Estimation of stator resistance and rotor speed for IPMSG using model reference adaptive system

Abstract

In order to achieve optimal control of an interior permanent magnet synchronous generator (IPMSG) used in wind power plants, parameters of the generator need to be identified or estimated. Furthermore, since mechanically mounted speed sensors can cause plant failures, sensorless control is preferred and generator rotor speed needs to be estimated. Model reference based methods are one of the most used methods for combined stator resistance and rotor speed estimation in permanent magnet synchronous motors. In this paper an estimation of stator resistance and rotor speed using model reference adaptive system (MRAS) is presented. The MRAS consists of the reference and adjustable model where the reference model is used to determine the required states (d and q current components) and the adaptive model provides the estimated values of the states. Simulations were conducted for different rotor speed values and expected stator resistance variation due to temperature increase under load. Simulation results show that the MRAS model gives satisfactory estimates of rotor speed and stator resistance.