Control Strategy based on Parametric Lyapunov Theory for Wide-area Damping Controller Considering Remote Signal Transmission Time Delay

Abstract

Remote signal transmission time delays are the major factors affecting damping performance of wide-area damping controller (WADC), and it even deteriorates small signal stability of large-scale power system. Traditional time delay damping controller based on linear matrix inequalities (LMI) has relatively large conservatism and complexity. Conventional time delay compensation controller suffers large amount of simulations and there is no general formulation to determine control parameters. In this paper, the design method of wide-area time-delay damping controller based on parametric Lyapunov theory is derived. The explicit expression of the controller parameter value associated with the time delay is determined. The controller is determined according to the system stability original definition (The system energy function is finite and positive and its first derivative is negative), which avoids complex matrix inequalities cyclic solution and reduces the conservatism of the controller. Moreover, it can directly give simple and explicit control law and specific control parameters, which enable this method to adjust its parameters online according to the exact time delay obtained by GPS. Case study is undertaken based on the New England ten-machine 39-bus power system. Compared with the free weight matrix controller, which is a kind of LMI-based design strategy with excellent performance, the effectiveness and superiority of the proposed design method for WADC are verified.