| 摘要 |
The invention concerns a device comprising a controllable grounding transformer (1 ) arranged to compensate for a residual operating current in grounding of an alternating- current network having a power transformer (3). A primary winding of the grounding transformer (1 ) is coupled to the power network or a power source synchronized to the power network and a secondary winding of the grounding transformer (1 ) is coupled to between a zero point (N) of the power network and ground (E), wherein the grounding transformer (1 ) comprises two or more tap-changers (10a, 10b) and the device includes a unit configured to control the tap-changers (10a, 10b) for controlling secondary voltages of the grounding transformer (1 ) in respect of amplitude and phase angle (a) in relation to the voltage system of the feeding power transformer. Further the invention concerns a method of producing a zero-point voltage in an alternating-current network by using the device. |
