As I outlined in my posts “Power Quality: Measuring to Manage” and “How Today’s Meters Make Power Quality Data Easier to Understand,” measurement and analysis are the critical first steps in any power-quality improvement program. Putting what you’ve learned to use, though, means knowing the best solutions for the problems you’ve identified. Here, I’ll cover corrective-equipment options, and then offer some suggestions for how to implement a continuous-improvement process to take a facility’s power-quality performance to the next level.
Equipment to solve Power Quality problems
Manufacturers have developed a range of equipment to help consulting engineers and facility personnel address specific power-quality issues. In some cases, the options are pretty cut and dried, while situations may require a bit more thought.
- Transients. Transient voltage surge suppressors are the best option for protecting against transients in a power system.
- Voltage sags and interruptions. The best choice here depends on extent of any interruption. Uninterruptible power supplies and other energy-storage options could do well with shorter-term sags or interruptions, but back-up generators or self-generation equipment is needed when longer outages are encountered. Other solutions could include static transfer switches and dynamic voltage restorers with energy storage. Schneider Electric’s MGE Galaxy 5000 series.
- Harmonics. Active filters are the recommended solution for harmonic mitigation, thanks to their flexibility and high correction performance. Alternative approaches could involve passive filters, multi-pulse arrangement transformers or harmonic correction at the equipment level (for example, by integrating harmonic filtering into variable speed drives). The AccuSine power-correction system from Schneider Electric offers a complete harmonic-filtering solution.
- Power factor. Reducing power factor requires producing reactive energy as close as possible to connected loads. Installing capacitors on the network, such as Schneider Electric’s VarSet LV capacitor banks, is the easiest and most common way to achieve this goal.
With all these approaches, remote monitoring capabilities have become a standard customer request. Today’s end users want to be able to verify the efficiency of any applied corrective actions – possibly through a dashboard-style interface, as shown in Figure 1.
Taking power quality to the next level
Addressing power-quality issues is often a reactive process – a response to a problem that has already occurred. But by implementing a more proactive process of continuous power-quality improvement, facility managers can minimize the risk of costly future problems and interruptions and maximize both operational efficiency and equipment lifespans. The following short- and long-term steps can help facility managers improve their uptime, energy efficiency and asset management:
- Within the next few weeks: Plan a project roadmap. As a starting point consider monitoring the power quality at plant level, or at critical areas with sensitive loads.
- Within the next 6 months: Analyze the results of your monitoring and their impact on your equipment and installation. Assess the power-quality correction technologies. Identify an initial project with reasonable investment that can result in positive results over a relatively short period of time (for example, an immediate opportunity to deploy power-quality equipment for a particular device or process).
- Within the next 12 months: Plan methods for expanding power quality more broadly throughout your organization. Collaborate with internal stakeholders and/or seek out expert services organizations that have the technical expertise and global presence to support a long-term infrastructure integration project.
You can find more information on the measurement, analysis, corrective equipment options and the benefits of monitoring for continuous improvement in a new Schneider Electric white paper, “A Framework for Implementing Continuous, Iterative Power Quality Management.”