无线充电电动汽车V2G模式下光储直流微电网能量管理策略

Research on Power Management Strategy of DC Microgrid with Photovoltaic, Energy Storage and EV-Wireless Power Transfer in V2G Mode

随着电动汽车数量与负荷的激增,构建实现低碳、灵活、稳定的电动汽车充电方式至关重要。该文融合直流微电网以及无线电能传输、车网互联(V2G)等技术,重点研究无线充电电动汽车V2G模式下光储直流微电网能量管理策略。分别建立光伏、无线充电电动汽车、网侧储能数学模型。考虑光伏出功与负载状态,推导无线充电电动汽车最优效率馈网的临界条件,给出超出临界点后网侧储能的出力函数。基于此,定义直流微电网三种运行模式及其边界条件,设计上层控制器实现三种模式间的切换。搭建实验系统,验证不同负荷下所提出的分层控制算法可有效维持母线电压稳定,并且保持光伏系统的最大功率与无线电能传输系统的最优效率运行。

With the rapid increase of electric vehicles(EVs),it is essential to build a low-carbon,flexible and stable charging method for EVs.This paper integrated DC microgrid,wireless power transfer(WPT),vehicle-to-grid(V2 G)technologies,and focused on the power management strategy of DC microgrid with photovoltaic,energy storage and WPT system in V2 G mode.The mathematical models for photovoltaic,WPT,and energy storage were established,respectively.Considering the photovoltaic power output and the load power level,the critical conditions for the WPT system under maximum power efficiency status were derived,and the output function of the energy storage beyond the critical conditions was given.Based on this,the three operating modes and boundary conditions of the DC microgrid were defined,the upper-level controller was designed to switch between the three modes.An experimental system was constructed to verify that the proposed hierarchical control algorithm can effectively maintain the stability of the bus voltage.The maximum power of the photovoltaic system and the optimal efficiency operation of the WPT system were also guaranteed.