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So far anne has created 8 blog entries.

Sorensen Lecture on Symmetrical Components

This is the slide deck from a lecture on Symmetrical Components by Dean Sorensen of National Grid. Dean's lecture was presented under the auspices of the IEEE Power Engineering Society in the Boston area in the Fall of 2013. Working knowledge of this approach which derives from a paper by Charles Fortescue back in 1918 is essential in this business. Unfortunately the ideas don’t come easily and take considerable getting-used-to. Dean's presentation is the best short treatment of the topic we've seen. [read full article]

3-phase flips

There are some insidious wiring errors that happen with 3-phase power quality instruments which can make it look the instrument has failed. Here’s a table that will help you recognize one of the nastiest ones. [read full article]

Two Meter 3-phase Metrology

One aspect of 3-phase power metrology that’s not very well-known is that it’s possible to fully quantify the system with just 2 voltage/current measurements. This is commonly referred to as a, “corner grounded delta” configuration or sometimes as the “two meter method.” One day I decided to see if I could derive this from first principles on my white board and got lucky on the first try. This is a picture of my derivation which my colleagues jokingly called, “Yaney’s Conjecture.” [read full article]

Voltage Induced in the Rogowski Coil due to a Threading Current

This is a short derivation of the Rogowski equation written with my colleague Dr. Kartikeya Tripathi back in 2010. The first time a new user observes the remarkable properties of the Rogowski geometry (first published by Rogowski and Steinhaus in 1912) to create a current measuring aperture with a flat spatial response and also to reject stray magnetic fields form non-threading currents it looks magical. Like all things magical, it is not. [read full article]

Fourier for Power Signals

We are huge fans of the Goertzel DTFT for frequency domain analysis of power signals. This is a short paper by my colleague Dr. Kartikeya Tripathi from April 2010 written in the context of an instrument based on the ADE7878 IC from Analog Devices. He goes through the background and explains the issues in the first 3 sections and then presents the Goertzel IIR filter approach in Section 4. [read full article]

Schneider MV Design Guide

This publication from Schneider Electric and is just so useful, compact and well-done that we include the entire text here. This is a valuable reference for all relevant aspects of the medium voltage environment that forms the distribution segment of the electricity grid. [read full article]

PRIME technical overview

This is a brief technical overview of the PRIME OFDM PLC system that is finding increasing application for AMI systems in Europe. [read full article]

Fulcriron paper on Overvoltages and Insulation

This compact paper written by D. Fulchiron of Merlin Gerin in 1995 remains one of the best treatments of overvoltages and insulation requirements for utilities in the DJA library. Merlin Gerin is a major manufacturer of circuit breakers and other distribution equipment and was acquired by Schneider Electric in 1992. It is unfortunate that there does not appear to be a proper reference to this paper anywhere for citation but it’s just so helpful we include the entire text here. [read full article]