Design And Optimization Of 160kW Direct-Drive Permanent Magnet Wind Power Generator

With energy and environment problem increasingly prominent,to develop clean energy becomes a strategic choice of the world.Because of it is clean and efficient,wind energy become one of the most important new energy.Permanent magnet direct-drive wind turbines have eliminated the gearbox,which is of high failure rate,thus the maintenance cost is reduced,and the reliability of wind power system is improved.The background and foreground of wind power is the point that this topic is selected.After expounding the advantages and disadvantages of different permanent magnet synchronous generator(PMSG)classifications,this paper chose the radial-flux surface magnet structure as the basic structure of the generator.According to the basic theory of electric machine design,this paper completed the initial electromagnetic design scheme of 160 kW PMSG.In order to optimize the permanent magnet direct-drive wind turbines starting resistance moment and improve the utilization rate of wind energy,this paper put forward a new method of magnetic pole shift to weaken the cogging torque;The offset angle calculation formula of magnet group shifting is given after thoroughly analyze the cogging torque generation principle;The correctness of the calculation formula is verified with the aid of finite element software;The rule of how to select group number is summarized,and the simulation of different group number verifies the correctness of the rule.Results show that the shifting methods can be concise and effective to weaken the cogging torque of permanent magnet motor.What's more this paper overcomes the shortcomings that traditional finite element has a long cycle when optimizing the motor,adopts the genetic algorithm to optimize the generator,with a multiple objective function for generator efficiency,power factor and economic cost.In the end,this paper use Maxwell 2D to simulate the running characteristic of the optimized generator,and dose experiment to test the prototype.Simulation and experimental results verify the rationality of design scheme in this paper.