Motor acceleration study are performed on industrial and large commercial systems where large motors can have unwanted consequences on the performance of it and surrounding equipment. The starting current of most AC motors is several times (5 to 7) the normal full rated load current when starting from full line voltage. These large current requirements can result in Nuisance tripping of protection breakers, Excessive running currents, drop-in terminal voltage, triggering of under-voltage relays, Low starting torques resulting in a failure to start, stalling of other running motors connected to the power system. The impacts will be even more severe as the industry is shifting towards energy-efficient motors where the starting current high as 10 to 12 times the full load current.

The ultimate objective of the motor acceleration studies is to check whether a motor can successfully start or not considering different operating conditions like starting the motor with baseload, starting the motor in the absence of grid (only generator ON condition), and ensuring the system operates within the prescribed voltage limit during the starting transients. Both the static and dynamic motor can be carried out however more detailed information like motor and load dynamic load models are required to perform the dynamic acceleration study. Ideally, a motor-starting study should be conducted before a large motor is purchased, such that the motor can be installed with confidence that the motor’s life and applications performance will be satisfactory, static acceleration is preferred at this stage due to the non-availability of detailed information.