| 摘要 |
PURPOSE: To attenuate high-frequency components, generated by voltage modulation on the coil of a motor, without bringing about the phase shift of a logical signal corresponding to the position of a rotor by supplying a current in a phase identical to that of an induced voltage in the coil. CONSTITUTION: An inverter 10 supplies a current to the inductors L1 , L2 , L3 of a brushless DC motor 20. The voltages V1, V2, V3 are induced by a motion rotor and are linearly dependent on the speed of a rotor. The voltages of phases ϕ1 , ϕ2 , ϕ3 are transmitted to a rotor relative position detecting block 30. The rotor position detecting block 30 transmits three logical signals through terminals P1 , P2 and P3 to a central control device 70 for transmitting a command signal to the six transistors T1 to T6 of the inverter 10, according to a function of the above-mentioned information, a current value IM and a reference speed WR. Almost all of the high-frequency components generated from voltage modulation on the inductors L1 , L2 , L3 are attenuated. |
