Wide Area Measuring System Signals Based Nonlinear Robust Adaptive DC Power Modulation Controller in AC/DC Interconnected Power System

Abstract

The robust adaptive control law is proposed for a HVDC power modulation controller of the interconnected AC/DC power system. Based on the design idea of driving the center of inertia (COI) of different areas to a stable equilibrium point, the proposed controller is applied to damp inter-area oscillation of interconnected AC/ DC system using global signals of a wide area measuring system (WAMS). Designed by the back-stepping method, the robust adaptive control law is adaptive to the unknown parameters and is robust to model error, disturbances and different equilibrium points. Computer results show that the controller proposed is obviously superior to the conventional DC power modulation controller in damping inter-area oscillation and enhancing the power transfer limit. In addition, its performance can well adapt to the change of the equilibrium point.

設計了應用于交直流互聯電力系統的直流功率調制的非線性魯棒自適應控制器。該控制器基于驅動各互聯區域電網的慣量中心至統一平衡點的設計思想,采用廣域測量系統的全局信號,用以阻尼交直流互聯系統的區域間功率振蕩。采用反步法設計的自適應魯棒控制規律使控制器對未知參數具有自適應性,對模型誤差、擾動和平衡點變化具有較強的魯棒性。仿真結果表明,與傳統的線性直流功率調制控制器相比,該控制器對聯絡線的功率振蕩具有優良的阻尼性能,可顯著提高輸電極限,而且能很好地適應運行點的變化。