Next Generation Smart-Grid Enabled Electric Vehicle Chargers

在配电系统中(即在城市范围内)，太阳能光伏是目前占主导地位的可再生能源，但由于光照和遮阳条件的变化，其供电特性具有高度间歇性。此外，充电时插入配电系统的电动汽车也呈现出高度可变的负载。归根结底，电力公司的作用是为用户的所有负荷需求条件提供稳定交流频率的稳定电压。可再生能源的间歇性和电动汽车充电需求的多变性可能会给电力公用事业公司满足用户需求带来问题。智能电网技术，包括负荷管理和无功管理，是公用事业公司可以部署的潜在技术，以确保在电压调节方面可靠的电力输送。特别是利用电动汽车充电器对配电系统进行无功补偿，是一种新型的、潜在的极低成本和有效的配电网电压调节方法。为了实现这一目标，需要开发新的电动汽车充电技术，包括充电器的电源结构和控制策略。该研究计划的目标是展示用于智能电网配电系统的以无功注入为特征的新型交直流电动汽车电池充电技术。这项工作的功率水平将达到及超过3.3千瓦。该计划将针对三个关键领域的项目：i)将开发新的数字控制策略，以最大限度地减少失真，就像传统的功率因数校正一样，但也使可变相移输入能够允许无功功率注入电网。Ii)将为车载充电器开发一种新颖的紧凑型高效双向电池充电体系结构。Iii)为车载快速充电器开发了一种新颖的紧凑型高效双向电池充电结构。这项研究计划的长期目标是开发新技术，使电动汽车电池充电器能够增加配电系统的容量，以满足可再生能源发电和电动汽车数量的需求，而不需要昂贵的系统升级。

On the electrical distribution system (i.e. within city limits), solar photovoltaic is now the dominant renewable energy source, however it's supply characteristic is highly intermittent due to varied irradiant sun and shading conditions. In addition, electric vehicles, plugged into the distribution system when charging, also present highly variable loads. Ultimately, the role of the electrical utilities is to provide regulated voltage at regulated AC frequency for all load demand conditions from users. The intermittency of renewable power, and variability of electric vehicle charging demands can present problems for the electric utilities in meeting their requirements to users. Smart-grid technologies, including load management and reactive power management are potential techniques that utilities can deploy to ensure reliable power delivery in terms of voltage regulation. In particular, reactive power compensation to the electrical distribution system using electric vehicle chargers is a novel and potentially extremely low cost and effective method to regulate the distribution grid voltage. In order to achieve this goal, novel electric vehicle charging technologies, including charger power architectures and control strategies need to be developed. The objectives of the proposed research program are to demonstrate novel AC-DC electric vehicle battery charging technologies featuring reactive power injection for smart-grid electrical distributions systems. The work will be at power levels at and exceeding 3.3 kilowatts. The program will target projects in three key areas: i) Novel digital control strategies will be developed to minimize distortion, as in traditional power factor correction, but also enable variable phase shift input to allow reactive power to be injected to the electrical grid. ii) A novel compact and high efficiency bi-directional battery charging architecture will be developed for an in vehicle charger. iii) A novel compact and high efficiency bi-directional battery charging architecture will be developed for an off board fast charger. The long term objective of this research program is to develop novel technologies that enable electric vehicle battery chargers to increase capacity on the electrical distribution system for both renewable energy generation and the number of electric vehicles without requiring costly system upgrades.