集中补偿型LCL-APF的有源阻尼控制方法研究

针对电网中采用无源网络进行滤波后仍然存在的谐波及无功问题,采用LCL-APF系统在变配电所侧对电网中的谐波及无功分量进行集中补偿。该LCL-APF系统采用直接功率控制的策略,省去了复杂的谐波检测及计算环节,改善了网侧电流的失真情况,将电网电流的谐波畸变率从26.86%降到了3.78%。通过机理建模及波特图分析,在功率控制环内加入有源阻尼环节,有效抑制了三相LCL系统引起的谐振问题,提升了LCL-APF系统的动态性能。仿真结果证明了该控制方法的正确性与可行性。

Research on the active power damping control of LCL-APF based on concentrated compensation

For reducing the harmonic and reactive power of the grid after being filtered with reactive network, a LCL-APF system is applied to decrease the remain harmonic and reactive power of the grid for concentrated compensation in the transformer substation. The direct power control method is adopted which omits the detection and calculation of harmonic and reactive current and improves the distortion of grid current which is decreased to 3.78% from 26.86%. Moreover, through the analysis of the mathematical model and bode figure, the active damping method is applied in the power control loop for suppressing the resonance of three-phase LCL, which promotes the dynamic performance of LCL-APF. Simulation results show that the proposed method is correct and feasible.