Optimized reacceleration of the motor load in a large industrial power system

The voltage-controlled time-staggered restart of electrical motor groups following a trip due to voltage sags is termed as "reacceleration schedule". The paper discusses the problems encountered in the design and the validation of the reacceleration schedule of a 200 MW petrochemical complex. Various strategies were investigated to avoid recurring voltage sags and "hanging" voltage situations. The optimization task carried out based on dynamic simulations identified the shortest reacceleration schedule acceptable from technological as well as from equipment overload points of view and validated this under different fault clearing assumptions and system operation cases.