静止无功补偿器(static var compensator,SVC)不仅可以为电力系统提供无功支撑、稳定电压,其附加控制还可以有效提高系统暂态稳定性,但SVC模型参数的不确定性以及广域测量信号时延等外部干扰给附加控制器的设计带来很大的难度.提出了一种基于自适应滑模变结构理论的SVC鲁棒控制器设计方法,所设计控制器能有效提高系统暂态稳定性,并且其对于模型不确定性以及时延有较好的鲁棒性.首先根据区域惯量中心的运动方程建立了包含SVC的电力系统模型;然后将滑模变结构理论应用于电力系统模型中,求得SVC附加控制律,并通过自适应律优化控制器参数;最后通过四机两区域系统以及IEEE9节点系统对SVC控制器效果进行了仿真验证.结果表明,SVC自适应滑模控制器可以有效提升系统暂态稳定性,并且其性能优于传统的线性控制方法.
Using supplementary controller of static var compensator(SVC) is an effective way for enhancing the transient stability of an interconnected power system. In conventional controller design, SVC is usually considered as a first-order inertial model with known parameters. In this paper, a nonlinear controller design method based on adaptive sliding mode control is proposed to design a SVC supplementary controller. The imprecise of the model and the external disturbances such as time-delay are taking into consideration in the SVC model, and the interconnected system with SVC is considered by the center of inertia model. Then the SVC supplementary controller is designed based on the adaptive sliding control theory to improve the transient stability of the power system. Finally, the effectiveness of the proposed controller is verified using two simple systems. Simulation results show that the designed SVC sliding mode controller is robust to the variation of operation conditions and time-delays, and it has a better performance in enhancing the system stability as compared with the conventional SVC controller.