A study of fuzzy control algorithm applying to induction motor soft-starter

Soft starter is the equipment which can control AC motor startup safely. It can not only effectively eliminate the impact on the state grid and the load and torque in the powertrain of the motor, but also improve service life of the AC motor. For these reasons, soft starter is widely used in our working which is related closely with induction motors. Above all, in order to control the AC motor starting up stably and safely, we design a novel method namely multi-slope and current-limiting fuzzy control algorithm. This technique synthesizes the respective superiority that slope voltage control method with the current limiting function and fuzzy control algorithm owned only each other. Then we evaluate the control system based on soft starter through the Matlab/Simulink and experimental tests from the hardware circuit we have been designed. The results show that the control algorithm can control AC Motor with a small current to start and the current tend to be more smoothly than each algorithm only in the whole process. We get perfectly effective controlling of the starting of motor.