Electric power systems constitute fundamental infrastructures in of modern society. Often continental in scale, electric power grids and distribution networks connect the generating stations to virtually every home, office, factory and institution across the country. Increased bulk power transactions and large scale integration of renewable energy sources are posing challenges to high-voltage transmission systems.
Environmental constraints and energy efficiency requirements also have significant effects on the design and operation of power transmission infrastructures. To address these challenges, power grids worldwide are undergoing a revolutionary transition to the so-called “Smart Grid”. Smart Grids are designed to imbibe intelligent processes and methodologies to the power grids to improve their flexibility, reliability and overall efficiency.
The electric power grid can be defined as a large system of high-tension cables that connects the power plants to consumers across a region. The grid is responsible for transmitting the generated power to the end-user. The electricity produced at power plants is usually “stepped up” to high voltages before it is transmitted through the grid. At a substation near the consumer, the power gets “stepped down” to voltage suitable for household and commercial use.
The beauty of the grid is that power can be bought and sold across vast expanses. Since the storage of electricity is very difficult, power grids support an optimal distribution of electricity allowing for a more balanced supply-and-demand equation. Also, minor transmission failures in one section of the grid can also be compensated for by using electricity available in another section of the grid.
Due to expanding demand, higher fuel costs and pollution-related issues, there has been a recent push to develop smarter electrical grids that are more efficient, cost effective and robust. The introduction of renewable energy systems such as wind, solar, biomass and geothermal generation facilities also entail the use of complex power management techniques in the grid. Since the power generated from the renewable power systems heavily depend on environmental factors, the power grids need to have sufficient “intelligence” to switch the transmission on/off based on the power generated.
The Smart Grid
The Smart Grid is achieved by incorporating digital technology to power grids to deliver electricity from power plants to consumers in a more intelligent, efficient, and transparent way. The basic concept of the Smart Grid is to add monitoring, analysis, control and communication capabilities to the power in order to maximise the throughput of the system while reducing the energy consumption. As all systems are automated and metered, they track when and how much electricity is used. By analysing and reporting all critical usage and health statistics, Smart Grids help system engineers to better manage loads and effectively cater to power demands.
Smart Grid Architecture
Smart Grid architecture relies on embedded technology to manage an energy system and automatically track usage. The conventional power grid management was carried out manually by disparate teams situated at each section of the grid, i.e. power plant, substation etc. The information available to these teams was mostly limited to their subsections alone and information about demand and outages were usually communicated through phone calls or fax messages.
In sharp contrast, Smart Grids allow for seamless transfer of information across the entire power grid. Embedded systems deployed at various points of the grid, from power generation to end-user consumption, help in analysing the critical characteristics of the system and also communicate it to other systems attached to the grid to achieve excellent energy management capabilities. Embedded systems are computers that can be integrated or “embedded” into a larger electrical or electronic equipment, to allow the equipment to have the necessary “intelligence” to function automatically. The use of embedded technology also allows the deployment of centralised Smart Energy Management Software to control the power available across the entire grid.
Interfacing with Electrical Appliances
Embedded systems are ubiquitous and are finding its use in almost all kinds of consumer and commercial equipment. Thus, a power delivery network built on embedded technology can far easily be interfaced with such equipment. This can ensure flow of electricity as well as information between the power plant and the equipment. The combined intelligence of the interconnected devices, coupled with automated control systems, can permit real-time power transactions and seamless interfaces among people, buildings, industrial plants, generation facilities and the electric network.
The information received from all the interconnected applications will enable the centralised energy management software to create an efficient power generation and transmission plan. An “intelligent” electric grid will also facilitate the proper delivery of electricity from renewable power systems such as wind, hydro and geothermal power plants that are often located at remote regions, far off from load centres. Additionally, interconnected systems will also enable faster detection of outages, correction of faults and quicker restoration of power supply. This will also improve the reliability of the grid and ensure security of the region as well.
The Smart Grid can be considered as a futuristic extension to the power grid and aims for better and efficient power management and consumption. Intelligent embedded power grids can create value up and down the chain – from efficient production of electricity in power plants to optimal supply and distribution of power to match the usage patterns of the end-users. The use of embedded technology would play a significant role in enhancing the “intelligence” of the existing power grids.