Design of SVC for Dynamic Compensation to Improve LVRT of Small Wind Turbine

Abstract: This paper presents a control scheme for voltage and reactive power support of wind turbine generator connected to 11 kV grid. The proposed system consists of variable speed wind turbine coupled to PMSG through gear box, transmission line, transformer, and grid. The generated power is fed to the resistive load (1158W) of admission block of Basaveshwar Engineering College Bagalkote (BEC) and excess generation is fed to the grid. The proposed system employs design of Static VAR Compensator (SVC) comprises shunt capacitor or reactor banks which is switched by the thyristors by means of phase angle modulation to provide a continuous variable VAR injection to the electrical network and helps to improve the capability of Low Voltage Ride Through (LVRT). It is observed from the simulation results during fault condition the voltage dip occurs and when SVC is added to the system the voltage support is increased by 38% and by this the capability of LVRT improves and it maintain the continuity of WTG with grid. The system is also tested by considering hourly and monthly variable wind speed data measured from BEC SCADA for Distribution & Automation Research Centre from the wind mast which is located at Energy Park of BEC Bagalkot. Furthermore the proposed system shows the advantage of voltage and reactive power support at PCC.

Keywords: Permanent magnet synchronous generator (PMSG), Wind energy conversion systems (WECS), Low Voltage Ride Through (LVRT). Static VAR Compensation (SVC).