| 摘要 |
PURPOSE:To reduce a control error by providing a reactor which is inserted between an induction collector coil and a PWM converter and an internally induced voltage detecting circuit which determines an induced voltage in the induction collector coil by computation on the basis of a voltage inputted to the PWM converter and a voltage detected by the reactor. CONSTITUTION:A reactor for detecting an induced voltage, of which the capacity is set to be smaller than an internal inductance L of an induction collector coil 1, is inserted between the induction collector coil 1 and a PWM converter 11. An internally induced voltage detecting circuit 20 takes in a voltage between both ends of the reactor as a detected voltage, while taking in three-phase input voltages V'U, V'V and V'W of the PWM converter 11, and determines three-phase voltages V'SU, V'SV and V'SW corresponding to induced voltages VSU, VSV and VSW in the induction collector coil 1, by computation, on the basis of the above voltage values. According to this constitution, the induced voltages of the induction collector coil can be detected without being subjected to a control error by an effect of a surrounding magnetic field. |
