Prediction of local instabilities in open‐loop induction motor drives
ISSN: 0332-1649
Article publication date: 11 May 2010
Abstract
Purpose
The purpose of this paper is to propose an analytical method for prediction of self‐sustained oscillations that might happen during low‐cost induction motor drive application. This forecast is needed to avoid unwanted oscillations that can be encountered for in fan, compressor and pump drives utilizing open‐loop frequency‐controlled three‐phase induction motor drives.
Design/methodology/approach
The paper presents the model of the induction motor drive system that includes inverter switches dead‐time and allows discontinuous current of front‐end rectifier. Stability analysis of proposed model was performed by tracing the eigenvalues of the overall system matrix.
Findings
Discontinuous rectifier current at light loads and the dead‐time of the inverter switches are the main sources of undesired low‐frequency self‐sustained speed oscillations in open‐loop controlled induction motor drives. The evaluated risk prediction is a function of drive and motor parameters and load level.
Originality/value
The proposed induction motor drive system model highlights the direct connection between the self‐sustained speed oscillations and the system parameters like inverter dead time, dc capacitor values, motor parameters and motor load level. Good accuracy of instability prediction is verified by dynamic simulation and by extensive experimentation.
Keywords
Citation
Vasić, V.V., Marčetić, D.P., Vukosavić, S.N. and Oros, Đ.V. (2010), "Prediction of local instabilities in open‐loop induction motor drives", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 29 No. 3, pp. 865-884. https://doi.org/10.1108/03321641011028369
Publisher
:Emerald Group Publishing Limited
Copyright © 2010, Emerald Group Publishing Limited