| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve the estimation accuracy of a phase current. <P>SOLUTION: This phase current estimating device 10 for a motor includes a phase current estimating section 23 estimating a phase current based on the DC-side current of an inverter 13 detected by a DC-side current sensor 31. The phase current estimating section 23 estimates a current value at each point in the phase current at timing symmetric relative to a carrier peak point in each voltage pattern symmetric relative to the carrier peak point at a maximum value or a minimum value in one cycle of a carrier signal, and includes a carrier peak point current value calculating section 23a calculating, as the current value of the phase current at the carrier peak point, an average value in terms of current values at the timing of two points each of which is one point estimated by the phase current estimating section 23, and a phase current calculating section 23c calculating the current value of the phase current at the carrier peak point and the current value of the phase current at optional timing in one cycle of the carrier signal based on a discretization formula obtained by discretizing the current equation of the motor 11. <P>COPYRIGHT: (C)2010,JPO&INPIT |
