| 摘要 |
PURPOSE:To eliminate lag in the rising of brake power and to prevent abrupt increase of brake power at the time of starting dynamic brake in an electric vehicle wherein an induction motor is subjected to drive control through an inverter unit and applied with dynamic brake. CONSTITUTION:A dynamic brake control means 12 for variably controlling the slip frequency of an induction motor at the time of starting dynamic brake to produce predetermined brake power is provided while including a slip frequency setting section 12g for providing the dynamic brake control means 12 with a preset constant negative polarity slip frequency, a slip-frequency switching section 12h, and a switching control section 12i for determining the operational timing at the slip frequency switching section 12h. |
