| 摘要 |
PURPOSE: To prevent the lowering of driving torque at the time of high temperature in an electric car using an induction motor as a driving source. CONSTITUTION: This control device for an electric car is provided with a d.c. power supply, an electric motor for driving the electric car, a torque command computing means for determining a torque command for the electric motor in accordance with an operation command and a slip frequency computing means 50 for computing a slip frequency on the basis of the torque command and a rotation angular velocity of the electric motor. The slip frequency computing means 50 is provided with a slip frequency limiting means 532, 535 for setting the maximum value of the slip frequency and a slip frequency limiting- value correction means 533, 534 for correcting the maximum value of the slip frequency in accordance with the operating conditions of the electric car. Also, it is provided with a slip frequency limiting-value correction means 522 for correcting the limiting value of the slip frequency in accordance with the temperature of the electric motor. Therefore, the lowering of the torque of the electric motor can be prevented at the time of high temperature. |
