| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power supply device that reduces switching loss when a voltage is changed according to the revolutions of a motor. <P>SOLUTION: In this power supply device of this invention that supplies DC electric power to an inverter which drives the motor, a rectifier element is arranged between the positive electrode side terminal of a first DC voltage source and the inverter. Between the connection point of the DC voltage source to the rectifier element and the negative electrode side terminal of the DC voltage source, a series connection of a first switching element to the second one is arranged. Between the connection point of the first switching element to the second one and the negative side terminal of the rectifier element, a second DC voltage source is arranged. The first switching element and the second one are turned on and off according to the rotational speed of the motor to connect the first DC voltage source to the second one in series or in parallel. <P>COPYRIGHT: (C)2007,JPO&INPIT |
