Vladislav Davidkovich

Passivity Based Control of Permanent Magnet Synchronous Motor

December 28, 1998
10:00 AM
422 Snell

Abstract

Permanent magnet synchronous machines (PMSM) compose a class of rotating and linear electric machines used in both motoring and generating modes. They have been used for many years in applications where simplicity of structure and a low initial cost were of primary importance. Recent developments in power electronics and digital control through digital signal processors have led to new and significant advances in variable speed PMSM drives for applications ranging from computer peripherals to high efficiency machine tools and robotics.

This thesis concentrates on a control design procedure for a permanent magnet synchronous motor in speed servo applications subject to an unknown, time-varying load torque. The controller provides global stability of the desired operating point, guarantees exponential decay rates for transients, and achieves optimized steady state operation. It also eliminates the need for a large difference between the electrical and the mechanical time constants, and thus concurrently achieves improved performance and reduction of power supply requirements. The design relies on shaping the dynamics of ``incremental energy" by manipulating both dissipation rates and lossless channels in an associated incremental system. Simulations and experimental results verify the control design procedure, and show a good performance with very modest power supply requirements. Practical implementation issues through digital signal processors are analyzed.

The extension of a passivity-based approach to position sensorless control of PMSM is investigated and corroborated via theoretical analysis and numerical simulations.

Thesis Committee:
Prof. Aleksandar M. Stankovic (advisor)
Prof. Gilead Tadmor
Prof. Jack Hanania