低压交直流混合配电系统线性化建模方法

线性化模型是直流系统稳定性分析、接口耦合机理研究及控制器设计的基础。将含多直流微网的辐射状交直流混合配电系统分为整流接口及所连交流主网、逆变接口及所连无源交流系统、并网接口及所连直流微网以及直流网络4个部分,建立灵活的同步旋转坐标系。分别推导系统各部分在发生小扰动下的暂态数学模型。采用一种含控制标识位的接口控制器线性化建模方法,并引入锁相环控制,建立系统的全局线性化模型,提高了模型在不同应用场景下的普适性。通过与电磁暂态模型进行对比分析,验证了所建立的交直流混合配电系统全局线性化模型的正确性和有效性。

A linearized modeling method of low voltage hybrid AC and DC distribution system

The linearization model is the basis of stability analysis, interface coupling mechanism research and controller design for DC power system. A radial hybrid AC and DC power distribution system with multiple DC micro-grids is divided into 4 parts, including rectifier interface and the AC main network, inverter interface and the passive AC system, the grid-connected interface and DC micro-grids, and the DC network. The transient mathematical models of each part of the system under small perturbations are respectively deduced through establishing a flexible d-q synchronous reference frame. In order to improve the universality of the model in different application scenarios, a linearized modeling method of the interface controller with control identification bits and the phase locked loop control are introduced to establish a global linear system model. By comparing with the electromagnetic transient model, the correctness and validity of the global linear model of the hybrid AC and DC distribution power system are verified. This work is supported by National Natural Science Foundation of China (No. 51677023).