含分布式电源的配电网保护方案设计

发布时间：2018-06-29 01:04

  本文选题：分布式电源 + 继电保护　； 参考：《南京理工大学》2014年硕士论文

【摘要】：随着分布式发电技术的快速发展以及分布式电源并网容量越来越大,其对电网带来的影响变得不可忽略。本文深入研究分布式电源大量接入后对电网继电保护的影响,其实质在于分布式电源的接入改变了原网络的结构,从而引起保护检测电流的变化,最终影响继电保护正确动作。 文章研究了分布式电源模型,主要针对典型分布式电源风机特性分析,并建立风机模型,讨论正常运行及故障情况下的电压电流波形。研究分布式电源并网控制策略,建立基于PQ控制特性的等效分布式电源模型,并通过仿真验证所采用的功率外环、电流内环的双闭环控制策略可以很好地实现定有功与定无功控制,证明所建分布式电源模型的有效性。 从理论角度系统分析了分布式电源接入位置、容量对线路保护整定的影响,在理论分析的基础之上,搭建了基于PSCAD/EMTDC暂态仿真软件平台的IEEE7节点系统来验证理论分析的正确性,并且计算了分布式电源接入点不同情况下的准入容量,结果证实理论分析与仿真计算一致,验证了理论分析的正确性和可靠性。 在综合分析多种情况下分布式电源对配电网的影响的基础之上,本文提出了基于本地信息量的自适应保护方案,通过在原始的线路电流保护基础之上添加自适应保护,可以很大程度提高线路保护灵敏度,尽可能地适应线路各种工作状态的变化,通过仿真表明算法能够很好应对分布式电源接入前后的线路过流,验证了本文提出自适应算法的有效性和正确性。 针对电流保护的不足,在分析分布式电源的接入对距离保护的影响后,提出自适应距离保护方案,主要对距离Ⅱ段的保护整定进行改进,并进行距离保护的仿真,验证了该方案的正确性和可行性。
[Abstract]:With the rapid development of distributed generation technology and the increasing capacity of distributed generation, the influence of distributed generation on power grid can not be ignored. In this paper, the influence of distributed power supply on relay protection after a large amount of access is deeply studied. Its essence lies in the fact that the access of distributed power source changes the structure of the original network, which leads to the change of protection detection current and ultimately affects the correct operation of relay protection. This paper studies the distributed power generation model, mainly analyzes the characteristics of the typical distributed power fan, and establishes the fan model to discuss the voltage and current waveform under normal operation and fault. This paper studies the grid-connected control strategy of distributed power supply, establishes an equivalent distributed power supply model based on PQ control characteristics, and verifies the power outer loop by simulation. The double closed loop control strategy of the inner loop of current can realize the constant active power and fixed reactive power control very well, which proves the validity of the model of distributed power supply. This paper systematically analyzes the influence of the location and capacity of distributed power access on line protection setting from the theoretical point of view. On the basis of theoretical analysis, an IEEE 7 bus system based on PSCAD / EMTDC transient simulation software platform is built to verify the correctness of the theoretical analysis. The access capacity of the distributed power access point is calculated under different conditions. The results show that the theoretical analysis is consistent with the simulation calculation, and the correctness and reliability of the theoretical analysis are verified. On the basis of comprehensive analysis of the influence of distributed power generation on distribution network under various conditions, this paper proposes an adaptive protection scheme based on local information, which adds adaptive protection to the original line current protection. It can improve the sensitivity of line protection to a great extent and adapt to the variety of line working state as much as possible. The simulation results show that the algorithm can deal with the over-current of line before and after the access of distributed power supply. The validity and correctness of the proposed adaptive algorithm are verified. In view of the deficiency of current protection, after analyzing the influence of the access of distributed power supply on distance protection, an adaptive distance protection scheme is proposed, which mainly improves the protection setting of the distance 鈪，

本文编号：2080142