| 摘要 |
A device for continuous supervision of the attenuation (d), dissymmetry (k) and mismatch (v) system parameters in impedence earthed power systems. The parameters are calculated from the circle diagram uEN=f(v), i.e. the relative neutral point voltage as a function of the mismatch. The circle diagram is in turn defined by two measuring points for uEN which are derived by connection or disconnection of a reactance complement between system neutral and earth. The invention improves known devices for control of condition in impedence-earthed power systems. Then the continuous a supervision of the mentioned power parameters enables, inter alia, a better detecting of high-resistive earth connection. The invention can be implemented in any computer system capable of providing the necessary measurement, control and calculating functions. |
