并联有源滤波器控制策略研究

有源滤波器(APF)是消除电网中非线性负载产生的电流谐波的有效手段，本文分别对并联APF和并联混合APF的控制策略进行了研究。针对某一类非线性负载，提出了一种在单一同步坐标系下的复合控制器，包含PI和重复控制器。该复合控制器结合了PI和重复控制器的优点，能够消除稳态误差和改善系统鲁棒性。本文详细研究了复合控制器的设计方法，对控制系统稳定性进行了分析。所提控制方法在三相并联有源滤波器系统进行了验证，实验结果证明了所提出的混合控制器具有优异的性能。将有源滤波器(APF)和无源滤波装置(PF)结合起来构成混合有源滤波器(HAPF)是当今的发展趋势，既弥补了无源滤波装置的固有缺陷，又能充分发挥有源滤波器的优势。本文对无变压器型混合并联有源滤波器的设计原则进行了研究，提出了具体的设计方法以及电感值和直流母线电压之间的关系。同时，分别给出了HAPF进行补偿负载电流谐波和阻尼电网电压谐波放大这两种不同应用时的控制策略，对其滤波和阻尼特性进行了详细的分析。为了改善HAPF性能，在控制策略中引入了广义积分控制器。实验结果证明了混合并联滤波装置的优异性能。

Control Stratgies of Shunt Hybrid Active Power Filters

Shunt active Power filters (APF) have been proved to be effective means to compensate harmonic currents caused by nonlinear loads in power systems. The control strategies of APF and shunt hybrid APF are studied in detail .According to a special type of nonlinear loads, a novel compound controller, combining PI controller and modified repetitive controller, is proposed .The proposed compound controller not only can eliminate steady error, but also can improve the robustness of the system. A detailed design criterion for the compound controller is presented based on frequency-response analysis. The designed controller is applied to a three-phase shunt active filter. Several experimental results are also presented to verify the good behavior of the closed-loop control system. The hybrid active power filter(HAPF),which combines active power filter (APF)and passive power filter(PF),is the trend because the HAPF makes up the inherent shortcomings of passive filtering devices and can make good use of the advantages of active power filters. The design rules for transformer-less shunt HAPF are investigated, and the relationships between the values of the output inductance and DC voltage is also derived. Two different control strategies for compensating harmonic current and mitigating harmonic voltage propagation are proposed respectively, and the filtering and damping characteristics of these two control strategies are also detailed In addition, generalized integrator is introduced to the controller to improve the performance of the HAPF. Finally, the experimental results validate that the hybrid active power filter has outstanding performances.