| 摘要 |
<p>PURPOSE:To prevent performance of an electric car from deteriorating on the occasion of switching of power source voltage, by switching an arc-extinguishing circuit which turns off a thyrister chopper in accordance with power source voltage. CONSTITUTION:In case when an electric motor 7 is driven by an electric car line 1, a switch 16 is closed on contact A side, and first arc-extinguishing circuit which consists of a commutation capacitor 13 and a commutation reactor 14 is selected. When the power source is changed over from the electric car line 1 to a battery 4 by operating a changeover switch 3, the changeover switch 16 is closed on contact B side, and second arc-extinguishing circuit consisting of a commutation capacitor 13a and a commutation reactor 14a is selected. It is possible, by doing so, to prevent deterioration of performance of an electric car even at the time when the power supply voltage is switched.</p> |
