Determining the emergency capacity of the upper reservoir for black-start in a pumped storage plant

When a pumped storage plant is used for black-start in system restoration, some capacity in the upper reservoir must be reserved. However, this capacity cannot be used for load-balancing in daily operation. Obviously, the economy of pumped storage plant would be influenced. So it is significant to make reasonable evaluation of black-start capacity of the upper reservoir. In order to address this problem, a methodology from the perspective of energy conservation is first proposed in this paper. Furthermore, according to a specific black-start plan, this paper gives an algorithm to obtain the electricity energy consumed in the black-start procedure. Accordingly, the black-start capacity can be attained by the relation between the potential energy and the electricity energy. An example from a practical black-start test can be used to verify the feasibility of this algorithm.