The Digital Soft Braking for Wind Turbine

The mathematical models of hydraulic braking system were built through studying the braking system of the wind turbine. The AMESim software was used to establish the simulation model of hydraulic braking system and the controller model, which was employed to the coupling of the simulation, constructed in Matlab/Simulink. The designed soft braking system was tested in the wind turbine. The analysis results of the simulation and the test show that the rotor speed decreases gently and the fluctuation of the gearbox torque is diminished at the soft braking based on adjusting the duty cycle of PWM which controls the ON/OFF of the high-speed switch valve.