Landis & Gyr Betriebs Ag

Reinhard Dobele

Ruedi Raschle

Martin King

A circuit is disclosed for measuring reactive energy or reactive power. The circuit comprises a main multiplier, a signal/frequency converter, and a frequency divider all connected in series to form a cascade circuit having an output connected to a display. A 90.degree. phase shifter has an input for receiving a first signal component (e.g., alternating voltage) of the reactive energy or power. A second signal component (e.g., alternating current) is connected to a second input of the main multiplier. The phase shifter has a frequency dependent transfer function K[f]. In order to eliminate the effect of this transfer function on the measurement of reactive power or reactive energy, the arrangement includes a frequency measurement circuit for measuring the frequency of the first signal component and a frequency/signal converter for generating an output signal dependent on K[f]. The output signal of the frequency/signal converter is connected to an input of the cascade circuit so that the frequency dependence of the phase shifter is eliminated from the output of the cascade circuit.

Growing community of inventors

Steinhausen, Switzerland

Reinhard Dobele