Optimum control strategy of grid connected PMSG wind turbine based on energy storage system

Abstract

Nowadays, wind energy, as a source of electrical energy, are growing rapidly to substitute fossil energy. The power generated wind turbine is fluctuating that is influenced by wind speed so that it takes the appropriate controlling to get the maximum energy and the constant power for grid. This paper presents control for variable speed permanent magnet synchronous generator (PMSG) wind turbine that is connected to the grid. To extract the maximum power, Particle Swarm Optimization (PSO) method is used to get optimal power coefficient (Cp) through setting duty cycle for the boost converter. Control of bidirectional converter is aimed to control the DC-link voltage and smoothes the delivered power to the grid using the battery as energy storage. Bidirectional converter controlling will set the charging and discharging of the battery to meet the power grid required using a PID controller. To achieve unity power factor, voltage source inverter is controlled using PI control. Based on simulation results, the controller has worked very well. PSO can maintain Cp at optimal value of 0.48 against wind speed variation. DC-link voltage could be maintained at constant value of 400V for changes in wind speed through setting the charging and discharging of the battery by bidirectional converters.