Design And Analysis Of High-Speed Permanent Magnet Brushless DC Motor

With high speed, small size power density, efficiency significant advantages High-speed PM BLDC motor have very bright application prospects. However, there are many technical difficulties, such as permanent loss of high-speed motor and vibration noise in the process of designing High-speed permanent magnet motor. The high-speed motor vibration and noise performance of the motor will have a great impact if the cogging torque of motor is not properly solved.In this paper, three main tasks were done to 1.1kW,27000r/min High-speed PM motor the following:Firstly, according to the structure, operation principle and characteristics of the High-speed PM BLDC motor, some designs of the basic principles of electromagnetism were summarized for High-speed PM BLDC motor. According to the basic principles of design and integration the Ansoft program to do the calculation and optimization for the prototype.Secondly, according to the reduction for efficiency of high-speed permanent magnet brushless DC motor by core loss of stator in the design process, the accurate calculation for stator core loss is very important.2-D finite element method is used to analyze the alternating magnetic field and magnetic field of the stator core of which a rotational speed of 27000r/min high-speed BLDC motor. Harmonic analysis is used for the step magnetic field of high-speed BLDC motor, Based on the model of Bertotti iron loss calculation, superposition of various frequency loss will be calculated, the calculation accuracy was validate to increase.Finally, cogging torque ripple is also studied in this paper for High-speed PM BLDC motor. PM motor cogging torque is inherent. It is the case in the motor was caused by the interaction of the motor's own magnetic field and cogging motor when the motor unload. Coupled with the motor structure is not completely symmetrical, the motor will vibrate. Cogging torque of the motor cogging torque can fluctuate, so that the motor can not run stable. Cogging torque also make the motor vibration and noise, if the resonance occurs when the permanent magnet motor, motor vibration and noise will also be extended. In this paper, the vibration and noise problems of High-speed PM BLDC motor cogging torque fluctuations during operation was solved by optimize slot and interspersed winding. At least in the case of MFL, finite element method was used to analysis cogging torque.