Abstract : This paper introduces the principle of variable frequency drive (VFD) speed regulation and energy saving and its application in Kailuan Power Plant. Operational and testing results show that the power plant's adoption of low-voltage VFDs for speed regulation and energy saving of equipment such as pulverized coal exhaust fans has significant energy-saving effects, while also reducing equipment wear and environmental pollution. Keywords : VFD; power plant; pulverized coal exhaust fan Kailuan Power Plant is a self-owned power plant of Kailuan Group, with a current installed capacity of 3x25 MW, operating with four boilers and three turbines. It is a medium-temperature, medium-pressure cogeneration coal-fired unit. All turbine generator units were manufactured by Wuhan Turbine Generator Works. Unit #2 was commissioned in June 1992, Unit #1 in June 1993, and Unit #3 was an expansion project, commissioned in March 2004. Kailuan Power Plant supplies electricity to Kailuan Group, but cannot fully meet the group's electricity needs; purchased electricity accounts for more than 20% of the total electricity consumption annually. With the formation of China's frequency converter technology market, frequency converter technology has been widely applied in industries such as power, chemical, and metallurgy, achieving excellent energy-saving effects, especially low-voltage frequency converter technology, which is more mature. Therefore, Kailuan Power Plant adopted frequency converter technology to first upgrade the drive power supply of the pulverized coal exhaust fan, seeking ways and methods to save energy and reduce consumption to improve the company's competitiveness. 1. Frequency Converter Speed ​​Regulation and Energy Saving Principle The speed n of the asynchronous motor is related to the frequency f, the motor slip s, and the number of pole pairs P of the motor as follows: [b][align=center]For details, please click: Application of Frequency Converters in Kailuan Power Plant[/align][/b]