| 摘要 |
<p>A method in connection with a protective relay and a protective relay, it being connected to an electrical power network, the method comprising the steps of disconnecting a line, line section or busbar, measuring voltages from the disconnected line, line section or busbar in three phases, forming parameters describing the state of the disconnected line, line section or busbar from the measured voltages, determining a resonant overvoltage of the fine, line section or busbar on the basis of the parameters, and informing the personnel of the electrical power network of the resonant overvoltage or its magnitude and/or frequency.</p> |
