Development Of Power Frequency Digital Phase Shifter

In the measurement of high voltage loss, a voltage signal and a current signal which were nearly orthogonal to each other need to be measured accurately. If the phase of the voltage signal was shifted by 90 degrees accurately, thus the phase angle between the voltage and the current would be nearly 0 degrees. The two signals would be then easily to measure accurately together. A digital phase shifter was developed. The phase and the magnitude error of the digital phase shifter is less than 6 mu rad and 110 x 10(-6) up to 150 Hz and 120 V, respectively.