Ride-through of adjustable speed drives during voltage dips

Adjustable speed drives are reported to be very susceptible to voltage dips. This paper investigates the behaviour of standard induction motor drives in the power range from 2.2 up to 7.5 kW for different types of voltage dips. Voltage tolerance curves are presented and an optimal selection of the under-voltage protection is proposed in order to maintain operation without loss of performance. The opportunities, provided by an active front end and a boost converter, to improve the ride-through of standard drives are investigated and their effect on the voltage tolerance curves is considered. (C) 2003 Elsevier Science B.V. All rights reserved.