WO2015081679A1 - 一种配电网潮流在线计算方法 - Google Patents

一种配电网潮流在线计算方法 Download PDF

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WO2015081679A1
WO2015081679A1 PCT/CN2014/079586 CN2014079586W WO2015081679A1 WO 2015081679 A1 WO2015081679 A1 WO 2015081679A1 CN 2014079586 W CN2014079586 W CN 2014079586W WO 2015081679 A1 WO2015081679 A1 WO 2015081679A1
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voltage
distribution network
distribution
power flow
sequence
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PCT/CN2014/079586
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English (en)
French (fr)
Inventor
许杏桃
李然
黄文静
高峥嵘
吕飞腾
张澄
张志宏
吴超
符瑞
邹杰
何菲
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国家电网公司
江苏省电力公司
江苏省电力公司泰州供电公司
江苏省电力公司电力科学研究院
江苏安方电力科技有限公司
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Publication of WO2015081679A1 publication Critical patent/WO2015081679A1/zh

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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H02J3/46Controlling of the sharing of output between the generators, converters, or transformers

Definitions

  • the invention relates to a technical field of economic operation analysis of a power system, in particular to an online calculation method for power flow of a distribution network.
  • Power flow calculation is an important technology to ensure the safe and economic operation of distribution network.
  • the power flow calculation of distribution network of 10kV and below is difficult to achieve online and accurate calculation.
  • the main reason is: 10kV distribution network has three-phase asymmetry problem, 10kV distribution
  • the electric transformer has both the three-phase three-wire system and the three-phase four-wire system problem and the large sampling area of the 10kV distribution network operation data; it is necessary to realize an online power flow calculation method that can solve the above problems, and to optimize the distribution network.
  • Operational recommendations provide data support.
  • the technical problem solved by the invention is to provide an online calculation method for power flow of a distribution network, which utilizes power distribution network component decoupling, node number, online calculation and node voltage sequence component calculation to recombine the power flow to solve
  • the 10kV distribution network has three-phase asymmetric, 10kV distribution transformers with the problems of three-phase three-wire system and three-phase four-wire system, and the use of distribution network power zoning calculation to solve the problem of large sampling area of 10kV distribution network operation data. .
  • the present invention provides an online calculation method for distribution network power flow, the method comprising the following steps:
  • Step 1 Decoupling the power flow calculation of the distribution network.
  • the node voltage is decomposed into positive sequence, negative sequence, and zero sequence, and then replaced with positive sequence excitation source, negative sequence excitation source, zero sequence excitation source, and excitation.
  • the source and distribution network constitute the flow distribution calculation model of the entire distribution network, and the positive sequence, negative sequence and zero sequence power flow calculation are performed respectively;
  • Step 2 classifying the distribution network nodes, the nodes are divided into outer nodes and inner nodes, and a closed loop curve is set, the outer nodes are nodes set outside the closed loop curve, and the inner nodes are nodes set in the closed loop curve;
  • the outer node is the distribution network power supply transformer busbar and the distribution transformer low-voltage side
  • the inner node is the distribution high-voltage side and each line intersection
  • the outer node is the distribution The intersection point of the network line and the closed curve and all the low-voltage sides of the distribution transformer
  • the inner node is the distribution high-voltage side and the intersection of each line;
  • the node number of the classification node is numbered from small to large, and then from small to large. Nodes are numbered;
  • Step 3 Calculate the power flow of the entire distribution network, or divide the distribution network into multiple areas for power flow calculation;
  • Step 4 The distribution intelligent terminal collects the power transformer 10kV side voltage, the distribution low voltage side voltage, the 10kV line capacitor installation point voltage, and the 10kV series transformer outlet line voltage through the wireless GPRS to calculate the power flow of the distribution network in real time;
  • the online power flow calculation in step 3 includes the following steps:
  • UBCU CA can obtain UAB + by order component decomposition Then decompose U AB + U AB- into U A + UA - .
  • the monitoring low voltage side monitoring voltage data must be multiplied by k to be converted to 10kV level.
  • Decoupling distribution network power flow calculation in the decoupled circuit, the node voltage is decomposed into positive sequence, negative sequence, zero sequence, and then replaced by excitation source, then the node is classified into the distribution network, and finally the distribution network current Online calculation, online and accurate calculation results, solved the problem of three-phase three-wire and three-phase four-wire system in the 10kV distribution network with three-phase asymmetry and 10kV distribution transformer.
  • the distribution network provides technology for solving certain types of problems across the domain.
  • FIG. 1 is an overall flow chart of a method for online calculation of power flow in a distribution network according to the present invention.
  • FIG. 2 is a schematic diagram of the entire distribution network node divided into positive sequence, negative sequence and zero sequence in the power flow online calculation system of the distribution network of the present invention.
  • Fig. 3 is a schematic diagram showing the node voltage decoupling of the power flow calculation of the distribution network in the power flow online calculation method of the distribution network of the present invention.
  • Figure 4 is a diagram showing the classification of nodes in the node number of the distribution network of the present invention.
  • a method for calculating the power flow of a distribution network includes the following steps: Step 1: Decoupling the power flow calculation of the distribution network, and decomposing the node voltage into a positive sequence in the decoupled circuit. Negative sequence, zero sequence, and then replaced by positive sequence excitation source, negative sequence excitation source, zero sequence excitation source, excitation source and distribution network constitute the entire distribution network power flow calculation model, respectively, positive sequence, negative sequence and zero sequence power flow calculation ;
  • Step 2 classifying the distribution network nodes, the nodes are divided into outer nodes and inner nodes, and a closed loop curve is set, the outer nodes are nodes set outside the closed loop curve, and the inner nodes are nodes set in the closed loop curve;
  • the outer node is the distribution network power supply transformer busbar and the distribution transformer low-voltage side
  • the inner node is the distribution high-voltage side and each line intersection
  • the outer node is the distribution The intersection point of the network line and the closed curve and all the low-voltage sides of the distribution transformer
  • the inner node is the distribution high-voltage side and the intersection of each line;
  • the node number of the classification node is numbered from small to large, and then numbered from small to large.
  • Step 3 Calculate the power flow of the entire distribution network, or divide the distribution network into multiple areas for power flow calculation;
  • Step 4 The distribution intelligent terminal collects the power transformer 10kV side voltage, the distribution low voltage side voltage, the 10kV line capacitor installation point voltage, and the 10kV series transformer outlet line voltage through the wireless GPRS to calculate the power flow of the distribution network in real time;
  • the online power flow calculation in step 3 includes the following steps:
  • U AB U Be U By order component decomposition, UAB+ UAB- can be obtained and U AB + U AB- is decomposed into U A+ UA ⁇ .
  • the monitoring low voltage side monitoring voltage data must be multiplied by k to be converted to 10kV level.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Supply And Distribution Of Alternating Current (AREA)
  • Remote Monitoring And Control Of Power-Distribution Networks (AREA)

Abstract

一种配电网潮流在线计算方法,对配电网潮流计算解耦,将节点电压分解成正序、负序、零序,再替代成正序激励源、负序激励源、零序激励源,分别进行正序、负序和零序潮流计算;对配电网节点进行分类,对分类节点进行节点编号;将整个配电网进行潮流计算;配变智能终端通过无线GPRS采集电源变压器10kV侧电压、配变低压侧电压、10kV线路电容器安装点电压、10kV串联变压器出线侧电压,对配电网潮流进行在线实时计算;采用上述计算方法,能够在线、准确的计算结果,解决了10kV配电网有三相不对称和10kV配电变压器同时存在三相三线制与三相四线制的问题,避免了面广量大的采样难题。

Description

一种配电网潮流在线计 #¾Γ¾
技术领域
本发明涉及到一种电力系统经济运行分析的技术领域,尤其涉及一种配电网 潮流在线计算方法。
背景技术
潮流计算是确保配电网安全经济运行的重要技术, 目前 10kV及以下配电网 潮流计算, 实现在线、 精确计算还很困难, 其主要原因是: 10kV配电网有三相 不对称问题、 10kV配电变压器同时存在三相三线制与三相四线制问题和 10kV配 电网运行数据采样面广量大问题;需要实现一种能够解决上述问题的在线潮流计 算方法,为提出配电网最优化运行建议提供数据支撑。
发明内容
本发明所解决的技术问题是提供一种配电网潮流在线计算方法, 利用配电 网序分量解耦、 节点编号、 在线计算和节点电压序分量计算再合成潮流来解决
10kV配电网有三相不对称、 10kV配电变压器同时存在三相三线制与三相四线制 的问题, 以及利用配电网潮流分区计算解决 10kV配电网运行数据采样面广量大 的问题。
为了解决上述技术问题,本发明提供了一种配电网潮流在线计算方法, 该方 法包括以下步骤:
步骤一:对配电网潮流计算解耦,在解耦的电路中,将节点电压分解成正序、 负序、 零序, 再替代成正序激励源、 负序激励源、 零序激励源, 激励源与配电网 构成整个配电网潮流计算模型, 分别进行正序、 负序和零序潮流计算;
步骤二: 对配电网节点进行分类, 所述节点分为外节点和内节点, 设置闭环 曲线, 所述外节点为设在闭环曲线外的节点, 内节点为设在闭环曲线内的节点; 当闭环曲线处于最大时, 外节点为配电网供电电源变压器母线和配变低压侧,内 节点为配变高压侧和各线路交叉点; 当闭环曲线小于最大闭环曲线时, 外节点为 配电网线路与闭合曲线相交点和所有配变低压侧,内节点为配变高压侧和各线路 交叉点;
对分类节点进行节点编号, 由从小到大对外节点进行编号, 再由小到大对内 节点进行编号;
步骤三: 将整个配电网进行潮流计算, 也可将配电网分成多个区域进行潮流 计算;
步骤四: 配变智能终端通过无线 GPRS采集电源变压器 10kV侧电压、配变低 压侧电压、 10kV线路电容器安装点电压、 10kV串联变压器出线侧电压, 对配电 网潮流进行在线实时计算;
步骤三中在线潮流计算包括如下步骤:
(1) 进行在线潮流计算时, 首先计算出正序和负序节点电压方程, 当总节 点数 n个, 外节点数为 i个时, 具体节点电压法导纳矩阵方程如下:
Figure imgf000004_0001
Figure imgf000004_0003
式中: Ι υ2…… ι为实测值乘以 k, IX •U„为未知量, LI2…… L 为未知量, i. ······ i„均为。值;
(2) 再计算零序节点电压方禾
Figure imgf000004_0002
Figure imgf000004_0004
(3) 实时运行参数:
①三相线电压测量值: XJA] UBCU CA 通过序分量分解, 可得 UAB+ 再将 U AB+ U AB-分解成 U A+ U A―。
②配变低压侧三相相电压测量值: ua 通过序分量分解, 可得 ua+ua-u0
③配电变压器高低压侧折算系数 k
YynO接线, 折算系数1^± :
Figure imgf000005_0001
~ Γ 。 配变低压侧监测电压数据须乘 k, 才算折算至 10kV级
2e
④不需要采集电流;
(4) 节点序分量合成实际潮流计算方程:
①配电网各节点
Figure imgf000005_0002
I 合成, 以下公式:
Figure imgf000005_0003
Figure imgf000005_0005
②配电网配变低压侧 合成, 以下公式:
Figure imgf000005_0004
采用本发明的技术方案后优点为:
将配电网潮流计算解耦, 在解耦的电路中, 将节点电压分解成正序、 负序、 零序, 再替代成激励源, 再对配电网进行节点分类, 最后对配电网潮流进行在线 计算, 能够在线、 准确的计算结果, 解决了 10kV配电网有三相不对称和 10kV 配电变压器同时存在三相三线制与三相四线制的问题。
将一条完整的 10kV线路分成几个区进行分别潮流计算, 也可根据解决问题 的需要只计算其中一个区, 避免了面广量大的采样难题, 投资少, 为整个 10kV 配电网全域范围内解决某类问题提供了技术。
附图说明
图 1为本发明配电网潮流在线计算方法的整体流程图。
图 2为本发明配电网潮流在线计算系统中整个配电网节点分为正序、负序和 零序的示意图。
图 3为本发明配电网潮流在线计算方法中配电网潮流计算解耦的节点电压 示意图。
图 4为本发明配电网节点编号中节点分类图。
具体实》式
下面结合附图对本发明作进一步详细说明。
如图 1-3所示, 一种配电网潮流在线计算方法, 该方法包括以下步骤: 步骤一:对配电网潮流计算解耦,在解耦的电路中,将节点电压分解成正序、 负序、 零序, 再替代成正序激励源、 负序激励源、 零序激励源, 激励源与配电网 构成整个配电网潮流计算模型, 分别进行正序、 负序和零序潮流计算;
步骤二: 对配电网节点进行分类, 所述节点分为外节点和内节点, 设置闭环 曲线, 所述外节点为设在闭环曲线外的节点, 内节点为设在闭环曲线内的节点; 当闭环曲线处于最大时, 外节点为配电网供电电源变压器母线和配变低压侧,内 节点为配变高压侧和各线路交叉点; 当闭环曲线小于最大闭环曲线时, 外节点为 配电网线路与闭合曲线相交点和所有配变低压侧,内节点为配变高压侧和各线路 交叉点;
对分类节点进行节点编号, 由从小到大对外节点进行编号, 再由小到大对内 节点进行编号;
步骤三: 将整个配电网进行潮流计算, 也可将配电网分成多个区域进行潮流 计算;
步骤四: 配变智能终端通过无线 GPRS采集电源变压器 10kV侧电压、配变低 压侧电压、 10kV线路电容器安装点电压、 10kV串联变压器出线侧电压, 对配电 网潮流进行在线实时计算;
步骤三中在线潮流计算包括如下步骤:
( 1 ) 进行在线潮流计算时, 首先计算正序和负序节点电压方程, 当总节点 数为 如下:
Figure imgf000007_0001
Figure imgf000007_0003
式中: ύιύ2…… ύ,为实测值乘以 k, ύ,. •U„为未知量, LI2…… I, 为未知量, i. ······ i„均为 0值;
(2) 再计算零序节点电压方程:
Figure imgf000007_0002
Figure imgf000007_0004
(3) 实时运行参数
①三相线电压测量值: UABUBeU 通过序分量分解, 可得 UAB+ UAB- 再将 U AB+ U AB-分解成 U A+ U A―。
②配变低压侧三相相电压测量值: ua U, 通过序分量分解, 可得 ua+ua-u0
③配电变压器高低压侧折算系数 k
: U le U
YynO接线, 折算系数1^± Dynll型, 折算系数正序 k + :
U 2e u 负
2e 配变低压侧监测电压数据须乘 k, 才算折算至 10kV级
Figure imgf000008_0001
④不需要采集电流;
(4) 节点序分量合成实际潮流计算方程:
①配电网各节点
Figure imgf000008_0002
I 合成, 以下公式:
Figure imgf000008_0003
Figure imgf000008_0005
②配电网配变低压侧 合成, 以下公式:
Figure imgf000008_0004

Claims

WO 2015/081679 权 利 要 求 书 PCT/CN2014/079586
1. 一种配电网潮流在线计算方法, 其特征在于, 该方法包括以下步骤:
步骤一: 对配电网潮流计算解耦, 在解耦的电路中, 将节点电压分解成正序、 负序、 零序, 再替代成正序激励源、 负序激励源、 零序激励源, 激励源与配电网构成整个配电网潮流计算 模型, 分别进行正序、 负序和零序潮流计算;
步骤二: 对配电网节点进行分类, 所述节点分为外节点和内节点, 设置闭环曲线, 所述外节 点为设在闭环曲线外的节点, 内节点为设在闭环曲线内的节点; 当闭环曲线处于最大时, 夕卜 节点为配电网供电电源变压器母线和配变低压侧, 内节点为配变高压侧和各线路交叉点; 当 闭环曲线小于最大闭环曲线时, 外节点为配电网线路与闭合曲线相交点和所有配变低压侧, 内节点为配变高压侧和各线路交叉点;
对分类节点进行节点编号, 由从小到大对外节点进行编号, 再由小到大对内节点进行编号; 步骤三: 将整个配电网进行潮流计算, 也可将配电网分成多个区域进行潮流计算; 步骤四: 配变智能终端通过无线 GPRS采集电源变压器 10kV侧电压、 配变低压侧电压、 10kV线路电容器安装点电压、 10kV串联变压器出线侧电压, 对配电网潮流进行在线实时计 算。
2. 根据权利要求 1所述的配电网潮流在线计算方法, 其特征在于: 步骤三中在线潮流计算 结果包括如下步骤:
( 1 ) 进行在线潮流计算时, 首先计算正序和负序节点电压方程, 当总节点数为 n个, 外节 点数为 i个时, 具体节点电压法导纳矩阵方程如下
Figure imgf000009_0001
(2) 再计算零序节点电压方程:
Figure imgf000010_0001
(3 ) 实时电压测量:
Figure imgf000010_0002
②配变低压侧三相相电压测量值: 11 1¾ 11
Figure imgf000010_0003
③配电变 数 k
YynO接线,
Figure imgf000010_0004
Dynl l型, 折算系数正序
Figure imgf000010_0005
配变低压侧监测电压数据须乘 k, 才算折算至 10kV级;
④不需要采集电流;
(4) 节点序分量合成实际潮流计算方程:
①配电网各节点1 1 合成, 以下公式:
Figure imgf000011_0001
3. 根据权利要求 1所述的配电网潮流在线计算方法, 其特征在于: 所述配变智能终端通过 无线 GPRS采集电源变压器 10kV侧电压、 配变低压侧电压、 10kV线路电容器安装点电 压、 10kV串联变压器出线侧电压, 再通过调度 SCADA采集供电电源变压器有载调压开关 档位。
PCT/CN2014/079586 2013-12-05 2014-06-10 一种配电网潮流在线计算方法 WO2015081679A1 (zh)

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