Energy storage for enhancing transmission capacities and trans-regional reserves of a UHV AC/DC power grid

This paper concerns the use of energy storage for enhancing transmission capacities and trans-regional reserves of a UHV AC/DC power grid. First, based on the correspondence of power shortage to frequency variation in the receiving system of UHV AC/DC power grid, this paper proposes a model on capability improvement of the receiver and capacity allocation of storage while maintaining the stability of the minimal frequency scenarios. Second, through the analysis of the load characteristics of different intervals during typical days, a model between increasing renewable generation and required capacity of storage for peak shaving is also proposed. Third, considering both the fault support and trans-regional peak shaving reserve as well as their priorities, the capacity configuration and the associated economic feasibility are studied. Finally, verification of the method is done by a simulation which sets Henan Grid as the weak receiving end while Xinjiang Grid as the sending end abundant in renewable energy.