ANORDNING ANSLUTEN TILL ETT VEXELSTROMSNET FOR ATT AVKENNA SPENNING I DETTA OCH ATT GE ETT UTGANGSVERDE SOM ER PROPROTIONELLT MED FORHALLANDET MELLAN NETETS LINJESPENNING OCH FREKVENS

摘要

A measuring device for an over- excitation protection device comprises an integrator 1 and a peak value measuring means 15, 18, 19, 20 and 21. The monitored voltage, applied across the terminals 10, 11, is integrated during a half-cycle, whereafter the voltage of an integration capacitor 13 is measured by the peak value measuring means and then discharged. The times for the peak value measurement and the capacitor discharge are determined with the aid of a zero detector 15 connected to the voltage source.