一种基于虚拟电机控制的能量路由器

An Energy Hub Based on Virtual-Machine Control

能量路由器是能源互联网的关键技术之一,其电路拓扑和运行控制与可再生能源接纳、灵活电力变换息息相关。与传统基于固态变压器的能量路由器不同,文中提出一种交直流混合、工频隔离、交直流模块化的能量路由器电路,便于低压交直流配电网接入、负荷供电、可再生能源和储能等分布式电源消纳。在此基础上,基于虚拟电机理论,还提出该能量路由器的控制策略,交流侧接口采用虚拟同步电机控制,直流侧接口采用虚拟直流电机控制,以增强系统惯性和阻尼,提升系统稳定性。然后,建立了虚拟电机控制的数学模型,分析其小信号模型和功率分配特性。最后,针对一个典型的能量路由器系统,利用PSCAD/EMTDC的仿真结果验证了所提电路拓扑和控制策略的正确性和有效性,为能量路由器和能源互联网的研究提供了一种新的模型和方法。

The energy hub is one of the key technologies under the umbrella concept of energy internet. The energy hub topology and its control scheme will closely affect the flexible operation of future grids in terms of conversion and renewable integration. An AC/DC hybrid electric energy hub was proposed with a modular structure and isolation on the line-frequency AC side. Using the hub,the low voltage AC and DC distribution networks,renewable energy sources,energy storage devices and loads can be easily integrated into the utility system. A virtual-machine-based control strategy was presented for the energy hub to emulate the machine inertia and damping,improving its stability. Based on the study using established models and a virtual-machine-based control scheme,a small-signal model and power sharing scheme of the energy hub were proposed. Finally,focusing on a typical energy hub system,the validity and effectiveness of the proposed topology and control strategy are verified by using PSCAD/EMTDC. The proposed model and analysis approach can be useful in future energy internet and energy hub development.