FIELD POLE POSITION CORRECTING METHOD FOR SYNCHRONOUS MOTOR

摘要

PURPOSE:To set a speed to zero by a simple algorithm as a preprocess by applying a torque command of reverse polarity to cancel a speed change generat ed by the command used in case of obtaining the polarity of the generated torque. CONSTITUTION:A period/speed converter 101 converts a period T to a speed N. A torque command generator 102 outputs a torque command (i). The polarity of the command is reverse between during the discriminating of the polarity and during the preprocessing. After presuming, it becomes a torque command in response to a control. A torque polarity discriminator 103 notified during the presuming or after the presuming of a current phase correcting amount delta0' or during the discriminating or preprocessing of the presuming of the delta0' to the converter 101 and a current phase correcting circuit 104. Thus, reverse polarity torque commands are respectively applied during the discriminating and the preprocessing to cancel the speed change generated during the discrimi nating during the preprocessing.