Abstract: This paper analyzes the energy-saving principle of variable frequency speed regulation for feedwater pumps; it also conducts in-depth research on problems such as cavitation and balance disc wear after the boiler feedwater pump is controlled by a frequency converter, and proposes solutions. Keywords: feed water pump, variable frequency speed control, boiler cavitation, erosion, balance disc wear [b][align=center]Effect of the Technique of Variable Frequency Governing on Safety Operation of Boiler Feed Water Pump DU Zhao hui1 XU Pei yao2 （1. Power Station, Baoding Petrochemical Plant of SINOPEC Baoding, Hebei 071051）[/align][/b] Abstract : The energy-saving principle of variable frequency governing technique for the boiler feed water pump is discussed. Problems such as cavitation erosion and the galling of balance disc following with the variable frequency governing technique in the boiler feed water pump are studied. Finally, a suitable solution is provided. Keywords : feed water pump, variable frequency governing, boiler, cavitation erosion, galling of balance disc In 1997, the power plant of Baoding Petrochemical Plant converted 2 forced draft fans and 2 induced draft fans to variable frequency control. After several years of operation, the energy-saving effect was significant and the equipment operation was good. Therefore, in 2003, the model DG46 50 ×12 The No. 2 feedwater pump was replaced with an IPF160 K frequency converter manufactured by Sanken Corporation of Japan. After running for a period of time, the energy-saving effect was obvious, but problems such as mild cavitation of the feedwater pump and severe wear of the balance disc occurred one time, causing the feedwater pump to trip, shortening the operating cycle of the No. 2 feedwater pump, affecting the safe operation of the equipment and the safe production of the entire plant, and increasing maintenance costs. After research, the power plant modified several inappropriate parameters of the frequency converter and replaced the balance disc of the feedwater pump, which solved the problem. 1. Analysis of the energy-saving principle of variable frequency speed regulation Since many cogeneration units are based on heat demand, the load fluctuates greatly with the seasons. Moreover, the peak shaving efforts of thermal power units have increased, and the load variation range of the units is also very large. These situations require real-time adjustment of the feedwater pump flow rate. At present, the method of adjusting the feedwater pump flow rate is mostly to install a valve at the outlet end for throttling regulation. Its essence is to change the flow loss in the outlet pipeline, change the characteristic curve of the pipeline, and thus change the operating point of the pump. Because this regulation method only adjusts the excess flow through the regulating valve, while the motor's output power remains largely unchanged, a significant amount of electrical energy is wasted. The principle of speed regulation and energy saving can be explained from the following two aspects: [b][align=center]For details, please click: The Impact of Variable Frequency Speed ​​Regulation Technology on the Safe Operation of Boiler Feed Pumps[/align][/b]