A sensorless speed control strategy for a low-cost full-closed-loop servo driver system

In digital system, a full-closed-loop configuration using a tachometers and an analog-digital converter with low resolution results in bad speed control and therefore influences the positioning performance in a high-precision positioning system. However, on the other hand, speed information cannot be accurately obtained through the encoder using traditional estimations. In this paper, we proposed a speed estimator - Kalman Filter by getting the position information through the encoder. The rules of selecting key parameters such as noise covariance in Kalman Filtering were modified to avoid trial-and-error. Experimental results in a control point of view showed a good performance both in normal and low speed range so that a full-closed-loop high-precision servo drive system could be achieved with a low-cost configuration.

[1]  Guangjun Liu,et al.  On velocity estimation using position measurements , 2002, Proceedings of the 2002 American Control Conference (IEEE Cat. No.CH37301).

[2]  Seung-Ki Sul,et al.  A new motor speed estimator using Kalman filter in low-speed range , 1996, IEEE Trans. Ind. Electron..

[3]  Ronald H. Brown,et al.  Analysis of algorithms for velocity estimation from discrete position versus time data , 1992, IEEE Trans. Ind. Electron..

[4]  R.D. Lorenz,et al.  High resolution velocity estimation for all digital, AC servo drives , 1988, Conference Record of the 1988 IEEE Industry Applications Society Annual Meeting.

[5]  Sheng-Ming Yang,et al.  Performance evaluation of a velocity observer for accurate velocity estimation of servo motor drives , 1998, Conference Record of 1998 IEEE Industry Applications Conference. Thirty-Third IAS Annual Meeting (Cat. No.98CH36242).

[6]  Guanrong Chen,et al.  Kalman Filtering with Real-time Applications , 1987 .

[7]  Yusuf Altintas,et al.  High Speed CNC System Design. Part II : Modeling and Identification of Feed Drives , 2001 .

[8]  Kenzo Kamiyama,et al.  A Microprocessor-Controlled High-Accuracy Wide-Range Speed Regulator for Motor Drives , 1982, IEEE Transactions on Industrial Electronics.

[9]  T. Başar,et al.  A New Approach to Linear Filtering and Prediction Problems , 2001 .