Abstract : This paper provides an in-depth introduction to the application of frequency converters (VDCs) in thermal power units, analyzing their energy-saving principles, calculation methods, economic benefits, usage effects, and potential problems. It also points out the precautions for applying VDCs, offering valuable reference and promotion for the VDC retrofitting of similar units. Keywords : Thermal power unit; Frequency converter; Energy saving 0 Introduction With the rapid development of power and electronic technologies and the increasing emphasis placed on energy conservation and consumption reduction by enterprises, frequency conversion control technology has become basically mature, leading to a surge in VDC retrofitting in many thermal power plants. Some thermal power units have successively installed VDC devices, retrofitting large auxiliary equipment such as condensate pumps, forced draft fans, and induced draft fans. Analysis of the VDC retrofitting effects on units below 200 MW shows that the system has good stability and significantly improves the adjustment quality of process parameters. Therefore, VDC energy-saving technology is gradually being promoted, and its excellent energy-saving effect and stable performance are attracting increasing attention. 1. Variable Frequency Drive Energy-Saving Principle and Comparison with Other Energy-Saving Technologies [b][align=center]For details, please click: Application Research of Variable Frequency Drives in Thermal Power Units[/align][/b]