Shinji Arinaga

Modeling and simulation of variable speed wind generator system using boost converter of permanent magnet synchronous generator

This paper proposes the variable-speed wind generator system using the boost converter. The proposed system has three speed control modes for the wind velocity. The control mode of low wind velocity regulates the armature current of the generator with the boost converter to control the windmill speed. The control mode of middle wind velocity regulates the DC link voltage with vector controlled inverter to control the windmill speed. The control mode of high wind velocity regulates the pitch angle of the wind turbine with the pitch angle control system to control the windmill speed. The hybrid of three speed control scheme extends the variable-speed range. The proposed system simplifies the maintenance, improves the reliability, and reduces the cost in compare with variable- speed wind generation system using PWM converter.

Power variation control of a wind generator by using feed forward control

The pitch control of wind generators is usually made by a feed back control concept. However, under the conditions where a wind speed changes very frequently due to geographic reasons of the site and the target system has large rotor inertia, the feed back signal which is applied to the control system to compensate disturbance such as wind speed variations is delayed, and consequently the control strategy to keep the generated power at a constant value does not work well. If the wind speed shows too much variation, this will cause a violent variation of power and result in step out operation of the generator from the power system due to magnetic saturation. This paper proposes a control strategy to reduce the power variations by introducing feed forward control combining with the conventional feed back control.