Source: China Enterprise News Author: Yu YixinFor us, the current intelligence of the power grid is actually the second intelligence. The first intelligentization occurred from 1970 to the beginning of 1980, during which power grid blackouts occurred frequently, represented by the New York blackout. Therefore, the US government required power companies to use computers at that time. Therefore, 2TU was installed on the ultra-high voltage transmission lines of large power plants in the power system, and some data was sent to the dispatch center, The dispatch center has developed an energy management system for safety analysis and optimization of the power grid. At that time, there was no development towards the distribution network, that is, the power grid below 110 kV. Nowadays, a large number of power grids in cities are not intelligent, because the prices of communication technology, information technology, and some power electronic technologies at that time were too expensive to afford.The current situation has changed because communication and information technologies are too cheap. It is very cost-effective for us to do this now, so this time we will focus on the first shortage, which is the distribution of electricity. Of course, there is still room for further improvement in the fields of power generation and transmission.The driving force behind the entire intelligent power grid this time is market factors, safety factors, and environmental factors, among which environmental factors are particularly prominent because it is time to limit the emission of carbon dioxide in the atmosphere, especially in China. The issue of air pollution makes us feel that this problem is very urgent, so the driving force for this time is much greater than for the first time.First, let's take a look at renewable wind and solar power generation. Our country's wind and solar energy resources are extremely abundant, and the price advantage is becoming increasingly evident. We don't have any energy crisis issues at all. The solar energy resources on this Earth are one hundred times that of wind energy, and the wind energy resources are one hundred times that of water energy.There are resources, but the problem is how to cover them. You can use roofs, roads, fish ponds, farmland, etc., as well as deserts and mudflat. In fact, 76% of China's land area can be equipped with wind turbines, and 100% of its land can be equipped with solar energy, which is a very good condition for China. Everyone knows that Germany has a good utilization of solar energy, and our resources are much better than Germany's.Let's take a look at the photovoltaic system again. The prices of photovoltaic and wind power have gradually decreased in recent years, especially in the period from 1987 to 2013, when they dropped to the original 1%, and now they are still declining at an annual rate of 15%. Considering the overall social costs, including investment, operating costs, fuel costs, reliability costs, environmental costs, network losses, etc., if electricity is generated from 2000 kilometers away from the northwest region, such as wind energy, and sent to the eastern region, the total cost per kilowatt hour is approximately over 90 cents. If developed and utilized on-site, it would cost around 60 cents now. So now it seems more cost-effective to develop and use on site.But what are the issues with using it? Wind and solar energy are intermittent, fluctuating, and uncertain, which makes their use more difficult. Therefore, some measures are needed for the power system to have some smoothing measures. These smoothing measures include the adjustable energy of large thermal power generation units, including energy storage, user demand coordination, and other factors. But to make good use of these factors, we need the power grid, which is the smart grid.The overall idea of a smart grid is to utilize new technologies such as new energy and the internet to achieve the intelligence of the grid. What is the result to be obtained? It is to change people's way of life and work like the internet. Currently, we are actually a relatively intelligent power grid. The more intelligent power grid we are building now refers to the power grid that can be achieved using existing good technologies or technologies that may be available in the next few years.There is currently no clear definition of a smart grid. The characteristic of a smart grid is the bidirectional flow of electricity and information, in order to establish a highly automated and widely distributed energy exchange network. In order to exchange information in real-time and achieve almost instantaneous supply-demand balance at the device level, the advantages of distributed computing and communication are introduced into the grid. Two sentences: A smart grid is a power grid, and a communication network. These two networks are integrated from the basic electrical equipment, with the aim of building a highly automated and widely distributed energy network. When we started building smart grids, everyone recognized automation, but we were too slow to recognize widespread distribution, which actually caused significant economic losses to our country.The second sentence is to achieve real-time exchange of information and achieve almost instantaneous supply and demand balance at the device level, which are two more things. Information sharing is the core content of a smart grid, with power balance. The power of the grid must be almost balanced between supply and demand on time, otherwise the grid cannot operate safely. Now that users can cooperate with the grid, our load and power generation can be controlled, which is an important feature of the smart grid.What engineering issues do smart grids include? One is wide-area monitoring and control. In the past, the power grid measured data at every point within a large range, hundreds or thousands of kilometers, and when it was sent to the dispatch center, it was different due to experiments. Now that satellite positioning is available, it can be achieved through GDS or Beidou satellites, and the data sent can be labeled, which is a significant change. It should be said that our country's wide area measurement system is a globally built system, but there is still a lot of work to develop its potential.The second is the integration of communication and information technology. The third is the integration of distributed renewable energy generation. The fourth is the expansion of the transmission system. The fifth is the management of the distribution network.There are two common terms in intelligent distribution networks: microgrid and active distribution network.The traditional power grid has no power supply at the distribution level, and is distributed like a tree from the large power grid. Now that there is power supply at the end of this tree, the traditional power grid cannot adapt. Therefore, it needs to be able to adapt to these distributed power sources in the distribution network. The power grid that can measure and control distributed power sources is called the active distribution network.There is a term commonly heard in intelligent distribution networks called microgrids.A microgrid is a part of the distribution network, which includes both power generation and loads, including important and controllable loads. The entire area is relatively independent from the power grid company, so it is particularly suitable for a single enterprise or community to achieve.In the future, microgrids will be very common. Currently, due to their ability to smoothly distribute the volatility of wind and solar energy, the investment is relatively high. Therefore, the focus is on using microgrids in areas with high reliability requirements, such as military departments or hospitals, desert areas, remote areas, or islands. In the future, it will expand significantly.In terms of user demand coordination, in order to achieve demand response, it is necessary to establish a communication system. What we need to complete now is to use user electricity meters to drive the improvement of a one kilometer communication line at the end of the entire power grid, because the communication line above has already been built very well. This improvement is not only beneficial for the power grid, but also provides an opportunity for the development of smart cities.The data provided by smart meters currently accounts for about 40% of the entire electricity big data, and this part of the data has many uses that need to be developed. China's smart meters have already installed 400 million pieces, which may be much higher than the combined smart meters of all countries around the world. But the current problem is that our communication system cannot quickly send all the data, and the communication system needs to be further improved and improved. Another aspect that needs to be noted is to achieve real-time sharing of data. Currently, the islanding of data is quite prominent, and some data even stays in the hands of some teams, which cannot be shared by others. In this way, the entire big data cannot play its due role. Therefore, reform should be carried out and the market should be opened, which are two issues that need to be paid attention to in the development of any new technology.What are the benefits of a smart grid? According to two estimates by the American Academy of Electrical Engineering, the direct benefits of improving reliability, improving economy, and reducing network losses are approximately four times that of investment.It should also be noted that the smart grid is actually an enabler and a promoter. We say that the Internet is "Internet plus", and the smart grid is also "smart grid+". After the implementation of the smart grid, because of the wide range of technologies, it can provide new energy technologies, communication technologies, software technologies, automation technologies, and energy storage technologies, including electric vehicles, advanced sensor technologies, power electronics technologies There are huge business opportunities in areas such as smart appliances, and this market is very large.According to Cisco's estimation, the benefits of a smart grid may be 50 times that of the Internet, but later on, the Internet of Things (IoT) emerged, and the smart grid became a typical component of IoT. In this way, everyone knows that the Internet of Things is a disruptive technology in the 21st century. What is one important meaning of being disruptive? Its market scope is too large, so the market provided by smart grids in the future as a typical Internet of Things is very large. Our country must seize this opportunity.
