| 摘要 |
PURPOSE:To operate an electric automobile over wide range of variable speeds by limiting the electric current of an AC motor for driving the automobile to a torque current component in a low speed region and controlling he phase of the output power of an inverter with respect to the induction voltage of the motor in a middle to high speed region. CONSTITUTION:The torque T of an AC motor for driving electric automobile is fixed until the rotating speed of the motor reaches N1 and the output P of the motor is fixed within a range of rotating speed from N1 to N3. In addition, the output P of the motor is reduced at a rotating speed equal to or higher than N3 Within a range of rotating speed from N2 to N3, the motor is constantly operated at the maximum output so that the d-axis reactance component Xd2 at the rotating speed N2 can meet the formula by controlling the q-axis current component of the motor in accordance with a required torque, the d-axis current component of the motor based on the maximum voltage value, induction voltage, d- and q-axis reactance components, and q-axis current component of the motor, and the voltage of the motor constantly at themaximum value. The Im and Em of the formula respectively represent the maximum current value and maximum voltage value of the motor and n2=N3/N2 and n1=N2/N1. |
