Sliding Mode Observer Design for Permanent Magnetic Synchronous Generator Based Wind Energy Conversion Systems

Abstract

Real-time rotor position and speed information is essential for effective power control of permanent magnet synchronous generator-based wind energy conversion systems. The presence of traditional encoders can increase the size, cost and complexity, but also reduce the overall system life-time and reliability. To provide a more reliable sensorless wind generation control scheme and eliminate the reliance on encoders, this paper presents a novel high order sliding mode observer for power control of permanent magnet synchronous generator-based wind energy conversion systems. Compared with the first order sliding mode observer, a high order sliding mode observer shows superior estimation accuracy with significantly reduced chattering effect. A three-level neutral-point-clamped space vector pulse width modulation (NPC-SVPWM) based power converter is used to reduce the voltage stress on power switching devices and produce less harmonics in the output waveforms compared with a traditional two-level inverter. Computer simulation results have shown the superior performance of the purposed high order sliding mode observer in wind turbine power control applications.