Control system design for a 20 kW wind turbine generator with a boost converter and battery bank load

Abstract

This paper describes the design of a boost type DC/DC converter for a 20 kW wind turbine generator. The generator phase inductance is big enough so no extra DC inductor is required. The electrical system is modeled using the power electronics and motor control software package PSIM, then a current controller is designed. Its steady state and transient performance shows that the generator phase inductance helps to smooth the generator phase current with a reasonable lagging angle. Furthermore, a simple current-torque model is derived for the electrical system. This model together with that of the mechanical system enables the design of the speed control loop based on the turbine tip speed ratio (TSR), the ratio of the blade tip speed to the wind speed. The simulation result based on MATLAB/SIMULINK shows the power tracking with wind variation. The whole control system is being implemented using an embedded controller.