| 摘要 |
PURPOSE:To remove voltage having specific frequency through a low capacity device, by connecting a single phase PWM converter to an impedance inserted into a DC system line and supplying compensation current such that voltages at the opposite ends cancell the voltage having specific frequency. CONSTITUTION:A single phase PWM converter 15 is connected through a transformer 16 with a compensation reactor 17 inserted into a DC system line. At first, two-phase sinusoidal voltages ea, eb having specific frequency and phases shifted 90 deg. from each other are produced from a voltage generating circuit 1, then they are fed together with pulsating components va, vb of rectified voltage vd to an operating circuit 3 so as to calculate actual and imaginary voltages p, q. DC components p', q' of the actual and imaginary voltages p, q are taken out and a current command ia' is produced accordingly. Then the current command ia' is compared with an output current ia from the transformer 16, and the difference is employed for carrying out switching control of the converter 15 so as to feed compensation current to the reactor 17. |
