Wind power system state estimation with automatic differentiation technique

Abstract

A wind power system state estimation method based on automatic differentiation technique is presented in this paper. A simplified RX model of wind turbine is introduced and used to be equivalent to wind power generator. As one of the state variables, the slip of wind power generator is introduced into state estimation process and the corresponding mathematical model is established. The proposed method takes into account the own characters of asynchronous generator and can easily combine with the original state estimation program. Furthermore, unlike the traditional method which needs to deduce all the formulas of derivatives and code them by hand, the Jacobian matrix is built automatically using automatic differentiation with sparse technique in the proposed method, the truncation error is avoided effectively, and the computational efficiency, speed and precision can be significantly improved. This paper demonstrates that the burdens of software developers are relieved greatly by automatic differentiation technique instead of hand-coded derivatives and the simplified RX model instead of the traditional RX model. Finally, it follows from the simulation results that the proposed method possesses good performance and can be well applied to state estimation for power system containing wind power generators.