Hisakazu Ninomiya

High-Performance Induction Motor Drive System Using a PWM Inverter

A high-performance speed control system for cage induction motors is described which utilizes a PWM inverter. The effects of primary current coincidence and machine constant variation on system characteristics such as response time, torque precision, and operating noise were investigated. Based on the results obtained, new control methods have been devised; one varies the gain of the current controller in proportion to the primary frequency, and a second compensates for the slip frequency by using the deviation between the flux reference value and the actual value. Effectiveness of the compensation methods was confirmed in tests.

High-Response Digital Speed-Control System for Induction Motors

High-speed response is obtained for a vector control system by using new methods of speed control compensation, even when the secondary flux is lowered as a noise reduction measure. Moreover, simple circuits are developed which generate primary current reference signals quickly.