| 摘要 |
PURPOSE:To achieve that an insulating amplifier used to measure an input voltage at an inverter is used in common with an insulating amplifier for current detection use and that the mounting area of components on a board and the space of pattern wirings are reduced in an inverter control apparatus. CONSTITUTION:A voltage-dividing resistance 15 voltage-divides the potential difference between one end of a current detection resistance inserted in series with an output from an inverter an an input power supply for the inverter. A selector 19 selects either voltage drop of the resistances 15, 16 and inputs it to an insulating amplifier 21. A timing generation circuit 23 operates a sample-and-hold circuit 24 connected to an output at the insulating amplifier 21 on the basis of ON-OFF signals from power elements 2 to 7 for the inverter. |
