Li Hongyu, Zhuo Fang, Wu Longhui, Lei Wanjun, Wang Zhao'an
(School of Electrical Engineering, Xi'an Jiaotong University, Xi'an 710049, China)
Abstract:
The performance of active power filter adopting traditional current detection algorithm is
degraded. In contrast with traditional current detection algorithm, a novel current
detection algorithm, based on time domain for a three-phase shunt active power filter to
eliminate harmonics and£¯or correct power-factor and£¯or balance the nonlinear
unbalanced loads, is presented. The physical implication of every component and the effect
on the capacity of active power filter are explained in detail. The higher detection
accuracy and better dynamic performance are ensured by adopting sliding window with
different width as low pass filter according to the balanced or unbalanced load. The
experimental results validate that the active power filter based on the proposed algorithm
can serve different compensation purposes well, and has satisfied accuracy (total harmonic
distortion of current after compensation reaches to 1.31% in steady-state experiments) and
dynamic performance (total harmonic distortion of current after compensation is lower than
4% in dynamic experiments and the DC link voltage is almost not affected) .
Keywords: current detection; active power filter; harmonics; power factor