Almost every aspect of modern life is dependent on electricity. From our living room lights and kitchen refrigerators to the streetlights and servers that make the internet possible, it’s all made possible by power stations. To ensure transmission and distribution happen reliably, electrical power stations need the best tools for preventing blackouts, fires, and an array of other life-disrupting problems.
In this post, TherCam, a leading thermal imaging camera vendor, discusses what thermal imaging is, what problems power industry workers can identify with a thermal imaging camera (TIC), and the dangers of failure.
What is a Thermal Imaging Camera (TIC)?
A thermal imaging camera (TIC) is a contactless device that detects an object's heat signature. These devices create an image by converting infrared (IR) radiation into an image that is visible to the human eye. This process is called thermal imaging. Many professionals in the electrical utility sector use infrared cameras to analyze, identify, and display IR radiation data. This technology serves as a critical tool for predictive maintenance in power plants.
High-resolution options allow for inspection of components that are high off the ground. There are many TICs that an industrial electrician can mount to a drone for further analysis. What's particularly convenient is that maintenance professionals can perform TIC inspections without interrupting any operations, meaning no downtime. For instance, many inspectors use TICs to perform preventative maintenance and identify:
Electrical utility professionals can detect sulfur hexafluoride leaks in a turbine generator using a TIC. If left untreated, these issues in your transmission system can become massive environmental and downtime problems. TICs can also be used to find steam leaks in boilers, pipes, and valves.
The lost revenue from bushing failures can be overwhelming. By regularly inspecting them with a TIC, you can detect signs of bushing failure (i.e., insulation failure, tap changer failures) before the entire transformer goes down. Further, bushing failure often results in an explosion or a fire, contributing to significant property damage and employee injuries.
Avoid a widespread outage by inspecting insulators with a TIC. With the right IR solution, you can do this inspection from afar, eliminating the risk of putting workers in dangerous situations.
Load Tap Changer (LTC) Failure
Load tap changers regulate the output voltage of a transformer. If one fails, the entire transformer goes down as well. This issue can cost you millions of dollars between repairs and downtime. Using TIC, you can record and monitor temperatures and make mission-critical decisions about the condition of the LTC.
Regularly monitor transformer temperatures using a TIC to see hotspots, electrical resistance, and mechanical wear. Preventive maintenance of these critical distribution components will help you see issues that may lead to overheating and complete system failures before they happen.
Hotspots are a telltale sign of impending failure. However, you can catch distribution powerline problems early with a TIC. With a high-resolution solution, you can do this analysis right from the ground. Plus, with regular inspections, you can minimize the chances of costly outages and angry customers.
The Dangerous Cost of Failure
A common issue when distributing electricity is overheating due to transition resistance. Transition resistance occurs in defective electric conductors and resistors. These failed components may have been installed improperly by a power plant worker, they may be dusty or corroded, or have surface impurities.
This transition resistance creates heat loss. If power plants leave the issue unresolved, the temperature of the damaged resistor can cause a fire. In severe circumstances, the combination of fire and high voltage electricity can result in an electric arc (also known as an electrical flashover and arc flash). An electric arc is an irregular, high-voltage electrical discharge that flows through an air gap between conductors.
The Bureau of Labor Statistics found that between five and ten arc flash incidents occur in the United States every day. The consequences of an electric arc can be severe. Not only can it interrupt the end-users access to power, but it can also cause catastrophic injuries to workers, including:
Burns: Electrical arcs can reach temperatures of up to 34,000 degrees Fahrenheit (four times hotter than the sun).
Smoke inhalation: Staggering temperatures like those in electrical arcs can cause fires. The majority of fire-related deaths occur from smoke inhalation of toxic gases.
Arc blasts: Pressure waves follow the arc flash. These pressure waves launch fully grown adults across a room while also propelling melted metal, loose equipment and tools, and machinery through the air.
Hearing loss: Arc blasts are extremely powerful and cause a sound blast of up to 140db. This level of noise can cause temporary and even permanent hearing loss.
Eye damage: The debris from the arc blast can severely damage eyesight if it comes in contact with a worker's eyes. However, even if it doesn't, the ultra-violet light from the blast may also damage a worker's eyesight.
Searching for Partial Discharges
In order to provide consistent and safe access to power, utility companies need to inspect for partial discharge (PD) in their high voltage electrical equipment. PD is a localized electrical discharge that doesn't fully bridge the gap between two electrodes and/or conductors.
PD occurs regularly in power systems. However, it should only happen in components that manufacturers have built to handle it. It becomes an issue when there is a stressed part due to impurities, corrosion, and protrusions inside or around the insulation. These minor defects in the electrodes and conductors create a flurry of mini discharges which grow in number and intensity. Ultimately, PD can lead to equipment failure and an array of other catastrophic events such as:
Benefits of Thermal Camera Inspections
For industrial electricians, utility technicians, and transmission utility engineers inspecting for PD, high-end TICs can help them detect insulation failure safely. More specifically, using thermal technology allows professionals to:
Create a safer work environment
Increase product efficiency
Improve customer satisfaction
Provide reliable service
Reach out to TherCam
Minimize inspection times and ensure equipment reliability with TherCam’s thermal imaging products. Whether you’re maintaining essential components at power stations or troubleshooting issues, we offer a suite of IR solutions to help you identify problems before they happen. When you’re ready, browse our products and reach out today.