Secondary Frequency Control for a Microgrid with Wind /Storages Based on Improved Virtual Synchronous Generator

Abstract

Due to small capacity, limited size and low inertia of isolated island operation microgrid, the frequency of microgrid is greatly affected by the change of load. Islanding operation for multi sources micro grid, traditional virtual synchronous generator control can overcome the shortcomings of low inertia of micro grid, but it belongs to the droop control, it will be possible to make the micro grid's frequency cannot recover after a large disturbance and cause system frequency deviation, and affecting the frequency stability of the whole system. The improvement of virtual synchronous generator control is proposed with the integral controller in damping based on the traditional virtual synchronous generator control, it can automatically track the load fluctuation and adjust the power output to achieve power balance and zero-error frequency. Micro grid simulation model made in Matlab/Simulink platform wind /storages s, in the islanding mode, the traditional and improved virtual synchro-nous generator control is adopted to study the frequency change of load load switching and verify the correctness of the proposed control strategy.