| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the deterioration of control performance by correcting an error of an offset voltage of a current sensor caused by a temperature drift or the like. <P>SOLUTION: This inverter control unit comprises: an inverter 2 constituted of a plurality of switching elements; current detection means 4a, 4b that detect current values flowing to a load motor 3; a zero-cross detection means 12a that detects the zero-cross point of the current flowing to the load motor 3; a drive stop means 13 that turns off the switching elements of the inverter 2 for a certain time so that the current value becomes zero; an offset voltage detection means 14 that stores and updates current values outputted by the current detection means 4a, 4b during a period that the current value becomes zero; and an actual current operation means that operates the current value flowing to the load motor 3 from voltage values outputted by the current detection means 4a, 4b and from voltage values stored at the voltage detection means 14. The switching elements of the inverter 2 are stopped for a certain time in accordance with the rotational speed of the load motor 3 at the zero-cross point of the current detected by the zero-cross detection means 12a. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
