The thesis deals with turbine controller for small hydro power plants with synchronous generator. Turbine controller maintains the set point which depends on selected mode of hydro machine operation. To achieve this it controls opening of governor, runner blades or needles and deflector, depending on turbine type.
Turbine controller algorithm was implemented on programmable logic controller and consists of the following parts: speed controller which acts during the free run, level controller, load controller, opening controller and frequency controller when the hydro machine is connected on the electric grid. The frequency controller is used when the power plant is connected to islanded electric grid.
For turbine controller design a mathematical model of hydropower plant was developed. It consists of five sub-models: the model of upper reservoir, the penstock model including the water hammer effect, the turbine model, the model of hydraulic solenoid valves and servomotors and the simplified model of synchronous generator. Data communication between model and turbine controller is realized with Ethernet connection using S7 protocol. Using the model the control algorithms were designed and tested.
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