THE DISCUSSION ON POWER FACTOR DEFINITION IN SINGLE PHASE SYSTEM WITH ARBITRARY WAVEFORM
LING Zhi-bin, DENG Chao-ping, YE Peng-sheng (Electric Engineering Dept., School of Electronic Information & Electric Engineering, Shanghai Jiao Tong University, Shanghai 200030,China)
In this paper, a frequency domain description of similarity between voltage waveform and current waveform was achieved in infinite dimensions real vector space. Then a new kind of definition formula of power factor was proposed, which was suitable under arbitrary waveform voltage in single phase system. In this definition, power factor was defined as the product of virtual value similarity factor lRMS and phase similarity factor lj. According to new definition, under voltage with arbitrary waveform, power factor of linear resistor was identical with 1, power factors of inductor and capacitor were identical with 0, and power factors of other kinds of load were in (0,1). The error between conventional definition and new definition was analyzed also.