Voltage unbalance can cause severe heating in motors and large DC power converters. Although most voltage unbalance is caused by unequal loading among phases, shifts in voltage phase angle can…
Voltage
Voltage Swell from Recloser Operation
A recloser is most associated with brief voltage interruptions, possibly followed by an extended outage if a fault cannot be cleared. Upstream customers experience voltage sag during the reclose attempts,…
Motor Start-Up from All Angles
ProVision has a multitude of graphs available that are great for analyzing the various aspects of motor startup and the PQ issues that arise while operating these devices. Using an…
Voltage Regulation Analysis With Daily Profiles
If there were no variations in distribution load, system voltage regulation would be a simple task. But Ohm’s law dictates that a change in load produces a change in delivered…
Voltage Unbalance with Canvass
Voltages are rarely perfectly balanced in three-phase systems. Although small unbalances are not usually a problem, if this unbalance becomes too great then the unbalance can cause problems especially for…
Analyzing Voltage Sags with ProVision
This white paper provides an overview of how to find and analyze various aspects of voltage sags using ProVision and data captured using PMI's recorders. For a given dataset, where…
Per-Unit Graphing with Canvass
Canvass is a web-based power quality portal designed and developed by PMI to allow users to perform power quality analysis from anywhere they have an internet connection and a web…
Case Study: Impact of Solar Photovoltaic Installations
2012 was a historic year for the U.S. solar industry. There were 3,313 megawatts (MW) of photovoltaic (PV) capacity installed throughout the year, which represents 76% growth over 2011’s record…
Techniques for Analyzing Motor Startups
This paper covers the setup fundamentals and techniques required to obtain the high-quality waveform capture needed to analyze a motor startup. It also reviews the basic electrical characteristics of a…
Three-Phase Motor Start Causes Voltage Dips
In many cases when a local utility customer complains of voltage problems, it can often be traced back to a neighboring electrical load change that has caused voltage dips on…
Measuring Voltage Unbalance
Voltage unbalance can cause severe heating in motors and large DC power converters and an increase in harmonic currents. Fortunately unbalance is easy to measure with PMI recorders and ProVision…
Conservation Voltage Reduction During Peak Loading Times
The Johnson City Power Board is an electric power distributor located in Johnson City, Tennessee, serving over 75,000 customers in 5 counties. JCPB operates and maintains over 2000 miles of…
