| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve withstand voltage and safety at the output side of a DC-DC conversion circuit. <P>SOLUTION: The electric leakage detection device 20 comprises two voltage-dividing resistors R1, R2 connected in series between input terminals of a DC-AC conversion circuit; a detection resistor Rs connected to a contact point of the voltage dividing resistors R1, R2 at one end; a capacitor C0 inserted in between the other end of the detection resistor Rs and a ground; a first determination part 22 for determining the occurrence of leakage by signal-processing of a detection signal Vs. Insertion of the capacitor C0 in between the detection resistor Rs and the ground isolates the output side of the DC-DC conversion circuit from the ground in DC manner. Therefore since the withstand voltage on the output side of the DC-DC conversion circuit is improved, and high voltage on the secondary side of an isolation transformer will not be applied to the primary side, even if dielectric breakdown occurs in an isolation transformer, and safety is improved also. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
