Electromagnetic compatibility standards of switching power supply at home and abroad
Electromagnetic compatibility refers to the ability of a device or system to work normally in its electromagnetic environment without causing unbearable electromagnetic interference to anything in the environment.
It is impossible to completely eliminate the electromagnetic interference of equipment and be insensitive to all external electromagnetic interference signals. Only by systematically formulating the standards of the allowable electromagnetic interference and the ability to resist electromagnetic interference between equipment can the requirements of electromagnetic compatibility between electrical equipment and systems be met. A large number of electromagnetic compatibility standards at home and abroad set constraints for devices in the system to achieve electromagnetic compatibility with each other.
The Special Committee on International Radio Interference (cispr) is an electromagnetic compatibility standardization organization under the International Electrotechnical Commission (iec). As early as 1934, it began to study the emc standard, with six chapters. Among them, the Sixth Sub-committee (scc) is mainly responsible for formulating standards for interference measurement receivers and measurement methods. Cispr16 "specifications for radio disturbance and immunity measuring apparatus" gives detailed requirements for the performance of EMC measurement receivers, auxiliary equipment and calibration methods. Cispr17 "Measurement of Suppression Characteristics of Radio Interference Filters and Suppression Components" has formulated the measurement method of filters. Cispr22 "Limits and Measurement Methods of Radio Interference of Information Technology Equipment" stipulates the limits of electromagnetic interference generated by information technology equipment in the frequency range of 0.15 ~ 1000 MHz. Cispr24 "Limits and Measurement Methods of Immunity of Information Technology Equipment" stipulates the anti-jamming performance requirements of information technology equipment for external interference signals in time domain and frequency domain. Among them, cispr16, cispr22 and cispr24 constitute the EMC test content and test method requirements of information technology equipment, including communication switching power supply equipment, which are the most basic requirements for EMC design of communication switching power supply at present.
Iec has recently published a large number of basic electromagnetic compatibility standards, the most representative of which is iec61000 series standards. It specifies the electromagnetic compatibility requirements for lightning strike, surge, electrostatic discharge (esd), electrical fast transient (eft), current harmonics, voltage sag, voltage transient and short-term interruption, voltage fluctuation and flicker, radiated electromagnetic field, immunity to conducted interference caused by RF electromagnetic field, conducted interference and radiated interference.
In addition, fcc15 formulated by the Federal Council of the United States, vde08712a1, vde08712a2 and vde0878 formulated by the German Institute of Electrical Engineers all require electromagnetic compatibility of communication equipment.
China's research on electromagnetic compatibility standards is relatively late. The main methods adopted are introduction, digestion and absorption, and foreign things serve China is the main method for formulating domestic electromagnetic compatibility standards. In 1998, according to cispr22, iec61000 series standards and ituto.41 standards, the Ministry of Information Industry formulated yd/t9831998 "Limits and Measurement Methods of Electromagnetic Compatibility of Communication Power Supply Equipment", which specified in detail the specific test items, requirements and test methods of electromagnetic compatibility of communication power supply equipment, including communication switching power supply, and defined the design objectives for electromagnetic compatibility inspection, reaching the standard and passing the network inspection.
