柔性直流电网的继电保护与故障定位新原理研究

项目名称： 柔性直流电网的继电保护与故障定位新原理研究

项目编号： No.51477131

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 电工技术

项目作者： 宋国兵

作者单位： 西安交通大学

项目金额： 75万元

中文摘要： 柔性直流输电在海岛供电、新能源接入系统和城市配电网等领域具有广阔应用前景，直流断路器的商用化将加速直流电网的形成。柔性直流输电采用电压源换流器方式，故障时电容放电会产生大的短路电流，且短路电流与电网规模和故障持续时间有关。为了快速隔离故障、减少故障分支对健全电网的影响，同时减小故障电流对直流设备和直流断路器造成的冲击，研究超高速与高可靠性相结合的直流电网继电保护新原理，对于保障直流电网的安全可靠运行意义重大。继电保护反应故障特征而动作，而直流系统故障特征又取决于其拓扑结构与控制特性，故本项目拟建立计及拓扑结构和控制特性的直流电网故障特征理论分析体系，系统地提出基于拓扑结构的直流电网单端电气量快速主保护与故障定位新原理、基于控制特性的直流电网后备保护新原理、以及利用多端电气量的高灵敏后备保护新原理。本项目的研究为柔性直流电网的安全可靠运行提供完备的继电保护理论基础。

中文关键词： 柔性直流电网；继电保护；故障定位；拓扑结构；分布参数

英文摘要： HVDC Flexible power transmission systems have bright future in island power supply systems, new energy power supply systems, distribution systems of the central cities and other fields. The commercialization of the DC circuit breaker will promote the development of multi-terminal HVDC and HVDC grids. The HVDC Flexible systems are based on Voltage Source Converter, and with huge capacitors in parallel at the terminals of the transmission lines. So,the convertor stations will provide remarkable current when faults occur on the DC transmission lines. And the current of faults is closely related to the scale of the grids and the time of fault duration.In order to isolate faults rapidly, to reduce faults influence on the operation of the remanent DC power grids, and to minimize the current impact on DC equipments and circuit breakers, it is necessary to study the theories and strategies of ultra high-speed and reliable protections, and they will have important influence on security and stability of operation of DC girds. Relay protections operate according to the fault characteristic, which depends on the topology structures and control characteristics of the HVDC Flexible transmission system. Thus, this project proposes to systematically analyse fault characteristic by considering the effects of topology structures and control characteristics of the DC power transmission system. Then the quick-action non-communication protections and fault location principles based on the topological structure of the DC transmission system, back up protections based on the control characteristics of the DC power transmission systems, and the high sensitive pilot protection principles using multi-terminal electrical quantities will be presented in this project. Moreover, the research works will provide perfect theoretical basis and technical support for the secure and reliable operation of HVDC flexible power transmission systems.

英文关键词： Flexible HVDC;Relaying protection;Fault location;Topological structure;Distributed parameter