摘要
随着城市电网的快速发展,区域负荷的不断增加,原有220kV主干网架已经无法满足大型城市的供电需求。而新建的500kV主干输电网其网架结构仍较为薄弱,无法保证供电的安全性和可靠性,因而500/220kV网架合环运行情况不断涌现。但电磁环网合环运行极大的增加了系统的短路电流,而且由于无功环流的存在降低了电网运行的经济性与安全性。针对这些问题,本文采用柔性直流输电技术通过其对功率的灵活控制特性来达到对电磁环网的潮流优化控制目的。其中,基于柔性直流系统的外部功率特性,建立了双端换流站功率注入模型;而后,把电磁环网的潮流优化控制问题转化为计及交流系统和直流系统的等式及不等式约束,并以最小有功功率损耗为目标函数的最优潮流模型求解;最后,采用遗传灾变算法对模型进行求解。算例表明,柔性直流系统能够良好的改善电磁环网系统的潮流分布,有效的降低了系统的有功功率损耗,使系统满足运行的安全性及经济性要求。
With the rapid development of the city power grid,increasing the load area,the original 220 kV main grid has been unable to meet the power needs of large cities. The new 500 kV transmission network backbone grid structure which is still relatively weak,can not guarantee the safety and reliability of the power supply,thus 500/220 kV grid network loop operating conditions are emerging. But electromagnetic Closing the Loop operation greatly increases the short circuit current of the system,but also due to the presence of reactive circulation reduces the economy and security of grid operation.To solve these problems,we use flexible HVDC technology through its flexible power control features to achieve electromagnetic loop network optimization flow control purposes. Wherein,based on the external characteristics of a flexible DC power system,the establishment of a double-ended converter station power injection model;then,the trend of the electromagnetic loop network optimization control problem into account the AC system and DC system equations and inequality constraints,and OPF to minimize active power loss as the objective function to solve;and finally,catastrophic genetic algorithm to solve the model. The example shows that the flexible DC system can be well improved electromagnetic loop network flow distribution AC system,effectively reducing the active power loss of the system,the system meet the operational safety and economic requirements.
出处
《电气开关》
2017年第2期70-73,76,共5页
Electric Switchgear
