A Holistic Approach to Plan Wireless Charging Stations in an Electric-Transportation Nexus

Abstract

Wireless charging principles enable electric vehicles (EVs) to charge wirelessly in three different ways—static, dynamic, and quasi-dynamic—using wireless power transfer (WPT) technology other than charging cables. In quasi-dynamic charging (QWC) systems, the EVs charge as they stop for brief periods in traffic or bus stops during their journeys. In this thesis, a mathematical optimization model for the optimal siting of QWC stations in road and power networks is presented. The problem is formulated as a mixed integer nonlinear programming (MINLP) model. The objective of this optimization model is to optimally determine the sites for QWC stations that will minimize investment costs of power transmitter installation. Furthermore, four different optimization algorithms are implemented to solve the problem. The developed optimization model and the optimization algorithms are implemented and solved using MATLAB. The results from these algorithms are presented and compared. A battery capacity of 10 kWh is determined to be the most suitable battery capacity for the bus fleet. The total power transmitter length that complements this battery size is also realized to be 323.2 m, divided between six different bus stop areas. Furthermore, an optimization model for the sizing of a PV and a BESS system is presented to supply the load requirements of the electric bus fleet in an off-grid case. First, a bus schedule is made for the buses within the fleet to ascertain the number of buses that pass through a bus stop and thus, a power transmitter each hour. Then, the energy demand of the bus fleet in the charging stations is computed. The load demand by the bus fleet per hour in several scenarios serves as an input to the developed optimization model. The results show that a PV with a rated power of 394.173 kW and a BESS of about 2000 kWh is needed to meet the energy needs of the bus fleet throughout the day. The main contribution of this work is to optimally site a QWC system in both a road and power network. Although other models have sited QWC systems in road networks, to the best of the author’s knowledge, a coupled road and power network for QWC systems have not been implemented in literature. Another contribution of this thesis is to test the most efficient algorithms to solve the coupled road-power network for the developed QWC optimization problem. Furthermore, this work also provides an approach to meet the charging demands of wireless charging EVs through a PV-BESS model taking into consideration the travel schedule of electric buses traveling along a bus route.

Date of Award	Apr 2023
Original language	American English