| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a system linkage inverter that is reduced in changes caused by a temperature and an age, and can stably compensate a direct current by precisely detecting a DC component. <P>SOLUTION: The system linkage inverter has a DC determinator 4 that inserts a resistance element R1 into an inverter output in series, and outputs a signal to extract the DC component included in the output current to compare it with a reference value. When the extracted DC component is out of a previously set reference range, a control unit 2 outputs the signal that changes bias setting for converting a direct current to an alternate current. The DC determinator 4 comprises inverted amplification circuits 14a, 14b formed at two stages, and a pair of comparison circuits 16a, 16b connected in parallel with each other. The determinator is constituted such that an amount of the alternate current is reduced by the inverted amplification circuit 14a at the front stage and an amount of the direct current is amplified by the inverted amplification circuit 14b at the rear stage. When the direct current detected at each comparison circuit 16a, 16b is out of a prescribed range with a zero point as a center, the signal is output. <P>COPYRIGHT: (C)2007,JPO&INPIT |
