Research On Thermal Design Of Millimeter Wave Power Module

Millimeter wave power module(MMPM)is a new type of microwave power amplifier working in millimeter wave.It is mainly composed of three major components: millimeter wave miniaturized traveling wave tube,solid state amplifier and electronic power conditioner.It has the advantages of small size,light weight,high efficiency,high frequency,wide frequency band,etc.With the improvement of the miniaturization of MMPM,excessive temperature and uneven heat distribution have become key factors restricting its reliability.Based on this,the thermal design research of MMPM is of great significance for improving the reliability of MMPM.The main work of this paper is as follows:1.The characteristics and heat consumption of MMPM are studied,and the theoretical basis,software tools and overall design idea of thermal simulation optimization are determined.2.A thermal optimization design method without changing the main structure of TWT is proposed.Firstly,according to the structure and power distribution of TWT amplifier,the thermal analysis simulation model is established.Then,the thermal distribution of the existing structure is obtained by software simulation,and the safety assessment of the heat consumption is carried out based on the working principle of TWT.On this basis,an optimization design method without changing the main structure of TWT is put forward: the spiral structure is optimized by adding embedded heat conduction sheet,which eliminates the problem of local overheating of spiral;the overall temperature rise is reduced by optimizing the fin clearance of water-cooled plate.Furthermore,the effectiveness of the optimization design method is verified by simulation and experiment.This method has good thermal optimization effect,solves the problem of local overheating,reduces the overall temperature rise,and avoids the redesign of TWT with complex structure.3.Thermal analysis and optimization design of integrated power supply.Aiming at the heating problem of the magnetic components in the integrated power supply,the electromagnetic simulation and the electromagnetic thermal coupling simulation analysis of the PCB planar inductor are emphasized.The influence of the air gap and the position of the winding on the winding loss is studied,which provides the basis for the optimization design of the resonant inductor.According to the integrated power supply circuit,the thermal simulation model of the integrated power supply is established,and the thermal analysis and optimization design of the integrated power supply are carried out.By connecting the integrated power supply with the simulated load,the effectiveness of the thermal analysis and optimization design method of the integrated power supply is verified.4.Thermal analysis and optimization design of MMPM.The high temperature and uneven heat distribution of MMPM seriously affect the reliability of MMPM.Based on this,the thermal analysis of MMPM is carried out.Combined with the results of thermal analysis,the water-cooling method is selected to make MMPM work at a suitable temperature.The validity of MMPM thermal analysis and optimization design method is verified by the temperature test of MMPM prototype.