Research On Test Method Of Electromagnetic Compatibility Conduction Characteristics Of Power Electronic Devices

With the development of power devices toward high frequency,the problem of conductive electromagnetic interference generated by a large number of power electronic devices has become increasingly serious.Especially in high-power equipment,the voltage and current transients caused by the high-speed switching process of power devices have brought serious electromagnetic interference to power electronic devices,which has become an important bottleneck for the advancement of power electronics technology.Based on this,this paper focuses on the related issues of the electromagnetic compatibility conduction characteristics test method of power electronic devices,the main work is as follows:(1)The research status of relevant standards of electromagnetic compatibility at home and abroad is expounded and compared.The problems of interference sources,transmission paths and sensitive equipment of power electronic systems are analyzed,and related test methods are researched.In addition,the test sites and test equipment required for EMC related test items are mainly studied.(2)The principle and standard of conducted immunity test are compared,analyzed and studied,and a conductive immunity test method based on electromagnetic clamp injection is proposed.Considering that the switching power supply is a typical power electronic device,this paper takes the switching power supply(model FDPS-50A)as the research object.Under different working conditions,the electromagnetic immunity clamp injection method is used to conduct the conducted immunity test.The electromagnetic immunity of the model switching power supply verifies the effectiveness of this test method.This test method not only makes it better suited to the availability of test equipment,but also makes the test operation more convenient.This method is universal.So it can be used in the testing of other systems or components.It has certain practical significance for the predictive analysis of electromagnetic immunity of power electronic equipment.(3)When the electrical and electronic equipment is not working,some interference signals are still transmitted to the low-voltage output side through the coupling path on the high-voltage input side,and the strength of the output-side interference is described by the high-low-voltage coupling attenuation characteristics.At present,there is no test method for coupling attenuation characteristics of power electronic devices.This paper presents a general coupling attenuation test method.Through the research and analysis of the coupling attenuation test principle and test method,the coupling attenuation test was carried out with the switching power supply as the research object,and the experimental results under different working conditions were measured.By analyzing the above test results,the test curves of high and low voltage coupling attenuation characteristics are obtained,and the correctness and versatility of the method are verified,which can be used in the testing of other systems or equipment.The method improves the electromagnetic compatibility testing technology and compensates for its gap in the field of coupling attenuation testing,which helps engineers to better understand the electrical characteristics of electrical and electronic equipment,test the high and low voltage isolation level inside the equipment,and it is very helpful to reduce the specific problems of EMC.