Steam turbines are central components in fossil fuel and nuclear power plants, and in certain industrial plants as well. Therefore, steam turbines must be as efficient, dependable and safe as reasonably possible. A major turbine accident can cause serious damage to the turbine itself, the plant and even personnel. The safety functions realized in the turbine control system and the protection system are crucial to avoid such events. The scope of my thesis is the steam turbine protection system, and its co-operation with the control system.
In the first part of my thesis, I explain the operating principle of steam turbines. I describe the configuration and the operation of the control system and the protection system in detail. I introduce Siemens SIMATIC PCS7, which is a distributed control system (DCS) capable of handling industrial size steam turbines.
In the second part I present how I carried out my task, which was to add new functions to the protection system of an industrial steam turbine. I implemented these hardware and logic changes in a SIMATIC PCS7 project. I updated the HMI accordingly. Finally, I tested the software modifications in a laboratory environment.