Research On Small Size Switched Reluctance Wind Power Generator System

Firstly,the research background,structure characteristics,control methods and working modes of small-size switched reluctance wind power generator are introduced in this paper,and the research status of sensorless control and efficiency optimization control on switched reluctance generator system are summarized.Secondly,a new method of position estimation based on non-conduction phase current injection is proposed.The reasons of angle error in estimation are analyzed,and an error compensation strategy based on linear changing region of inductance is proposed-,especially at high speed.The effect of estimation error on output power is analyzed in simulation.Compared with the existing methods,the proposed method has many advantages,such as high accuracy of position estimation,wide range of speedand small amount of needed calculations.Thirdly,according to the above proposed position estimation method,an efficiency optimization method of generator system based on phase current RMS value is presented.The impacts of switch angle on phase current RMS value are analyzed,and the optimal angle regions under different working points are obtained.Then in this region,the optimal angle is searched online to make the SRG work at the minimum point of the phase current RMS value.The influence of current injection section on the efficiency at the optimal angle is analyzed in simulation.Fourthly,according to the application requirements,the main power circuit and control circuit of switched reluctance generator system are designed,and the appropriate switch device and digital controller are selected.The diagram of system efficiency optimization strategy and the software flow chart are given under the current injection sensorless control.Finally,the proposed control strategy is validated by experimental platform.The experimental results show that the proposed position estimation strategy has the advantages of high precision,low power loss and the wide speed rangefor switched reluctance generator sensorless control.Taking the phase current RMS value as the control target can improve the efficiency and reduce the switching loss.Online search can quickly and accurately determine the optimal switching angle to ensure the SRG works at the minimum point of copper loss.