Power quality analysis is a deeper dive

To start off, it’s important to know that proper PQ does not involve just studying voltage and current of the facility. It’s what’s behind the scenes, your harmonic content, your harmonic order of said content, your Power Factor (PF), various pulse drives and how they interact with each other, your sine wave captures and distortion, ground references/paths and how these different types of systems all affect each other. Power quality and its analysis is a deeper dive than just what a typical voltmeter will show. APQ uses “Class A” power quality analyzers that typically capture 512 sampling per cycle or greater. This allows our trained power quality engineers to view sine wave captures with enough resolution to determine what the specific event is and how to mitigate it.

A capacitor bank is a piece of equipment all utilities have on their electric distribution system. It is there to reduce volt-amps reactive (VAR) /losses and improve primary power factor. This piece of equipment operates several times a day and causes sinusoidal distortion.  Most of us know that voltage is provided or ‘’pushed’’, and current is drawn. The utility may cause the sinusoidal distortion on only voltage but due to voltage and current working hand in hand (one will always affect the other), this distortion causes a direct fault on current or the customer side. These events are very short in duration, typically a half cycle and are referred to as ringwaves. Sensitive equipment can often have issues with this type of distortion due to zero crossing errors from the ring wave event. The magnitude of the ring wave event is dependent on the size of the capacitor bank and how close your facility is to the event.

We typically recommend any facility running Variable-Frequency Drive (VFD), Programmable Logic Controller (PLC) or logic to be 1000 ft from any primary capacitor bank where the electric utility is operating on a daily basis. Even outside of this 1000ft you can still have issues. This is where the Power Quality Analysis comes in. We perform our investigation using our power quality analyzers, we collect sine wave data and determine that it is indeed a capacitor bank ring wave event, and we outline how to properly mitigate or ride through these types of events. It is imperative we stress the fact that only a Power Quality Analyzer, not a Power Quality logger can capture these events. Obviously, the issue isn’t ring wave events every time. There are 10s of thousands of different types of sine wave captures and each capture can interlay and affect other types of distortion.

In addition to sine wave distortion, harmonic distortion also needs to be analyzed. We analyze what its content is and whether or not it is within limits (IEEE 519). It is important to know that it is not only the content level but also what makes up the content, the specific harmonic order. Each harmonic order has its own unique effect on the facility’s electrical equipment. Once we identify if harmonic content is of concern, we go into recommending harmonic mitigation units. Whether that is an actual harmonic correction unit (HCU), filtering or surge protection device (SPD) with built-in filtering.

Power Quality Analysis – vital aspects

These are many vital aspects that go into a true power quality analysis.  Aspects such as ride through from utility breaker or recloser operations, correcting power factor, providing a proper surge protection/grounding strategy as well as other aspects to prove proper power quality.

To put all the above into perspective, Utilities must operate their equipment on a regular basis, and in most cases several times a day in order to maintain proper voltage levels and current capabilities to its customers. With the rapid change of technology in customer facilities comes many challenges for the customer and the utility. Customers are seeing much of the robotics, VFD’s or logic-controlled equipment, led lighting, printed circuit boards, etc. being susceptible to transient voltages.

Transient voltages are generated by many different types of issues or events such as lightning or other weather related issues, normal maintenance issues on the utility or customer side such as corrosion of connections or improper maintenance, and the list can go on and on. Due to the changes in today’s modern equipment, Power quality has made its way to the forefront of not only what customers want, its what they need for their equipment to operate properly and to last it’s intended lifespan.

Let APQ help your business realize its full potential. Let APQ conduct a Power Quality study to find any hidden issues that are costing you money, whether it would be downtime, lost product, equipment failures, high electric bills. Let APQ give your business a ‘’clean bill of health’’.