Development and Hardware Implementation of a Phasor Measurement Unit using Microcontroller

Abstract

As the world continues to move towards a Smarter Grid day by day, it has become the necessity to incorporate real-time monitoring of the grid wherein the instantaneous snapshot of the health of the grid can be made available. No other parameters than the Instantaneous Phasors, considered to be the heart-beats of the Electrical Grid, can represent the complete health status of the grid. This paper discusses how an Open Hardware Platform (Arduino Due with ARM Cortex M3 Micro-controller) can be used to estimate the phasors of a three phase system in real-time. The Pulse Per Second(PPS) signal from a GPS module is used to generate the sampling pulses. These pulses synchronise the sampling process by the Analog to Digital Converters(ADC), used by the PMU throughout the globe because of the high accuracy of the atomic clocks in the GPS satellites. The microcontroller uses a 64-Point DFT algorithm to estimate the phasors. The reference time is obtained from the GPS module which is the UTC time, with which the phasors are time stamped and displayed in a real-time Graphical User Interface(GUI) designed using Python(another open source programming language)