Output Power Smoothing for Wind Turbine Permanent Magnet Synchronous Generators Using Rotor Inertia

Abstract

Due to wind speed variations, the output power of wind turbines fluctuates. This power fluctuation can cause frequency deviations and power outage, particularly when wind power penetration is significant. Energy storage devices, such as batteries, ultracapacitors, super inductors, and flywheels can be utilized in a hybrid system to solve this problem. These methods are effective, but they impose a significant additional cost to the system. This article presents a novel control method to mitigate the power fluctuations using the rotor inertia as an energy storage component. Therefore, the additional energy storage system is not required. The proposed method is also modified to obtain better energy capturing efficiency. The efficiency of the algorithm is evaluated based on developed equations. The energy extracting capability using this method is comparable to other methods such as the maximum power extraction algorithm. Simulation studies for various cases are performed on a permanent magnet synchronous generator, which verify the theoretical analysis.