Sensorless Control of Doubly-Fed Reluctance Machines for Wind Energy Conversion Systems

An improved rotor position and speed sensorless controller design for a prominent doubly-fed reluctance machine has been presented and practically validated in generating operating mode being of immediate interest to the target wind power applications. This inherently medium-speed brushless generator type is a good candidate to overcome the reliability and maintenance concerns with conventional wound rotor doubly-fed induction generators which use a vulnerable 3-stage gearbox in such systems. The proposed control method has been successfully implemented on a laboratory wind turbine generator emulator, and its excellent performance verified by the comprehensive experimental results produced in the paper.