Research On Passivity And Sensorless Control Of Direct-driven Permanent Magnet Synchronous Wind Generator System

Wind power as a clean and reliable renewable energy has been rapiddevelopment in recent years, especially the direct drive permanent magnet(D-PMSG) wind power system as one of the most potential wind power systemhas been widely concerned. The main content of the paper is passivity andsensorless control method of the direct drive permanent magnet wind powergenerator side.Firstly, this paper introduces the domestic and foreign overall status of windpower system and its development trend. Then the current converter control methodsfor the wind power system are introduced and analyzed, and the current status andapplication of passivity control in the electrical transmission field are analyzed.Otherwise, it describes and analyzes the research status of sensorless controlmethods for low and high speed operations respectively.Secondly, based on the establishment of D-PMSG wind power system in therotating coordinate system mathematical model and combined the port-controlleddissipative Hamiltonian equations, it establishes the Port-controlled DissipativeHamiltonian (PCHD) model of D-PMSG wind power system at the energy formingperspective of D-PMSG wind power system, and taking the issue of energy andefficiency into account the system adopts stator current optimum control method.Based on PCHD model of the D-PMSG wind power system, this paper comes upwith PCHD and global higher-order non-singular terminal sliding mode (globalNTSM) control to realize the maximum power point tracking (MPPT) control belowthe rated wind speed, and it has much faster response speed and better robustcompared with conventional PI control. Meanwhile, the PCHD and globalhigher-order sliding mode control are applied into the chaos control of wind powersystem, and design the PCHD and global higher-order sliding mode controller basedon the PCHD model of chaotic system to achieve MPPT control in the chaoticsituation.Thirdly, owing to the low detection accuracy and weak anti-interference abilityof the traditional mechanical sensors, the paper studies on the sensorless controlmethods for low and high speed operations respectively. In the low speed situation,it puts forward the pulsing high frequency injection method (HFIM) with acombination of higher-order sliding mode observer methods to make the low speedsensorless controller has better dynamic quality and robustness, and it combines theimproved PCHD controller to get maximum wind energy tracking control ofD-PMSG wind power system with the sensorless under low speed. For high speed situation, this paper proposes a global higher-order nonsingular terminal slidingmode observer to get rid of some kinds of disadvantage of the traditional slidingmode observer, including that it needs to phase compensation, has weak robustness,and verify the correctness and feasibility for design of a global higher-order slidingmode observer. By switching function, the paper combines the low-speed with thehigh-speed method as the full speed sensorless control method for the D-PMSGwind power system.Finally, the paper builds a D-PMSG power system simulation platform for windturbine and system-side control sections, and achieves the MPPT control by PCHDcontroller. And it verifies the designed sensorless control method for the D-PMSGwind power system in low, high and full speed are correct and feasible bysimulation.