Induction motor controller

摘要

The invention is an induction motor controller for measuring electrical constants of a polyphase induction motor (102) by supplying test power thereto with a polyphase inverter (101) and driving/controlling said polyphase induction motor (102) with said polyphase inverter (101) using a result of this measurement for parameters of driving control; said controller comprising a current control means (401) for controlling said polyphase inverter (101), and applying a specified DC command voltage to said polyphase induction motor (102) being at rest to supply a DC current thereto; and a resistance estimating means (501) for inputting thereto said DC voltage and said DC current, computing total resistance (R1a+R2a) of primary resistance (R1a) and secondary resistance (R2a) in a first period immediately after the supply of a current by said current control means (401), computing the primary resistance (R1b) in a second period following said first period, subtracting said primary resistance (R1b) computed in said second period from said total resistance (R1a+R2a) having been computed in said first period and estimating said secondary resistance (R2b).