Maintaining Power System Reliability: Three Key Issues
June 4, 2018 - Power & Communication
By Emanuel Kourounis
Quality, reliable power is at the core of any good building safety system: It powers automatic lights, alarms, fire protection systems, electronic locks, and more. In mission critical facilities such as hospitals, data centers and oil and gas refineries, power is what keeps businesses running and occupants safe. With electrical reliability so critical, it would stand to reason that electrical distribution infrastructure is one of the best-maintained equipment systems across facility operations – it is not, however. Despite the incredible risk, maintenance may not be adequately performed due to reduced staffing and business pressures. While preventive maintenance is necessary, the question becomes, “when should it be done?” Answering this question can be difficult, but there are a few basics that must be remembered when it comes to maintaining power system reliability.:
• When determining the appropriate maintenance cycle, consideration should be given to loading, utilization, and environmental conditions. For instance, a circuit breaker in a healthcare facility has different maintenance needs then the same breaker in an industrial application.
• Maintaining electrical reliability is a multi-stepped process. It involves proper design, conducting performance and safety assessments, upgrading aging equipment, and installing connected technology.
This article will focus on these core issues.
Design and Installation
Designing electrical systems with operation in mind is crucial. Careful consideration and thoughtful planning at the start will result in an electrical distribution infrastructure that is tailored to the needs of the facility. Choices made during the design and installation phase will have an increasingly significant impact as facilities become more digitally complex. In the next five to 10 years, there will be more devices connected than ever before. The need for more data will increase. As decisions to replace, modernize, expand, or build new are made, it will be necessary to consider new technologies as part of the strategy to become more proactive to mitigate risk. It will be important to evaluate equipment purchases based on total cost of ownership rather than purchase price. “Value engineering” can reduce equipment to a basic configuration. Options like communications, auto transfer schemes, and relay packages are sometimes removed to reduce cost. Removing technology can hinder the ability to maintain power reliability. It can also complicate the process for adding smart technologies in the future.
How a site is operated also has a tremendous influence on risk and safety levels. The environmental conditions that switchgear (or any electrical equipment) operates in can greatly affect its performance and reliability. Humidity, extreme temperatures, corrosive gases, and dust can reduce the life and performance of electrical distribution equipment. To understand the impact of these factors on equipment, an analysis of normal and fault conditions should be done prior to installation. This includes evaluating the variables of power loss and the level of maintenance needed.
Lastly, any plan for ventilation should avoid the possible negative effects of cold, damp, and dust on the electrical equipment. These factors will impact the layout and organization of switching rooms, choice of equipment, and skill level required from the personnel completing the installation.
An assessment of the electrical equipment is key to successfully reducing risk while improving performance and maintaining power system reliability. There are several key areas to consider when performing a thorough assessment. These include identifying the strengths and weaknesses of the system, the condition of the equipment, the risks to safety and electrical distribution performance, the major risks to the process, and how the information can be used to manage risk and optimize performance. Regular assessments will help a facility manager identify vulnerabilities within the system and provide some guidance for modernization, replacement, or even an expansion of the system.
There comes a time when electrical infrastructure is beyond the point of maintenance, or when facility needs dictate newer solutions. At this point, it is important to consider whether upgrading the existing equipment, rather than replacing it, would be the best course of action. Modernizing electrical infrastructure doesn’t have to mean scrapping the entire existing system. Upgrading or retrofitting a specific area can be the most cost-effective and least disruptive way to improve power reliability.
There are many reasons why infrastructure could be ready for an upgrade or replacement. Issues to consider with older equipment include:
• Safety: Switchgear failure is more likely in older equipment and can cause serious injuries and damage.
• Arc Flash Hazards: Newer technologies have arc flash mitigation techniques that can reduce incident energy levels.
• Switchgear Lifespan: The switchgear lifespan has been extended from 10-30 years to up to 50-60 years. However, industry standards and technology offerings are evolving at a faster rate. This challenges companies to modernize an antiquated system while maintaining power system reliability.
• Spare Parts Availability: The availability of spare parts must be examined. If they are no longer readily available, it is time to upgrade.
• Improved Reliability: Reliability is key for preventing downtime and lowering costs.
• Total Cost of Ownership: Older equipment has a higher total cost due to frequent maintenance needs, the potential and impact of downtime, and increased liability caused by safety hazards.
Modern switchgear solutions significantly improve safety and reliability and consume less floor space. These advantages are enabled by improvements to gas insulation and the introduction of Shielded Solid Insulation (2SIS). These insulations are also less susceptible to external factors such as dust and contamination. In short, these new technologies provide many advantages over traditional air insulated switchgear for similar cost.
In today’s business climate, everyone is asked to do more with less: Resources are being reduced, budgets are tightening, and knowledge bases are retiring. These are serious headwinds in an environment that demands more safety, power systems reliability, and efficiency. Connected technology answers these challenges by enabling personnel to leverage valuable data for better business decisions. Connected technology provides valuable data that allows for the monitoring of a system’s holistic health. Asset performance monitoring systems are relatively inexpensive and can help facility managers understand potential failure and mitigate appropriately. Additionally, a connected system allows facility professionals to remotely monitor the health of their equipment and empowers them to manage and maintain critical electrical systems from any location. This includes having the ability to identify when an asset begins to fail and take immediate action and prevent downtime. These systems can help make power systems maintenance and management less reactive and more proactive and predictive.
This information will be necessary to move towards a condition-based maintenance strategy, where understanding the contributing factors that affect electrical distribution equipment will be needed. Utilization, loading, environmental conditions, and power quality all contribute to electrical equipment failures. Connecting to a monitoring system will not only identify issues in these areas, but will provide historical data to appropriately right-size power system maintenance cycles.
To move towards a connected technology strategy, a proper equipment foundation will be necessary. This includes communication devices (such as sensors and wireless networking) and data modeling platforms that can gather, harness and deliver the right data to be more predictive. Remember, the quality of the data will determine how predictable a system can be.
Reliable power at a facility can be maintained in numerous ways. A stronger design, proper maintenance, and planned upgrades and replacements can significantly improve performance. As market demands shift, more measurement and data-driven insight will become the industry standard. This will require the use of connected technologies that can provide insight that aids CapEx and OpEx planning and makes management more intelligent. Facility managers should begin to prepare for these needs now. The more in tune a facility manager can be with what is happening beneath the surface of the electrical infrastructure, the more smoothly, efficiently, and safely the facility will operate.
Emanuel Kourounis is business development manager, energy business, for Schneider Electric. He has been at Schneider Electric for nearly twenty years with a recent focus on asset performance management.