The establishment of a high-speed, two-way, real-time, integrated communication system is the basis for realizing the smart grid, without which none of the features of the smart grid can be realized, because the data acquisition, protection and control of the smart grid need the support of such a communication system, and thus the establishment of such a communication system is the first step towards the smart grid. At the same time, the communication system has to penetrate into thousands of households as well as the power grid, thus forming two closely connected networks - the power grid and the communication network - and only in this way can the goals and main features of the smart grid be realized. The following figure shows the relationship between the power grid and the communication network. High-speed, bi-directional, real-time, integrated communication systems make the Smart Grid a dynamic, large-scale infrastructure for real-time information and power exchange interaction. When such a communications system is in place, it increases the value of the grid by improving the reliability of its power supply and the utilization of its assets, thriving the power market, and defending the grid from attacks.
With the completion of a high-speed, two-way communication system, the smart grid realizes its most important feature, the self-healing feature, by applying advanced information technology through continuous self-monitoring and correction. It also monitors various disturbances, compensates for them, and redistributes tidal currents to avoid the expansion of accidents. High-speed bi-directional communication systems enable a variety of different Intelligent Electronic Devices (IEDs), smart meters, control centers, power electronic controllers, protection systems, and users to communicate in a networked fashion, improving the ability to harness the grid and the level of quality service. In this technology area, there are two main aspects of technology that need to be focused on, one is the open communication architecture, which forms a "plug-and-play" environment that enables networked communication between power grid components; the other is the unified technology standard, which enables seamless communication between all sensors, intelligent electronic devices (IEDs) and application systems, and the other is the unified technology standard, which enables seamless communication between all sensors, IEDs and application systems. The second is a unified technical standard that enables seamless communication between all sensors, intelligent electronic devices (IEDs), and applications, i.e., information is fully understood between all these devices and systems, and interoperability is realized between devices, between devices and systems, and between systems. This requires the cooperation of power companies, equipment manufacturers, and standard-setting organizations in order to realize the interoperability of communication systems. Parametric measurement technologies are essential components of the Smart Grid. Advanced parametric measurement technologies acquire data and convert it into data information for use in all aspects of the Smart Grid. They assess the health of grid equipment and the integrity of the grid, perform meter readings, eliminate electricity bill estimates and prevent electricity theft, mitigate grid congestion, and communicate with customers.
The smart grid of the future will eliminate all electromagnetic meters and their reading systems, replacing them with smart, solid-state meters that enable two-way communication between utilities and customers. The microprocessor-based smart meters will have more functions, in addition to measuring the use of electricity at different times of the day and the cost of electricity, as well as storing the peak power price signals and rates issued by the utility and notifying the user of what rate policy to implement. More advanced features include the ability for users to compile their own schedules based on the rate policy and to automatically control the strategy of power usage within the user.
For utilities, parametric measurement technology gives power system operators and planners more data support, including data on power factor, power quality, phase relationships (WAMS), equipment health and capacity, meter damage, fault location, transformer and line loads, temperatures of critical components, outage confirmation, power consumption and forecasting. The new software system will collect, store, analyze and process this data for use in other utility operations.
The digital protection of the future will be embedded in computer agent programs that will dramatically improve reliability. A computer agent program is an autonomous and interactive adaptive software module. Wide-area monitoring systems, protection and control schemes will integrate digital protection, advanced communications technologies, and computer agent programs. In such an integrated and distributed protection system, the protection elements will be able to adaptively communicate with each other, and this flexibility and adaptability will greatly improve reliability, because even if part of the system fails, other protection elements with computer agents will still be able to protect the system. Smart grids will require extensive use of advanced equipment technologies to greatly improve the performance of transmission and distribution systems. The equipment in the future smart grid will fully utilize the latest research results in materials, superconductivity, energy storage, power electronics and microelectronics technologies to improve power density, power supply reliability and power quality as well as the efficiency of power production.
The smart grid of the future will utilize advanced technologies in three main areas: power electronics, superconductivity and high-capacity energy storage. Power quality will be improved through the adoption of new technologies and the search for an optimal balance between grid and load characteristics. Grid transmission capacity and reliability will be improved by applying and retrofitting a wide range of advanced equipment, such as equipment based on power electronics and new conductor technologies. Many new energy storage devices and power sources are to be introduced into the distribution system, while new network structures, such as microgrids, are to be utilized.
Economic FACTS devices will utilize low-cost power semiconductor devices that are more controllable than existing semiconductor devices, allowing these advanced devices to be widely deployed. Distributed generation will be widely used, with multiple units connected through communication systems to form a dispatchable virtual power plant. Superconductor technology will be used in short-circuit current limiters, energy storage, low-loss rotating equipment, and low-loss cables. Advanced metering and communication technologies will enable demand response applications. Advanced control technologies are devices and algorithms in the Smart Grid that analyze, diagnose, and predict status and identify and take appropriate measures to eliminate, mitigate, and prevent supply interruptions and power quality disturbances. These technologies will provide control methods on the transmission, distribution and customer side and can manage active and reactive power throughout the grid. In a way, advanced control technologies are closely dependent on and serve the other four key technology areas, such as advanced control technologies to monitor the basic components (parametric measurement technologies), provide timely and appropriate responses (integrated communication technologies; advanced device technologies) and provide rapid diagnosis of any event (advanced decision technologies). In addition, advanced control technology supports market quotation techniques and improves asset management.
In the future, the analytical and diagnostic functions of advanced control technology will introduce pre-programmed expert systems, which will take automatic control actions within the limits allowed by the expert system. The actions performed in this way will be at the second level, and this self-healing grid characteristic will greatly improve the reliability of the grid. Of course advanced control technology requires an integrated high-speed communication system and corresponding communication standards to handle large amounts of data. Advanced control technology will support distributed intelligent agent software, analysis tools, and other applications.
(1) Collecting data and monitoring grid components
Advanced control technology will use smart sensors, smart electronic devices and other analytical tools to measure system and user parameters and the status of grid components to assess the status of the entire system, which is quasi-real-time data that is important for grasping the overall operation of the grid, and to utilize vector measurement units and global positioning systems (GPS). vector measurement unit and the time signals of the global positioning satellite system to realize the early warning of the power grid.
(2) Analyzing data
Quasi-real-time data as well as powerful computer processing capabilities provide rapid expansion and advancement of software analysis tools. Condition estimation and contingency analysis will be done at the second rather than the minute level, giving advanced control techniques and system operators enough time to respond to urgent problems; expert systems will transform data into information for rapid decision making; load forecasting will apply this quasi-real-time data, along with improved weather forecasting techniques, to accurately predict loads; and probabilistic risk analyses will be routinely performed to determine what happens to the grid during equipment maintenance, during periods of high system stress, and during periods of inactivity. during equipment maintenance, during periods of high system stress, and during undesired power interruptions; and grid modeling and simulation allows operators to recognize accurate possible scenarios for the grid.
(3) Diagnostics and Problem Solving
Quasi-real-time data processed by high-speed computers allow expert diagnostics to identify solutions to existing, developing, and potential problems and present them to system operators for judgment.
(4) Performing Automatic Control Actions
Smart grids make it possible to perform automatic control actions for problem detection and response through a combination of real-time communication systems and advanced analytics, which can also reduce the expansion of existing problems, prevent the occurrence of urgent problems, and modify system settings, states, and currents to prevent the occurrence of predicted problems.
(5) Providing Information and Options for Operators
Advanced control technology not only signals actions to control devices, but also provides information to operators. The control system collects a large amount of data is not only useful to itself, but also to the system operator has a great value of application, and these data to assist the operator to make decisions. The million-volt-class ultra-high-voltage AC project, the Yellow River Grand Span Project, has begun intense wiring.
Decision-support technology transforms complex power system data into comprehensible information that system operators can see at a glance, so animation technology, dynamic coloring technology, virtual reality technology, and other data presentation techniques are used to help system operators recognize, analyze, and deal with urgent problems.
In many cases, the time it takes for system operators to make decisions is reduced from hours to minutes to seconds, so the smart grid needs a broad, seamless, real-time set of applications, tools, and training to enable grid operators and managers to make decisions quickly.
(1) Visualization-decision support technology takes large amounts of data and crops it into formatted, time-period, and technology-by-technology breakdowns of the most critical data for grid operators, and visualization technology displays this data in a visual format that operators can quickly grasp for analysis and decision-making.
(2) Decision Support - Decision support technology identifies existing, evolving, and projected problems, provides decision support analysis, and presents the various scenarios, multiple options, and the likelihood of success and failure of each option needed by the system operator.
(3) Dispatcher Training - Utilizing decision-support technology tools and dynamic simulators with industry-certified software will significantly improve the skills and proficiency of system dispatchers.
(4) User Decision Making - Demand Response (DR) systems provide users with information in a very easy to understand manner, enabling them to decide how and when to buy, store or produce electricity.
(5) Improved Operational Efficiency - When decision-support technologies are integrated with existing asset management processes, managers and users are able to improve the efficiency and effectiveness of grid operations, maintenance, and planning.