Enhancing Frequency of Grid-connected Wind Farm using Energy Capacitor System and Trap RC Shunt Damper Strategies

Abstract

In this paper, a combination of the conventional energy capacitor system and a proposed two-trap Resistor Capacitor (RC) shunt damper circuitry is used to stabilize a grid network made up of fixed speed wind turbines, steam turbines and hydro turbines. The energy storage system is connected to the terminals of the wind farm and has the capability of stabilizing the grid network during periods of wind speed change. The two-trap damper has the ability to mitigate the mechanical vibration of the wind turbine and increase its output and rotor speed acceleration during disturbances, so the turbine speed is reduced.  Simulations were run using Power System Computer Aided Design and Electromagnetic Transient Including DC (PSCAD/EMTDC) environment, for scenarios where grid frequency control was not implemented and when frequency control was employed using the energy storage device. A further investigation was carried out in enhancing the performance of the grid network considering the proposed two-trap shunt DC damper control topology. The results show the improved performance of the variables of the wind turbine and the entire grid network during dynamics, due to the coordinated control strategies of the two-trap RC circuit and the energy capacitor system employed. Citation: Okedu, K. E. (2018). Enhancing Frequency of Grid-connected Wind Farm using Energy Capacitor System and Trap RC Shunt Damper Strategies. Trends in Renewable Energy, 4, 96-110. DOI: 10.17737/tre.2018.4.2.0070