Device for determining a parameter signal for a voltage-fed load

摘要

A device for determining a load operating parameter signal, such as the flux of a rotary field machine, has an integrating circuit added at the input of the instrument transformer with a transfer function k/(1+sxk/ omega N) that amplifies reduced low frequency load voltage inputs to the transformer to avoid calculation inaccuracies due to the transformer transfer error. Circuitry having the inverse transfer function located at the output of the transformer compensates for the amplification distortion.