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Contents Sponsor I Cosponsors Profile Technical Sessions I - Substation Automation and Integration 1. IEC 61850: Role of Conformance Testing in Successful Integration Eric A. Udren, Willem Strabbing, Dave Dolezilek KEMA Consulting - USA KEMA Consulting Netherlands Schweitzer Engineering Laboratories - USA 2. Requirements of Interoperability and Communication Redundancy In IEC 61850 based SA Systems Rajiv Krishnan, ABB Limited, Bangalore 3. IEC 61850 Standards in Substation Automation G Krishnamurthy Kerur, Easun Reyrolle Ltd, Bangalore 4. Modular Concept For Protection & Substation Automation Based Ehv Substations Kuldeep Tickoo, Bhupendra Badiya, Siemens - India

For lee 61850

5. Advanced Substation Automation: An Overview Dr. R. P. Gupta, Distribution Automation Research Centre, CG Global R & D Centre, Crompton Greaves Ltd., Mumbai - 400 042, India 6. Planning for the Successful Integration of Substation Communications J.M Shaw, Garret/Com, Inc. 7. IEC 61850 Substation LAN - Issues to Consider when Designing and Deploying Ethernet Networks Roger Moore, and Rene Midence, RuggedCom

II - Control Centre 8. Control Center Design Today Dr. Michael Wolf, PSI CNI GmbH, Germany 9. Human-Machine Interface for Large-Scale Systems Dr. Michael Wolf

Distribution

Management

lOUse of Large Screen Displays in Automated Industries Broader process views for improved abnormal situation management. Barco III - Economics of Automation 11 Cost Justification of SCADA/DMS Due to Loss Reduction Albana 110, Roland Eichler and Vikram Gandotra, Siemens India 12 The Cost of Network Control Dr. Michael Wolf, with PSI CNI GmbH, Germany 13 Innovative Optical Sensor Technology - The Foundation of Cost Effective MV ILV Distribution Network Monitoring James Northcote-Green, Martin Speiermann and Alfred Manohar Consultant, ABB and PowerSens, UK, PowerSense AlS , Amtech Automation , Bangalore, India

47 Implementation of SCADAIEMS System for Distribution System Automation P. V.Chopade, D. G.Bharadwaj, Bharati Vidyappeth University College of Engineering, Pune, INDIA 48 NDPL Substation Automation Project: Step forward for Automation integration Sanjay kumar Banga and Ajay Prashant Biswas, NDPL, New Delhi 49 Omniagate

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Paper for National Conference on Distribution Automation @CPRI Bangalore

Implementation of SCADA/EMS System for Distribution System Automation P.V.Chopade Member IEEE,

D.G.Bharadwaj

Distribution Automation System (DAS) as a system that enables an electric utility to remotely monitor, coordinate and operate distribution components, in a real-time mode from remote locations. The distribution automation system is based on an integrated technology, which involves collecting data and analyzing information to make control decisions, implementing the appropriate control decisions in the field, and also verifying that the desired result is achieved. The location, from where control DA system is beneficial in day-to-day operation and maintenance of distribution network. The other benefits of the distribution automation are: reduced technical and commercial losses, improved cash flow, lower electric service restoration time, reduction in equipment damage, better availability of system information, improved operational planning, remote load control and shedding, and enhanced power quality and reliability

AbstractAutomation of power distribution systems has increasingly been adopted by power utilities worldwide in recent years. This is to provide a more reliable supply to its customers and to enhance operational efficiency. This can be used for the distribution network of about llKV to 25 KV. SCADA system can be used as an important building block for automation of distribution network. The SCADA system was commissioned and became operational in mid 1988. Due to continuous network expansion & increasingly higher expectations of consumer demands for electrical energy are continuously increasing. So the distribution system needs continuous upgrading to incorporate more remote terminal units (RTUs) as well improved functional enhancements. In this paper implementation of SCADA system in distribution automation & the benefits through incorporating such system are presented; along with a case study for PECO energy company.

I!. NEED OF DISTRIBUTION SYSTEM AUTOMATION [I ][2] Index Terms (Keywords) - seA DA/EMS, Distribution System, Automation.

I.

INTRODUCTION

Electric power is normally generated at 11-25kV in a power station. To transmit over long distances, it is then stepped-up to 400kV. 220kV or 132kV as necessary. Power is carried through a transmission network of high voltage lines. Usually, these lines run into hundreds of kilometers and deliver the power into a common power pool called the grid. The grid is connected to load centers (cities) through a subtransmission network of normally 33kV (or sometimes 66kV) lines. These lines terminate into a 33kV (or 66kV) substation, where the voltage is stepped-down to IlkV for power distribution to load points through a distribution network of lines at IlkV and lower.

P.V.Chopade is with the Bharati Vidyappeth University Engineering ,Pune-43, M.S.,INDIA, Member IEEE. +91020-24370991: fax +91 020e-mail: plavinchoml.!~ccl.:.org).

College of ( phone: 24372998' ~

D.G.Bharadwaj is Professor of Electrical Engineering Department and Head of Research and Development Cell, Bharati Vidyappeth University College of Engineering ,Pune-43, M.S.,INDIA. (e-rnail: dattatra\.Mveth.net).

To minimize Distribution Losses: The demand for electrical energy is ever increasing. Today over 21 % (theft apart!!) of the total electrical energy generated in India is lost in transmission (4-6%) and distribution (15-18%). The electrical power deficit in the country is currently about 18%. Clearly, reduction in distribution losses can reduce this deficit significantly. It is possible to bring down the distribution losses to a 6-8 % level in India with the help of newer technological options (including new technology) in the electrical power distribution sector which will enable better monitoring and control. To minimize voltage sags & interrupts: In general, medium voltage (MV) power distribution networks are operated radially, with different levels distribution automation. Investment in distribution automation is a technical and an economic optimizations issue to considered in distribution network design. The purpose is minimize long term total costs including costs of investments, losses, outages and poor power quality within relevant constraints. Power quality is of increased concern. Previously, long interruptions have been of major interest but nowadays focus is on shorter interruptions. From the customer point view, short interruptions and voltage sags affect customer equipment in the same way. Distribution automation caused to control the influence of interruptions and voltage sags.

Paper for National Conference on Distribution Automation @CPRI Bangalore Novel solutions of distribution automation include, example, modern, intelligent systems and equipment for fault isolation and optimized operation and control of the network. From the customers' point of view interruptions and voltage sags have an equally harmful influence on the operation of equipment and processes. An interruption is defined as the complete loss of voltage « 0.1 p.u) and a voltage sag as a voltage drop to between 0.1 and 0.9 p.u. in rms voltage [I). Voltage sags can be characterized by magnitude, duration, and number [2]. The lower the sag magnitude and/or the longer the sag duration, the higher is the probability of disoperation of the customer's equipment. In radially operated MV networks having circuit breakers only at the substation, a customer experiences sags caused by faults in the neighboring MV feeders, while customers supplied by the faulted feeder will face an interruption. In a construction with downstream circuit breakers along the feeders, customers will also experience sags caused by faults in the neighboring feeders. In this situation, depending on the relative location of the customer and the fault, customers may also experience interruptions and sags caused by faults occurring in the same feeder as the customers themselves. Thus distribution automation is essential to improve the overall efficiency of distribution system by remotely monitoring the distribution system & facilitating supervisory control of devices and provides decision support tools to improve the system performance.

111. SCADA {EMS SYSTEM

Figure I : SCADA Communication

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SCADA system: The term refers to a large ..scale, distributed measurement (and control) system. SCADA systems are used to monitor or to control chemical or transport processes, in municipal water supply systems, to control electric power generation, transmission and distribution, gas and oil pipelines, and other distributed processes. Basically it includes I. Data Acquisition (collection) equipment 2. Data transmission telemetric equipment 3. Data monitoring equipment 4. HMI (Human machine interface) 5. Networks ,communication database & software's etc.

Figure 2: Remote Control Station in SCADA system

SCADA equipments are located in master control centre , zonal regional control centers, district control centers , control rooms of generating stations & large sub-stations. SCADA requires two way communication channels between master control centers & remote control centers as shown in the following diagrams i.e. in figure I & figure 2.

The possibility and inevitability to perform this integration process will drive all utilities toward the standardization of data models and communication ·protocols. Existing communication tools must be modified or replaced to accommodate extensive information exchange. Internet based communication network enables information sharing and various network applications and provide an ideal infrastructure for the next generation of power communication network. Various Internet/Intranet applications are replacing, upgrading, and extending the existing power communication establishment. Open access same-time information system (OASIS) is a good example.

Traditional power communication system is established mainly for intra-company information exchange. Low bandwidth and communication isolation hinders large infonnation exchange and inter-operation. Deregulation results in horizontal merger and consolidation of many existing utilities. Inter-company communication and integration of data from various control centers, power plants. and substations. is required.

Functions of SCAD A in Electrical power distribution system: Certain functions are basic to electric utility SCADA systems. The more common functions include:. I Data Acquisition 2 Information Display 3 Supervisory Control 4 Alarm Processing

Communication Remote Control

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Information Storage and Reports Sequence of Events Acquisition Data Calculations Special RTU Processing/Control

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Levels of Automation:Substation Level Automation

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Feeder level automation

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Customer level automation.

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. in half duplex mode and each operates independently of others. One circuit may be dedicated to single RTU, but the common and economical approach is to multi-drop or partyline several RTUs from a common communication circuit. The media for these circuits may be leased telephone circuits from a common carrier, private microwave. fiber optic cable systems, two-way cable TV, power line carrier, or even satellite. Polling and command requests and RTU responses are time-multiplexed on each circuit. Each circuit terminating at the master station is independently serviced on an asynchronous basis by the master station. Information rates per channel may range from 300 to 9600 bit& and are largely influenced by the measurement point count serviced by all RTUs sharing a common circuit. The most commonly used information rate is 1200 bit& using asynchronous byte-oriented message formats. The polling periodicity is established by the necessary response of using application functions and by human factor considerations. Where acquired data support closed control loops, such as feeders automatic generation control (AGC), the data sampling rate (DistrituOOn net....nj must be sufficient to maintain desired control loop response. For AGC this periodicity generally ranges between 2 and 6 s. For general operator monitoring of most system variables, an update period of about 10 s is generally acknowledged to be sufficient. Rapidly changing least significant numerals on CRT displays tend to be distracting to operators. Not all variables need to be acquired at the same period and, in fact, usually are not. The factor which usually establishes the basic RTU polling period is the desired response to unscheduled events or alarms. For electric system operations this period is on the order of 2-3s. Other information may be selectively acquired at each Figure 3: SCADA in Distribution System poll period or at multiples of the poll period A variation to fixed period polling is the round robin approach used by some European systems. Here, each RTUPolling Schemes: to-master message contains an end of message (EOM). SCADA systems intended for electric system operations When the master station detects the EOM the next RTU almost universally use a polling scheme between the central sharing the same communication line is then immediately master and individual RTUs. In communications polled. This results in continuous activity on the line with no engineering parlance the method is known as "Demand gaps of time. The individual point sampling rate is then Assignmentffime Division Multiple Access (DArrDMA)." influenced by the number of RTUs sharing the same line The master station controls all activity and RTUs respond and the number of points per RTU and whether or not only to polling requests. exception reporting is being used. Modern RTUs actually Figure 4 illustrates the most common communication scan the connected points at a high rate compared to the arrangement. master station poll period. When a master station poll Multiple two- or four-wire telephone-grade circuits radiate request is received by the RTU, the current values or status from the master. These communication circuits each operate stored in the RTU memory are fetched on a selective basis

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Paper for National Conference on Distribution Automation @CPRI Bangalore and transmitted to the master station. Polling requests may also contain various command and control requests. The RTU must distinguish these from information requests and respond accordingly.' A command sequence for circuit breaker operation is typical. Some form of select-checkoperate sequence is almost always used to avoid disoperation. SCADA systems intended for distributed data acquisition and control within a large substation or power plant may utilize a different polling strategy. Where all RTUs can be physically located within one or two thousand feet of each other, they may be connected to each other, the man-machine interface, and a host processor via local area network. Such arrangements permit great flexibility in communication between system elements or nodes. Instead of conventional sequential polling under the complete direction of the master station, local area network connected systems generally permit exchange of information directly between any two nodes on a random basis. Carrier Sense Multiple Access (CSMA),Token Ring ,or other schemes may be used. Figure 5 shows a simplified block diagram of a distributed system where communication can occur between any nodes at random basis. Network connected local SCADA. system where communications can occur between any nodes on a random basis.

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Figure 5 : Network Connected to local SCADA

scale span. The sign indicates the direction of flow since electric flow, in many instances, is bidirectional. Process Control applications, including water and gas utilities, are more likely to standardize on 4-2&mA input ranges. Status inputs are usually represented by a simple binary on-off state. In cases where mechanical devices change state slowly, for example, a motor-operated disconnect switch, three states are necessary: open-in transit-closed. This is accomplished with two limit switches which have four possible states: I) A open, B closed-switch open 2) A open, B open-switch in transit 3) A closed, B open-switch closed 4) A closed, 6 closed-invalid combination. Certain devices, such as circuit breakers with automatic reclosing activated, may operate and return to the original state in less time than one RTU poll or scan period. Operationally, it is important that such action be detected and reported to the master station. This is accomplished by change detection logic in the RTU which senses high-speed changes in status occurring between scans and conveys this fact by setting a change bit. Some SCADAs actually count and report the number of changes; detection of up to three changes is standard. Energy quantities, such as MWh, are derived from watt hour meters in the form of pulses-each pulse representing a specified number of MWh. The RTU counts the pulses in a register and reports the count to the master at designated intervals. In order to minimize overall electric system energy balance errors, a kwh register "freeze" command, is often broadcast simultaneously to all RTUs. The register counts are then requested by the master and saved in the master station historical files. Special RTU inputs or interfaces are occasionally required. These can take on many forms but the more common forms include binary coded decimal, pulse duration modulation, and serial ASCII character streams via an RS-232 port. Since RTUs must operate in the high-voltage electric sub-station/power plant environment, special design features must be included to prevent damage to the RTU, false data reporting, or disoperation. These features may include photo -optical isolation, varistors, and switched-capacitor inputs. The various schemes are tested against the IEEE Surge Withstand Capability (SWC) Standard 472-1974 for compliance.

Data Inputs SCADA systems intended for electric system operations are most frequently called on to monitor the following information from substations and power plants: Substations bus voltages line flows (MW, MYAR, A) transformer tap positions circuit breaker, switch, other device status alarms MW sequence-of events. unit generation MW and MY AR auxiliaries MW and MY AR unit MWh auxiliaries MWh station net MW, M'YAR unit maximum and control limits unit performance information gate position and limits (hydro) forcbay and tail-water levels (hydro).

Control Outputs SCADA systems intended for electric system operations are most frequently called on to provide control outputs to substations and power plants as follows: • Substations • circuit breaker operation • motorized switch control • tap changer transformer control • protective relay or scheme mode control • RTU internal register freeze control. Power Plants:-turbine-generator remote start-stop (hydro, gas turbine limit set (hydro) turbine-generator MW raise/lower turbine-generator MW set-point generator voltage NAR control. Discrete control outputs generally occur from interposing relays which momentarily close for a specific control action such as Circuit Breaker "trip:" The relay contact rating must be carefully sized to carry and

Power Plants Most magnitude inputs such as bus volts, MW, and MY AR originate in analog form. US. electric utilities have a de faCIO standard of 0 f l-mA input to the RTU representing the full

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Paper for National Conference on Distribution Automation @CPRI Bangalore interrupt the load which, most often, is another relay in a de control circuit. If ac control circuits are used the RTU interpose relay may be replaced with a TRIAC~ Generator MW is. r~motel.y set or adjusted in one of two ways: I ) by transmitting raise or lower pulses of variable duration and frequency of ?ccurrence to the turbine governor motor; these pulses adjust the governor s pee d setting and thus the generator output MW or 2) by transmission of a desired MW set point which results in an analog output from the RTU proportional to the desired MW. An external control loop, usually in the governor, then automatically adjusts the speed setting until the desired MW is achieved.

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Database Older SCADA systems tended to have fixed-format ?atabase~ where user programs required very explicit information about the database and its structure. This philosop.hy v:as easier for the database designer but substantially increased the complexity of maintaining the system as points were changed and new application programs added. With the advent of lower cost memories it has become easier and more attractive to incorporate various database management features into SCADA systems. These newer SCADA databases permit considerable independence betw~en the data acquisition function which updates the teal-time part of the database and the user programs which retrieve data from the database and save computed results back i~to t~e database. The newer databases are not rigidly fixed in size but can easily be expanded providing the physical memory is available. Design tradeoffs always exist between the degree of generalization in the database and speed of operation. Highly generalized database concepts as used in business applications, frequently have excessive compute overhead which makes them unsuitable for time critical real-rime use. Information contained in SCADA databa~es may be categorized into several distinct types: Real-Time: Measurement and status information which is periodically acquired via RTUs or entered by operators. On each update the old values are overwritten. The periodicity of update may vary from a few seconds to hours. Parametric: Parameter information is semi-fixed data which contain various attributes necessary to interpret real- time data. I.neluded .are high, low, and rate limits, scaling and offset information; areas of responsibility codes, scan rates, normal status, and many more. Calculated: Pseudo-points which are calculated from other points and then treated the same as real-rime data. An example of a calculated value would be the summation of two real-time values occurring at specified intervals. App~ica~ion: Information which is unique to specific applications. There may be constants, normal status, limits, stored messages, and more. An example would be stored message elements for an alarm processing function. It is important that system operators be made aware of data in ~vhich validity may be suspect. This is frequently accomplished by appending a quality code or flag to each data point .in the database. These codes can appear as symbols adjacent to displayed data or color changes to the displayed value which denote the "quality" of the data. Normal data are the default state where no quality code is usua I lydisplayed.A point which is out of scan and not beina updated, for example, would carry a code indicating that condition.

Man-Machine

Interface:

A Human-Machine Interface or HMI is the apparatus which presents process data to a human operator, and through which the human operator controls the process. The HMI industry was essentially born out of a need for a standardized way to monitor and to control multiple remote controllers, PLCs and other control devices. While a PLC does provide automated, pre-programmed control over a process, they are usually distributed across a plant, making it difficult to gather data from them manually. Historically PLCs had no standardized way to present information to an operator. The SCADA system gathers information from the PLCs and other controllers via some form of network, and combines and formats the information. An HMI may also be linked to a database, to provide trending, diagnostic data, and management information such as scheduled maintenance procedures, logistic information, detailed schematics for a particular sensor or machine, and .expertsystem troubleshooting guides. Since about 1998, virtually all major PLC manufacturers have offered integrated HMIISCADA systems, many of them using open and nonproprietary communications protocols. Numerous specialized third-party HMIISCADA packages, offering built-in compatibility with most major PLCs, have also entered the market, allowing mechanical engineers, electrical engineers and technicians to configure HMls themselves, without the need for a custom-made program written by a software developer Logs and Reports Log printing generally refers to the chronological print-ing of events as they occur. These events may be electric system alarms, internal SCADA system alarms, or operator-initiated actions. The format of log printouts is generally identical to alarm and event CRT summaries. Reports are pre-formatted documents that are produced at periodic intervals or by operator demand. Most often they are produced daily and show the results of system operations an hourly basis. The information source for reports is usually the stored historv file. • External Interfaces Increasingly the need arises to establish some form of information transfer between SCADA systems and other external systems. Examples of external interfaces include information exchange with: I) other systems arranged in a hierarchical order within the same utility, 2) adjacent utility SCADA or EMS systems, 3) pool control centers, 4) power brokering arrangements, 5) separate load management systems, 6) local PCs or PC networks, 7) corporate computers, 8) departmental computers such as system planning. The complexity of such interfaces varies widely. An elementary, but often practical approach, is to have one of the terminals simply emulate a serial printer and unidirectionally transfer information in a standard report format. At the other extreme is a multi-layer

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Paper for National Conference on Distribution Automation @CPRI Bangalore REALIZE MANY KEY ADVANTAGES TO PECO packet communication protocol based on well recognized standards. The CCITT X.2S standard, or variations of it, are gaining favor for Distributed Topology this application. For those situations where the other interfacing computer is local, the Ethernet standard is • Number of relays reduced by 75% useful. • Analog wiring reduced by 30% Message Protocols and Error Detection • Control wiring reduced by 50% Communications between the SCADA master and • Failures detected within seconds vs. at next RTUs for most conventional systems must be bit-serial maintenance interval using polling methods previously described. All • Breaker isolation and system restoration reduced communications, whether master to RTU or RTU to from hours to minutes master, occur in the form of messages where each message is composed of three parts: I) the header, 2) Enhanced System Topology information, and 3) the trailer. The header and trailer • Automatic fault data are normally fixed in length but the information is • Remote access to detailed event reports usually of variable length with an upper bound before a • View oscillography and digitals for timing details new message is created. and operation analysis The outgoing header contains synchronizing bits, the • Make system improvement recommendations RTU address. and some form of function code. The based on data function code informs the RTU of the type of • Verify auxiliary equipment (trip coil) information which is to follow and is frequently 8 bits • Automated system operation supervision for in length. The trailer ordinarily contains a security code breaker closing for the detection of transmission-induced errors and is • Reduced maintenance frequently a Bose-Chaudhuri-Hocquenghern (BCH) • Increased personnel safety code or a Cyclic Redundancy Check (CRC). A security • "Fast Trip" scheme provides instantaneous tripping code design objective is to ensure the probability of during hot-line maintenance acceptance of a message received in error is less than I • Flashover detection for open switches in 1010 for a maximum received bit-error rate of I in 104• The information part of the message is often byte oriented and variable in length. VI. DISTRIBUTION AUTOMATION: GROWTH AND CHALLENGES IN DEVELOPED COUNTRIES V. SCADA IN DISTRIBUTION [ 10

SYSTEM: CASESTUDY

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The idea of distribution automation began in I970s. The motivation at that time was to use the evolving computer and communications technology to improve operating performance of distribution systems. Since then, the growth of distribution automation has been dictated by the level of sophistication of existing monitoring. control, and communication technologies; and performance and cost of available equipment. Although distribution systems are a significant part of power systems, advances in distribution control technology have lagged considerably behind advances in generation and transmission control . Small pilot projects were implemented by a few utilities to test the concept of distribution automation in the I970s. In the I980s. there were several major pilot projects. By the 1990s. the DA technology had matured and that resulted in several large and many small projects at various utilities. Automation allows utilities to implement flexible control of distribution systems, which can be used to enhance efficiency, reliability, and quality of electric service. Flexible control also results in more effective utilization and life-extension of the existing distribution system infrastructure. Many utilities are contemplating providing performance-based rates to their customers. They would be willing to pay compensation to the customers if the performance falls below a minimum level. Such actions will allow utilities to brace for the upcoming competition from other parties interested in supplying power to the.customers. Although higher reliability and quality are the goals of the utilities, they would like to accomplish this while optimizing the resources. Another goal for a utility should be

Case Study Of PECO Energy Co. Here case study of a project consisting of implementation of SCADA for distribution Automation within a substation is considered. This project is renovated for PECO energy co. which provides automation for distribution of electric power. PECO Energy Co. is an electric utility that serves the metropolitan Philadelphia area. Like many other utilities today. PECO needed a better way, both locally and remotely. to monitor, control, diagnose, and maintain cquipment in the substation to reduce operating costs and provide improved customer service. These demands to increase productivity and reduce costs translated into the need to collect and act on decision-making information. In addition, this scheme would minimize maintenance cost through the use of self-checking and relay setting veriJication. The new economical, streamlined design allows for primary and backup redundancy for all single contingency fault conditions, while intuitively replicating existing electromechanical protection philosophies. The microprocessor relays' new digital communications capabilities, incorporated into a substation integration (SI) system. allow exceptionally fast and reliable SCADA control. status and metering for all interrupting devices, lockout relays, and motor operated disconnects (MOD)s. 6

Paper for National Conference on Distribution Automation @CPRI Bangalore improvement in system efficiency by reducing system losses. The functions that can be automated in distribution systems can be classified into two categories, namely, monitoring functions and control functions. Monitoring functions are those needed to record meter readings at different locations in the system, the system status at different locations in the system, and events of abnormal conditions. The data monitored at the system level are not only useful for day-to-day operations but also for system planning. Distribution supervisory control and data acquisition (DSCADA) systems perform some of these monitoring functions. The control functions are related to switching operations, such as switching a capacitor, or reconfiguring feeders. The function that is the most popular among the utilities is fault location and service restoration or outage management. This function directly impacts the customers as well as the system reliability. Presently, worldwide research and development efforts are focused in following areas to make distribution automation more intelligent and cost effective in order to accomplish the objective of full-scale unbundling of power systems. • Power system communication protocol to achieve interoperability • Communication system to make it commercially viable o Switchgears and transformers to make them self intelligent through IEDs o Intelligent Remote Terminal Units (RTUs) • Intelligent instrumentation system • Power system algorithm to provide quick and accurate control decision Research and development efforts are being carried out worldwide for full integration of AM/FM, AMR, GIS, and IT with distribution automation to realize overall Distribution Management System (DMS). Looking the future needs, few universities in the world have already introduced courses on distribution automation and related areas. DISTRIBUTION CHALLENGES

AUTOMATION: IN DEVELOPING

GROWTH COUNTRIES

VII.

VIII. CONCLUSION The SCADA system has evolved from a pure SCADA application to a Distribution Management System for the 22 kV and 6.6 kV network, supporting the roles of network operation and planning by minimizing transmission losses and also by improving the power quality by minimizing voltage sags. It has helped to bring about a dramatic drop in the number of blackouts caused by 22 kV outages because of the network ring configurations, and to slash the average outage time of a 22 kV power failure to a fraction of what it used to be. Its latest development phase will be the incorporation of probably the world's first real-rime Expert System for its disturbance analysis, network restoration, load transfer and switching check functions.

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India is one of the developing countries. In India, the generation and transmission networks have been expanded in a planned manner using modern technology and software tools. However, the distribution systems have grown in an unplanned manner resulting in high system losses in addition to poor quality of supply. Efficient operation and maintenance of distribution system in India is hampered by non-availability of system topological information, current health information of the distribution components like distribution transformers and feeders, historical data etc. The other reasons are the lack of use of efficient tools for operational planning and advanced methodology for quick detection of fault, isolation of the faulty section and service restoration etc. Currently, fault detection, isolation and service restoration takes a long time causing the interruption of supply for a longer duration. Manual meter reading, delay in billing, faulty and inaccurate metering, tampering of meters and pilferage of electricity are some of the main reasons for poor return of revenue to electricity utilities in India.

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RESEARCH

Across the world, vendors have brought out Distribution Automation (DA) technology in a fragmented manner. No indigenous effort appears to be made in offering complete so\.ution of the Distribution Automation system starting from development of various components tilI the integration of the complete distribution automation systems. The future research work should be aimed at developing indigenous know-how of full scale Distribution Automation system, which can cover from primary substations to consumer level intelIigent automation. The future research work for power distribution automation is expected into following broad areas. • Customer level intelligent automation system • Computer aided monitoring and control of Distribution Transformers • 'Substation and feeder level automation • Data communication system for Distribution Automation •• Distribution Control Centre (DCC) software • Pilot level demonstration projects

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DISTRIBUTION AUTOMATION: WORK IN FUTURE [9]

"The Implementation And Evolution of SCADA System For A Large Distribution Network & substation." IEEE technical paper S.S. Rao. " Switchgear & Protection" Horst Ebenhoh, "Evolutionary Architectures for SCADA and EMS Systems" Technical Papers of the IEEE Conference. IEEE Tutorial Course-Fundamentals of Supervisory Control Systems. IEEE Power Society, PuM. 81 EHO 1883 PWR Mini S. Thomas, Senior Member, IEEE, Parmod Kumar, and Vinny K. Chandna:' "Design, Development, and Commissioning of a Supervisory Control and Data Acquisition (SCADA) Laboratory for Research and Training" N.D. Sarma, " Supervisory Control & Data Acquisition Systems" IEEE technical paper. P. Kumar, V. K. Chandna, and M. S. Thomas, "Intelligent algorithm forpre-processing multiple data at RTU," IEEE Trans. Power Syst., vol. 18,pp. 1566-1572, Nov. 2003. S.-1. Huang and Chih-Chieh, "Application of ATM -BASED network for an integrated distribution SCADA-GIS system," IEEE Trans. Power Syst., vol. 17, pp. 8Q,,86, Feb. 2002 W. Chainey and M. R. Block, "Recent Advances in Master Station Architecture". IEEE SCADA Applications in Power, Vol. 7, No.'2, 2004, pp. 25-27. David Dolezilek, "Case Study Of A Large Transmission And Distribution Substation Automation Project"

2 Paper for National Conference on Distribution Automation @CPRI Bangalore BIOGRAPHIES

.P.V.chopade (M'2003) born in Maharashtra on 18"Decb 1980,completed his Bachelors Degree in Electrical Engg from Govt.college of Engineering Amravati in July 1998 and Masters Degree in Electrical Engg from Govt.college of Engineering Pune, Pune University with firs! Rank in University in December 1999. He is presently working as lecturer in Electrical Engineering in Bharati Vidyapeeth University College of Engineering Pune. He had 4 years of teaching experience. His major field of interest is SCADA and Computer Applications in Power system and Power Electronics. As a IEEE member he worked as organizing committee member for ACE·2003 IEEE Conference held at Pune, he is IEEE student branch mentor of BVUCOE Pune and he is also Life Member ISTE. He presented research papers at various national and international conferences in India and abroad in Australia.

D.G.Bharadwaj (M'1978) born in Maharashtra on 3"'Feb 1941,compleled his Bachelors Degree in Electrical Engg from V.R.C.E.,Nagpur University in 1964, Masters Degree and Ph.D in Electrical Engg from University of Roorkee (India) now 1.1.T. Roorkee .He retired as Principal Govt.college of Engineering Auraganbad. He also worked as Principal at Atharva college of Engg. Mumbai. He is presently working as Professor of Electrical Engineering and Director of Research and Development Cell in Bharati Vidyapeeth University College of Engineering Pune. He has 40 years of teaching experience. His major field of interest is Computer Applications in Power system and Advanced Electrical Machines. He published more than 75 research papers at different national and international conferences and journals

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