Load Balancing of a Modular Multilevel Grid-Interface Converter for Transformer-Less Large-Scale Wireless Electric Vehicle Charging Infrastructure
Load Balancing of a Modular Multilevel Grid-Interface Converter for Transformer-Less Large-Scale Wireless Electric Vehicle Charging Infrastructure
复制标题
用于无变压器大型无线电动汽车充电基础设施的模块化多级电网接口转换器的负载平衡
DOI：
10.1109/jestpe.2020.3043211
复制
发表时间：
2021
影响因子：
5.5
通讯作者：
J. Suul
中科院分区：
文献类型：
--
作者：
G. Guidi;S. D'arco;Koudai Nishikawa;J. Suul
本文分析了大规模电动汽车（EV）充电基础设施的新型无变压器电网接口拓扑的负载平衡要求。所提出的配置利用模块化多电平转换器（MMC）从每个模块提供无线EV充电器。无线感应电力传输提供的固有电流隔离和MMC拓扑的可扩展性使无变压器连接到中压（MV）配电网成为可能。这可以减少停车基础设施内部配电的占地面积和铜体积。MMC拓扑内的负载分布取决于待充电的每个EV的位置和功率要求。负载平衡的要求，通过控制内部循环电流的拓扑结构时，提供不均匀分布的负载。它还演示了如何可以利用循环电流的二次谐波分量，以确保每个MMC臂内的平衡能力，以及它所需的幅度取决于负载分布。理论分析和相应的控制策略的性能首先验证了一个大型基础设施的时域仿真。实验结果从一个小规模的原型MMC的基础上，每个手臂有12个模块与个别可控负载。
This article analyzes the requirements for load balancing of a new transformer-less grid-interface topology for large-scale electric vehicle (EV) charging infrastructures. The proposed configuration utilizes a modular multilevel converter (MMC) to supply wireless EV chargers from each module. The inherent galvanic isolation provided by wireless inductive power transfer and the scalability of the MMC topology enable transformer-less connection to medium voltage (MV) distribution grids. This can reduce the footprint and copper volume of the internal power distribution for the parking infrastructure. The load distribution within the MMC topology depends on the location and power requirements of each EV to be charged. Requirements for load balancing by controlling the internal circulating currents of the proposed topology when supplying unevenly distributed loads are derived. It is also demonstrated how a second harmonic component of the circulating currents can be utilized to ensure balancing capability within each MMC arm, and how its required amplitude depends on the load distribution. The theoretical analysis and the performance of a corresponding control strategy are first verified by time-domain simulations of a large-scale infrastructure. Experimental results from a small-scale prototype based on an MMC where each arm has 12 modules with individual controllable loads are presented.