Investigation Converter Circuit «Voltage-Current» for Power Calibrator

The paper presents alternative circuits for voltage-current converters to be used in the calibrator of fictitious power. The experimental studies have revealed a number of problems related to the stability of the system in deep feedback and zero level stabilization of the amplifier. The circuit solutions given in the article allow elimination of these problems and improve the accuracy of calibrator current calibration. For example, correction/corrective circuits are used to ensure the stability of the converter at deep depths of the feedback, and operational amplifier based circuit solution and compensation condition are proposed to reduce the additional phase shift. To improve the accuracy of the calibration current values specified by the calibrator we propose to connect the feedback circuit to the measuring current transformer. However, further improvement of the accuracy class of the power calibrator is impossible without modern electronic components. (paper)