The Role Gas Turbines Play in Power Plant Reliability

Gas turbines play a huge role in power plant reliability. In most cases—whether it be simple-cycle or combined-cycle applications for gas turbines—the gas turbine is the first major piece of equipment in the process that needs to start. So, without a reliable control system or a well-maintained and cared-for control system, your primary piece of major equipment is out of the game or unavailable.

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In this article, we will explain the role of gas turbines a little more, and why they so important for the reliability of your power plant.

Start Permissives: Ready to Start or Not?

Typically, when most frames 7FA, 6FA, 5A, or any industrial frame size gas turbine owner starts the plant with the gas turbine control system, there is typically a page with start permissives, indicating the system is ready to start or not ready to start. Start permissives are conditions on the unit that need to be met before it can start.

In many cases, the rest of the equipment at the plant depends on the gas turbine control system because it is often the first thing that plant managers will start before the other equipment. 

Therefore, if you receive the “not ready to start” indication, then you won’t be able to start your gas turbine—or the rest of your plant at all, especially if there are other drivers behind the gas turbine. 

How the Control System Works

A control system is made up of a bunch of subsystems, pretty much like everything in a power plant. So, the control system as a whole has subsystems under it, and that can kind of be broken down and analyzed in an engineering mind state. 

The primary parts of the control system are the software and logic, which are really reliable. They don’t typically break; they are just computer code that is programmed.

Typically when we see problems, malfunctions, abnormalities in logic or software, it’s because of some type of human interaction. Most control systems or any other equipment for that matter don’t fail on their own. Of course, failures without human interaction can happen, but they are rare.  

The relays in the system that bring the logic from the software are typically control cards and other communication devices. These devices can fail. In these cases, when the devices can fail, the logic and software fails as well.

Why Reliability is So Important

If you don’t have a reliable gas turbine control system, then you usually can’t even get the plane off the ground, so to speak. You can’t even really gain any momentum!

Therefore, it is important to perform check out and regular inspections of your control system equipment. At TC&E we like to call these inspections “reliability assessments”. To put it simply, it involves a clean and inspect of the system. 

At TC&E, our team checks the control system, cleans it out, performs some file management, and ensures that there aren’t any warning lights and that everything looks healthy and functional.

Contact our team today to learn more about our reliability assessments and what we can do to help ensure your plant’s reliability.