| 摘要 |
PROBLEM TO BE SOLVED: To automate the switching of a high harmonic wave compensating operation and a reactive power compensating operation by generating a higher harmonic wave compensating power command by the quantity of instantaneous effective power AC and the quantity of instantaneous reactive current AC at the time of lagging phase of the quantity of instantaneous reactive current and a reactive power compensative power command at the time of phase lead of the quantity of instantaneous apparent DC. SOLUTION: A low-pass filter 426 produces the quantity Qd of instantaneous apparent power DC by removing the quantity of AC from instantaneous power Q. A judging circuit 427 judges whether the instantaneous reactive DC component Qd phase is lagging or leading, and gives the signal to a code inverting circuit 423'. The code inverting circuit 423' generates the signals (-Pa, -Qa) made by inversion of the codes of the quantity Pa of instantaneous effective power AC of the quantity Qa of the instantaneous reactive power AC when the quantity of instantaneous power AC is of lagging phase, as an effective power command P* and a reactive power command Q*. Moreover, when the quantity Qd of the instantaneous reactive power AC is phase leading and besides the load is light, this can produces the signal (-Qd) made by inversion of the quantity of DC, as a reactive power command Q*. |
