Research On Key Technology Of Insulating Ferrite Core Transformer High Voltage Power Supply

Electron irradiation accelerators have been widely used in fields of industry,agriculture,health care and environmental protection.Insulating core transformer accelerator is an important kind of electron irradiation accelerators,the key device of which is insulating core transformer high voltage power supply.Its output voltage determines the output voltage level of accelerator,and its working performance affects the quality of irradiation processing.Therefore,the research of insulating core transformer high voltage power supply is of great significance.Based on the principle of conventional insulating iron core transformer high voltage power supply,the scheme of a new high voltage power supply is raised,namely insulating ferrite core transformer high voltage power supply.Its main features are as follows: first,ferrite is chosen as magnetic material to increase the allowable working frequency and reduce the volume of the power supply;second,polyimide film is chosen as insulating layer material to reduce the thickness of the insulating layer and the flux leakage of the power supply;third,square wave is chosen as input power to reduce the volume of the input power and improve the control precision of the output voltage;fourth,four core columns structure is chosen as magnetic core structure to improve the space utilization rate and output voltage of the power supply.Based on the above features,the design and preliminary experiment of an insulating ferrite core transformer high voltage power supply with basic index of 400 kV/50 mA is carried out.First,the main body design of the high voltage power supply is accomplished,including the design of magnetic core,insulating layer and coil.According to the designed core structure,its magnetic circuit model is established and analyzed.Second,analysis and design of the accessory structure of the high voltage power supply is completed,including the design of grading ring and electrode cap,the electric field analysis of the power supply,the analysis of the flux leakage compensation structure,the analysis of the rectifier circuit and the design of the mechanical structure.Then,the magnetic field analysis and the parameter optimization of the high voltage power supply are accomplished with the help of finite element software.Finally,a preliminary experimental model is built,and the number of turns of the secondary coil is optimized.Under atmosphere the no-load experiment of the model is carried out.The results show that the measured data of the experimental model approximately agrees with the simulation result,which meets the design requirement.Still,there are some problems that need to be solved in the following study.