Autonomous Mobility and Energy Service Management in Future Smart Cities: An Overview

With the rise of transportation electrification, autonomous driving and shared mobility in urban mobility systems, and increasing penetrations of distributed energy resources and autonomous demand-side management techniques in energy systems, tremendous opportunities, as well as challenges, are emerging in the forging of a sustainable and converged urban mobility and energy future. This paper is motivated by these disruptive transformations and gives an overview of managing autonomous mobility and energy services in future smart cities. First, we propose a three-layer architecture for the convergence of future mobility and energy systems. For each layer, we give a brief overview of the disruptive transformations that directly contribute to the rise of autonomous mobility-on-demand (AMoD) systems. Second, we propose the concept of autonomous flexibility-on-demand (AFoD), as an energy service platform built directly on existing infrastructures of AMoD systems. In the vision of AFoD, autonomous electric vehicles provide charging flexibilities as a service on demand in energy systems. Third, we analyze and compare AMoD and AFoD, and we identify four key decisions that, if appropriately coordinated, will create a synergy between AMoD and AFoD. Finally, we discuss key challenges towards the success of AMoD and AFoD in future smart cities and present some key research directions regarding the system-wide coordination between AMoD and AFoD.Comment: 19 pages, 4 figure

Design, analysis and control of DC/DC converter based DC wind farms

This thesis discusses the design, operation and control of DC wind farms that use high power DC/DC converters, DC cables and DC collection networks. DC wind farms are proposed as alternatives to traditional AC wind farms due to the potential to reduce the system size, improve the speed of dynamic response and improve the system efficiency. DC wind farms involve different types of high-power DC/DC converters in different stages of power conversion. Isolated DC/DC converters are chosen as the wind turbine converters in which the intermediate transformer design is of great importance. A general and comprehensive medium frequency transformer modelling and design methodology is presented in this thesis, which considers the efficiency, leakage inductance and thermal management. The proposed methodology is applied to transformers for single phase and three phase DC/DC converters. Isolated Single Active Bridge DC/DC converters are appealing topologies for medium voltage applications. The operation of these DC/DC converters is complex and important for the converter control design. The comprehensive operational principles of three-phase single active bridge converters under changing duty cycle are investigated. Eight operating modes are identified with detailed derivation of power flow and current dynamics. The converter performances are evaluated and compared theoretically and experimentally. Then, the control of wind turbine converters in DC wind farms is designed considering both DC-link and network dynamics. To deal with the oscillations caused by smoothing reactors, a power system stabilizer based control design is developed and implemented. Furthermore, a multi-variable feedback control design using pole-placement technique is proposed. This method is able to achieve the minimum oscillatory time without compromising the dynamic performance of the DC-link voltage. Finally, taking into account the low capacitance issue in wind farms, the voltage stability of DC wind farms is investigated and different stabilizing methods are designed and analyzed. The impedance models of aggregated wind turbine converters, DC cables and the station DC/DC converter with control action are derived, in order to study the interactions between the station converter and the DC wind farm. A new equivalent capacitor control strategy to enhance the system capacitance is proposed and analyzed through various case studies.Open Acces

Practical applications of multi-agent systems in electric power systems

The transformation of energy networks from passive to active systems requires the embedding of intelligence within the network. One suitable approach to integrating distributed intelligent systems is multi-agent systems technology, where components of functionality run as autonomous agents capable of interaction through messaging. This provides loose coupling between components that can benefit the complex systems envisioned for the smart grid. This paper reviews the key milestones of demonstrated agent systems in the power industry and considers which aspects of agent design must still be addressed for widespread application of agent technology to occur

Open-Source, Open-Architecture SoftwarePlatform for Plug-InElectric Vehicle SmartCharging in California

This interdisciplinary eXtensible Building Operating System–Vehicles project focuses on controlling plug-in electric vehicle charging at residential and small commercial settings using a novel and flexible open-source, open-architecture charge communication and control platform. The platform provides smart charging functionalities and benefits to the utility, homes, and businesses.This project investigates four important areas of vehicle-grid integration research, integrating technical as well as social and behavioral dimensions: smart charging user needs assessment, advanced load control platform development and testing, smart charging impacts, benefits to the power grid, and smart charging ratepayer benefits

A review of modular electrical sub-systems of electric vehicles

Climate change risks have triggered the international community to find efficient solutions to reduce greenhouse gas (GHG) emissions mainly produced by the energy, industrial, and transportation sectors. The problem can be significantly tackled by promoting electric vehicles (EVs) to be the dominant technology in the transportation sector. Accordingly, there is a pressing need to increase the scale of EV penetration, which requires simplifying the manufacturing process, increasing the training level of maintenance personnel, securing the necessary supply chains, and, importantly, developing the charging infrastructure. A new modular trend in EV manufacturing is being explored and tested by several large automotive companies, mainly in the USA, the European Union, and China. This modular manufacturing platform paves the way for standardised manufacturing and assembly of EVs when standard scalable units are used to build EVs at different power scales, ranging from small light-duty vehicles to large electric buses and trucks. In this context, modularising EV electric systems needs to be considered to prepare for the next EV generation. This paper reviews the main modular topologies presented in the literature in the context of EV systems. This paper summarises the most promising topologies in terms of modularised battery connections, propulsion systems focusing on inverters and rectifiers, modular cascaded EV machines, and modular charging systems