Abstract : This paper provides a detailed analysis of the interference forms that may occur in the practical use of variable frequency speed control systems, proposes corresponding suppression measures for different interference forms, and analyzes several common faults and their solutions. Keywords : Variable frequency drive; Suppression measures; Fault analysis 0 Introduction Variable frequency drives (VFDs) are an organic combination of computer technology, modern control technology, and network technology. They have advantages such as wide speed range, high speed accuracy, fast dynamic response, high operating efficiency, and significant energy-saving effects. They have become one of the main means to transform traditional industries, improve industrial processes, enhance the automation level of production processes, and promote technological progress. They are widely used in the control of machine tools, machinery manufacturing, and assembly lines. 1 Anti-interference measures for VFD control loops VFDs themselves are sources of harmonic interference, while their surrounding control loops are low-energy, weak-signal loops, which are easily affected by interference from other devices, causing the VFD itself and its surrounding environment to malfunction. Therefore, anti-interference measures must be taken for the control loops of VFDs during installation and use. [b]1.1 Several Common Types of Interference and Anti-interference Measures 1.1.1 Electrostatic Coupling Interference[/b] Refers to the electromotive force generated in the cable due to electrostatic coupling between the control cable and the surrounding electrical circuit. [b][align=center]For details, please click: Inverter Anti-interference Measures and Common Fault Analysis[/align][/b]