Low-Voltage Ride-Through Coordinated Control for PMSG Wind Turbines Using De-Loaded Operation

Low-voltage ride-through (LVRT) is important for the grid integration of wind power systems (WPSs). Each grid operator defines a grid code, including the LVRT requirement, considering their power system characteristics. During grid faults, LVRT is needed for the protection of WPS because the over current can induce damage to the power converter system. An important issue in the LVRT method of WPS is the energy capacity because sufficient reserve energy capacities of wind turbine inertia and an energy storage system (ESS) are needed for a successful LVRT operation. Although ESS can store excess energy of the WPS during a grid fault, it is physically limited considering its energy capacity. Moreover, WPS has a low reserve energy capacity, especially when the WPS operates in high wind speed conditions. Thus, we propose the deloaded operation of WPS for the preparation of LVRT by reducing the power generation of WPS. The effectiveness of the proposed method is validated by modeling a WT and an ESS topologically and performing simulations using the MATLAB/Simulink SimPowerSystems toolbox.