Power capability and efficiency comparison of direct drive PMSG at different power control strategies

The authors present the results of experimental work on a small-power direct driven permanent magnet synchronous generator reactive power compensation comparison with two methods. Particular generator is targeted for small size wind power systems, and is tested on a wind turbine emulator that consists of an AC induction motor, a frequency converter and a torque feedback. Generator output power was measured with three different setups: AC-DC converter and a DC-DC boost converter; capacitor compensated AC-DC converter and a DC-DC boost converter; frequency converter with field oriented control of synchronous generators. Simulation and experimental results of generator output power and efficiency are obtained and analyzed at different generator speed values.