The future of power sector is linked with smart grid systems that would integrate energy infrastructure, processes, devices, information and markets into a coordinated and collaborative process that allows energy to be generated, distributed and consumed more effectively and efficiently, writes Rai Umraopati Ray.
On 31 July, the northern grid collapsed, and on 1 August, in a wider blackout, the northern and eastern ones also went down, leaving nearly 620 million people without electricity. Trains, metros, traffic lights, and many essential services were halted which caused chaos everywhere. The New York Times reported, “For a country considered a rising economic power, Blackout Tuesday—which came only a day after another major power failure—was an embarrassing reminder of the intractable problems still plaguing India: inadequate infrastructure, a crippling power shortage and, many critics say, a yawning absence of governmental action and leadership.â€
A panel investigating the matter reported that Uttar Pradesh, Punjab and Haryana drew more than their allotted share of electricity that led to India’s worst power outage. The situation was worsened by low consumption in western India, technical mistakes and maintenance shutdowns. “The cause of the failure can’t be exactly pinpointed. It was caused due to multiple issues. Many of the transmission links in the northern region were out due to maintenance work and annual planned shutdown as it happens during the monsoon season,†said a power ministry official aware of the report’s finding, requesting anonymity.
Experts say had there been a smart grid, this crisis could have been easily been avoided. A smart grid would have shared the data in real-time which would have helped to instantaneously identify the fault. Smart grid would have also initiated self-healing and would have cordoned the fault line and restricted the impact of the failure. In a real-time response, it would have also identified the states overdrawing power. According to the panel’s findings, the under frequency relays (UFRs) didn’t work as “their settings were not done at proper valuesâ€. UFRs disconnect power supply if the frequency falls below a set range.
“The fault is with the states as the UFRs are with the electricity distribution companies. It is the responÂsibility of the regional load despatch centres (RLDCs) to verify the settings at frequent intervals. On the second day, all of the above happened with no commiÂserate load reduction,†another ministry official said.
The report has suggested new planning criteria and fresh transmission capacity besides recommending that UFR settings be checked more frequently. It has also asked for special protection schemes and defence mechanisms such as islanding. This would isolate the fallout of a grid disturbance on the national power grid, restricting it to a particular region, or allow a particular region or essential service to isolate itself if there is a grid failure. It also recommended scrapping the unscheÂduled interchange (UI) mechanism.
The grid code
Not long ago, the power ministry had written to the states to put in place a defence mechanism and adhere strictly to the Indian Electricity Grid Code. The Ministry is also looking at changes to be made to the Grid Code for proper implementation. The Special Protection Schemes help prevent grid failure situations. These are to be implemented at state electricity distribution centres. This system disconnects the circuit autoÂmatically during critical situation. This means if any customer is drawing more electricity than what is allotted or frequency of the transmission line drops from normal, the circuit gets disconnected automatically. A shortfall in supply due to inadequate power infrastructure requires some lead time, as investments in power sector are capital- and time-intensive. Timely planning and development of transmission and distribution (T&D) lines to deliver power to the load centres is equally important. Overall, matching of demand and supply and strengthening the transmission network will be needed for long-term solution for grid stability.
Many experts believe that the economic growth of a developing nation like India depends heavily on reliÂability and quality of its electric power supply. Generally, rigorous planning is done for the addition of new geneÂration and the expansion of existing transmission netÂworks. However, distribution systems have grown in an unplanned manner resulting in high technical and comÂmercial losses in addition to ending up delivering poor quality of power. Efficient operation and maintenance of distribution systems is hampered by non-availability of system topological information, historical data and real-time health information of distribution system compoÂnents such as transformers and feeders. Supplementary reasons include the lack of efficient tools for operational planning, and advanced methodologies for quick fault detection, isolation, and service restoration, etc.
All these factors have eventually led to increased system losses, poor quality and reliability of power supply apart from witnessing increased peak demand and poor return of revenue. Hence, the increased reliance on Distribution Automation (DA) and its subsidiaries to mitigate the existing bottlenecks. Across the world, DA has been acknowledged as being indispensable in overÂcoming the consequences arising out of this shortfall.
Loss reduction programme
In India, city electricity distribution autoÂmation (CEDAS) was the first initiative towards power system automation systems under R-APDRP. The focus of the programme was on actual, demonstrable perforÂmance in terms of loss reduction through adoption of information technology and strengthening and up-gradation of sub-transmission and distribution networks. Both state and private owned discoms have embarked on a progressive approach in bringing about CEDAS. These projects were started to initiate the DA programme in India. The DRUM project in Aurangabad and electric distriÂbution companies such as NDPL, BESCOM, REL and DHBVNL have taken a lead in this direction.
As VSK Murthy Balijepalli, Department of Electrical Engineering, Indian Institute of Technology Bombay, and others in their paper, “Towards Indian Smart Gridsâ€, writes, a Smart Grid integrates innovative tools and technologies from generation, transmission and distriÂbution all the way to consumer appliances and equipÂment. This concept, or vision, integrates energy infraÂstructure, processes, devices, information and markets into a coordinated and collaborative process that allows energy to be generated, distributed and consumed more effectively and efficiently. The depÂloyment strategy for intelligent smart grid encapsulates all stages of the eleÂctric power lifecycle (generation, transmission, distriÂbution, metering, and customer).
Digital energy system
A modernised/smart grid would create a digital energy system that will detect and address emerging proÂblems on the system before they affect service; respond to local and system-wide inputs and have much more information about broader system problems; incorporate extensive measurements, rapid communiÂcations, centraÂlised advanced diagnostics, and feedback control that quiÂckly return the system to a stable state after interruÂptions or disturbances.
“Smart grids are sophisticated, digitally enhanced power systems where the use of modern communications and control technologies allows much greater robustness, efficiency and flexibility than today’s power systems. A smart grid impacts all the components of a power system. However, much of the smart grid focus in a power system is at the distribution level. One subset of smart grids is smart metering/advanced metering infrastructure (AMI) etc. In a smart grid, all the various nodes need to interÂconnect to share data as and where needed. Power utiÂlities around the world are adopting smart grid techÂnologies to make the power infrastructure robust, self healing, adaptive, interactive and cost-effective. Indian power sector has also the opportunity to leap-frog given our limited legacy systems and the anticipated growth in power sector and infrastructure. In view of the antiÂcipated growth in Indian power sector and infraÂÂstructure, there is huge potential for adopting Smart Grid TechÂnologies and designs in big wayâ€, explains Devendra Singh, Joint Secretary, Ministry of Power. According to Dr Sam Pitroda who is also the Chairman of the India Smart Grid Taskforce, smart grids will ensure power availability and reliability, and help idenÂtify faults in power supply, for rapid redressal.
Similarly, it has been observed that interoperability among various systems of the power grid is crucial for achieving the benefits of open architecture-based future control centres. Smart grid implementations will depend on the accurate and timely flow of information among systems of all kinds in a highly-scalable system of systems architecture. Dynamic prices and demand response signals should flow from utilities and aggregators to customers. Meter data needs to flow to utilities and customers. Market transactions should flow from custoÂmers to markets to operators and back. Values, status and control information should flow from devices produced by different companies and embedded throughÂout the grid to operators and customers. It should enable different vendors to develop systems that work together and interoperate effectively as integrated solutions.
When considering interoperability around conneÂctivity, one needs to consider at least three, if not more, aspects of interoperability. Whether it is physical conneÂctivity, data exchanges, architectural models and possibly process and governance impacts, complete underÂstanding of interoperability is of utmost imporÂtance. Therefore, smart grid interoperability spans a very diverse collection of connectivity persÂpectives. Experts say that we must consider no less than “consumer-to-gridâ€, “utility-to-grid†and “generation-to-gridâ€. “There is no doubt smart grid will help to develop good outage manaÂgeÂment and customer relationship manageÂment to improve the consumer relationâ€, says Ajay I Kumar, Vice President, BSES Rajdhani Power Ltd, Delhi.
The future of power sector is linked with the implemeÂntation of the smart grid systems with effective interÂoperability, which help customer to get un-interrupted power supply at lower tariff. Newer technologies will operate the grid efficiently, optimise energy usage, manage groÂwing energy demand and also help in improÂving the environmental quality.
Boosting investor confidence
Smart grid technology would’ve minimised human factors and thus could’ve saved the grid collapse. Smart grid works on certain algorithms and logics. Whenever a situation arises, the grid would automatically follow a predefined process which would be a welcome change to a conventional grid supervision where chances of human error, negligence or incompetency may creep in.
Wherever smart grids have been introduced, it has led to reliÂability of network and superior quality of supply. It has not only helped to avert disasters but also improve the response time for any outages. Troubleshooting has been easier. It also proÂvides flexibility to integrate renewables and energy other forms of energy.
The biggest problem a conventional power grid faces is that it involves too many human factors hence it is susceptible to failure(s). The grid has to be reliable 365 days, 24×7. Smarter the grid, the better it is for the network and reliable, quality supply. Smart grids are an effective way of managing the system. Needless to say, it would boost investor confidence.
-Ramesh Narayanan, CEO, BYPL
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