A digital method for detecting harmonic currents based on instantaneous reactive power theory

作者：He Yingjie^*; Liu Jinjun; Wang Zhao'; an; Zou Yunping

来源：Transactions of China Electrotechnical Society, 2010, 25(8): 185-192.

• Conventional detection
• Digital methods
• Fast convergence rate
• Flexible control
• Harmonic currents
• Harmonic detecting
• Harmonic detection
• Instantaneous reactive power theory
• Least mean squares
• Misadjustment
• Real time algorithms
• Theoretical expression
• Variable step size

The choice of the cut-off frequency reflects a tradeoff between maladjustment and the speed of dynamic response in the conventional detection method based on instantaneous reactive power theory. The paper proposes a novel digital real-time algorithm for detecting harmonic currents. This algorithm adopts a new variable step size least mean square(LMS) adaptive filter as LPF on harmonic detection circuit. The step-size is large when the algorithm is far from the optimum with decreasing as it approaches the optimum. The proposed algorithm allows more flexible control of misadjustment and fast convergence rate without the need to compromise one for the other. Meanwhile approximate theoretical expressions for the behavior of the algorithm are derived. The additional calculation is very little, so the algorithm presented is easy to implement. Simulation and experiment results illustrate that the performance of the proposed approach is satisfactory.

• 出版日期2010
• 单位华中科技大学