A Coordinated Dual-Channel Wide Area Damping Control Strategy for a Doubly-Fed Induction Generator Used for Suppressing Inter-Area Oscillation

Doubly fed induction generators to enhance inter-area damping based on a Robust controller: $${{\varvec{H}}}_{2}/{{\varvec{H}}}_{\infty }$$ Control

In this study, an auxiliary damping controller based on a robust controller considering the active and reactive power control loops for a doubly-fed induction generator for wind farms is proposed. The presented controller is able to improve the inter-area oscillation damping. In addition, the proposed controller applies only one accessible local signal as the input; however, it can improve the inter-area oscillation damping and, consequently the system stability for the various working conditions and uncertainties. The oscillatory modes of the system are appointed using the linear analysis. Then, the controller’s parameters are determined using the robust control approaches ($${H}_{\infty }/{H}_{2})$$ H ∞ / H 2 ) with the pole placement and linear matrix inequality method. The results of the modal analysis and time-domain simulations confirm that the controller develops the inter-area oscillation damping under the various working conditions and uncertainties.

Research on an Output Power Model of a Doubly-Fed Variable-Speed Pumped Storage Unit with Switching Process

The doubly-fed variable-speed pumped storage (DFVSPS) is an effective method to balance the fluctuation of renewable energy generation and is an important means of frequency and voltage regulation of a power grid. Firstly, this paper introduces the structure and mathematical model of the DFVSPS unit. Secondly, the control methods of each switching stage in generating mode and pump mode are proposed, and the simulation study of each stage of DFVSPS switching process is carried out by MATLAB/Simulink. Thirdly, when studying the regulating effect of DFVSPS unit in the power system, due to the high switching frequency of converter in the electromagnetic transient model, the simulation speed is very slow and the data volume is large, so the model of DFVSPS unit needs to be simplified. By analyzing the dynamic behavior of the pumped storage power station, the mathematical model of output power of the DFVSPS unit is established, which includes start-up stage, load ramping stage, stable operation stage, load rejection stage and shutdown stage of generating mode and pump mode. Finally, the simplified model of DFVSPS unit is applied to a simple power system to verify its regulating effect on grid power.