含分布式电源的三相不平衡配电网潮流计算_赵晶晶

第33卷第3期电网技术V ol. 33 No. 3 2009年2月Power System Technology Feb. 2009

文章编号：1000-3673（2009）03-0094-05 中图分类号：TM744；TM91 文献标志码：A 学科代码：470·4051含分布式电源的三相不平衡配电网潮流计算

赵晶晶，李新，许中

（输配电装备及系统安全与新技术国家重点实验室(重庆大学)，重庆市沙坪坝区 400044）

Calculation of Three-Phase Unbalanced Power Flow in Distribution Network

Containing Distributed Generation

ZHAO Jing-jing，LI Xin，XU Zhong

（State Key Laboratory of Power Transmission Equipment & System Security and New Technology

(Chongqing University)，Shapingba District，Chongqing 400044，China）

ABSTRACT: According to actual conditions of three-phase unbalance in distribution network, to accurately calculate the power flow of distribution network connected with various distributed generations (DG) a three-phase unbalanced power flow algorithm based on forward and backward substitutions, that can cope with DG modeled as PV or PQ nodes, is proposed. In accordance with topological structure of distribution network and by use of laterals delaminating technology the calculation of power flow is speeded up. During the coping with DG modeled as a PV node, taking the amplitude of positive sequence voltage as voltage regulating parameter the amplitude difference between positive sequence voltage and rated voltage is calculated, then the amount of reactive power compensation for PV node is obtained and then the DG represented by PV node operation model is changed into that represented by PQ node operation model. The correctness of the proposed algorithm is verified by the calculation results of IEEE 34-bus test system. Finally, by means of analyzing the ability of voltage regulation and reactive power compensation of DG, the impacts of various types of DGs on distribution network voltage are researched.

KEY WORDS: distributed generation (DG)；distribution network；three-phase unbalanced power flow；power system

摘要：根据配电网三相不平衡的实际情况，为准确计算各种分布式电源(distributed generation，DG)并入配电网后的潮流问题，文章基于前推回代法，提出了可处理PV和PQ节点模型DG的三相不平衡潮流算法。按照配电网拓扑结构，利用支路分层技术，加快了潮流计算速度。在处理PV节点模型DG时，将电压正序分量幅值作为电压调节参数，计算电压正序分量幅值和额定电压幅值差，得到PV节点的无功补偿量，将DG由PV节点运行模型转换为PQ节点运行模型。IEEE 34节点系统算例结果验证了该算法的正确性。最后，通过分析DG对电压的调节和无功补偿能力，研究了不同类型DG对配电网电压的影响。

关键词：分布式电源；配电网；三相不平衡潮流；电力系统0 引言

近年来，风能、太阳能、燃料电池、热电联产等形式的分布式电源(distributed generation，DG)作为综合利用现有资源的理想方式[1-8]，日益受到电能部门和研究人员的关注。DG通过在负荷端附近建立小规模电源，采用与大电网相结合的供电模式，可缓解传统发电模式产生的电能质量、可靠性、环境保护等诸多问题。随着DG并入配电网数量逐渐增多，配电网由单电源模式变为多电源模式。传统的配电网潮流算法因未考虑各种形式的DG并网而不再满足要求，研究涉及DG影响的潮流算法尤为重要。

通常，配电网存在三相支路参数不对称和三相负荷不平衡结构特性。配电网中的负荷可按三相和单相方式连接，三相连接可分为星形和三角形方式，单相连接可分为线到地和线间方式等，所以配电网的潮流计算应考虑三相不平衡情况。根据DG接入配电网的方式，DG在潮流计算中可作为PQ或PV节点处理。目前三相不平衡配电网潮流计算中都未考虑处理PV节点类型DG的方法，DG 并网后对配电网电压、网损等影响的分析也建立在潮流计算的基础上[9-10]，因此，提出一种可处理多个PQ和PV节点类型DG同时接入配电网的三相不平衡潮流计算方法十分必要。目前关于含DG的配电网潮流计算的研究并不多[11-15]：文献[13]介绍了DG与电网互联的3种常见接口类型，提出了基于