Economic and technical aspects of adjustable speed hydro (ASH) machines applied for improved stability in power networks

This paper presents the adjustable speed hydro (ASH) machine concept as an alternative to traditional ways for obtaining better utilisation of power systems. Transmission lines appearing as bottlenecks with respect to power demand may increase their transfer capacity as ASH machines are introduced in the network. The paper has given a quantification of how much the power export out of an example region can be increased due to introduction of ASH machines in the production system. This is valuable not only for the power producer but also for the system operator and for community due to an improved utilisation of the network infrastructure. In turn, this may lead to a postponement of high investment costs for new overhead lines