CONTROLLING METHOD FOR INDUCTION MOTOR BY PWM INVERTER

摘要

PURPOSE:To know a correct magnetic flux component and a torque component by increasing a discriminating divisions equally divided from the circumference of magnetic flux vector direction discriminating means by a microprocessor as large as possible to calculate. CONSTITUTION:Magnetic vector direction discriminating means 8 outputs any of 12 types as magnetic vector position signal phii according to the clockwise rotating angle from the d-axis of a magnetic flux vector phi. Control signal generating means 9 selects the optimum voltage vector according to a magnetic flux increase/decrease signal phix from magnetic flux comparing means 6 aud a torque increase/decrease signal taux from torque comparing means 7, and turns ON, OFF switching elements so that a 3-phase PWM inverter 2 generates it.