Single phase EMI filter is a device specially designed to suppress electromagnetic interference (EMI) in single phase circuits. It is mainly composed of inductors, capacitors and other components, which can effectively filter out high frequency noise and interference signals on the power line, thereby improving the electromagnetic compatibility of the circuit. Single phase EMI filter has the characteristics of small size, light weight and easy installation, and is widely used in communication systems, power systems, household appliances and other fields. By reducing electromagnetic interference, single phase EMI filter can ensure the normal operation of equipment and the accuracy of data, and improve the stability and reliability of the entire system.