Special aspects of flicker compensation in MV power supply systems with rapidly fluctuating active loads

High-power combustion engine test benches are supplied by converter-fed AC asynchronous drives (ASD) which have to provide the counter-torque necessary for testing, e.g. for simulating engine acceleration and braking processes, with an ASD power consumption in the megawatt range. These test processes are characterized by rapidly fluctuating active power with a relatively low and constant reactive power consumption since modern control techniques as well as IGBT AC side converter are used. The active power fluctuations may cause inadmissible power quality impacts in form of voltage fluctuations and flicker effects which have to be observed and, if necessary, compensated. These aspects are analyzed in the paper with special focus to their consequences in the power supply system.