Abstract:Recently APF (active power filter) has been widely used for the reduction of the harmonics and improvement of the power quality in power systems. However, a PWM-based APF generates harmonics at the switching frequency and its multiples, and may produce EMC (electromagnetic compatibility) problems. Randomization of the switching frequency causes the harmonic components with high magnitude on switching frequency extend as low magnitude harmonic components with a bandwidth. The magnitude of harmonic components can be reduced. In the paper, the randomized PWM technique is used to overcome the harmonics problems of the APF caused by the high frequency harmonics. Detailed analyses and the PSD characteristics of the RPWM for suppressing switching frequency harmonics of the APF are presented. A practical design procedure of the randomized PWM technique is proposed. Simulation and experimental results confirm the validity of such technique.
李辉, 吴正国. 采用随机脉宽调制技术降低电力有源滤波器开关谐波[J]. 电工技术学报, 2010, 25(8): 105-109.
Li Hui, Wu Zhengguo. Reduction of Switching Frequency Harmonics of Active Power Filter Using Randomize PWM Technique. Transactions of China Electrotechnical Society, 2010, 25(8): 105-109.
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