Voltage Controller for a Synchronous Generator with Exciter

Abstract

In this paper, the excitation controller for a synchronous generator (SG) with an exciter is presented, based on novel stabilization feedback actions comprising the SG rotor current and rotor voltage measurements. The novel stabilizing feedback actions are used to compensate the dynamic lag introduced by the exciter machine, and to improve the overall excitation system's dynamic performance without employing differential control actions. Namely, by avoiding differential control actions, an improved level of performance can be achieved without compromising the control system's sensitivity in relation to the measurement noise. Also, compared with the existing solutions based on a different set of stabilizing feedback signals, the controlling structure proposed in this paper enables a more stable and faster dynamic response, which is illustrated in the paper by means of the system frequency response analysis. The performance of the proposed solution is verified through the set of simulation and experimental runs presented in the paper. While the controller design is based on a simplified generator model, the simulations are carried out using the full order generator and exciter models. The experimental tests were carried out on a 300 MW thermal power plant aggregate with an AC exciter.