面向不对称察觉的低压配电网分相接线图自动成图

态势可视化是低压配电网现代化监管关键技术之一,为此提出配电变压器为中心低压配电网(TCDN)概念作为研究及工程应用的对象和目标。清晰美观的接线图自动生成是TCDN态势可视化的前提,接线不对称性和负荷不对称性是低压配电网的关键特点,因此提出2类适合态势感知的分相接线图布局设计。提出了TCDN分相接线图自动生成原理,基于该原理的接线图,既能确保三相四线主干线和三相用户的接线对称性,也能清晰识别出单相双线用户导致的接线不对称性。对于提出的虚拟全单相接线图形,基于其单线束扇形图形设计参数和排列顺序,提出了单线束初始布局以及缩放和旋转参数计算方法以生成初始图形,再进行基于力导的美化计算以得到较为美观的图形。基于提出的原理,得到的虚拟全单相接线图形可以分解组装得到分相接线图。案例验证了该方法的快速性和有效性,其电压态势时序图片可以很好地察觉含单相户用光伏、单相及三相负荷变化下的低压配电网动态运行特性。

Auto-generation of Phase-separated Connection Diagram for Asymmetry Perceptible Low-voltage Distribution Network

Situation visualization is a core technology for monitoring and management of low-voltage distribution network (LVDN). Therefore, a new concept of transformer centralized low-voltage distribution network (TCDN) is suggested as an object and target to guide corresponding research and engineering application. Auto-generation of a clear and beautiful phase-separated connection diagram becomes a pre-condition for situation visualization. For wiring asymmetry and load asymmetry being core characteristics of LVDN, two types of situation-oriented connection diagrams are designed. An auto-generation principle is proposed for phase-separated connection diagram of TCDN, so that not only the connection symmetry of three-phase four-wire main branches and the connected three-phase customers is guaranteed, but also the connection asymmetry caused by single-phase two-wire customers can be clearly perceived. For the proposed whole phase virtual connection diagram, based on the provided parameters of fan-shape layout and the arrangement order of each wiring harness, the initial layout and routing methods for each wiring harness by in-out zooming and rotating algorithm are proposed to yield an initial diagram, followed by further force-direction based beautifying algorithm to generate a nice connection diagram. The generated whole phase virtual connection diagram will be finally disassembled into the phase-separated connection diagrams according to the proposed auto-generation principle. The case study verifies the efficiency and effectivity of the proposed algorithm. Moreover, the time sequence pictures of voltage profile based on the generated phase-separated connection diagram show a very good perceptible understanding of dynamic operation characteristics of TCDN caused by variations of power outputs from single-phase household photovoltaics and power assumptions from single-phase and three-phase load.