| 摘要 |
PURPOSE:To measure a motor temperature by providing a means which detects a change of the temperature of a steering motor based on a current changing rate just after pulse driving obtained by a current detection circuit. CONSTITUTION:In accordance with inputs of a torque sensor 1 and a vehicle speed sensor 2, by driving the first and second or the third and fourth switching clements through a drive circuit 5 from a control part 4, a power steering motor 10 is driven by a PWM control. When a motor temperature is increased, a time constant L/R is decreased with a riseup speed increased. When the motor temperature is decreased, the time constant is increased with the riseup speed slowed. When a proper motor temperature is stored corresponding to a change of the temperature, the motor temperature can be calculated by a voltage difference. Thus, the motor temperature can be measured. |
