Improved sensorless direct torque control method using adaptive flux observer. Issue 7 (1st July 2014)

• Record Type: Journal Article
• Authors: Saberi, Hossein; Sabahi, Mehran; Sharifian, Mohammad Bagher Bannae; Feyzi, Mohammadreza
• Is Part Of: IET power electronics. Volume 7:Issue 7(2014)
• Page Start: 1675
• Page End: 1684
• Publication Date: 2014-07-01
• Subjects: sensorless machine control -- torque control -- observers -- AC motor drives -- rotors -- stators -- fuzzy control -- robust control -- parameter estimation -- nonlinear systems -- invertors; improved sensorless direct torque control method -- adaptive flux observer -- ac drives -- sensorless applications -- precise rotor speed estimation -- flux estimation -- torque estimation -- stator current -- flux vector components -- state model -- steady‐state conditions -- DTC method -- space vector modulation strategy -- fuzzy logic control -- FLC; Power electronics -- Periodicals; 621.31705
• DOI: 10.1049/iet-pel.2013.0390
• Languages: English
• ISSNs: 1755-4535

Abstract

Abstract : A simple structure and a quick and robust response of the direct torque control (DTC) makes it attractive in ac drives. However, in sensorless applications, a precise estimation of the rotor speed is a crucial issue as along with the torque and flux estimation. In this paper an adaptive flux observer is introduced with a stator current and flux vector components as state variables and rotor speed as an unknown parameter which is estimated by using an adaptive scheme. A non‐linear inverter model is proposed to obtain a more accurate response. Also, torque, flux and current pulsations, during the steady‐state conditions, are considered as the disadvantages of the classical DTC method. A combined DTC and space vector modulation strategy is presented by using fuzzy logic control (FLC). FLCs are designed to obtain a fast response in the transients, and a high accuracy during the steady‐state conditions.