| 摘要 |
PURPOSE:To reduce the cost of a load controller by applying a large voltage to a load at the time of starting, and applying a low voltage after it is started to be shifted to a normal operation, thereby simplifying a circuit configuration. CONSTITUTION:A load controller requires a high voltage from a DC power source 1 at the time of starting, and starts a load 3 which does not need a high voltage after starting. This is composed of a stepup chopper 2 for starting the load 3 including the power source 1, and a stepdown chopper 4 including the load 3 at the output side. Thus, when the load 3 is not yet started, the chopper 4 is opened to operate only the chopper 3 to apply the stepup high voltage to the load 3, thereby starting it. After starting, the chopper 4 is operated to apply a stepdown low voltage to the load 3. Accordingly, in case of a discharge lamp load 3, a series inductance element L2 for limiting a current can be reduced in size. |
