| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotor position detecting device for a brushless DC motor that reduces the number of parts and material costs at a circuit part required for position detection for miniaturization. SOLUTION: This rotor position detecting device is equipped with an operation part 230, first and second comparison parts 240 and 250, and a rotor position detection circuit part 260. The operation part 230 mixes the output signal of a first integration part 210 that integrateds a signal inputted via the virtual neutral point of a three-phase power supply line connected to a bruchless DC motor 14, a signal that calculates the the output signal of a second integration part 220 for integrating a signal inputted from one phase of the three phase power supply line and a proportional coefficient R, and a signal that performs the operation of a proportional coefficient L to the one-phase current for outputting as the one-phase current. The first comparison part 240 compares the one-phase signal outputted from the operation part 230 with a preset first reference value. The second comparison part 250 compares the one-phase signal with preset second and third reference values. The position signal calculation part 260 calculates the output signal of the first and second comparison parts 240 and 250 for calculating a position signal. |
