Abstract: A new type of heat pipe radiator is compared with the traditional heat pipe radiator. Its performance tests show that the thermal resistance of this radiator is 0.064℃/W, and its main performance indicators are superior to similar heat pipe radiators at home and abroad. This demonstrates that the self-cooling heat dissipation capacity has reached a high level, which greatly promotes the application of this technology in China. Keywords: horizontal placement; increased spacing; wave suppression; self-cooling; introduction Thyristor self-cooling heat pipe radiators are an advanced and efficient heat dissipation device developed in recent decades and applied in power electronic equipment. To advance the practical application of this advanced technology, numerous scholars have designed and developed self-cooling heat pipe radiators with various structures, which are widely used in engineering. Self-cooling heat pipe radiators have been used for over a decade for thyristors with currents below 800A. However, the high thermal resistance of these radiators makes them unsuitable for cooling thyristors with currents above 800A. Traditional heat pipe radiators are heavy, and the use of expensive copper and aluminum materials further increases their cost. As power electronic equipment continues to evolve towards lighter and more convenient designs, there is a growing demand for smaller and lighter devices. The aim is to replace existing radiators with self-cooling heat pipes to reduce costs. Therefore, improving the structure of existing heat pipe radiators and developing a high-performance heat pipe radiator is of great significance. 1. Structure of the New Type of Heat Pipe Radiator 1.1 Design Conditions for a Thyristor-Based Self-Cooling Heat Pipe Radiator: Rated current 1000A, maximum allowable thyristor core temperature 120℃, maximum ambient temperature Ta=40℃, radiator surface temperature Tr=85℃, diameter of the radiator-thyristor contact surface 63mm. Radiator heat dissipation power P=700W. Radiator thermal resistance Rx is calculated using the following formula: Rx=（Tr-Ta）/P=0.064℃/W. 1.2 Structure of the Heat Pipe Radiator 1.2.1 Increasing the Spacing of Heat Sinks: Increasing the spacing of the heat sink fins to 16mm increases airflow and reduces the thermal resistance of the heat pipe radiator. 1.2.2 Horizontal Placement of Heat Sinks to Enhance Heat Transfer: Following the principle of addressing the high thermal resistance, the radiator is placed horizontally, allowing for vertical and direct airflow. 1.2.3 Heatsink Suppression To increase the contact area between the air and the heatsink, fins are suppressed (as shown in Figure 1), thereby improving heat dissipation capacity and reducing the thermal resistance of the heat pipe radiator. Based on the above conditions, this high-performance self-cooling heat pipe radiator was designed and developed. Figure 1: Heatsink of the new heat pipe radiator Figure 2: Test of the new heat pipe radiator Figure 2 Performance test of the self-cooling heat pipe radiator To verify the performance of the designed and developed radiator, performance tests were conducted. In addition, a heat pipe radiator with basically the same dimensions but tilted at 5.75°, without fin suppression and with a fin spacing of 8 mm (i.e., a traditional radiator) was also fabricated for comparison. The single-sided radiator consists of nine φ16 mm heat pipes arranged in a row. The radiator's shape is shown in Figure 2. Thyristors are used to heat the radiator. The heating system consists of a voltage regulator, a voltage stabilizer, and thyristors. The testing instruments consist of a thermometer, an ammeter, and a voltmeter. The thermometer's thermocouple is made of copper wire with a diameter of 0.26 mm. Location of Radiator Temperature Measurement Reference Points: Location 1: The middle of the second front heatsink, 2 cm from the top edge of the heatsink. Location 2: The middle of the second rear heatsink, 2 cm from the top edge of the heatsink. Location 3: Thyristor cathode housing. Test Time: 40 minutes of power-on. Test Equipment: Conductive busbar, partition, plastic bracket, etc. Ambient Temperature: 17℃. Test Current: 1000A. Installation Method: Double-sided. Cooling Method: Self-cooling. 3. Comparison of Test Results The two types of heatsinks were tested under completely identical test conditions. Table 1: Comparison of Heat Dissipation Data between the New Heat Pipe Heatsink and the Traditional Heat Pipe Heatsink. Table 4. Material Saving In today's world of extreme energy and mineral shortages, material saving has become a top priority. The new heat pipe heatsink saves approximately 40% more aluminum plate than the traditional heat pipe heatsink. Its performance is also superior to that of the traditional heat pipe heatsink. References: [1] Liu Jianmin, ed. Heat and mass transfer principle and its application analysis in electric power technology: First edition. Beijing. China Electric Power Press. [2] Zhuang Jun and Zhang Hong, ed. Heat pipe technology and its engineering application: First edition. Beijing. Chemical Industry Press Industrial Equipment and Information Engineering Publishing Center. [3] (Japan) Ikeda Yoshio et al., ed., Shang Gaisong, Li Pengling, translator. Practical heat pipe technology: First edition. Beijing. Chemical Industry Press. [4] (Soviet Union) Ivanovskii, MN et al., ed. Physical principle of heat pipe: First edition. Beijing. China Petrochemical Press. [5] (USA) Chi, SW, ed. Heat management theory and practice: First edition. Beijing. Science Press. About the author: Sui Song (1982-), male, from Anshan, Liaoning, with a bachelor's degree, is mainly engaged in the design and development of heat pipe radiators (E-mail: [email protected]).