基于SVG的电网功率因数控制系统

SVG-based network power factor control system

针对非线性冲击负载引起的无功冲击大、功率因数低和谐波污染等电能质量问题,提出了一种基于静止无功发生器(SVG)的电网功率因数控制系统方案。该系统由SVG与无源滤波器构成。无源滤波器实现滤波的同时,还利用其固定的容性无功将感性范围的无功波动拉到从感性到容性范围的无功波动,以减小SVG容量。系统通过瞬时无功功率闭环,实现了功率因数的恒定控制和无功功率的无静差调节。为了使SVG实现解耦控制,在SVG非线性模型的基础上,利用逆系统构造出伪线性系统。考虑建模误差和参数漂移,采用内模控制对伪线性系统进行综合。仿真结果证明该控制系统的正确性。

Aiming at large reactive power impact,low power factor and harmonic pollution caused by nonlinear impacting loads,a SVG-based network power factor control system is proposed,which consists of SVG and passive filter. Besides filtering,the passive filter also changes the inductive reactive power fluctuation into the inductive-to-capacitive reactive power fluctuation by using its fixed capacitive reactive power,which decreases SVG capacity. The closed loop control of instantaneous reactive power is used to realize the constant power factor and suppresses the reactive power impact. In order to realize decoupling control,the pseudo linear system is constructed based on its nonlinear mathematical model with its inverse system. With the consideration of modeling error and parameters drift,the inner model control method is applied to synthesize the pseudo linear system. Simulative results confirm the feasibility of the control system.