Application of fixed and mobile battery energy storage flexibilities in robust operation of two-way active distribution network

Abstract

The use of flexibilities in the electricity distribution network is aimed at achieving more optimal operation of this network. One of the methods of using flexibility is using energy storage systems. In the operation of the distribution network with variable tariff, energy storage systems create flexibility in the network by charging in off-peak hours and discharging in peak hours. Batteries, which are the most widely used storage systems in the electricity distribution network for the operation of this network, are divided into two categories: fixed and mobile batteries. In fixed batteries, the installation location of the battery is already known, but in mobile batteries, the battery is transported on a truck and its location changes according to the operation, which is spatial-temporal flexibility of mobile batteries, and their location is determined according to the parking lots created to stop the truck. In this paper, the formulation of two-way distribution network operation in the presence of fixed and mobile batteries is presented. In the presented formulation, firstly, the model of fixed and mobile batteries is presented, and then it is aggregated in the problem of operation of two-way distribution network. The spatial-temporal flexibility of a mobile battery is a feature that allows for various applications. Unlike a fixed battery that only has temporal flexibility, in a mobile battery both temporal and spatial flexibility exist and are formulated. In the presented model, the robust optimization method is used to model the uncertainties of the problem. Finally, simulations on the IEEE 33-bus network have been presented to prove the capability of the presented model and the flexibility used. Considering 4 general states without fixed and mobile batteries, despite the fixed battery, despite the mobile battery and despite simultaneous both types of fixed and mobile batteries, in 3 cases, feeding from bus 1, feeding from bus 33 and feeding from both sides, the indices of the objective function value of the problem, the apparent power peak of the network and the active power losses have been investigated, which shows the effectiveness of using the flexibility mentioned in this paper. The value of the objective function, active power losses, and the apparent power peak of the network by using both types of storage devices in the network from both sides of supply has been reduced by 12, 70, and 13 percent, respectively, compared to the case where none of the storage devices were used.