| 摘要 |
PURPOSE:To dispense with the rotating position detecting element and to miniaturize the unit and make it as lightweight as possible by detecting the rotating position of the rotor by the low frequency components of the counter- electromotive voltage generated at each stator coil. CONSTITUTION:Stator coils U, V and W are connected to transistors Tr1-Tr6 at output stage and also connected to corresponding low-pass filters 19-21 respectively. These low-pass filters 19-21 extract nothing but the low frequency components of the counter-electromotive voltage generated at their corresponding stator coils U, V and W. The rotating position detecting signals outputted from each low-pass filter 19-21 are processed by a differential amplification circuits 181-183, waveform shaping circuits 184-186 and a logic sequence circuit 187. From the logic sequence circuit 187 the switching signal to on-off control the transistors Tr1-Tr6 is outputted. |
