An Improved Observer for the Estimation of Synchronous Generator Damper Current

An improved observer is designed for the estimation of synchronous generator damper current. Compared with existing damper current observer, the improved observer has higher accuracy. Furthermore, initial value selection and absolute stability domain of the observer are discussed in this paper. The improved observer has larger absolute stability domain which gives less pressure to simulation step selection. The condition of well-performed observer even when initial value and startup time of observer are changed is also given. By estimating damper current of synchronous generator in IEEE first bench case for SSR, simulation results testify the validity of improved damper current observer.