Single Line Diagram Research Articles

Auto-drawing Regional Discrete Reconfiguration Algorithm for Distribution Intelligent Network

Reconstruction of a distribution network is a complex nonlinear combinatorial optimization problem. This paper presents a technique for the auto-drawing regional discrete reconfiguration algorithm (ARDRA) of distribution intelligent network systems, which is very important for the control, monitor, identification and separation in distribution systems. The integer coding strategy based on the independent regional discrete loop was adopted, and the initial data of distribution network was input, followed by random generation of the effective initial swarm of corresponding scale. The ternary tree, alignment algorithm and power flow calculation was adopted for the ARDRA calculation of effective solutions. The server draws the single line diagram automatically and sends it back to the client, which can be verified by the client. The simulation results based on the IEEE33 node distribution system showed that the active network loss value of the system was decreased obviously, reaching 16.57%. The active power P increased significantly compared with that before the reconfiguration in which the distributed generators were accessed. The proposed algorithm has good optimization performance in solving the problem of distribution network reconfiguration compared with the traditional particle swarm optimization (PSO) and the differential evolution (DE) algorithm.

Investigation on Voltage Quality Problems on the Process of Cement Industry Production in Indonesia: A Case Study of Cement Kupang Factory - Indonesia

The decline in the quality of electric power becomes a serious problem in the industrial sector and affects a significant cost loss. One of the dominant power quality problems is the voltage dip. The use of electric motors in an industry becomes one of the main causes. This paper discusses the investigation on voltage dip problems at a cement factory at Kupang,, Indonesia. The cement factory uses an induction motor as the prime mover and is proven to trigger a voltage dip because of its high starting current. Based on the observed data of the disturbance, a single line diagram was created. The single line diagram was analyzed using an equivalent circuit. It was found out that as the induction motor was started, it created a very significant voltage drop as of 20.43 % to 62.26 %. The voltage dip correlated to the capacity of the induction motor used. The larger the capacity of the induction motor, the larger the voltage dip occured.

Алгоритм автоматизированного выбора схем электрических соединений открытых распредели-тельных устройств напряжением 35–750 кВ в САПР «ОРУ CAD»

Using CAD when designing the electrical part of substations does reduce the time spent by the designer to solve routine problems. The paper describes an algorithm for computer-aided selection of single-line diagrams for 35- to 220-kV outdoor switchgears as implemented ORU CAD. The algorithm herein proposed selects switchgear SLD based on the effective codes and design standards. In addition, alternative options are proposed that satisfy some of the conditions for their subsequent comparison by the reliability criteria and the resultant costs. When running SLD selection, the algorithm considers such factors as the voltage class and number of connections, the type of substation, the number of non-redundant connections, and the need for an ice-melting system on power lines. In addition, for dead-end substations it considers the possibility of transmitting a relay protection signal to the power supply switch as well as the presence of dead-end substations on the power transmission line. For pass-through substations, it considers the possible need for frequent power transformer switching. The software described in this paper can be used as an automated workstation for the electrical engineer responsible the electrical part of the substations.

Analysis of Electrical Power Consumption in Container Crane of Container Terminal Surabaya

Container crane electrification is a re-powering process of container cranes from diesel to electricity. In electrification process, it is required an analysis of electrical power consumption that is needed in the operational of container crane. It aims to determine whether the amount of electrical power that is supplied by PLN can be optimally used in the operational of container crane to do loading and unloading activities. To perform the analysis of electrical power consumption, it is required various data and calculations. The required data are container crane specifications and other electrical equipment specifications, the amount of electrical power that is supplied by PLN, also the single line diagram from the electrical system at the port. While, the calculations that is needed to be performed are the calculation of electrical power load in motors and other electrical equipments, the calculation of nominal current and start current, the selection of cable and busbar, and the calculation of wiring diagram junction power. From the calculations that has been done, then the next step is to do the load flow analysis simulation by using software simulation, so an accurate and effective load flow analysis can be obtained to optimize loading and unloading activities at the port. The result of this research, it can be seen that container crane electrification will give advantages in both technical and economical for the company and for the ship, such as accelerate the loading and unloading time of containers and reduce idle time, especially in the operational of diesel generator .

A standards-based approach for Auto-drawing single line diagram of multivendor smart distribution systems

This paper presents a technique for the auto-drawing of single line diagram (SLD) of multivendor distribution systems. SLDs are used in electric power system visualization, which is very important for the control and monitoring of distribution systems for fault location, identification, separation, and service restoration. The task of auto-drawing an SLD for distribution systems has been made complicated due to the introduction of distributed generations and multivendor distribution systems. This paper proposes an algorithm for auto-drawing SLD, based on a ternary tree and collision avoidance algorithm. In addition, a standards-based approach is suggested for incorporating different distribution system planned and run by different vendors. Initially, client converts the distribution system diagram to a standard model, which is then sent to the server. The server draws the SLD by using the auto-SLD drawing algorithm and sends it back to the client, which can be verified by the client.

Visualizing the Electrical Structure of Power Systems

Recent work, using electrical distance metrics and concepts from graph theory, has revealed important results about the electrical connectivity of empiric power systems. Such structural features are not widely understood or portrayed. Power systems are often depicted using unenlightening single-line diagrams, and the results of loadflow calculations are often presented without insightful elucidation, lacking the necessary context for usable intuitions to be formed. For system operators, educators, and researchers alike, a more intuitive and accessible understanding of a power system's inner electrical structure is called for. Data visualization techniques offer several paths toward realizing such an ideal. This paper proposes various ways, in which electrical distance might be defined for empiric power systems, and records how well each candidate distance measure may be embedded in two dimensions. The resulting 2-D projections form the basis for new visualizations of empiric power systems and offer novel and useful insights into their electrical connectivity and structure.

Installation and Commissioning of a 100 kW Rooftop Solar PV Power Plant

Objectives: The grid connected rooftop solar photovoltaic system is gaining momentum. The feasibility study of its installation, testing, commissioning and grid connectivity issues is a must. The analysis of economic benefits in comparison with electricity charges as per utility and the payback period is prime requirement. The objective is to integrate solar power with grid and share a greater portion of solar power for the local use and contribute the solar power installed capacity of the nation Methods/Statistical Analysis: The paper gives a comprehensive study of site information, plant architecture, layout, single line diagram and test results prior to commissioning. An operation and maintenance sheet has been maintained to track the various parameters such as voltage, current and power both on DC and AC mains for individual inverters. The average V DC , I DC and P DC has been found to be 620 volts, 32 Amps, 20 kW respectively from 11 am to 4 pm on bright sunny days. Similarly, V DC , I DC and P DC were noted to be 440 volts, 27 Amps, 20 kW respectively.Findings: During light loading in the institute, the power flow from solar to grid was evidenced through net meters installed by the utility. This relieved the institute management to pay heavy electricity charges. The electricity charge by the utility for HT consumer was Rs.10 per kWh whereas the solar charges were paid at the rate of Rs. 6.4. This resulted in a significant cost saving. Application/Improvements: The power taken from grid during 11 am to 4 pm has been reduced from an average 45 kWh to 12 kWh per hour. The scheme is well suited for large commercial complex, residential buildings and offices. It can be implemented with battery back up in remote villages which has poor access to electricity.

Visualization of distribution system planning for engineers and decision-makers

Planning of an electric distribution network is a complex task, requiring a comprehensive approach that includes collecting and analyzing large amounts of technical and nontechnical data. In addition, the outcome of the planning procedure needs to be supported by economic analysis that provides pathways for future investments. In order to present the planning results to various groups of people, such as technical staff, managers, and politicians, different visualization techniques are used. Data visualization, as a branch of descriptive statistics, is important to understand and present information in an effective manner. The basic idea of visualization is to present data in a visual form, allowing a person to get a quick insight into the data, draw conclusions, and directly interact with the data. Some traditional methods, such as graphs, histograms, 2D column and line charts, single line diagrams, and 3D surfaces with contours, are mandatory for visualizing power data. However, in the electric power system business there is a growing need for geographically referenced visualization. While there is a lot of research being done on visualizing data in transmission power systems, the number of studies on display methods in distribution power systems is limited. The focus of this paper is the visualization of data used during the distribution network planning process.

PROVIDING QUALITY OF ELECTRIC POWER IN ELECTRIC POWER SYSTEM IN PARALLEL OPERATION WITH WIND TURBINE

The problem of providing electric power quality in the electric power systems (EPS) that are equipped with sufficiently long air or cable transmission lines is under consideration. This problem proved to be of particular relevance to the EPS in which a source of electrical energy is the generator of wind turbines since the wind itself is an instable primary energy source. Determination of the degree of automation of voltage regulation in the EPS is reduced to the choice of methods and means of regulation of power quality parameters. The concept of a voltage loss and the causes of the latter are explained by the simplest power system that is presented by a single-line diagram. It is suggested to regulate voltage by means of changing parameters of the network with the use of the method of reducing loss of line voltage by reducing its reactance. The latter is achieved by longitudinal capacitive compensation of the inductive reactance of the line. The effect is illustrated by vector diagrams of currents and voltages in the equivalent circuits of transmission lines with and without the use of longitudinal capacitive compensation. The analysis of adduced formulas demonstrated that the use of this method of regulation is useful only in the systems of power supply with a relatively low power factor (cosφ < 0.7 to 0.9). This power factor is typical for the situation of inclusion the wind turbine with asynchronous generator in the network since the speed of wind is instable. The voltage regulation fulfilled with the aid of the proposed method will make it possible to provide the required quality of the consumers’ busbars voltage in this situation. In is turn, it will make possible to create the necessary conditions for the economical transmission of electric power with the lowest outlay of reactive power and the lowest outlay of active power losses.

디지털변전소 엔지니어링 툴 구현을 위한 IEC 61850 국제규격 기반의 변전소 토폴로지 표현에 관한 연구

In order to complete engineering works of the digital substation, Both Data transmission among a variety of IEDs and HMIs, and single line diagram of the substation might be done based on XML documents published in IEC 61850 international standards. This kind of XML based engineering process for the digital substation must be implemented not by manual written work but by the engineering tool using a computer. But most of the engineering tools do not support system based engineering works such as single line diagram of the substation but have only function to set IEDs as single device unit. Accordingly, this paper presents a new design method of the system based engineering description applicable to real IEC 61850 based substation through analyzing the current international standard and its sampled engineering file, and shows implementation of the engineering tool of the digital substation with the result of this study.

Planning of network system for the distribution and transmission areas of electric energy

In this project, we developed a computational system based on a framework of geo-referenced data that uses Google Maps technology. The focus is on improving the modeling of information for viewing and embedding technology, human-computer interface (HCI) which includes visualization environments synchronized. The first environment allows you to have the vision of the network elements in the form of electrical single line diagram, representing a consolidated technique in the field of electricity. The second environment called GIS is a map-based navigation with Google Maps that allows the physical location of where it is represented the elements present in the electrical line diagram. This integrated system is capable of supporting the planning of network expansion works in the areas of distribution and transmission of electricity.

제철소 후판공장 전원공급설비의 용량 최적화에 관한 연구

In this paper, we suggest an optimization method which can save about 5[%] of the cost though the optimizing of configuration and capacity for the facility. To achieve this goal, we compared the design data of the power, motor and drive system with the actual operation data of the plate mill plant in K-Steelworks. Therefore we measured the actual loading data by facilities considering the operating conditions of the plate mill plant in K-Steelworks, after that analyzed these data. In addition, we review the optimal capacity for transformer, switchgear and drive, and also reconfigured the electrical room and power single line diagram through the validation of motor data by equipment and the confirmation of process data considering the load characteristics. Consequently, the optimization method of capacity for the facilities shall have effectiveness in building new plate mill plant to further reduce costs at future.

Power Quality Improvement by IUPQC with Fuzzy Control Technique

This paper proposes a new connection for a unified power quality conditioner (UPQC) to improve the power quality of two feeders in a distribution system. A UPQC consists of a series voltage-source converter (VSC) and a shunt VSC both joined together by a common dc bus. It is demonstrated how this device is connected between two independent feeders to regulate the bus voltage of one of the feeders while regulating the voltage across a sensitive load in the other feeder. Since the UPQC is connected between two different feeders (lines), this connection of the UPQC will be called an interline UPQC (IUPQC). The structure, control and capability of the IUPQC with PI and FUZZY controller technique are discussed in this paper. The efficiency of the proposed configuration has been verified through simulation studies using MATLAB. Index Terms: distribution static compensator (DSTATCOM), distribution system, dynamic voltage restorer (DVR), fuzzy logic controller, power quality (PQ), Interline unified power quality conditioner (IUPQC) . I. Introduction Voltage Source Converter (VSC) based custom power devices are increasingly being used in custom power applications for improving the power quality (PQ) of power distribution systems. Devices such as distribution static compensator (DSTATCOM) and dynamic voltage restorer (DVR) are the facts devices. A DSTATCOM can compensate for distortion and unbalance in a load such that a balanced sinusoidal current flows through the feeder. It can also regulate the voltage of a distribution bus. A DVR can compensate for voltage sag/swell and distortion in the supply side voltage such that the voltage across a sensitive/critical load terminal is perfectly regulated .A unified power quality conditioner (UPQC) can perform the functions of both DSTATCOM and DVR. The UPQC consists of two voltage-source converters (VSCs) that are connected to a common dc bus. One of the VSCs is connected in series with a distribution feeder, while the other one is connected in shunt with the same feeder. The dc links of both VSCs are supplied through a common dc capacitor. It is also possible to connect two VSCs to two different feeders in a distribution system. In, a configuration called IDVR has been discussed in which two DVRs are connected in series with two separate adjacent feeders. The dc buses of the DVRs are connected together. The IDVR absorbs real power from one feeder and maintains the dc link voltage to mitigate 40% (about 0.6p.u.) voltage sag in the other feeder with balanced loads connected in the distribution system. It is also possible to connect two shunt VSCs to different feeders through a common dc link. This can also perform the functions of the two DVRs mentioned above, albeit with higher device rating. This paper presents a new connection for a UPQC called interline UPQC (IUPQC). The single-line diagram of an IUPQC connected distribution system is shown in Fig. 1.

Mitigating Arc-Flash Hazards: A Case Study of a Mill-Wide Project

This article provides a comprehensive account of a mill-wide project to bring a more than 30-year-old market pulp mill into compliance with NFPA 70E requirements and to mitigate arc-flash hazards to reasonable enough levels to allow effective maintenance. The project spanned three years and was completed in 2011. The major activities to be discussed (and through which the project had to progress) include the decision to initiate, data collection or re-creation, and update of single-line diagrams; creation of a database and software model, short-circuit analysis, multiple upgrades, or replacements to address over-dutied equipment; arc-flash analysis, protection/coordination changes to address let-through energy, equipment upgrades or replacements to address let-through energy and mitigate arc-flash hazards; equipment labeling; and training of personnel.

서비스 지향적 방법론 기반의 배전선로 회선별단선도 생성 기법

A single line diagram is a graphic user interface to represent electrical connectivity between power equipments in distribution automation systems. This paper proposes a new single line auto-drawing technique based on the service oriented architecture. Web service, CIM(Common Information Model) and SVG(Scalable Vector Graphics) are adopted to implement SOA concept. A web service demo system was established which is configured with the service provider, consumer and broker to verify the feasibility of this study.

Spatiotemporal Load-Analysis Model for Electric Power Distribution Facilities Using Consumer Meter-Reading Data

The load analysis for the distribution system and facilities has relied on measurement equipment. Moreover, load monitoring incurs huge costs in terms of installation and maintenance. This paper presents a new model to analyze wherein facilities load under a feeder every 15 min using meter-reading data that can be obtained from a power consumer every 15 min or a month even without setting up any measuring equipment. After the data warehouse is constructed by interfacing the legacy system required for the load calculation, the relationship between the distribution system and the power consumer is established. Once the load pattern is forecasted by applying a clustering and classification algorithm of temporal data-mining techniques for the power customer who is not involved in automatic meter reading, a single-line diagram per feeder is created, and power-flow calculation is executed. The calculation result is analyzed by using various temporal and spatial analysis methods, such as the Internet geographic information system, single-line diagram, and online analytical processing.

An Auto-drawing Algorithm for the Single Line Diagram of Distribution Systems

Distribution Automation System(DAS) is designed to improve operational efficiency by acquisition and control of remote data using its components such as central computation units, communication network and feeder remote terminal units. A conventional human machine interface of the DAS adopts a schematic diagram which is made by drawing power equipments on the geographic information system map. The single line diagram is more useful than the schematic diagram for the main tasks of distribution system operation such as protective relay coordination, service restoration and loss minimization. Since the configuration of the distribution line is changed according to the relocation of the open tie switches, the auto-drawing algorithm based on the connection between the sections and the switches is an essential technique. This paper proposes a new auto-drawing algorithm for a single line diagram of distribution systems based on tertiary tree and collision avoidance method. The feasibility of the proposed algorithm has been testified for various cases using practical distribution system with 12 feeders.

Development of an Intelligent Station HMI in IEC 61850 Based Substation

Because the existing Human-Machine Interface (HMI) for the conventional substation cannot dynamically indicate the configuration information of the Substation Automation System (SAS). In this paper, an intelligent station HMI is proposed for IEC 61850 based substation. The program of the proposed HMI not only can automatically generate the layout of single line diagram, but can also indicate the communication network and functions of IEDs by reading SCL files. It greatly helps monitor the operation status, communication network and each IED dynamically, such as failure detection in SAS. Furthermore, this paper presents the possibility of developing new software for SAS with the full use of IEC 61850-6. Once the software is complete, there is no need to change it when the substation is upgraded or when it is migrated to other IEC 61850 based substations, which is a cost-effective solution.

직접연계방법에 의한 DAS-SCADA 연계 연구

배전자동화시스템(DAS:Distribution Automation System)과 변전자동화시스템(SCADA:Supervisory Control And Data Acquisition)은 전력계통을 컴퓨터와 통신기술을 이용하여 운용하는 주된 시스템으로, 현재 독립적으로 운영됨으로 인해 신속하게 처리되어야 하는 고장처리 및 활선작업처리가 지연되는 등의 문제점이 제기되어왔고, 이에 따라 DAS-SCADA 연계 연구가 요구되었다. 연계방법으로 직접연계, 웹연계, DAS 기능부 전력량계를 이용한 연계가 2005년 11월부터 2007년 12월까지 한전 사업소에서 시범 운영되었고, 그 결과 투자비용 면에서 직접연계방법이 웹연계 방법에 비해 약 1.3배 높지만 다양한 변전소 운전정보 전달의 신속성, 제어기능 우수 등의 타당성이 입증됨으로써 직접연계방법에 의한 DAS-SCADA 연계가 2010년까지 한전 사업소에 전국적으로 확대 적용될 계획이다. 시범 운영시 제기된 문제점을 개선하기 위해 변전소 개체별 통신 방법을 이용한 데이터 연계방안으로 개선하여 연계DB 자동구축 기능 및 연계시스템 진단/Log 기능을 개발하였다. 연계데이터 포인트와 통신데이터 종류를 정의하고, SCADA HMI 프로그램을 개발하여 변전소 단선도 자동생성 기능, 변전소 단선도 수동편집 기능, SCADA 감시 제어기능 및 이력관리 기능을 개발하였다. DAS-SCADA 연계시 정전건당 평균시간을 약 33% 단축하여 전력공급 신뢰도를 향상하고, 배전 계통운영센터와 변전소간 활선작업 처리절차 축소로 전력계통 효율적 운영에 기여하고, 나아가 고장시 부하절체 자동처리로 완전한 배전자동화 실현 및 해외 수출화 사업에도 크게 기여할 것으로 기대된다. DAS and SCADA system are main systems, which operate and manage the power system by using computer and communication technology. But DAS and SCADA have been operated independently in Korea, so there was some time delay in the fault handling and live-line work. To improve that problems, studies on the interface between DAS and SCADA have been needed. From November 2005 to December 2007, the pilot project has been performed in KEPCO's branch offices, as a result, direct method will be applied widely all over the country until 2010 because the operation information of substation users want can be transmitted fast and it is possible to control 43RC directly although the expense for direct method is about 1.3 times larger than that for web method. To improve problems revealed during the pilot project, substation object to object communication method is proposed and interface database automatic generation and interface system diagnosis and logging functions are developed. Interface data point and communication data type are defined, substation single line diagram automatic generation or manual editing function, SCADA monitoring and controlling function, log data managing function are developed in SCADA HMI program. It is expecting to reduce the average time for each outage about 33% and to improve the reliability, efficiency of operation, execution of DAS from automatic load transfer under a fault, and to contribute to export project.

공항 수.배전설비 제어시스템 표준화

국내공항의 경우 전기설비의 중요도에 비해 이에 대한 설계기준이나 표준지침이 제대로 갖추어지지 않아 오늘날 공항의 건설, 공항시설의 확충, 증설시에 체계적이고 표준화된 수ㆍ배전설비를 갖추기 어려운 실정이다. 따라서, 본 논문에서는 국내공항을 Code화에 의한 4등급으로 분류하고 수ㆍ배전설비에 대한 정의 및 적용범위를 설정한 후 기존공항의 수ㆍ배전설비에 대한 문제점을 분석하고 공항 수ㆍ배전설비 제어시스템 기준과 공항 등급별 3단계 방안을 제시하여 공항등급별 표준 단선 결선도를 작성한 다음 단선 결선도에 따른 공항 수ㆍ배전설비 시설기준을 제시한다.