Abstract: To meet the teaching requirements of the dedicated course "Power Electronics Technology Experiment", our school has independently developed a power electronics technology experimental device. Drawing on the advantages of commercially available products and referencing the latest research results of our school, we have developed a new generation of power electronics technology experimental devices. The overall concept is to adopt a hanging box structure, ensuring compatibility with the manufacturer's main control panel power supply equipment as much as possible. This allows for direct use with minimal or no modification to the manufacturer's experimental platform. Furthermore, the self-made device balances practicality, fundamentality, advanced technology, ease of maintenance, and expandability, seeking multiple innovative solutions. It also possesses a complete set of technical drawings and component purchasing channels, ensuring manufacturability. Keywords: Power electronics; Experimental device; Experimental equipment "Power Electronics Technology" is an important professional technical foundation course for Electrical Engineering and Automation majors. To emphasize the cultivation of practical skills and establish an experimental teaching philosophy oriented towards industry-specific engineering capabilities, reflecting the principles of "emphasizing quality, comprehensiveness, and innovation", our school has established a separate course and separate assessment for power electronics technology experiments. We found that commercially available products could not meet the teaching requirements of a standalone course. Therefore, we decided to reform our own equipment, starting with the experimental setup. The main reason was the lack of test points related to the branch currents of the control and main circuits, limiting us to open-loop control only, and the absence of basic power electronic converter experimental enclosures. Single-ended forward and single-ended flyback circuits are fundamental isolated power electronic converter topologies and are a key focus in classroom teaching. However, renowned manufacturers of power electronics experimental teaching instruments did not offer such enclosures. Therefore, we believed it was necessary to independently develop experimental devices, incorporating the advantages of manufacturer equipment and our own latest research findings to develop a new generation of power electronics experimental equipment. Ultimately, we developed seven types of experimental enclosures. 1. Design Philosophy of Self-Made Equipment The overall approach to self-made equipment at our school was to ensure practicality, fundamental knowledge, advanced technology, ease of maintenance, and expandability. We sought multiple innovative solutions and developed a complete set of technical drawings, ensuring manufacturability. In terms of experimental content, we emphasized the systematic nature of experimental teaching and the rational setting of observation points, fully considering the experimental research content of the main and control circuits. The experimental equipment can simultaneously observe and study the main circuit content, control circuit content and closed-loop feedback content. [sup][5][/sup] . 2 Specific implementation plan (1) Determine the key points of the experimental box development The course content of "Power Electronics Technology" is mainly divided into two parts: the traditional power electronics part represented by thyristors and the modern power electronics part represented by fully controlled devices. Now, modern power electronics technology with high frequency conversion as the main feature has gradually become the core technology, and new topologies and control methods have become the most active research directions in electrical engineering. In order to adapt to this development trend, high frequency power electronics has become the key content of our school's experimental practice teaching. Therefore, the experimental boxes made by our school, except for the basic phase-controlled rectification part, are all made by various high frequency conversion DC-DC converters. (2) Compatibility and safety implementation plan In order to be compatible with the main control panel power supply equipment of the manufacturer, the power supply box we developed is used as the second-level power supply equipment. This will eliminate the use of secondary power supply in the box, avoid the conversion of high voltage in the box, and the input voltage is also low voltage, which completely solves the safety problem. This solves the problem that mandatory safety certification only exists in one type of equipment: power supply boxes. To further address safety issues, we used a safety-certified switching power supply as the power source when developing the power supply box. However, due to the high noise voltage amplitude of the switching power supply, which would overwhelm the normal sampling signal, we used a common-mode noise suppression circuit composed of a magnetic ring and an RC low-pass filter to suppress high-frequency noise. This technology has been granted a utility model patent. (3) Phase-controlled rectification implementation scheme In the design of the drive circuit, different wiring can change the topology of different phase-controlled rectifier main circuits, so that one box can systematically complete the performance study of two different main circuits. The trigger angle changes continuously throughout the phase shift range, allowing for detailed observation and control of all relevant characteristics. The types of experiments that the box can complete include experimental research on three-phase half-wave controlled rectifier circuits and their trigger circuits, and experimental research on three-phase bridge fully controlled rectifier circuits and their trigger circuits. The experimental content that can be completed in each experimental category includes: ① Comprehensive, accurate and detailed study of the operation of the main circuit and trigger circuit; ② Comparison of the operation of different load characteristics; ③ Study of external characteristics; ④ Comparison of the similarities and differences in the operation of different topologies. (4) Overall implementation plan of DC-DC converter The implementation plan of DC-DC converter is to ensure that the main circuit, control circuit and closed-loop feedback are reflected in the panel lead design. While ensuring basic experimental research, it is extended to comprehensive improvement research and design experimental research. The experimental categories that can be completed are: ① Experimental research on the main circuit and control circuit of BUCK converter; ② Experimental research on the main circuit and control circuit of BOOST converter; ③ Experimental research on the main circuit and control circuit of single-ended forward converter; ④ Experimental research on the main circuit and control circuit of single-ended flyback converter. Its experimental research includes the following levels. ① Basic experimental research, including detailed observation and research on the main circuit, control circuit and closed-loop feedback, and comprehensive analysis. ② Improvement experiment research, including changing the control frequency to observe the conversion between the continuous and discontinuous points of the current and the circuit performance experiment (patent granted [sup][7][/sup]), experiments to study the role of absorption circuit and buffer circuit, and experiments to study the performance changes of the main circuit by changing the transformer turns ratio parameters of key components. ③ Design experiment research is to study the performance changes of key components such as inductance parameters and transformer parameters. As shown in Figure 1, the main control panel power supply system purchased from the manufacturer powers the self-made DC power supply box, and then the box powers the self-made BUCK converter experimental box. The BUCK converter experimental box panel contains the main circuit experiment content, the control circuit drive circuit experiment content, and the closed-loop feedback content. Its load is the self-made box load. 3 Features of the self-made experimental box (1) The experimental module can not only conduct verification experiments, but also conduct certain research experiments. For example, the experimental module can change the frequency of the PWM wave signal by changing the oscillation frequency of the control circuit, thereby changing the critical continuity point of the current. Thus, without changing the hardware circuit (main circuit), the conversion between the continuous current (CCM) and discontinuous current (DCM) working conditions can be observed, which is conducive to the comprehensive analysis of circuit performance and in-depth understanding of the circuit working principle. (2) The experimental module can not only conduct open-loop experiments of converters, but also conduct closed-loop experiments. In addition to the main circuit experiment function of commercially available power electronics experimental equipment, this module also has control circuit experiments that it cannot complete. (3) The detection points of key voltage waveforms in the control circuit and the detection points of main branch current waveforms in the main circuit have been added to simultaneously observe and study the state of the main circuit, control circuit and closed-loop feedback. (4) The built-in impedance technology is adopted at the signal detection points, which does not affect the observation of the signal and can prevent students from making mistakes in wiring or operation, thus improving the reliability of the experimental equipment. (5) The reasonable design of the experimental hanging box wiring layout greatly improves its expansion performance. (6) The experimental platform uses a safety-certified switching power supply, which can ensure the safety of the experimental equipment. 4 Conclusion Our school's self-made power electronics experimental equipment has been in operation for more than two years and has been open to students majoring in electrical engineering and automation, benefiting nearly a thousand people. Experiments can be completed in three modes: planned arrangement, main, group reservation and individual student reservation. Undergraduate experimental teaching in other universities has also benefited from this and has been highly praised. Practice shows that the self-made experimental device has played a good role in cultivating students' practical ability. References: [1] Yu Yongxiang. Overview of the application of power electronics technology [J]. Beijing: New Technology and New Process, 2000 (10): 12 [2] Xu Xiangmin, Lü Hualin, You Fangmin et al. Strengthen guidance, rely on disciplines, and build an innovative platform for in-class and extracurricular practice [J]. Xi'an: China Electronic Education 2006 (3): 33-37 [3] Huang Daming, Qin Gangnian, Wen Bing et al. Research and practice on independent professional experimental courses [J]. Shanghai: Laboratory Research and Exploration, 2007 (11): 85-87 [4] Ren Zhengyi, Wang Dong. Strive to achieve "great engineering and great science" [J]. Shanghai: Laboratory Research and Exploration, 2007(11):68-72 [5] Huang Daming, Qin Gangnian, Wen Bing et al. Research and practice on independent course design for professional experiments [J]. Shanghai: Laboratory Research and Exploration, 2007(11):85-87 For details, please click: Development of a new generation of power electronics experimental device