The modern variable-speed drive (VFD) is a sophisticated power electronic system, yet the front end is still a deceptively simple six-pulse diode bridge. That simplicity means the rectifier has little…
Voltage
High Impedance Faults: Causes, Risks, Detection Techniques
High impedance faults can be a troublesome power quality issue affecting not only utilities, but their customers too. Frequently, these faults can trip arc fault breakers and GFCI outlets and…
Why You Should Transition ProVision to PQ Canvass
Introduction If you own a Power Monitor’s recorder you’re probably quite familiar with ProVision. If you aren’t, it’s Power Monitors’ Windows desktop application that lets you manage your PMI recorders,…
Phasor Decomposition via Symmetrical Components in Three Phase Systems
Introduction When three phase systems are perfectly balanced sinusoidal waveforms, where the B and C phases are exact replicas of the A phase sine wave, but delayed by 120 and…
Interharmonics and RMS Variation
Interharmonics occur when a signal is present in a power system where the frequency is not an integer multiple of the 60 Hz line frequency. These can be generated from…
Voltage Imbalance and Its Impact on Waveform Distortion
Voltage imbalance, also referred to as voltage unbalance, is an important power quality issue that can lead to significant operational problems in customer equipment. It occurs when the magnitudes or…
Voltage Regulation in PQ Canvass
PQ Canvass is a web-based power quality analysis software developed by Power Monitors Inc. It combines the foundational elements of Canvass with the features of ProVision, providing a set of…
Riding Through Voltage Sags with the IEEE 1668 Standard
Voltage sags are the most common power quality issue, and also the most costly for industrial power users. It's not practical for a utility to eliminate all sags, so industrial…
Analyzing Portable Power Station Inverter Power Quality
An engineer at PMI purchased a portable power station and wanted to verify the quality of the inverter before attaching sensitive electronics. The steps used to quantify the output quality…
Interharmonic Analysis with Python
Traditional harmonic analysis in electrical systems has revolved around looking at the spectral content on, well, the magnitudes of harmonic frequency components. The IEEE 519 specification provides guidelines for measuring…
Canvass Multiburst
MultiBurst is a feature of Canvass which provides a secondary user interface for easily requesting and receiving real-time data from multiple devices at the same time. This allows for quick,…
Introduction to Voltage Transients
Transients due to nearby lightning or switching events can cause degradation or failure of almost any electrical equipment. Impulsive transients can pass through transformer interwinding capacitance to appear on the…
