A power device temperature rise detection device and method

Abstract

This invention provides a power device temperature rise detection apparatus and method, relating to the field of power device temperature rise detection. The detection apparatus includes an optical path system and a signal processing system. The optical path system includes a light source, a beam splitter group, a measuring mirror, and a reference mirror. The measuring mirror can be fixed to the power device under test. The light provided by the light source is split into two beams by the beam splitter group. The two beams are reflected back to the beam splitter group by the measuring mirror and the reference mirror, respectively, producing a Michelson interference phenomenon. The signal processing system is used to acquire and process the interference fringe signal, and the calculation software obtains the displacement of the measuring mirror caused by the temperature rise of the power device, thereby deducing the temperature rise of the power device under test. Using this detection apparatus for temperature rise measurement is a non-contact measurement, effectively avoiding measurement deviations in traditional thermocouple measurements. Furthermore, by utilizing the principle of light interference for displacement measurement and then deducing the temperature rise, it offers high sensitivity and accuracy, ensuring the reliability of power device temperature rise detection.

Description

Technical Field

[0001] This invention relates to the field of power device temperature rise detection technology, and more specifically, to a power device temperature rise detection device and method. Background Technology

[0002] Power devices play a crucial role in air conditioning circuits, primarily used to boost voltage and improve power factor. Their temperature rise characteristics, as a core performance indicator, directly affect the reliability and lifespan of the system.

[0003] In existing technologies, temperature rise detection of power devices mainly relies on contact temperature measurement methods, among which thermocouple measurement is widely used. However, thermocouple installation requires precise fixing of the probe to the surface of the power device under test. If the fixation is not secure or the contact is poor, the probe is prone to falling off, affecting the continuity and reliability of the measurement. Furthermore, thermocouples need to be placed at the wafer locations of the power device. Due to significant structural differences between devices from different manufacturers, the accuracy of manual placement is difficult to ensure, resulting in measurement results lacking representativeness. Therefore, thermocouple measurement suffers from low efficiency and limited accuracy, exhibiting certain limitations.

[0004] With the development of intelligent and efficient technologies in the air conditioning industry, higher requirements are being placed on the accuracy and efficiency of temperature rise measurement for key power devices. Therefore, a more accurate temperature rise measurement technology needs to be developed. Summary of the Invention

[0005] The first objective of this invention is to provide a power device temperature rise detection device to solve the technical problem of low accuracy in power device temperature rise measurement in the prior art.

[0006] The present invention provides a power device temperature rise detection device for detecting the temperature rise of a power device. The detection device includes an optical path system and a signal processing system. The optical path system includes a light source, a beam splitter group, a measuring mirror, and a reference mirror. The measuring mirror can be fixed to the power device under test. The light provided by the light source is split into two beams by the beam splitter group. The two beams can be reflected back to the beam splitter group by the measuring mirror and the reference mirror, respectively, and a Michelson interference phenomenon is generated. The signal processing system is used to collect and process the interference fringe signal, obtain the displacement of the measuring mirror, and deduce the temperature rise of the power device under test.

[0007] Furthermore, the beam splitter group can divide the interference fringe signal generated by the received reflected light into four paths, with each pair of the four signals having a 90° phase difference. The signal processing system includes four photodetectors, a signal processing circuit, a data acquisition card, and calculation software. The four photodetectors are used to acquire one of the interference fringe signals and convert it into an electrical signal. The signal processing circuit is used to process the converted electrical signal. The data acquisition card is used to acquire and store the signal data processed by the signal processing circuit and transmit it to the calculation software. The calculation software is used to calculate the displacement of the measuring mirror and the temperature rise of the power device under test.

[0008] Furthermore, the signal processing circuit sequentially includes a signal amplification circuit, a DC filter circuit, a phase-locked loop circuit, and an automatic gain control circuit, which are used to amplify the signal, filter the DC component in the signal, lock the phase difference of the signal, and control the amplitude of the output signal, respectively.

[0009] Furthermore, the signal processing system also includes an oscilloscope, which is used to display the two reflected light signals after being processed by the signal processing circuit.

[0010] Furthermore, the light source includes a laser.

[0011] Furthermore, the light source includes a semiconductor laser.

[0012] Furthermore, each beam splitter in the beam splitter group is a prism.

[0013] The power device temperature rise detection device provided by this invention can produce the following beneficial effects: The power device temperature rise detection device provided by this invention is based on the displacement measurement function of a Michelson interferometer. By arranging a measuring mirror on the surface of the power device under test, the device measures the positional change of the measuring mirror or the reflected light on it using the principle of optical interference to obtain the thermal expansion of the power device under test, and further deduce the temperature rise of the power device under test. It is evident that the temperature rise measurement using the power device temperature rise detection device provided by this invention is a non-contact measurement, which can effectively avoid the measurement deviation caused by poor thermocouple contact or insecure fixing in traditional thermocouple measurements. Furthermore, by using the principle of light interference for displacement measurement and then deducing the temperature rise, it has high sensitivity and high accuracy, ensuring the reliability of power device temperature rise detection. This provides an efficient and reliable solution for the research, development, production, and performance optimization of air conditioning controllers.

[0014] The second objective of this invention is to provide a method for detecting the temperature rise of power devices, so as to solve the technical problem of low accuracy in the measurement of temperature rise of power devices in the prior art.

[0015] The power device temperature rise detection method provided by this invention uses the aforementioned power device temperature rise detection device to detect the temperature rise of the power device under test. The detection method includes: The measuring mirror is fixed to the power device under test; When the detection device is turned on, the light emitted by the light source is split into two beams by the beam splitter. The two beams are reflected by the measuring mirror and the reference mirror, respectively. The optical path system is adjusted so that the two reflected beams produce Michelson interference. The signal processing system acquires and processes the interference fringe signal to obtain the displacement of the measuring mirror and deduce the temperature rise of the power device under test.

[0016] Furthermore, the signal processing system includes an oscilloscope, and the detection method includes: adjusting the optical path system until the signal displayed on the oscilloscope is an ideal circle before starting the detection.

[0017] The power device temperature rise detection method provided by this invention can produce the following beneficial effects: The power device temperature rise detection method provided by this invention utilizes the aforementioned detection device and, based on the displacement measurement function of a Michelson interferometer, measures the positional changes of the measuring mirror or the reflected light on the power device using the principle of optical interference. This yields the thermal expansion of the power device and allows for the deduction of its temperature rise. As can be seen, the power device temperature rise detection method provided by this invention is a non-contact measurement method, effectively avoiding measurement deviations caused by poor thermocouple contact or insecure fixing in traditional thermocouple measurements. Furthermore, by utilizing the principle of light interference for displacement measurement and subsequent temperature rise deduction, it exhibits high sensitivity and accuracy, ensuring the reliability of power device temperature rise detection. This provides an efficient and reliable solution for the research, development, production, and performance optimization of air conditioning controllers.

[0018] A third objective of this invention is to provide a computer-readable storage medium that stores a computer program / instructions and a bit stream thereon. When the computer program / instructions are executed by a processor, they acquire signal data processed by the signal processing circuit and calculate the temperature rise of the power device under test, thereby generating the bit stream. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 This is a simplified schematic diagram of a power device temperature rise detection device provided in an embodiment of the present invention.

[0021] Explanation of reference numerals in the attached figures: 010 - Power device under test; 100 - Light source; 200 - Beam splitter group; 310 - Measuring mirror; 320 - Reference mirror; 400 - Photodetector; 500 - Signal processing circuit; 600 - Data acquisition card; 700 - Calculation software. Detailed Implementation

[0022] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0023] This embodiment provides a power device temperature rise detection device for detecting the temperature rise of power devices, such as... Figure 1 As shown, the detection device includes an optical path system and a signal processing system. The optical path system includes a light source 100, a beam splitter group 200, a measuring mirror 310, and a reference mirror 320. The measuring mirror 310 can be fixed to the power device under test 010. The light provided by the light source 100 is split into two beams by the beam splitter group 200. The two beams can be reflected back to the beam splitter group 200 by the measuring mirror 310 and the reference mirror 320, respectively, and a Michelson interference phenomenon is generated. The signal intensity of the interference fringe signal will change periodically with the movement of the measuring mirror 310. The signal processing system is used to collect and process the interference fringe signal, obtain the displacement of the measuring mirror 310, and deduce the temperature rise of the power device under test 010.

[0024] The power device temperature rise detection device provided in this embodiment is based on the displacement measurement function of a Michelson interferometer. By arranging a measuring mirror 310 on the surface of the power device 010 under test, the device measures the positional change of the measuring mirror 310 or its reflected light using the principle of optical interference, thereby obtaining the thermal expansion of the power device 010 and further deducing its temperature rise. It is evident that the temperature rise measurement using the power device temperature rise detection device provided in this embodiment is a non-contact measurement, effectively avoiding measurement deviations caused by poor thermocouple contact or insecure fixing in traditional thermocouple measurements. Furthermore, by utilizing the principle of optical interference for displacement measurement and subsequent temperature rise deduction, it exhibits high sensitivity and accuracy, ensuring the reliability of power device temperature rise detection. This provides an efficient and reliable solution for the research, development, production, and performance optimization of air conditioning controllers.

[0025] Specifically, in this embodiment, the light source 100 is a laser, and more specifically, a semiconductor laser. Laser light sources have characteristics such as good monochromaticity, strong directionality, high brightness, and good coherence, while semiconductor lasers have advantages such as high efficiency, small size, light weight, and low cost. Of course, in other embodiments of this application, the light source 100 is not limited to a laser, but can also be other light sources that meet the requirements. Even if it is a laser, it is not limited to a semiconductor laser, but can also be other types of lasers.

[0026] Specifically, in this embodiment, each beam splitter in the beam splitter group 200 is a prism. It should be emphasized here that the beam splitter group 200 includes more than one beam splitter. Figure 1 This is for simplification purposes only.

[0027] Specifically, in this embodiment, the beam splitter group 200 can divide the interference fringe signal generated by the received reflected light into four paths, with each pair of the four signals having a 90° phase difference. The signal processing system includes four photodetectors 400, a signal processing circuit 500, a data acquisition card 600, and calculation software 700. The four photodetectors 400 are used to acquire one interference fringe signal and convert it into an electrical signal. The signal processing circuit 500 is used to process the converted electrical signal. The data acquisition card 600 is used to acquire and store the signal data processed by the signal processing circuit 500 and transmit it to the calculation software 700. The calculation software 700 is used to calculate the displacement of the measuring mirror 310 and the temperature rise of the measured power device 010. Furthermore, in this embodiment, the calculation software 700 also displays the calculated temperature rise data.

[0028] More specifically, in this embodiment, the signal processing circuit 500 sequentially includes a signal amplification circuit, a DC filter circuit, a phase-locked loop (PLL) circuit, and an automatic gain control (AGC) circuit. These circuits are used to amplify the signal, filter the DC component in the signal, lock the phase difference of the signal to ensure orthogonality, and control the amplitude of the output signal to ensure that the signal strength is always within a predetermined range. Interference signals commonly suffer from problems such as DC bias, unequal amplitude, and poor orthogonality, collectively referred to as Heidemann error. These correspond to phenomena such as the Lissajous circle's center not being at zero, the shape being elliptical, and the major axis of the ellipse not being on the X-axis. Therefore, the signal processing circuit 500 designed in this embodiment first adjusts the signal amplification factor, then extracts and filters the DC component in the signal, then uses a PLL circuit to ensure signal orthogonality, and finally uses an AGC circuit to ensure that the signal strength is always within a predetermined range.

[0029] In this embodiment, the signal processing system also includes an oscilloscope, which is used to display the two reflected light signals processed by the signal processing circuit 500. When adjusting the optical path, measurement can begin when the processed signal, as observed on the oscilloscope, is an ideal circle.

[0030] The following combination Figure 1 The principle of the power device temperature rise detection device provided in this embodiment is summarized as follows: The beam emitted by the semiconductor laser is split into two paths after passing through a beam splitter: one is a reference beam and the other is a measurement beam. The reference beam is reflected by a reference mirror 320, and the measurement beam is reflected by a measurement mirror 310 attached to the power device under test 010. The two reflected beams interfere with each other, forming an interference fringe signal with alternating bright and dark edges, which is received by a photodetector 400. When the power device under test 010 moves along the optical path, the optical path difference and phase difference between the measurement beam and the reference beam change. For every wavelength change in the optical path difference, the phase changes by 2π, and the interference fringes also periodically alternate between bright and dark. The corresponding light intensity signal received by the photodetector 400 also changes periodically. After the signal processing circuit 500 eliminates the Heidemann error, the signal is saved to the data acquisition card 600. The calculation software 700 calculates the number of cycles of signal intensity change, and the displacement of the power device under test 010 can be measured by equation (1).

[0031] x=( φ / 2π)×λ / 2=N×λ / 2(1) In the formula, x is the displacement. φ is the total phase shift, λ is the wavelength of the laser, and N is the number of signal cycles.

[0032] In temperature rise detection, the surface of the power device 010 under test will expand due to thermal changes with temperature rise, and the amount of expansion can be obtained from equation (2). L=α×ΔT(2) In the formula, α is the coefficient of thermal expansion of the material, that is, the amount of elongation of the material per unit length for every 1℃ increase in temperature; ΔT is the change in temperature.

[0033] Measure the thermal expansion of the power device. L, which is the displacement. x, combined with equations (1) and (2), i.e. equation (3), can be used to calculate the temperature rise of the device.

[0034] T=ΔL / α=Nλ / (2α)(3) This embodiment also provides a method for detecting the temperature rise of a power device. The method uses the aforementioned power device temperature rise detection device to detect the temperature rise of the power device 010 under test. The detection method includes: Fix the measuring mirror 310 to the power device 010 under test; When the detection device is turned on, the light emitted by the light source 100 is split into two beams by the beam splitter group 200. The two beams are reflected by the measuring mirror 310 and the reference mirror 320 respectively. The optical path system is adjusted so that the two reflected beams produce Michelson interference. The signal processing system acquires and processes the interference fringe signal to obtain the displacement of the measuring mirror 310, and then deduces the temperature rise of the power device 010 under test.

[0035] Specifically, in this embodiment, the signal processing system includes an oscilloscope, and the detection method includes: adjusting the optical path system until the signal displayed on the oscilloscope is an ideal circle before starting the detection.

[0036] In summary, the process of detecting the temperature rise of power devices using the detection device provided in this embodiment can be outlined as follows: Attach the measuring mirror 310 to the surface of the power device 010 under test, turn on the laser, and adjust the optical path until the reflected light from the reference light and the measuring light completely overlap and interfere, which is received by the photodetector 400. Connect the signal to an oscilloscope and observe the quality of the Lissajous circle formed by the two signals. When it is observed that the signal processed by the signal processing circuit 500 is an ideal circle, the measurement begins.

[0037] During the measurement process, the measuring mirror 310 moves as the power device under test 010 expands due to heat. The photodetector 400 receives the light intensity signal, the signal processing circuit 500 processes the signal and stores it in the data acquisition card 600, and the calculation software 700 calculates the temperature rise of the power device under test 010 in real time and saves the data.

[0038] In summary, the power device temperature rise detection device and method provided in this embodiment, based on the displacement measurement function of the Michelson interferometer, obtains the thermal expansion of the power device 010 by measuring the displacement of the measuring mirror 310 on the power device 010 under test, and then infers its temperature rise. Compared with the traditional thermocouple detection method, it has the following advantages: (1) It uses an optical non-contact method to measure the device temperature rise, avoiding the disturbance of the temperature and thermal field of the measured point by the probe itself in the traditional thermocouple method; (2) It has nanometer-level measurement accuracy, and can reflect the temperature change of the device in real time with higher accuracy and faster response speed, effectively improving the reliability of measurement; (3) It has higher spatial resolution, and can measure the local temperature rise of a small area, and can achieve more accurate temperature rise point testing compared with thermocouple; (4) Compared with thermocouple, it can select measurement points more flexibly, without the need for additional points, and can effectively avoid measurement errors caused by point deviation in thermocouple measurement.

[0039] This embodiment also provides a computer-readable storage medium storing a computer program / instruction and a bit stream. When the computer program / instruction is executed by the processor, it acquires the signal data processed by the signal processing circuit 500 and calculates the temperature rise of the power device 010 under test, generating the bit stream mentioned above.

[0040] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0041] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A power device temperature rise detection device, characterized in that, The detection device is used to detect the temperature rise of power devices. The detection device includes an optical path system and a signal processing system. The optical path system includes a light source (100), a beam splitter group (200), a measuring mirror (310), and a reference mirror (320). The measuring mirror (310) can be fixed to the power device (010) under test. The light provided by the light source (100) is split into two beams by the beam splitter group (200). The two beams can be reflected back to the beam splitter group (200) by the measuring mirror (310) and the reference mirror (320) respectively, and a Michelson interference phenomenon is generated. The signal processing system is used to collect and process interference fringe signals, obtain the displacement of the measuring mirror (310), and deduce the temperature rise of the power device under test (010).

2. The power device temperature rise detection device according to claim 1, characterized in that, The beam splitter group (200) can divide the interference fringe signal generated by the received reflected light into four paths, and the phase difference between each pair of the four paths is 90°. The signal processing system includes four photodetectors (400), a signal processing circuit (500), a data acquisition card (600), and a calculation software (700). The four photodetectors (400) are used to acquire one path of the interference fringe signal and convert it into an electrical signal. The signal processing circuit (500) is used to process the converted electrical signal. The data acquisition card (600) is used to acquire and store the signal data processed by the signal processing circuit (500) and transmit it to the calculation software (700). The calculation software (700) is used to calculate the displacement of the measuring mirror (310) and the temperature rise of the power device under test (010).

3. The power device temperature rise detection device according to claim 2, characterized in that, The signal processing circuit (500) includes, in sequence, a signal amplification circuit, a DC filter circuit, a phase-locked loop circuit, and an automatic gain control circuit, which are used to amplify the signal, filter the DC component in the signal, lock the phase difference of the signal, and control the amplitude of the output signal, respectively.

4. The power device temperature rise detection device according to claim 2 or 3, characterized in that, The signal processing system also includes an oscilloscope for displaying the two reflected light signals processed by the signal processing circuit (500).

5. The power device temperature rise detection device according to claim 4, characterized in that, The light source (100) includes a laser.

6. The power device temperature rise detection device according to claim 5, characterized in that, The light source (100) includes a semiconductor laser.

7. The power device temperature rise detection device according to claim 4, characterized in that, Each beam splitter in the beam splitter group (200) is a prism.

8. A method for detecting the temperature rise of a power device, characterized in that, The power device temperature rise detection device according to any one of claims 1-7 is used to detect the temperature rise of the power device (010) under test, and the detection method includes: The measuring mirror (310) is fixed to the power device under test (010). When the detection device is turned on, the light emitted by the light source (100) is split into two beams by the beam splitter group (200). The two beams are reflected by the measuring mirror (310) and the reference mirror (320) respectively. The optical path system is adjusted so that the two reflected beams produce Michelson interference. The signal processing system acquires and processes the interference fringe signal to obtain the displacement of the measuring mirror (310) and infers the temperature rise of the power device under test (010).

9. The power device temperature rise detection method according to claim 8, characterized in that, The signal processing system includes an oscilloscope, and the detection method includes: adjusting the optical path system until the signal displayed on the oscilloscope is an ideal circle before starting the detection.

10. A computer-readable storage medium storing a computer program / instructions and a bit stream thereon, characterized in that, When the computer program / instruction is executed by the processor, it acquires the signal data processed by the signal processing circuit (500) in claim 2 and calculates the temperature rise of the power device under test (010) to generate the bit stream.

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