NOVEL AND ACCURATE INSTANTANEOUS POWER MEASUREMENTS

This paper presents a novel approach for real time measurement of all electrical quantities in a power system signal based on a new least squares algorithm. The advantage of this approach is that the least squares algorithm is an easy to understand, fast and cheap method that can be applied to track changes in power rapidly. The technique can be used to accurately evaluate the rms voltage and rms current magnitudes and phase angle of each harmonic component directly from single measurements of voltage and currents. Once the magnitudes of voltage and currents have been evaluated all other quantities such as average power and power factor can be readily calculated. To confirm the theoretical analysis, computer simulation has been used and tested with a hypothetical signal. For comparison, similar simulations have been repeated using the FFT with the same number of samples and sampling period.

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