PROJECT REPORT ON SMART GRID

SMART GRID GITA,BBSR

ABSTRACT Today's alternating current power grid evolved after 1896, based in part on Nikola Tesla's design published in 1888 (see War of Currents). At that time, the grid was conceived as a centralized unidirectional system of electric power transmission, electricity distribution, and demand-driven control. In the 20th century power grids originated as local grids that grew over time, and were eventually interconnected for economic and reliability reasons. By the 1960s, the electric grids of developed countries had become very large, mature and highly interconnected, with thousands of 'central' generation power stations delivering power to major load centres via high capacity power lines which were then branched and divided to provide power to smaller industrial and domestic users over the entire supply area. The topology of the 1960s grid was a result of the strong economies of scale of the current generation technology: large coal-, gas- and oil-fired power stations in the 1 GW (1000 MW) to 3 GW scale are still found to be cost-effective, due to efficiency-boosting features that can be cost effectively added only when the stations become very large. A smart grid is a digitally enabled electrical grid that gathers, distributes, and acts on information about the behavior of all participants (suppliers and consumers) in order to improve the efficiency, importance, reliability, economics, and sustainability of electricity services

[1]

SMART GRID GITA,BBSR

INTRODUCTION Historical development of the electricity grid Today's alternating current power grid evolved after 1896, based in part on Nikola Tesla's design published in 1888. At that time, the grid was conceived as a centralized unidirectional system of electric power transmission, electricity distribution, and demand-driven control. In the 20th century power grids originated as local grids that grew over time, and were eventually interconnected for economic and reliability reasons. By the 1960s, the electric grids of developed countries had become very large, mature and highly interconnected, with thousands of 'central' generation power stations delivering power to major load centres via high capacity power lines which were then branched and divided to provide power to smaller industrial and domestic users over the entire supply area. The topology of the 1960s grid was a result of the strong economies of scale of the current generation technology: large coal-, gas- and oil-fired power stations in the 1 GW (1000 MW) to 3 GW scale are still found to be cost-effective, due to efficiency-boosting features that can be cost effectively added only when the stations become very large. Power stations were located strategically to be close to fossil fuel reserves (either the mines or wells themselves, or else close to rail, road or port supply lines). Siting of hydro-electric dams in mountain areas also strongly influenced the structure of the emerging grid. Nuclear power plants were sited for availability of cooling water. Finally, fossil-fired power stations were initially very polluting and were sited as far as economically possible from population centres once electricity distribution networks permitted it. By the late 1960s, the electricity grid reached the overwhelming majority of the population of developed countries, with only outlying regional areas remaining 'off-grid'.

[2]

SMART GRID GITA,BBSR

Origin of the term 'smart grid' The term smart grid has been in use since at least 2005, when it appeared in the article "Toward A Smart Grid" of Amin and Wallenberg. The term had been used previously and may date as far back as 1998. There are a great many smart grid definitions, some functional, some technological, and some benefitsoriented. A common element to most definitions is the application of digital processing and communications to the power grid, making data flow and information management central to the smart grid. Various capabilities result from the deeply integrated use of digital technology with power grids, and integration of the new grid information flows into utility processes and systems is one of the key issues in the design of smart grids. Electric utilities now find themselves making three classes of transformations: improvement of infrastructure, called the strong grid in China; addition of the digital layer, which is the essence of the smart grid; and business process transformation, necessary to capitalize on the investments in smart technology. Much of the modernization work that has been going on in electric grid modernization, especially substation and distribution automation, is now included in the general concept of the smart grid, but additional capabilities are evolving as well.

[3]

SMART GRID GITA,BBSR

SMART GRID Smart grid refers to the next generation electric power network that makes use of IT and high technologies. Compared to the telecommunication network, the electric power network has not developed remarkably in terms of creating innovative technologies. However, smart grid by revolutionizing the electric power network and being almost as powerful as the internet, is attracting many attentions among various industries. Smart grid is a system that enables two-way communications in between consumers and electric power companies. In a smart grid system consumer‘s information is received by the electric power companies in order to provide the most efficient electric network operations. In addition to the efficient operations of a power plant, smart grids also make it possible to control power demand and distributed energy, including renewable energies. By installing an intelligent meter (smart meter) on the consumer side, especially households, monitoring the use of energy becomes much easier and even helps to reduce carbon dioxide emissions.

[4]

SMART GRID GITA,BBSR

A smart grid delivers electricity from supplier to consumers using two- way digital technology to control appliances at consumers‘ homes to save energy, reduce cost and increase reliability and transparency. It overlays the electricity distribution grid with an information and net metering system. Power travels from the power plant to your house through an amazing system called the power distribution grid. Such a modernized electricity networks is being promoted by many governments as a way of addressing energy independences, global warming and emergency resilience issues. Smart meters may be part of smart grid, but alone do not constitute a smart grid.

Overview of smart grid

A smart grid includes an intelligent monitoring system that keeps track of all electricity flowing in the system. It also incorporates the use of superconductive transmission lines for less power loss, as well as the capability of the integrating renewable electricity such as solar and wind. When power is least expensive the user can allow the smart grid to turn on selected home appliances such as washing machines or factory processes that can run at arbitrary hours. At peak times it could turn off selected appliances to reduce demand.

[5]

SMART GRID GITA,BBSR

Smart Grid And it’s Need Understanding the need for smart grid requires acknowledging a few facts about our infrastructure. The power grid is the backbone of the modern civilization, a complex society with often conflicting energy needs-more electricity but fewer fossil fuels, increased reliability yet lower energy costs, more secure distribution with less maintenance, effective new construction and efficient disaster reconstruction. But while demand for electricity has risen drastically, its transmission is outdated and stressed. The bottom line is that we are exacting more from a grid that is simply not up to the task.

POWER SYSTEM

[6]

SMART GRID GITA,BBSR

How“smart”should be a powergrid The utilities get the ability to communicate with and control end user hardware, from industrial- scale air conditioner to residential water heaters. They use that to better balance supply and demand, in part by dropping demand during peak usage hours. Taking advantages of information technology to increase the efficiency of the grid, the delivery system, and the use of electricity at the same time is itself a smart move. Simply put, a smart grid combined with smart meters enables both electrical utilities and consumer to be much more efficient. A smart grid not only moves electricity more efficiently in geographic terms, it also enables electricity use to be shifted overtime-for example, from period of peak demand to those of off-peak demand. Achieving this goals means working with consumers who have ―smart meters‖ to see exactly how much electricity is being used at any particular time. This facilitates two-way communication between utility and consumer. So they can cooperate in reducing peak demand in a way that it‘s advantageous to both. And it allow to the use of two way metering so that customer who have a rooftop solar electric panel or their own windmill can sell surplus electricity back to the utility.

1. Intelligent – Capable of sensing system overloads and rerouting power to prevent or minimize a potential outage; of working autonomously when conditions required resolution faster than humans can respond and co-operatively in aligning the goals of utilities, consumers and regulators.

2. Efficient – Capable of meeting efficient increased consumer demand without adding infrastructure.

3. Accommodating – Accepting energy from virtually any fuel source including solar and wind as easily and transparently as coal and natural gas: capable of integrating any and all better ideas and technologies – energy storage technologies. For e.g.- as they are market proven and ready to come online.

[7]

SMART GRID GITA,BBSR

4. Motivating – Enable real-time communication between the consumer and utility, so consumer can tailor their energy consumption based on individual preferences, like price and or environmental concerns.

5. Resilient – Increasingly resistant to attack and natural disasters as it becomes more decentralization and reinforced with smart grid security protocol.

6. Green – Slowing the advance of global climate change and offering a genuine path towards significant environmental improvement.

[8]

SMART GRID GITA,BBSR

Features of the smart grid The smart grid represents the full suite of current and proposed responses to the challenges of electricity supply. Because of the diverse range of factors, there are numerous competing taxonomies, and no agreement on a universal definition. Nevertheless, one possible categorisation is given here.

 Reliability The smart grid will make use of technologies that improve fault detection and allow self-healing of the network without the intervention of technicians. This will ensure more reliable supply of electricity, and reduced vulnerability to natural disasters or attack. Although multiple routes are touted as a feature of the smart grid, the old grid also featured multiple routes. Initial power lines in the grid were built using a radial model, later connectivity was guaranteed via multiple routes, referred to as a network structure. However, this created a new problem: if the current flow or related effects across the network exceed the limits of any particular network element, it could fail, and the current would be shunted to other network elements, which eventually may fail also, causing a domino effect. See power outage. A technique to prevent this is load shedding by rolling blackout or voltage reduction (brownout).

 Flexibility in network topology Next-generation transmission and distribution infrastructure will be better able to handle possible bidirection energy flows, allowing for distributed generation such as from photovoltaic panels on building roofs, but also the use of fuel cells, charging to/from the batteries of electric cars, wind turbines, pumped hydroelectric power, and other sources. Classic grids were designed for one-way flow of electricity, but if a local subnetwork generates more power than it is consuming, the reverse flow can raise safety and reliability issues. A smart grid aims to manage these situations.

[9]

SMART GRID GITA,BBSR

 Efficiency Numerous contributions to overall improvement of the efficiency of energy infrastructure is anticipated from the deployment of smart grid technology, in particular including demand-side management, for example turning off air conditioners during short-term spikes in electricity price. The overall effect is less redundancy in transmission and distribution lines, and greater utilisation of generators, leading to lower power prices

 Load adjustment The total load connected to the power grid can vary significantly over time. Although the total load is the sum of many individual choices of the clients, the overall load is not a stable, slow varying, average power consumption. Imagine the increment of the load if a popular television program starts and millions of televisions will draw current instantly. Traditionally, to respond to a rapid increase in power consumption, faster than the start-up time of a large generator, some spare generators are put on a dissipative standby mode .A smart grid may warn all individual television sets, or another larger customer, to reduce the load temporarily (to allow time to start up a larger generator) or continuously (in the case of limited resources). Using mathematical prediction algorithms it is possible to predict how many standby generators need to be used, to reach a certain failure rate. In the traditional grid, the failure rate can only be reduced at the cost of more standby generators. In a smart grid, the load reduction by even a small portion of the clients may eliminate the problem.

 Peak curtailment/leveling and time of use pricing To reduce demand during the high cost peak usage periods, communications and metering technologies inform smart devices in the home and business when energy demand is high and track how much electricity is used and when it is used. It also gives utility companies the ability to reduce consumption by communicating to devices directly in order to prevent system overloads. An example would be a utility reducing the usage of a group of electric vehicle charging stations. To motivate them to cut back use and perform what is called peak curtailment or peak leveling, prices of electricity are increased during high demand periods, and decreased during low demand periods. It is thought that consumers and businesses will tend to consume less during high demand periods if it is possible for consumers and consumer devices to be aware of the high price premium for using electricity at peak periods. This could mean making trade-offs such as cooking dinner at 9 pm instead of 5 pm. When businesses and consumers see a direct economic benefit of using energy at offpeak times become more energy efficient, the theory is that they will include [10]

SMART GRID GITA,BBSR

energy cost of operation into their consumer device and building construction decisions. See Time of day metering and demand response. According to proponents of smart grid plans, this will reduce the amount of spinning reserve that electric utilities have to keep on stand-by, as the load curve will level itself through a combination of "invisible hand" free-market capitalism and central control of a large number of devices by power management services that pay consumers a portion of the peak power saved by turning their devices off.

 Sustainability The improved flexibility of the smart grid permits greater penetration of highly variable renewable energy sources such as solar power and wind power, even without the addition of energy storage. Current network infrastructure is not built to allow for many distributed feed-in points, and typically even if some feed-in is allowed at the local (distribution) level, the transmission-level infrastructure cannot accommodate it. Rapid fluctuations in distributed generation, such as due to cloudy or gusty weather, present significant challenges to power engineers who need to ensure stable power levels through varying the output of the more controllable generators such as gas turbines and hydroelectric generators. Smart grid technology is a necessary condition for very large amounts of renewable electricity on the grid for this reason.

 Market-enabling The smart grid allows for systematic communication between suppliers (their energy price) and consumers (their willingness-to-pay), and permits both the suppliers and the consumers to be more flexible and sophisticated in their operational strategies. Only the critical loads will need to pay the peak energy prices, and consumers will be able to be more strategic in when they use energy. Generators with greater flexibility will be able to sell energy strategically for maximum profit, whereas inflexible generators such as base-load steam turbines and wind turbines will receive a varying tariff based on the level of demand and the status of the other generators currently operating. The overall effect is a signal that awards energy efficiency, and energy consumption that is sensitive the time-varying limitations of the supply. At the domestic level, appliances with a degree of energy storage or thermal mass (such as refrigerators, heat banks, and heat pumps) will be well placed to 'play' the market at seek to minimise energy cost by adapting demand to the lower-cost energy support periods. This is an extension of the dual-tariff energy pricing mentioned above.

[11]

SMART GRID GITA,BBSR

 Demand response support Demand response support allows generators and loads to interact in an automated fashion in real time, coordinating demand to flatten spikes. Eliminating the fraction of demand that occurs in these spikes eliminates the cost of adding reserve generators, cuts wear and tear and extends the life of equipment, and allows users to cut their energy bills by telling low priority devices to use energy only when it is cheapest. Currently, power grid systems have varying degrees of communication within control systems for their high value assets, such as in generating plants, transmission lines, substations and major energy users. In general information flows one way, from the users and the loads they control back to the utilities. The utilities attempt to meet the demand and succeed or fail to varying degrees (brownout, rolling blackout, uncontrolled blackout). The total amount of power demand by the users can have a very wide probability distribution which requires spare generating plants in standby mode to respond to the rapidly changing power usage. This one-way flow of information is expensive; the last 10% of generating capacity may be required as little as 1% of the time, and brownouts and outages can be costly to consumers. Latency of the data flow is a major concern, with some early smart meter architectures allowing actually as long as 24 hours delay in receiving the data, preventing any possible reaction by either supplying or demanding devices.

 Platform for advanced services As with other industries, use of robust two-way communications, advanced sensors, and distributed computing technology will improve the efficiency, reliability and safety of power delivery and use. It also opens up the potential for entirely new services or improvements on existing ones, such as fire monitoring and alarms that can shut off power, make phone calls to emergency services, etc.

 Provision megabits, control power with kilobits, sell the rest The amount of data required to perform monitoring and switching your appliances off automatically is very small compared with that already reaching even remote homes to support voice, security, and Internet and TV services. Many smart grid bandwidth upgrades are paid for by over-provisioning to also support consumer services, and subsidizing the communications with energyrelated services or subsidizing the energy-related services, such as higher rates [12]

SMART GRID GITA,BBSR

during peak hours, with communications. This is particularly true where governments run both sets of services as a public monopoly, e.g. in India. Because power and communications companies are generally separate commercial enterprises in North America and Europe, it has required considerable government and large-vendor effort to encourage various enterprises to cooperate. Some, like Cisco, see opportunity in providing devices to consumers very similar to those they have long been providing to industry. Others, such as Silver Spring Networks or Google, are data integrators rather than vendors of equipment. While the AC power control standards suggest powerline networking would be the primary means of communication among smart grid and home devices, the bits may not reach the home via Broadband over Power Lines (BPL) initially but by fixed wireless. This may be only an interim solution, however, as separate power and data connections defeats full control.

 Technology The bulk of smart grid technologies are already used in other applications such as manufacturing and telecommunications and are being adapted for use in grid operations. In general, smart grid technology can be grouped into five key areas.

 Integrated communications Some communications are up to date, but are not uniform because they have been developed in an incremental fashion and not fully integrated. In most cases, data is being collected via modem rather than direct network connection. Areas for improvement include: substation automation, demand response, distribution automation, supervisory control and data acquisition (SCADA), energy management systems, wireless mesh networks and other technologies, power-line carrier communications, and fiber-optics. Integrated communications will allow for real-time control, information and data exchange to optimize system reliability, asset utilization, and security.

 Sensing and measurement Core duties are evaluating congestion and grid stability, monitoring equipment health, energy theft prevention, and control strategies support. Technologies include: advanced microprocessor meters (smart meter) and meter reading equipment, wide-area monitoring systems, dynamic line rating (typically based on online readings by Distributed temperature sensing combined with Real time thermal rating (RTTR) systems), electromagnetic signature measurement/analysis, time-of-use and real-time pricing tools, advanced switches and cables, backscatter radio technology, and Digital protective relays. [13]

SMART GRID GITA,BBSR

 Smart meters A smart grid replaces analog mechanical meters with digital meters that record usage in real time. Smart meters are similar to Advanced Metering Infrastructure meters and provide a communication path extending from generation plants to electrical outlets (smart socket) and other smart gridenabled devices. By customer option, such devices can shut down during times of peak demand.

 Phasor measurement units High speed sensors called PMUs distributed throughout their network can be used to monitor power quality and in some cases respond automatically to them. Phasors are representations of the waveforms of alternating current, which ideally in real-time, are identical everywhere on the network and conform to the most desirable shape. In the 1980s, it was realized that the clock pulses from global positioning system (GPS) satellites could be used for very precise time measurements in the grid. With large numbers of PMUs and the ability to compare shapes from alternating current readings everywhere on the grid, research suggests that automated systems will be able to revolutionize the management of power systems by responding to system conditions in a rapid, dynamic fashion. A wide-area measurement system (WAMS) is a network of PMUS that can provide real-time monitoring on a regional and national scale. Many in the power systems engineering community believe that the Northeast blackout of 2003 would have been contained to a much smaller area if a wide area phasor measurement network was in place.

 Advanced components Innovations in superconductivity, fault tolerance, storage, power electronics, and diagnostics components are changing fundamental abilities and characteristics of grids. Technologies within these broad R&D categories include: flexible alternating current transmission system devices, high voltage direct current, first and second generation superconducting wire, high temperature superconducting cable, distributed energy generation and storage devices, composite conductors, and ―intelligent‖ appliances.

[14]

SMART GRID GITA,BBSR

 Advanced control Power system automation enables rapid diagnosis of and precise solutions to specific grid disruptions or outages. These technologies rely on and contribute to each of the other four key areas. Three technology categories for advanced control methods are: distributed intelligent agents (control systems), analytical tools (software algorithms and high-speed computers), and operational applications (SCADA, substation automation, demand response, etc.). Using artificial intelligence programming techniques, Fujian power grid in China created a wide area protection system that is rapidly able to accurately calculate a control strategy and execute it.The Voltage Stability Monitoring & Control (VSMC) software uses a sensitivity-based successive linear programming method to reliably determine the optimal control solution

 Improved interfaces and decision support Information systems that reduce complexity so that operators and managers have tools to effectively and efficiently operate a grid with an increasing number of variables. Technologies include visualization techniques that reduce large quantities of data into easily understood visual formats, software systems that provide multiple options when systems operator actions are required, and simulators for operational training and ―what-if‖ analysis.

 Smart power generation Smart power generation is a concept of matching electricity production with demand using multiple identical generators which can start, stop and operate efficiently at chosen load, independently of the others, making them suitable for base load and peaking power generation. Matching supply and demand, called load balancing, is essential for a stable and reliable supply of electricity. Shortterm deviations in the balance lead to frequency variations and a prolonged mismatch results in blackouts. Operators of power transmission systems are charged with the balancing task, matching the power output of the all the generators to the load of their electrical grid. The load balancing task has become much more challenging as increasingly intermittent and variable generators such as wind turbines and solar cells are added to the grid, forcing other producers to adapt their output much more frequently than has been required in the past.First two dynamic grid stability power plants utilizing the concept has been ordered by Elering and will be built by Wärtsilä in Kiisa, Estonia. Their purpose is to "provide dynamic generation capacity to meet sudden and unexpected drops in the electricity supply." They are scheduled to be ready during 2013 and 2014, and their total output will be 250 MW. [15]

SMART GRID GITA,BBSR

Economics of “SMART GRID”  Market outlook : In 2009, the US smart grid industry was valued at about $21.4 billion – by 2014, it will exceed at least $42.8 billion. Given the success of the smart grids in the U.S., the world market is expected to grow at a faster rate, surging from $69.3 billion in 2009 to $171.4 billion by 2014. With the segments set to benefit the most will be smart metering hardware sellers and makers of software used to transmit and organize the massive amount of data collected by meters.

 General economic developments : As customers can choose their electricity suppliers, depending on their different tariff methods, the focus of transportation costs will be increased. Reduction of maintenance and replacements costs will stimulate more advanced control. A smart grid precisely limits electrical power down to the residential level, network small-scale distributed energy generation and storage devices, communicate information on operating status and needs, collect information on prices and grid conditions, and move the grid beyond central control to a collaborative network.

 US and UK savings estimates and concerns : One United States Department of Energy study calculated that internal modernization of US grids with smart grid capabilities would save between 46 and 117 billion dollars over the next 20 years. As well as these industrial modernization benefits, smart grid features could expand energy efficiency beyond the grid into the home by coordinating low priority home devices such as water heaters so that their use of power takes advantage of the most desirable energy sources. Smart grids can also coordinate the production of power from large numbers of small power producers such as owners of rooftop solar panels — an arrangement that would otherwise prove problematic for power systems operators at local utilities. One important question is whether consumers will act in response to market signals. In the UK, where consumers have had a choice of supply company from which to purchase electricity since 1998, almost half have stayed with their existing supplier, despite the fact that there are significant differences in the prices offered by a given electricity supplier. Where consumers switch an estimated 27-38% of consumers are worse off as a result. [16]

SMART GRID GITA,BBSR

Another concern is that the cost of telecommunications to fully support smart grids may be prohibitive. A less expensive communication mechanism is proposed using a form of "dynamic demand management" where devices shave peaks by shifting their loads in reaction to grid frequency. Grid frequency could be used to communicate load information without the need of an additional telecommunication network, but it would not support economic bargaining or quantification of contributions. Although there are specific and proven smart grid technologies in use, smart grid is an aggregate term for a set of related technologies on which a specification is generally agreed, rather than a name for a specific technology. Some of the benefits of such a modernized electricity network include the ability to reduce power consumption at the consumer side during peak hours, called demand side management; enabling grid connection of distributed generation power (with photovoltaic arrays, small wind turbines, micro hydro, or even combined heat power generators in buildings); incorporating grid energy storage for distributed generation load balancing; and eliminating or containing failures such as widespread power grid cascading failures. The increased efficiency and reliability of the smart grid is expected to save consumers money and help reduce CO2 emissions.

[17]

SMART GRID GITA,BBSR

Enabling Technology The bulk of smart grid technologies are already used in other applications such as manufacturing and telecommunications and are being adapted for use in grid operations. In general, smart grid technology can be grouped into five key areas

I.

Integrated communications

Some communications are up to date, but are not uniform because they have been developed in an incremental fashion and not fully integrated. In most cases, data is being collected via modem rather than direct network connection. Areas for improvement include: substation automation, demand response, distribution automation, supervisory control and data acquisition (SCADA), energy management systems, wireless mesh networks and other technologies, power- line carrier communication s and fiber-optics. Integrated communication will allow for real time control, information and data exchange to optimize system reliability, asset utilization, and security.

II. Sensing and measurement Core duties are evaluating congestion and grid stability, monitoring equipment health, energy theft prevention, and control strategies support. Technologies include: advanced microprocessor meters (smart meter) and meter reading equipment, wide-area monitoring system, dynamic line rating(typically based on online reading by distributed temperature sensing combined with Real time thermal rating (RTTR) systems), electromagnetic signature measurement/analysis, time-of-use and real-time pricing tools, advanced switches and cables, backscatter radio technology, and Digital protective relays.

[18]

SMART GRID GITA,BBSR

III. Smart meters A smart grid replaces analog mechanical meters with digital meters that record usage in real time. Smart meters are similar to Advanced Metering Infrastructure meters and provide a communication path extending from generation plants to electrical outlets (smart socket) and other smart gridenabled devices. By customer option, such devices can shut down during times of peak demand.

IV. Advanced components Innovations in superconductivity, fault tolerance, storage, power electronics, and diagnostics components are changing fundamental abilities and characteristics of grids. Technologies within these broad R&D categories include: flexible alternating current transmission system devices, high voltage direct current, first and second generation superconducting wire, high temperature superconducting cable, distributed energy generation and storage devices, composite conductors, and ―intelligent‖ appliances.

[19]

SMART GRID GITA,BBSR

ENERGY CONSERVATION

TECHNIOUES  ENERGY CONSERVATION IN TRANSMISSION SYSTEM: Transformer is a static device. It does not have any moving parts. So, a transformer is free from mechanical and frictional losses. Thus, it faces only electrical losses and magnetic losses. Hence the efficiency of conventional transformer is high around 95-98%.

Thus, energy conservation opportunities for transformer are available only in design and material used. Also optimizing loading of transformer can increase efficiency of system.

 ENERGY CONSERVATION TECHNIQUES IN TRANSFORMER OPTIMIZATION OF LOADING OF TRANSFORMER

The environmental protection agency (EPA) brought study report that nearly 61 billion K WH of electricity is wasted in each year only as transformer losses. Study of typical grid system showed that, power transformer contributes nearly 40% to 50% of total transmission and distribution losses. Maintaining maximum efficiency to occur at 38% loading (as recommended by REC), the overall efficiency of transformer can be increased and its losses can be reduced. The load loss may be even reduced by using thicker conductors . Transformer ratings

Reduction in losses at 38% loading

25 KVA

685-466W

63KVA

1235-844W

100KVA

1760-1196W

[20]

SMART GRID GITA,BBSR

 IMPROVISION IN DESIGN AND MATERIAL OF TRANSFORMER This is nothing but the reducing No-Load losses or Core Losses. They can be reduced by following methods:-

1) BY USING ENERGY EFFICIENT TRANSFORMERBy using superior quality or improved grades of CRGO (Cold Rolled Grain Oriented) laminations, the no-load losses can be reduced to 32%.

2) BY USING AMORPHOUS TRANSFORMER Transformer with superior quality of core material i.e. amorphous alloy is called

Amorphous Transformers. Amorphous alloy is made up of Iron-boron-silicon alloy. The magnetic core of this transformer is made with amorphous metal, which is easily magnetized / demagnetized. Typically, core loss can be 70–80% less than its molten metal mixture when cooled to solid state at a very high speed rate, retain a random atomic structure that is not crystalline. This is called Amorphous.

[21]

SMART GRID GITA,BBSR

Amorphous transformer

 ENERGY CONSERVATION IN TRANSMISSION LINE:Transmission losses can be reduced as follows:1) BY REDUCING RESISTANCE -

Losses are directly proportional to I2r in conductor. So, if we reduce ‗R‘ from this surely the losses will be reduced. For this we can use stranded or bundled conductors or ACSR conductors. And even this method is been adopted and also successful.

ACC

ACSR Conductor [22]

SMART GRID GITA,BBSR

2) BY CONTROLLING VOLTAGE LEVELS -

This can be done by following methods1. by using voltage controllers 2. by using voltage stabilizer

3. By using power factor controller

AWRENESS IN CONSUMERS This is one of most important and useful/helpful for energy conservation. This can be done by asking consumer to make use of energy efficient equipments, by giving seminar about energy conservation and make them aware and understand about the happening and there advantages and disadvantages etc. Effective use of smart grid technologies by customer helps utilities –  Optimizes grid use.  Improve grid efficiency and security.  Better align demand with supply constraints & grid congestion.  Enable distributed generation (especially from renewable sources)

[23]

SMART GRID GITA,BBSR

ENERGY CONSERVATION IN DISTRIBUTION SYSTEM :This is done by considering following points:1) BALANCING OF PHASE LOAD-

As a result of unequal loads on individual phase sequence,

components causes over heating of transformers, cables, conductors motors.

Thus, increasing losses and resulting in the motor

malfunctioning under unbalanced voltage conditions. Thus, keeping the system negative phase sequence voitage within limits, amount of savings

in capital (saving the duration of equipment )as well as energy losses. Thus, to avoid this losses, the loads are distributed evenly ‗as is practical‘ between the phases. 1) POWER FACTOR IMPROVEMENT-

Low power factor will lead to increased current and hence increase losses and will affect the voltage. The power factor at peak is almost unity. However, during off peak hours, mainly (11 am to 3 pm ) the power factor decreases to around 0.8, this may be due to following reasons,  Wide use of fans.  Wide industrial loads.

 Wide use of agricultural and domestic pumping motors.  Less use of high power factor loads like lightube etc. Now, to improve power factor at off peak hours the consumers must be aware of the effects of low power factor and must connect compensation equipment DSTACOM, capacitor bank.

[24]

SMART GRID GITA,BBSR

SMART METERS

A smart meter generally refers to a type of advanced meters that identifies

consumption in more detail than a conventional meter and communicates that information back to the local utility for monitoring and billing, a process known as telemetering.

These meters includes additional functions to power measurement such as communication, data storage, remote programming, and time-of-use rates, and are intended to be deployed as advanced metering infrastructure (AMI) solution. Smart meters are the next generation of electricity and gas meters. Smart meter

will empower customer to make choices on how much energy they use. Supplier will install two-way communication system that display accurate real time information on energy use in the home to the consumer and back to the energy supplier.

[25]

SMART GRID GITA,BBSR

COMPONENTS USED  ATMEGA 16

PIN DIAGRAM OF ATMEGA 16

[26]

SMART GRID GITA,BBSR

The ATmega16 is a low-power CMOS 8-bit microcontroller based on the AVR enhanced RISC architecture. By executing powerful instructions in a single clock cycle, the ATmega16 achieves throughputs approaching 1 MIPS per MHz allowing the system designed to optimize power consumption versus processing speed.

Pin Descriptions VCC Digital supply voltage. GND Ground. Port A (PA7..PA0) Port A also serves as an 8-bit bi-directional I/O port, if the A/D Converter is not used. Port pins can provide internal pull-up resistors (selected for each bit). The Port A output buffers have symmetrical drive characteristics with both high sink and source capability. When pins PA0 to PA7 are used as inputs and are externally pulled low, they will source current if the internal pull-up resistors are activated. The Port A pins are tri-stated when a reset condition becomes active,even if the clock is not running Port B

(PB7..PB0)

Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port B output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port B pins that are externally pulled low will source current if the pull-up resistors are activated. The Port B pins are tri-stated when a reset condition becomes active, even if the clock is not running. Port C (PC7..PC0) Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port C output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port C pins that are externally pulled low will source current if the pull-up resistors are activated. The Port C pins are tri-stated when a reset condition becomes active,even if the clock is not running. If the JTAG interface is enabled, the pull-up resistors on pins PC5 (TDI), PC3 (TMS) and PC2 (TCK) will be activated even if a reset occurs. [27]

SMART GRID GITA,BBSR

Port D

(PD7..PD0)

Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port D output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port D pins that are externally pulled low will source current if the pull-up resistors are activated. The Port D pins are tri-stated when a reset condition becomes active,even if the clock is not running. RESET

Reset Input.

A low level on this pin for longer than the minimum pulse length will generate a reset, even if the clock is not running. XTAL1 Input to the inverting Oscillator amplifier and input to the internal clock operating circuit. XTAL2 Output from the inverting Oscillator amplifier. AVCC AVCC is the supply voltage pin for Port A and the A/D Converter. It should be externally connected to VCC, even if the ADC is not used. If the ADC is used, it should be connected to VCC through a low-pass filter. AREF AREF is the analog reference pin for the A/D Converter

[28]

SMART GRID GITA,BBSR

 DTMF

The MT8870 is an 18-pin IC. It is used in telephones and a variety of other applications. When a proper output is not obtained in projects using this IC, engineers or technicians need to test this IC separately. A quick testing of this could save a lot of time in research labs and manufacturing industries of communication instruments. Here‘s a small and handy tester circuit for the DTMF IC. It can be assembled on a multipurpose PCB with an 18-pin IC base. One can also test the IC on a simple breadboard. For optimum working of telephone equipment, the DTMF receiver must be designed to recognize a valid tone pair greater than 40 ms in duration and to accept successive digit tone-pairs that are Greater than 40 ms apart. However, for other applications like remote controls and Radio communications, the tone duration may differ due to noise considerations. Therefore, by adding an extra resistor and steering diode the tone duration can beset to different values.

[29]

SMART GRID GITA,BBSR

The Status of LEDs on Pressing Keys

The circuit is configured in balanced line mode. To reject common-mode noise signals, a balanced differential amplifier input is used. The circuit also provides an excellent bridging interface across a properly terminated telephone line. Transient protection may be achieved by splitting the input resistors and inserting zener diodes (ZD1 and ZD2) to achieve voltage clamping. This allows the transient energy to be dissipated in the resistors and diodes, and limits the maximum voltage that may appear at the inputs. Whenever you press any key on your local telephone keypad, the delayed steering (Std) output of the IC goes high on receiving the tone pair, causing LED5 (connected )to pin 15 of IC via resistor R15) to glow. It will be high for a duration depending on the values of capacitor and resistors at pins 16 and 17. The MT8870D/MT8870D-1 is a complete DTMF receiver integrating both the band split filter and digital decoder functions. The filter section uses switched capacitor techniques for high and low group filters; the decoder uses digital counting techniques to detect and decode all 16 DTMF tone pairs into a 4-bit code. External component count is

[30]

SMART GRID GITA,BBSR

minimized by on chip provision of a differential input amplifier, clock oscillator and latched three-state bus interface.

[31]

SMART GRID GITA,BBSR

 LCD

[32]

SMART GRID GITA,BBSR

 IC 7805

The MC78XX/LM78XX/MC78XXA series of three terminal positive regulators are available in the TO-220/D-PAK package and with several fixed output voltages, making them useful in a wide range of applications. Each type employs internal current limiting, thermal shut down and safe operating area protection, making it essentially indestructible. If adequate heat sinking is provided, they can deliver over 1A output current. Although designed primarily as fixed voltage regulators, these devices can be used with external components to obtain adjustable voltages and currents.

[33]

SMART GRID GITA,BBSR

BLOCK DIAGRAM OF 7805

Electrical Characteristics (MC7805/LM7805)

[34]

SMART GRID GITA,BBSR

[35]

SMART GRID GITA,BBSR

 RELAY

[36]

SMART GRID GITA,BBSR

BLOCK DIAGRAM OF THE CIRCUIT

[37]

SMART GRID GITA,BBSR

Working Principle Smart grid does a lot of works. It is not possible to demonstrate each of the tasks in a single project. So an attempt is made to demonstrate some of its functions like automatic scheduling, power shading, distance controls etc. Description of loads: 1. Two simple houses representing a colony 2. A hospital 3. An industry

 In case of the colony, the houses are supplied by the main supply. In case of power cut, they are being supplied by the storage which is represented by an UPS. But when the storage discharges fully in case of long power cut, then the colony remains in dark.  In the hospital, since many of the biomedical equipment like breather are running continuously on the electricity, so there is an interruptible need of electric supply. So, for the hospital, an arrangement is made such that if the main supply goes off, then it is being supplied by UPS. When UPS discharges, then it is being supplied by another energy source representing renewable energy source.  In case of Industry, two loads are shown by means of two bulbs. The first load in the industry is its normal load and the second one is extra or overload. During normal operation, it is being supplied by the main supply. During power cut, it is being supplied by the renewable energy source.

[38]

SMART GRID GITA,BBSR

In case of overload, a notification is given to the colony or general consumers in form of a buzzer and then after sometime the power is cut in the colony for load shading purpose.

All these devices and operation are controllable by mobile showing the latest distance supervision and operation functions. This is done by means of DTMF (dual tone multiple frequency).

Fig: Smart Grid Here as can be seen, the main power supply is directly connected to the UPS and then to the colony loads. This makes the houses to work under main power cut conditions also by the use of UPS.

[39]

SMART GRID GITA,BBSR

Fig: UPS representing storage in the grid Here as can be seen, in the UPS, a dc storage is there in form of lead-acid battery followed by an inverter circuit and then by a transformer. Under normal condition when main supply is there, the battery get charged. 230v ac is stepped-down to approx.17v ac and is then rectified to 12v dc to charge the battery. In case of power cut, the storage acts as the source. 12v dc is converted to approx. 17v ac by the use of inverter circuit and then is stepped-up to 230v ac to supply to the loads.

[40]

SMART GRID GITA,BBSR

Fig: transformer with rectifier ckt. Fig: 2C relays As can be seen in the figure, in the first circuit, the supply from UPS is also stepped down to approx. 17v ac by means of a transformer and is then rectified to 12v ac to operate the 2C relay. The rectified output is given to the exciting coil of the 2c relay. Normally the plate is attached to the NC pin of the relay under not excited condition. So we have attached the NO (normally open) pin to the main supply, so that in case of main power on, the supply is provided by the main to the hospital. In case the mains gets off, the UPS supplies the hospital load. And if UPS too gets discharged in case of long power cut, then the renewable energy source connected to the NC (normally closed) pin comes into action and supplies the hospital load. [41]

SMART GRID GITA,BBSR

In case of industry too, the same concept is used. Ac supply from mains is stepped-down to be rectified to yield 12v dc to run the relay. In case the mains gets off, the renewable energy source supplies the industry load. Another complication has also been added to the industry to show the load shading. In case the extra or overload is on, a buzzer is made on by the help of microcontroller and then after some time the colony power cut happens. In addition to all these, all the loads can be controlled individually by using a mobile phone showing the distance operation using DTMF technology. For this purpose, a 1c relay each is connected to individuals loads. Also, the UPS charging or not charging can be controlled by distance operation using DTMF technology.

Fig: relays with loads.

[42]

SMART GRID GITA,BBSR

COMPARISION BETWEEN TODAY’S GRID AND SMART GRID (MODERN GRID) Characteristics 1) Self-heals

2) Motivates & includes the consumers 3) Resist attack

4) Provided power quality for 21st century needs

5) Accommodates all generation and storage option.

Today‘s grid

Smart grid

(Modern

grid) Respond to prevent further Automatically detects & damage. focus is on respond to actual & protection of assets emerging transmission following system faults. &distribution problems. Focus is on prevention. minimizes computer impacts. Consumers are uniformed Informed involve &active &non-participative with the consumers. Broad power system. penetration of demand response. Vulnerable to malicious Resilient to attach &natural acts of terrors natural disasters with rapid disasters. restoration capabilities. Focused on outstage rather Quality of power meets than power quality industry standards & problems. Solve response in consumers need. PQ issues revolving PQ issues. identified &revolved prior to manifestation. Various levels of PQ at various prices. Relatively small no. of Very large no. of diverse large generating plants. distributed generation & numerous obstacles exist storage devices deployed to for interconnecting DER. complements the large generating plant.

[43]

SMART GRID GITA,BBSR

Obstacles & Challenges In Europe and the US, significant impediments exist to the widespread adoption of smart grid technologies, including:       

Regulatory environments that don't reward utilities for operational efficiency, excluding U.S. awards. consumer concerns over privacy, social concerns over "fair" availability of electricity, social concerns over Enron style abuses of information leverage, Limited ability of utilities to rapidly transform their business and operational environment to take advantage of smart grid technologies. concerns over giving the government mechanisms to control the use of all power using activities, and Concerns on computer security.

Before a utility installs an advanced metering system, or any type of smart system, it must make a business case for the investment. Some components, like the power system stabilizers (PSS) installed on generators are very expensive, require complex integration in the grid's control system, are needed only during emergencies, but are only effective if other suppliers on the network have them. Without any incentive to install them, power suppliers don't. Most utilities find it difficult to justify installing a communications infrastructure for a single application (e.g. meter reading). Because of this, a utility must typically identify several applications that will use the same communications infrastructure – for example, reading a meter, monitoring power quality, remote connection and disconnection of customers, enabling demand response, etc. Ideally, the communications infrastructure will not only support near-term applications, but unanticipated applications that will arise in the future. Regulatory or legislative actions can also drive utilities to implement pieces of a smart grid puzzle. Each utility has a unique set of business, regulatory, and legislative drivers that guide its investments. This means that each utility will take a different path to creating their smart grid and that different utilities will create smart grids at different adoption rates. Some features of smart grids draw opposition from industries that currently are, or hope to provide similar services. An example is competition with cable and DSL Internet providers from broadband over power line internet access. Providers of SCADA control systems for grids have intentionally designed proprietary hardware, protocols and software so that they cannot inter-operate with other systems in order to tie its customers to the vendor.

[44]

SMART GRID GITA,BBSR

With the advent of cybercrime there is also concern on the security of the infrastructure, primarily that involving communications technology. Concerns chiefly center around the communications technology at the heart of the smart grid. Designed to allow real-time contact between utilities and meters in customers' homes and businesses, there is a very real risk that these capabilities could be exploited for criminal or even terrorist actions. One of the key capabilities of this connectivity is the ability to remotely switch off power supplies, enabling utilities to quickly and easily cease or modify supplies to customers who default on payment. This undoubtedly a massive boon for energy providers, but also raises some significant security issues. Cybercriminals have infiltrated the U.S. electric grid before on numerous occasions. Aside from computer infiltration, there are also concerns that computer malware like Stuxnet, which targeted systems on the SCADA software language widely used in industry, could do to a smart grid network

[45]

SMART GRID GITA,BBSR

PROS & CONS Advantages Of Smart Grid Reduces the cost of blackouts.  Helps measure and reduces energy conservation and costs.  Help businesses to reduce their carbon footprints.  Opens up new opportunities for tech companies meaning more jobs created. 

Disadvantages of Smart Grid  

Biggest concern: it has security and privacy. Two-way communication between power consumer and provider and sensors so it is costly.



Some type of meter can hacked.



HACKER-



Gain control of thousand even millions, of meters.



Increases or decreases the demand of power.



Not simply a single component .various technology components are used are software, system integrators, the power generators.

Future –  In the new future, will not be any vast development.  Risky because of financial developments and regulations.  In the long run, attitudes will change, wide spread usage of the smart grid from every business to every home just like the internet.

[46]

SMART GRID GITA,BBSR

Resources of information  Articles –  Energy Conservation Through Energy Management - by Prof. S. P. Rath (IEEMA magazine, January 2008)  WIRELESS Transmission Of Electric Power - by Syed Khadeerullah (Electrical India magazine, January 2008)  Magazine of “Electrical India 2010”

 Websites: www.nima.com  www.howstuffworks.com  www.wikipedia.com  www.xcelenergy.com/smartgridcity  www.schneider.com  www.powersmiths.com  www.renewableenrgyworld.com

[47]