| 摘要 |
<P>PROBLEM TO BE SOLVED: To securely protect an electric motor and an inverter from temperature rise caused by down speed change of a transmission in a hybrid vehicle in which the engine and the electric motor are constantly connected. <P>SOLUTION: Rotation frequency of the electric motor at the time of down speed change is calculated, and a current command value is determined based on this and a torque command value at the time of down speed change. Allowance time up to a protective temperature is calculated based on the current command value and the current motor temperature. When this allowance time is less than a prescribed time, down speed change is prohibited, and when it is longer than the prescribed time, down speed change is permitted. When the motor temperature is likely to reach the protective temperature down speed change is prohibited, where rotation of the electric motor is not increased, thereby deterioration of durability of the electric motor and the inverter is prevented. <P>COPYRIGHT: (C)2004,JPO |
