Impact of two-way communication of traffic light signal-to-vehicle on the electric vehicle state of charge

Abstract

Given the ongoing concerns on the emissions of greenhouse gases that contribute to global warming, the electric vehicle is considered as a promising technology solution for the reduction of these emissions in the transportation sector. Despite the numerous advantages of electric vehicles, the limited driving range is one of the prominent drawbacks that need to be addressed. Since the driving range is related to the battery's state of charge, which is, in turn, related to power consumption, there is a need to minimize the vehicle power consumption. Increased speeds and accelerations lead to a decrease of the state of charge. In this paper, we utilized vehicular networks that allow traffic light signals to communicate with approaching vehicles to avoid unnecessary high speeds and accelerations at an isolated intersection. This communication can be bidirectional, that is, from the vehicle to the traffic light signal, and vice versa. This enables the traffic light signal to adapt its green duration according to vehicular information and then send back its information to vehicles that in turn adapt their speeds based on the received information. We propose an optimization model that determines the optimum green duration and optimum vehicular speed, which ensures that the vehicle will cross the traffic light signal with maximum battery's state of charge. The analytical results indicate that the proposed approach which is adaptive in both speed and traffic light signal can achieve an improvement of the state of charge compared to other two approaches, which are adaptive in either speed or traffic signal.