Discussion of "Active voltage correction for industrial plants"

The author comments on the paper by D. Ezer et al. (see ibid., vol.38, p.1641-6, 2002), briefly reviewing the proposals put forward. The author discusses the proposal to use active voltage conditioners (AVCs) as a solution to mitigate the effect of voltage sags in industrial plants, pointing out that this seems to be effective for the case studies mentioned but not, in his opinion, for a general case. The author also points out an apsect not considered in the paper which is the synchronization of the additive voltage injected by the series transformer with the voltage supply in the distribution system in order to mitigate phase jumps.