复合储能电动车能量馈网稳定性分析

Stability Analysis of Energy Feedback Grid-connected of Composite Energy Storage Electric Vehicle

针对传统复合储能电动车系统并网过程中能量通常由电池组单一提供问题,设计了一种新型能量回馈并网系统,优化电池组输出大电流能力,延长储能系统的使用寿命。分析了新型能量回馈并网系统的结构和工作原理。对电池组和超级电容器进行了具体的数学建模,通过能量管理策略,实现了电动汽车作为储能终端的可变功率并网要求。逆变器采用VSG技术作为控制策略,使其在整个大系统中虚拟为同步发电机。整个系统保证能量传输的可靠性,并自动实现合理的功率分配,实现了对不平衡功率的快速补偿和储能荷电状态的调整。它可以模拟同步发电机的惯性和阻尼特性,克服传统的无惯性连接的逆变器对电网的影响,可以有效地提高电网接受可再生能源的能力。最后通过仿真模型验证了该控制方法的可行性和有效性。研究成果可为新能源电动车并网系统安全控制提供参考。

Aiming at the problem that the energy of the traditional composite energy storage electric vehicle system is usually provided by the battery pack,a new energy feedback grid-connected system is designed to optimize the output current capacity of the battery pack and prolong the service life of the energy storage system.The structure and working principle of the new energy feedback grid-connected system are analyzed.The specific mathematical modeling of the battery pack and supercapacitor,through the energy management strategy,realizes the variable power grid connection requirements of the electric vehicle as the energy storage terminal.The inverter uses VSG technology as a control strategy,making it a synchronous generator in the entire large system.The whole system guarantees the reliability of energy transmission and automatically realizes reasonable power distribution,realizing rapid compensation of unbalanced power and adjustment of energy storage state.It can simulate the inertia and damping characteristics of synchronous generators,overcome the influence of traditional inertia-connected inverters on the grid,and effectively improve the grid′s ability to accept renewable energy.Finally,the feasibility and effectiveness of the control method are verified by simulation model.The research results can provide reference for the safety control of grid-connected systems for new energy electric vehicles.