Proof of concept data logger for non-active power measurement

This paper discusses a metering concept design based on equipment cheaper and smaller than a laptop and able to meet the requirements of power measurements that need relatively high frequency, simultaneous sampling. Its size and cost make it useful when developing hardware for smart grid systems. Non-active power is a term used to describe both distortion and reactive power. In conventional power theory, the apparent power, S, and non-active power, Q, are based on RMS measurements of voltages and line currents. A novel general power theory was proposed recently to give a measure of the true efficiency of power delivery under conditions of distortion, unbalance and direct current components, and the approach requires the simultaneous sampling of all voltages and currents at relatively high frequency. A metering device was designed for the measurement of instantaneous, simultaneously sampled voltages and currents in a three-phase system. The system has an upper sampling frequency limit of 2 000 Hz. The prototype design was fast enough to perform the general power theory calculations and log the data accurately. The project provides direction for the further development of this type of device for measuring non-active power, power quality and power electronic control.