This paper investigates the economic benefits for coal-fired power plants by implementing Variable Speed Drives (VSDs) for electrical auxiliary systems, including annual energy savings, net generation capacity improvement, and increased active power output capability. In this paper, both working principle and energy saving mechanisms for auxiliary pumps and fans have been analyzed first. Based on a representative coal-fired power plant, annual energy savings and net generation capacity improvement from several commonly used control methods have been calculated and compared, thereby demonstrating the advantages of VSD use. In addition, plant active power capability improvement has been introduced as another important benefit of VSD, which can be realized by power factor improvement at medium voltage bus bars. Detailed calculations have been given to verify the benefit. Finally, capability improvements under different scenarios have been compared to further clarify this issue.
Active power capability Coal-fired power plant Economical benefit Electrical auxiliary system Energy efficiency Energy savings Net generation capacity Power factor Pumps & fans Variable speed drives VSD
Yao Chen Jiuping Pan Lars Gertmar Richard W Vesel
ABB China Corporate Research Center, Universal plaza, 10 Jiuxianqiao Lu, Chaoyang district, Beijing, ABB US Corporate Research Center, 940 Main Campus Drive, Raleigh, NC, 27606, USA ABB Sweden Corporate Research Center, Forskargrand 7, S - 72178, Sweden ABB Inc, Power Generation North America, 29801 Euclid Avenue, Wickliffe, OH, 44092, USA