An Improved Angular Displacement Estimation Based on Hall-Effect Sensors for Driving an Interior Permanent Magnet Synchronous Motor

• Main Authors: Yi-Yuan Ding, 丁奕元
• Other Authors: 陽毅平
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/42459322346726513033

碩士 === 國立臺灣大學 === 機械工程學研究所 === 99 === This research proposes an improved method of angular displacement estimation based on Hall-effect sensors for driving a permanent magnet motor, no matter which kind of waveform is for its back electromotive force (EMF). The control current with a phase lead angle from the back EMF is then determined to drive the motor. Traditionally, the change of Hall-effect signals were measured both by the capture interrupt and timer-period interrupt functions before the angular displacement was estimated by precise operations in a digital signal processor. Unfortunately, the capture interrupt action was highly sensitive to external noises. The improved method retains the timer-period interrupt function and simplifies the estimation operation so that the controller becomes more robust in terms of the rejection of external disturbances. A 50 kW interior permanent magnet synchronous motor for an electric vehicle is used to verify the proposed angular displacement estimation method for driving the motor, whose back EMF waveform is close to a trapezoidal function. Therefore, the six-step square wave is applied and the proposed angular displacement estimation is used for driving the motor with adjustable phase lead angles. The experimental results show that the improved angular displacement estimation based on the Hall-effect sensors saves so much system resources that the operational speed of estimation is 2.9 times higher than the traditional one. The proposed estimation method has also higher anti-noise ability.