  This paper discusses the subject of power quality for power converters. The
first part gives an overview of most of the common disturbances and power
quality issues in electrical networks for particle accelerators, and explains
their consequences for accelerator operation. The propagation of asymmetrical
network disturbances into a network is analysed. Quantitative parameters for
network disturbances in a typical network are presented, and immunity levels
for users' electrical equipment are proposed. The second part of this paper
discusses the technologies and strategies used in particle accelerator networks
for power quality improvement. Particular focus is given to networks supplying
loads with cycling active and reactive power.
