交直流混合配电网分布式电源最大准入容量

文章在负荷频率控制（load frequency control，LFC）相关技术基础上，针对孤岛模式下互联微电网（micro-grids，MG）组成的电力系统，提出新的广义动态LFC模型、鲁棒分散式LFC控制策略。首先，描述单区域、多区域控制系统的LFC机制，将经典的LFC方法应用于运行场景多变、孤岛模式下互联MG组成的电力系统中。然后，针对孤岛模式下互联MG组成的电力系统，提出一种基于一致性协同控制策略的LFC算法，该算法通过控制调速器-涡轮的输入及管理储能系统（energy storage systems，ESS）向MG中注入或吸收的功率量，实现孤岛MG的自适应同步频率控制。其次，阐明饱和约束下的ESS可以有效地减轻小惯性和小阻尼在MG中引起的不稳定现象。最后通过搭建孤岛模式下6个互联MG组成的电力系统仿真模型验证该算法的正确性与有效性，所得到的控制器能够使干扰的影响最小化并保持鲁棒的性能。

Maximum Capacity of Grid-Connected Distributed Generation in AC/DC Hybrid Distribution Network

The proportion of distributed generation（DG） in the distribution network is continuously increasing， which has a certain impact on the normal operation of distribution network. It is necessary to evaluate the maximum access capacity of the distributed generation. The operation mode of AC/DC hybrid distribution network is more flexible than the traditional AC distribution network. The AC/DC hybrid distribution network has a larger acceptability of the distributed generation and it is the development trend of the distribution network in the future. This paper constructs the maximum capacity evaluation model of distributed generation for AC/DC hybrid distribution network on the basis of Distflow power flow constraint， and then the second-order cone relaxation technique is used to deal with the non-convex and nonlinear constraints in the model. The model is transformed into a solvable mixed integer second-order cone programming model to be solved. Finally， the effectiveness of the model is tested in a 94-node distribution system. The maximum access capacity of the distributed generation and the corresponding influencing factors of the AC distribution network and the AC/DC hybrid distribution network are also analyzed. The results show that the maximum access capacity of the distributed generation in AC/DC hybrid distribution network is larger than that of the traditional AC distribution network.