Stress-informed control of medium- and high-head hydropower plants to reduce penstock fatigue

The displacement of conventional generation in favor stochastic renewable requires increasing regulation duties from the remaining dispatchable resources. In high- and medium-head hydropower plants (HPPs), providing services to grid frequently changing plant’s set-point causes water hammer, which engenders pressure stress transients within pressurized conduits, especially penstock, damaging it long run. This paper proposes a model predictive control (MPC) that explicitly models hydraulic penstock. It achieves reduce mechanical loads on penstock wall, and, consequently, fatigue effectively. Thanks suitable linearization plant model, optimization problem underlying MPC scheme is convex can be solved with off-the-shelf libraries. performance proposed controller tested numerical simulations 230 MW HPP Francis turbine primary frequency control. Simulation results show substantially reduced fatigue, existing approaches outperformed, resolution times compatible real-time requirements.