Modelling, design and implementation of a small-scale, position sensorless, variable speed wind energy conversion system incorporating DTC-SVM of a PMSG drive with RLC filter

[摘要] Wind energy has proven to be a viable source of clean energy, and the worldwidedemand is growing rapidly. Variable speed topologies, with synchronous generatorsand full-scale converters, are becoming more popular, and the e ective control of thesesystems is a current trend in wind energy research.The purpose of this study is the modelling, design, simulation and implementationof a small-scale, variable speed wind energy conversion system, incorporating the positionsensorless direct torque control with space vector modulation, of a permanentmagnet synchronous generator, including an RLC converterlter. Another aim is thedevelopment of a gain scheduling algorithm that facilitates the high level control of thesystem.Mathematical models of the combinedlter-generator model, in the stationary androtating reference frames, are presented and discussed, from which equivalent approximatetransfer functions are derived for the design of the controller gains.The design of the controller gains, RLClter components, gain scheduling conceptand maximum power point tracking controller are presented. It is discovered that theRLClter damping resistance has a signi cant e ect on the resonance frequency of thesystem.The system is simulated dynamically in both Simulink and the VHDL-AMS programminglanguage. Additionally, the maximum power point tracking controller issimulated in the VHDL-AMS simulation, including a wind turbine simulator. Thesimulation results demonstrate good dynamic performance, as well as the variablespeed operation of the system.The practical results of torque and speed controllers show satisfactory performance,and correlate well with simulated results. The detailed gain scheduling algorithm ispresented and discussed. Anal test of the complete system yields satisfactory practicalresults, and con rms that the objectives of this thesis have been reached.

[发布机构] Stellenbosch University