基于分层分区原则的大机组接入系统的电网规划

我国电网发展已经进入大区电网互连、跨大区电网输电的格局，加强受端系统的网络对全局的电网运行有着重要的意义．受端系统电网规划中，大机组接入系统的电压等级选择关系到对受端系统的电源、电压支撑，也和受端系统内部电网的实际运行情况密切相关．文中从规划工作的实际经验出发，分析了大机组接入500kV电网的优点和必须注意的问题，并通过事例说明了如何应用简化电厂接线、分散外接电源、分层分区接入的原则确定大机组接入系统电压等级．

Power Network Planning of Large-Scale Units Accessed to Power Systems Based on Layers and Zones

The development of power network in China has entered the new stage of bulk power network interconnection and trans-regional power network interconnection. It is imperative for the operation of the whole power network to reinforce the network of the receiving system. In the planning of the receiving system, the determination of the voltage level for the access of a large-scale power plant to the power grid is significant to the power and voltage supports of the receiving system as well as to the operation of the inner power network in the receiving system. On the basis of the practical experiences of power system planning, this paper analyzes the advantages of the access of a large-scale power plant to the 500 kV power network, and the problems to be considered. A case study is finally presented to illustrate how to use the principles, such as simplifying the wire connection in power plant, diocrsificating the external powers sources and connecting the network by layers and zones, to determine the voltage level for the access of a large-scale power plant to the power grid.