| 摘要 |
PURPOSE:To prevent system down by preparing effective and reactive power detection systems in an uninterruptible power source equipment and separating the uninterruptible power source equipment when the difference between the effective and reactive power is higher than a specific level. CONSTITUTION:Output phase voltage and output current are multiplied through multipliers 4a, 14a to produce effective current detection values P1, P2. The output phase voltage is shifted by -90 deg. through phase shifters 5, 15 and multiplied by the output current through multipliers 4b, 14b to produce reactive power detection values Q1, Q2, P1, P2 and Q1, Q2 are compared through comparators 16a, 16b and an abnormal detection output is produced from an OR gate if any one difference exceeds over a predetermined value then the uninterruptible power source equipment is isolated. |
