Impact of a Stationary Energy Storage System in a DC Trolleybus Network

Abstract

In the context of urban transportation electrification, trolleybus systems can be modernized by using vehicles based on the so-called In-Motion-Charging (IMC) technology. The current required by IMC vehicles is higher than traditional trolleybuses because, in addition to traction, they must also absorb the current needed to recharge the batteries on board. With the aim of reducing voltage drops in trolleybus networks even in case of high-power demands, the impacts of the inclusion of a mid-line stationary energy storage system to maintain a high voltage level and to reduce the network energy losses are analyzed in this paper. This work consists of the development of Monte Carlo-based simulations to treat as random variables the initial positions of the trolleybuses in the DC catenary system and their respective current draws. A current absorption profile of the IMC trolleybus has been used in conjunction with a model able to simulate the movement of multiple vehicles in a DC network section. According to the achieved results, it is possible to observe an improvement in the network voltage profile and an indication of energy savings.