| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve an accuracy of detecting a current supplied to a load even if a switching element and a temperature sensor of a resistance for current detection are housed in the same space. <P>SOLUTION: An inverter has a switching element section 23 for supplying a driving current to a motor 3, a shunt resistor 26 provided between the section 23 and the motor 3, a temperature sensor 30 for a heat sink which are provided on a heat sink 21 and are housed in a package. In driving the motor 3, the temperature elevation of the resistor 26 is calculated on the basis of a loss of the resistance 26 according to the driving amount required to the motor 3 and a thermal resistance of the sensor 30 and the resistor 26, and the elevation is added to the temperature of the heat sink to estimate the shunt resistance temperature. Then, a resistance value of the resistor 26 is corrected on the basis of the estimated shunt resistance temperature to calculate the driving current to be supplied to the motor 3. In this way, the section 23 is driven so that the driving current is supplied to the motor 3. <P>COPYRIGHT: (C)2003,JPO |
