Abstract
This thesis develops a position sensorless permanent-magnet synchronous motor (PMSM) driven wind turbine emulator and performs its micro-grid connected operation. First, the basics concerning micro-grids, wind generators, turbines, PMSMs and switch-mode rectifiers (SMRs) are explored. Then a standard surface mounted PMSM (SPMSM) driven wind turbine emulator is established. The SPMSM drive can be operated in conventional turbine speed mode or specific wind turbine torque-speed mode. Various wind turbine torque-speed curves under different wind speeds can be faithfully emulated. Next, an observed extended-EMF (EEMF) based sensorless controlled SPMSM driven wind turbine emulator is developed. Through proper starting and dynamic controls, it possesses good driving characteristics being comparable to those of the standard one. For performing faithful loading test for the wind turbine emulator, an interior permanent-magnet synchronous generator (IPMSG) followed by a three-phase Vienna SMR is established. The maximum power point tracking (MPPT) function for the wind turbine emulator driven IPMSG with Vienna SMR is achieved using perturbation and observation (P&O) method. The commutation tuning to optimize the IPMSG developed power and the fault-tolerant operation of the Vienna SMR are also conducted. Additionally, to let the developed turbine emulator be powered from the utility grid with good power quality, a single-phase bridgeless boost SMR is designed and implemented. Then a complete SMR-fed wind turbine emulator driven IPMSG system is established and evaluated. Satisfactory operating characteristics are verified experimentally. Finally, the micro-grid powering application of the developed turbine emulator is presented. It is used to replace the wind generator in the studied micro-grid to express its effectiveness.