LQG/LTR Control of an AC Induction Servo Drive

Ying-Yu Tzou and Hsiang-Jui Wu

IEEE Trans. on Power Electronics, vol. 10, no. 2, pp. 214-221, March 1995.

Index Terms: control system analysis, control system synthesis, digital control, frequency-domain.


A new design method based on the linear-quadratic-Gaussian with loop-transfer-recovery (LQG/LTR) theory has been developed for the design of high performance AC induction servomotor drives using microcomputer-based digital control. The principle of field orientation is employed to achieve the current decoupling control of an induction motor. An equivalent model representing the dynamics of the decoupled induction motor has been developed. Based on the developed model with specified parameter uncertainties and given performance specifications, a frequency domain loop-gain-shaping method based on the LQG/LTR theory is proposed for the design of the servo loop controller. A microcomputer-based induction servomotor drive has been constructed to verify the proposed control scheme. Simulation and experimental results are given to illustrate the effectiveness of the proposed design method.

Power Electronics Systems & Chips Lab., Advanced Power Electronics Center

National Chiao Tung University, Hsinchu, TAIWAN.