摘要
近年来,电力有源滤波器广泛用于抑制电网谐波、提高电力系统电能质量。对于电网而言,基于脉宽调制技术的有源滤波器等效为高频谐波源,产生开关频率及其倍频成分谐波,引发电磁兼容性问题。随机脉宽调制技术将开关频率随机化,使得开关频率处幅值较大的离散谐波扩展为一定带宽内幅值较小的连续谐波,从而降低开关谐波幅值。论文选取随机脉宽调制技术用于抑制有源滤波器开关谐波,并在此基础上简化电力有源滤波器输出滤波环节,减少设备成本,降低控制系统设计难度。详细分析随机信号对开关函数功率谱密度特性的影响,并据此提出随机脉宽调制技术的实用化设计方法。仿真和实验结果验证了论文方案的有效性。
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.
出处
《电工技术学报》
EI
CSCD
北大核心
2010年第8期105-109,115,共6页
Transactions of China Electrotechnical Society
基金
国家自然科学基金委员会创新研究群体科学基金资助项目(50721063)
关键词
有源滤波器
电磁兼容
电磁干扰
随机脉宽调制
双傅里叶变换
Active filter
electromagnetic compatibility
electromagnetic interference
randomized PWM
double Fourier transformation