These days everyone agrees that power quality is just as important as power availability. In fact, focusing more on power quality issues will improve system stability and performance more than focusing solely on outages. Why? Knowing how much power is available won’t point out lurking problems in the background such as transients, voltage unbalance, voltage sags, voltage regulation concerns, or harmonic distortion levels. The focus needs to change to ensure reliable power systems.
Most power quality monitoring is reactive. Monitoring equipment is usually purchased after a warranted incident with the hopes of catching it next time.
Moving to a proactive permanent system can spot situations and environments that are responsible for the problems. These permanent systems can spot an event or favorable condition capable of triggering a problem. Fluctuations like voltage regulation and unbalance, transients, or harmonics can all be precursors of a coming event.
The power quality monitoring framework also needs to operate in real-time to be effective. Irregularities in steady-state power qualities can be shown in statistical distributions and identified in time trends.
And the advantage of adjustable speed drives is all but negated when supply system capacitor-switching transients or voltage sags make them trip.
When it comes to battery backup options, generator problems can develop due to motor restarts. The chillers need to start up as soon as possible. If monitors are installed at the backup generator and main supply, the entire system performance can be evaluated.
Harmonic distortion level characterization should be another process being monitored. This would help gauge the requirements for power conditioning, transformers, and wiring.
Where a monitoring location is situated depends on the power conditioning equipment, the design of the facility being monitored, critical loads, and the precise goal is of the monitoring. Battery backups, generators, power conditioning equipment production, and utility supply locations are the beginning of the base to watch. If a facility has more than one backup solution, then each feed needs to be monitored. Monitoring inside of the facility will help to spot patterns with problems in load interactions.
One utility supply that installed on-site monitoring was able to catch over fifty disruptions in the initial three months. They installed monitoring on the input as well as the output of the UPS system. All power quality information from the monitoring was able to be accessed over a web browser. The system then sent an email to all suitable personnel when it spotted an issue or needed to raise a warning.
The disruptions were found to have been due to transients and sags that might have gone on to affect vulnerable loads. When they investigated further, they realized a bad relay on the utility end was the cause.
Reliable system monitoring shows the weaknesses and needs for improvement before an outage occurs. Better monitoring can improve resource adequacy. A system’s adequacy can be improved by keeping the transmission and distribution lines flowing and reducing plant outages. System monitoring is a needed and integral part of restoring confidence and stability even with increasing demand. Higher-level functions of data analysis and warnings make system monitoring more important than ever. Teams able to coordinate and collaborate from various locations through web browsers speed up the process and find solutions before problems occur.
With a little planning, thorough review, and multi-level team consultations, improved power quality can mean more reliable power systems.