Abstract : Starting from the generation of frequency converter interference, this paper focuses on reducing the impact of interference on surrounding equipment, and proposes specific methods to be adopted from the perspectives of interference propagation path, preventive measures during the installation of frequency converter, and different interference sources and paths. Keywords : frequency converter, propagation path, anti-interference measures 1 Overview The positioning car, pusher, and vibrating feeder of the Huanghua Port Phase II tipper system are driven by Siemens frequency converters. In actual work, it has significant energy-saving effect, precise control, and simple maintenance. However, due to the special working mode of frequency converter, the interference brought by field communication, photoelectric relays, proximity switches, sensors, encoders, programmable controllers, etc. is becoming increasingly important. Some even affect life safety. Therefore, based on the actual situation on site and the causes of interference, the following anti-interference measures are adopted. The actual application effect is relatively ideal. 2 Generation and types of frequency converter interference (1) Frequency converter is a power supply in a special sense. It is mainly composed of three parts: rectification part, inverter part, and capacitor, that is, converting AC power with fixed voltage and frequency into AC power with variable voltage and frequency. The motor is controlled by a variable speed. The rectifier section converts AC to DC. The inverter section uses 6 transistors (IGBTs) to convert DC to AC with variable frequency and voltage. Due to the high-speed switching of these 6 transistors, switching interference is generated. At the same time, during the high-speed switching process, the stray capacitance (C) between the inverter, cable, motor and ground is used to release interference current (i) to the ground. The magnitude of this interference current is as follows: i=C＊du/dt Therefore, it is related to the stray capacitance and &ddt (transistor switching speed). (2) The interference generated by the inverter is transmitted from the power supply side to the motor side through the main circuit wires. Its propagation path is diverse. It can be roughly divided into three paths: conduction, induction and radiation interference. [b][align=center]For details, please click: Anti-interference measures of inverter for Huanghua Port Phase II tipper system[/align][/b]