| 摘要 |
PURPOSE:To prevent capacitor voltage from boosting and to sustain electric brake force upon contact loss during regenerative operation. CONSTITUTION:Voltage rise of capacitors 61, 62 is detected through a voltage detector 201 upon contact loss and choppers 91, 92 are turned ON simultaneously by means of a comparator 202. Regenerative energy of inverters 71, 72 is consumed by resistors 81, 82 through the choppers 91, 92. Consequently, the capacitor voltage does not boost and electric brake force can be obtained without stopping the inverters 71, 72. |
