A New Composite Power Control Strategy for Wind Power Stabilization and Fault Ride-through of Wind Storage System

To remedy the shortage of wind turbine in wind power leveling and fault ride-through, in allusion to direct drive wind power generation system based on hybrid energy storage a compound power control strategy, which considered both wind power leveling and fault ride-through simultaneously, was proposed. On the one hand, an improved second-order filtered power allocation method with power error feedback loop was proposed to realtime revise the power response command of super capacitor and battery storage to increase the target power allocation accuracy meanwhile the tracking control effect could be improved, thus the wind power leveling was realized at the same time the service life of energy storage medium was prolonged. On the other hand, a compound power control strategy, in which the grid side convertor acted together with hybrid energy storage, was put forward to realtime revise the power response command of each control quantity and quickly remove the redundant power of the DC bus, so that the fault ride-through capability of wind turbines was improved to make the wind power system basically not affected by grid faults.