Design Of The Air-cooling Experimental System For Power Semiconductor Devices

With the development in electronic industry, the power semiconductor device is developing toward the direction of miniaturization, compact and high performance. It increases the heat flux and surface temperature of single device. Thus it is of great significance to research heat dissipation of power semiconductor device. It is difficult to obtain accurate performance index of semiconductor device merely using the theoretical calculation method. We need also to investigate heat dissipation of semiconductor device by experiment. This paper designs a set of experimental platform for power semiconductor radiator cooling system with high automation, accurate measurement and simple operation. The platform includes type selection of fan, the designation of wind tunnel, air heater, measurement system and automatic control system.According to the characteristics of the radiator, the wind tunnel including former stable section, testing section and back stable section is designed and calculated, in which the testing section can be rotated. Sensors, air heater, fan and frequency converter are selected and installed reasonably to meet the test requirements.Automatic control system with is designed to control experimental platform, and two operation models of automatic and manual are set. The inlet air temperature in testing section and wind speed inside wind tunnel is controlled automatically and the parameters are adjusted automatically. The PLC of S7-200 series of SIEMENS Company is selected as slave computer of the testing platform and the STEP 7 micro/WIN programming software is used to create corresponding projects. The industrial personal computer(IPC) as upper computer connected slave computer with programming cable. The Kingview installed in IPC controls the start-stop of experiment platform, and controls and adjusts the fan frequency and heater power by using PID. All kinds of parametric curves and data are real-time displayed and stored by software. The historical data are inquired and analyzed intelligently. The software has extended function so as to adapt to the higher designation requirements in the future.At last, the experimental platform is debugged. By analyzing the PLC interference problem occurring in the debugging process,the solution is presented in this paper. Take heat pipe radiator for example, this paper has established the theoretical model of heat transfer performance and analyzed the heat transfer resistance of heat pipe and fin according to the basic theory of heat transfer, This lays a theoretical foundation for the radiator experiment. The thermal resistance and flow resistance of typical profiles radiator and heat pipe radiator are tested by using experimental platform. The results and the conclusions in relevant literatures are in close agreement that verify the accuracy and rationality of the proposed designation.