中文摘要：

交直流混联配电系统的稳定性分析方法是评价系统能否安全稳定运行的关键技术。传统稳定性分析方法通常以直流级联系统和直流微电网作为研究对象,而对于含恒功率负载的交直流混联配电系统稳定性分析和评价较少涉及。基于这一问题,提出了适用于交直流混联配电系统的阻抗匹配稳定性分析方法,建立了柔性互联装置、光伏发电单元、恒功率负载以及？型线路的状态空间小信号模型。在多端柔性互联装置采用主从和下垂控制情况下构建了交直流混联配电系统的戴维南等效电路,利用奈奎斯特稳定判据确定了负阻抗稳定边界,并且采用Simulink仿真工具搭建了详细物理模型,通过仿真结果和奈奎斯特曲线对比分析验证了所提稳定性分析方法的可行性。

英文摘要：

The stability analysis method of AC/DC hybrid distribution system is the key technology to evaluate whether the system can operate safely and stably. Traditional stability analysis methods are usually based on the DC cascade system and DC microgrid as the research object, and the stability analysis and evaluation of AC/DC hybrid distribution systems with constant power loads are rarely involved. Based on this problem, the stability analysis method based on impedance matching was proposed for AC/DC hybrid distribution system, state space small signal model of flexible interlinking device, photovoltaic power generation unit, constant power load and line were established. Thevenin equivalent circuits of AC/DC hybrid distribution system were established when the master-slave control and droop control were used for multi-terminal flexible interlinking device. The negative impedance stability boundary was determined by the Nyquist stability criterion, and the detailed physical model was built by the Simulink simulation tools. Finally, the feasibility of the proposed stability analysis method was verified by comparison analysis of simulation results and the Nyquist curves.