Emc Research On Controller Of Digital Frequency Conversion Generator

With the characteristics of high efficiency, environmental friendly and portability, Digital frequency conversion generator is widely used as an important stand-by power supply in people’s daily life. Digital frequency conversion generator controller, working as the core of generator system, has completed the power supplies’rectifier-inverter, and also the speed control of generator. So the controller includes power inverter circuit and high frequency digital circuit, a combination of weak and power electricity, making the electromagnetic environment complicated, bringing forward high requirements towards the controller’stability, reliability and safety. At the same time, various countries in the world impose strict limitations on the EMC of products that only qualified products can be allowed into the market. Thus, it is of utmost significance to make research and solve the problems of EMC in controllers.Firstly, this paper makes brief introduction to the controller’s overall hardware configuration and control strategy, highlighting the analysis of the controller’ electromagnetic environment.Secondly, this paper lays emphasis on the analysis of transmission EMI produced by the controller power inverter circuit, whose equivalent model was established. Methods to decrease the EMI interference was discussed based on the time domain and frequent domain analysis of the equivalent model and Main filter is also designed.Besides, this paper has also carried out the PCB’s EMC design. Firstly, the cause of EMI on PCB and the methods to decrease were stated. Then the crosstalk between high frequency signal lines was simulated, and the effects of parameters on crosstalk were discussed. At last, the EMC design of PCB was finished on the basis of interference immunity design of core circuits.Finally, based on the simulation analysis and design, the controller’s prototype was made, and the noise of controller and generator was tested, whose results indicate that the controller has good EMC performance.