Induction motor drive system

Asynchronous motor is characterized by simple structure,strong and durable,low cost,reliable operation,low torque ripple,low noise,do not need to position sensor,high speed limit.Induction motor vector control speed regulation technology is mature,the asynchronous motor drive system has obvious advantages,so the earlier was applied in electric vehicle drive system,the current is three phase induction motor still the mainstream of the electric vehicle drive system products,but have been other new type of brushless permanent magnet traction motor driving system is gradually replaced.Biggest disadvantage is that driver circuit is complex,high cost;Relatively permanent magnet motor,induction motor efficiency and power density is low.

2.The brushless permanent magnet synchronous motor drive system Brushless permanent magnet synchronous motor can use cylindrical radial magnetic field structure or disc axial magnetic field structure,due to the power density and high efficiency and magnet prices wide speed range,development prospect is very broad,is a strong competitor in the traction motor of electric vehicle,had been used in a variety of electric vehicles at home and abroad.Built-in permanent magnet synchronous motor,also known as hybrid permanent magnet reluctance motor.The motor on the www.dongfeng-motor.com basis of the permanent magnet torque superposition of the magnetic resistance torque,the existence of the magnetic resistance torque to improve motor overload capacity and power density,and easy to weak magnetic speed regulating,expanding the scope of the constant power operation.Built-in permanent magnet synchronous motor drive system design theory is increasingly perfect and further,with flexible structure,design degrees of freedom,is expected to get high performance,suitable for electric cars,high efficiency,high density and wide speed traction drive.

These cause the attention of the peers in the major car companies,especially the Japanese car company colleague's favor.At present,the American car companies peers in new model design mainly USES the built-in permanent magnet synchronous motor.generator stator Surface;also called permanent magnet

torque motor type permanent magnet synchronous motor,against the built-in permanent magnet

synchronous motor,its weak magnetic speed range is small,low power density.The structure of the motor dynamic response is fast,and is expected to get low torque ripple,suitable for used in automobile electronic servo drive,such as automotive electronic power steering servo motor.Sensorless permanent magnet synchronous motor drive system is currently a hot topic in the research of permanent magnet synchronous motor drive system,will become the development trend of the permanent magnet synchronous motor drive system is one of the potential competitive advantage.Permanent magnet synchronous motor drive system often adopts vector control at low speed,high speed with weak magnetic control.