate (57) clamps the side of the thyristor chip (11).

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