中压配电网柔性互联示范工程技术方案设计

结合东莞松山湖地区中压配电网的实际问题和工程示范规划,对中压柔性直流互联在该地区中压配电网中的应用方案进行研究。对系统的主接线方式、联接变压器配置和接地方式进行了论证;对系统中模块化多电平换流器和电力电子直流变压器进行了初步设计,确定了关键设备主要技术要求;仿真分析了系统过电流和过电压特性,提出了系统的过流耐受和绝缘配合要求;设计了系统总体控制架构和保护配置,明确了系统的控制保护策略。文章对示范工程所采用的新型主回路拓扑进行了论证,提出并采用了高纹波紧凑化的设备设计方案,提出了交流故障协调响应策略,并对这些新技术进行了论证和仿真验证,可为后续相关研究和工程实践提供参考。

Technical Scheme Design of an MVAC Distribution Network Project for Demonstration with MVDC-Flexible Interconnection

Combined with the actual problems of the medium-voltage (MV) AC distribution network in Songshan Lake area of Dongguan, the technical scheme of an MVAC distribution network project for demonstration with HVDC-flexible interconnection is studied. The main wiring mode, connection transformer configuration and grounding mode are demonstrated. The modular multi-level converter and power electronic DC transformer in the system are preliminarily designed, and the technical requirements for key equipment are determined. The system overcurrent and overvoltage characteristics are analyzed by simulation, thus overcurrent tolerance and insulation coordination requirements being put forward. The overall control architecture and protection configuration of the system are designed, and the control and protection strategy of the system is defined. The new main connection topology proposed in this article is used in a practical demonstration project. The scheme of high-ripple design for compact equipment is adopted and the AC fault coordination response strategy is proposed. All those new technologies are demonstrated and verified with simulation, which provide reference for follow-up related research and engineering practice.