French
English
The growing demand for increased flexibility in modern power systems poses a significant challenge to the safe operation of hydropower assets. The extended operating ranges and frequent start-ups and stops, necessary for regulating services to the power grid, lead to performance degradation and reduce the lifespan of hydropower equipment. This seminar addresses this challenge by discussing which technologies can be leveraged and how to achieve their optimal implementation in refurbished hydroelectric units to improve the flexibility of hydropower plants by mitigating the impact on the lifetime of the mechanical component.
Delving into the next frontier for hydropower, the discussion highlights innovative methods based on experimental investigations, analytical modelling and AI integration to exploit variable speed and hybridization with batteries by minimized fatigue and wear of the legacy equipment. Experimental investigations using strain gauge measurements on reduced-scale models help develop predictive models considering the full operating range and severe transient operations, offering a breakthrough in understanding fatigue-induced damage and aging. As an example, the results indicate a significant reduction in start-up-induced fatigue by using variable-speed: Francis turbines potentially experience a 90% reduction in runner fatigue by avoiding high-stress operating conditions during start-up.
Elena Vagnoni
Research Associate, École Polytechnique Fédérale de Lausanne