| 摘要 |
<p>PROBLEM TO BE SOLVED: To decrease the number of parts in a circuit and reduce the circuit scale by comprising a noise filter and a current transformation means wherein, with the noise filter coil as primary side, the primary current is transformed with a secondary coil for detecting a current value. SOLUTION: A coil L1 is inserted into one power source line between an AC power source and a rectification bridge 20, while a coil L2 is inserted into the other power source line between the AC power source and the rectification bridge 20. The coils L1 and L2 are wound oppositely in phase, forming a line coil 10a together with a core, as a whole. Here, relating to the line coil 10a, the coils L1 and L2 are wound for different turns. And the current flowing a primary side line coil 10a is transformed with a secondary side coil L3. Thus, the line coil 10a and the coil L3 constitute a current transformation means 10.</p> |
