Extended Non-Singular Terminal Sliding Mode Observer for Sensorless Control of Surface Mount Permanent Magnet Synchronous Motor
A GANAPATHY RAM KR Santha
electrical machines and drives
A number of estimation techniques have been developed to achieve sensorless control of permanent magnet synchronous motors (PMSM). Most of them suffer from variation of motor parameters such as the stator resistance, stator inductance and torque constant. Also, it is known that conventional linear estimators are not adaptive to variations of the operating point in a nonlinear system. The sliding mode technique has shown promising results when estimating or controlling nonlinear systems. This paper presents a sliding mode observer (SMO) for estimating the position and speed of a permanent magnet synchronous motor (PMSM) to achieve sensorless drive system. Extended non-singular terminal sliding surface is a superset of conventional non-singular terminal sliding surface, which guarantee the convergence of system state to zero in finite time. It also overcomes the restriction on the range of the exponent of a power function, of non-singular sliding surfaces, whose exponent is a rational number with positive odd numerator and denominator, with the exponent of power function being a positive real number. The stability of the proposed observer is verified using Lyapunov second method and the validity of the observer is demonstrated by simulation and verified by experimental results.
This article is written in Adobe PDF format ( .pdf file ).To view this article you need to download the file. Please rightclick on the link below and then select "Save
target as" to download the file to your harddrive.