Future grid green energy sample
Visit the world's first county-level 100% new energy new power system technology demonstration project
Our reporter Wang Zhen
At present, we are no strangers to wind power generation and solar photovoltaic power generation.
However, due to the randomness and volatility of wind and light resources, under normal circumstances, they need to be integrated into the large power grid for centralized power supply together with other power sources such as hydropower and thermal power.
However, in Guangshui City, Hubei Province, which is known as the "Gateway to Northern Hubei", a new power system powered by 100% wind and solar energy has already taken shape.
A month ago, this new type of power system has started the power transmission program.
Soon, more than 200,000 people in the local power supply area will be able to independently generate electricity with 100% wind and solar energy.
There is no precedent for such a county-scale real power system with 100% wind and light as the power source.
After the project is fully completed, it will become the world's first demonstration project that can operate independently for a long time and can achieve 100% independent power supply from new energy.
What is the significance of building a 100% new energy new power system?
What are the characteristics of this new type of power system, and what technological breakthroughs have been achieved?
The reporter recently interviewed the comrades in charge of the project, and took you to visit the world's first county-level 100% new energy new power system technology demonstration project.
1 It is not only a practical real power grid, but also a test platform with the characteristics of the future power grid
Realize local consumption and balance of wind and light resources
Baolinsi Village, Shili Street, Guangshui City, Hubei Province.
On the sunny slopes of more than a dozen hills, there are solar photovoltaic power plants covering an area of more than 700 mu, with more than one million photovoltaic panels shining brightly in the sun.
About 20 kilometers away, on the hills near Yaodian Village, Lidian Town, Guangshui, there are more than ten wind turbines, with 70-meter-long blades whirling.
This is Baolin wind-solar integrated power station and one of the important power sources of the world's first county-level 100% new energy new power system technology demonstration project.
According to reports, the Guangshui 100% new energy new power system technology demonstration project is one of the "Ten Demonstration Projects" of the State Grid built around the construction of a new power system and serving the "double carbon" goal. It started power transmission on November 19. program.
The total installed capacity of new energy is 244 MW, including 3 wind farms in Yingzizhai, Niujishan, and Lianhua Village, and Baolin Scenery Integrated Power Station, including 194 MW of wind power installed capacity and 50 MW of photovoltaic installed capacity.
The power supply area is 418 square kilometers, covering the main commercial, industrial and residential users in Guangshui City, with a population of more than 200,000 and a maximum load of 61 MW.
"Guangshui's 100% new energy new power system is a new form of power grid with new energy power supply as the main body, flexible interconnection with the large power grid, collaborative interaction between source, network, load and storage, and a future-oriented power grid." Deputy Vice President of Science and Technology Innovation Department of State Grid Hubei Electric Power Co., Ltd. Director Wang Wei told reporters.
To put it simply, it first uses 100% wind power and photovoltaic new energy as the power supply; secondly, it can operate independently, using the local wind and light resources of Guangshui to supply power for Guangshui, and can also be interconnected with the large power grid. When the local power generation is sufficient, the excess power is sent to the large power grid, and when the local power generation is not enough, the power is taken from the large power grid; thirdly, the power side, grid side, load side and energy storage side can realize flexible interaction, even When new energy power generation fluctuates violently, it can respond quickly to ensure the safety and stability of the power grid.
It can be said that it is not only a practical and realistic power grid that can ensure that wind and light new energy generation can be generated and used, but also an open test platform with the characteristics of future power grids.
And that's exactly what building this new power system is all about.
Achieving carbon neutrality is a broad and profound economic and social systemic change.
According to reports, with the in-depth advancement of the "double carbon" process, the energy supply structure will be adjusted in depth.
Industry insiders predict that by 2030, the installed capacity of wind power, solar power and other new energy power generation in my country will surpass coal power and become the largest power source.
However, due to the inability to store a large amount of electric energy, wind and photovoltaic power generation is facing the problem of consumption.
Take Suizhou City, where Guangshui is located, as an example. Thanks to its geographical advantages, its wind and light resources are very rich. The existing installed capacity of new energy is 2.7 times that of the local maximum load.
"Usually, there are two ways to consume wind power and photovoltaics. One is local consumption, and the other is delivery." Wang Wei introduced that in the future, with the further acceleration of the development of new energy in various places, those that cannot be consumed locally The space for new energy delivery will also be gradually compressed, and the problem of consumption will also intensify.
At the same time, due to the randomness and volatility of wind and photovoltaic power generation, their output is not as stable as that of thermal power and hydropower. If a high proportion of wind power is used in the existing power grid, it will bring unprecedented challenges to the safe and stable operation of the power grid.
"If the electricity generated by wind and new energy cannot be used, then power generation is meaningless." Wang Wei said that under this background, State Grid Hubei Electric Power Co., Ltd. carried out the Guangshui 100% new energy new power system technology demonstration project. Committed to solving the problem of new energy consumption, researching key technologies of new power systems, and forming a new form of future power grid that is "mainly local balance, supplemented by interaction with the main grid".
China Power Construction Group Hubei Engineering Co., Ltd. is responsible for the project design.
"The research direction was determined at the beginning of 2020, and the project was officially established in November 2020. Eight core technologies and key equipment, including self-synchronizing voltage sources and high-voltage and large-capacity energy routers, were successfully developed. The local consumption and balance of resources is also a "test field" for building the future power grid." said Chen Xiaoming, director of the Science and Technology Division of the Science and Technology Innovation Department of State Grid Hubei Electric Power Co., Ltd.
2 Flexible interaction of source, network, load and storage
Improve the level of flexible interconnection of regional power grids
During the interview, when talking about Guangshui’s 100% new energy new power system, Liu Ju, who is in charge of the Science and Technology Department of the Science and Technology Innovation Department of State Grid Hubei Electric Power Co., Ltd., said the word "flexible" the most.
According to reports, Guangshui's 100% new energy new power system is an independent power grid system that can operate completely independently.
However, it is not completely "one difference and two wide" between it and the large power grid, but can achieve flexible and flexible interaction.
"The power generation output of the traditional power system is controllable, the load changes relatively regularly, and the balance of power and electricity is relatively easy. However, due to the wind and light, the 100% new energy new power system of Guangshui has more uncertainties. Once extreme In the event of an accident, the large power grid can guarantee it.” Liu Ju told reporters that the connection between the regional power grid of the demonstration project and the large power grid is inseparable from a key device—the energy router.
Just like the WiFi network router used in our home, when the energy router is turned on, the regional power grid of the demonstration project will "join hands" with the large power grid; when it is turned off, it will "break up" with the large power grid.
"The energy router is like a valve." Liu Ju said. It is worth noting that, unlike the traditional power system, which flows from the power source side to the load side through power transmission, transformation, and distribution, the voltage level is from high to low and the flow is unidirectional. With the help of energy routers, the regional power grid of the demonstration project can not only take power from the large power grid, but also reversely send power to the large power grid when there is a surplus of local wind power and photovoltaics, so as to realize flexible interconnection with the large power grid.
Ye Chang, who is in charge of the New Power System Research Center of the State Grid Hubei Electric Power Research Institute, introduced that the function of the energy router is not limited to this. It has 7 ports, each of which can be independently controlled and operated, and can be connected to the large power grid or local Distributed wind and photovoltaic power sources can also be connected to the load end and energy storage end to realize the flexible interaction of source, grid, load, and storage, and the flexible networking of multi-voltage level supply areas.
It is understood that in a new power system with a high proportion of new energy, there are usually a large number of photoelectric and wind power connections between different voltage levels, and electric vehicles and energy storage are widely distributed. Wait for a new request.
"As my country's first multi-port high-voltage and large-capacity energy router, it can be used to explore the networking mode and key interconnection equipment of new power systems." Liu Ju told reporters.
Recently, the system commissioning personnel of Hubei Electric Power Research Institute completed the energy storage charge and discharge power and duration test after the power transmission of Guangshui 100% new energy new power system, which verified the reliability of related functions.
Energy storage is an essential part of building a new power system.
It is understood that the maximum daily fluctuation amplitude of the load in the demonstration area is 38MW, with a fluctuation rate of 76%; the maximum daily fluctuation amplitude of wind and photovoltaic power generation output is 139MW, with a fluctuation rate of 86%.
This requires energy storage to stabilize the fluctuation of new energy output and ensure the safety and stability of power supply.
"The demonstration project has built a total of 9 energy storage power stations on the grid side, power source side, and load side, so as to achieve stable support for the grid and dynamic balance of source and load, and can effectively increase the wind and light resource consumption capacity by 15% to 20%. .” Liu Ju introduced that six of them were built on the load side.
"That is to say, the user end may also be transformed into a power supply." Ye Chang further explained that one of the six energy storage power stations is built in the factory area of a large user, and the other five are located at electric vehicle charging stations.
In the Shili Industrial Park of Guangshui City, there is the Sanfeng Turbine Energy Storage Power Station.
"This is equivalent to a micro-grid, which can not only generate photovoltaic power for the factory's own use, but also store the surplus electric energy and discharge it when the power consumption peaks in the demonstration area and the output of new energy is insufficient." Liu Ju said, if the energy storage The power station is charged during the low power period at night and the flat period in the afternoon, and discharged during the peak period and peak period. It is estimated that the electricity bill can be saved by nearly 30,000 yuan per month.
Spontaneous self-use, surplus storage, Internet access.
Like the Sanfeng Turbine Energy Storage Power Station, the five distributed solar-storage-charging integrated smart electric vehicle power stations are also a micro-grid consisting of photovoltaics, energy storage and charging piles.
"An electric car is an energy storage device."
According to reports, in the future grid, more distributed energy storage will emerge, and more electric vehicle owners and more families will participate in the interaction with the grid.
3 Develop a collaborative control system based on cloud computing and artificial intelligence
Realize real-time optimal operation of power grid
Click the mouse to open the real-time cooperative control system of Hubei Guangshui Source Network, load and storage, and enter the power monitoring interface... In the ground dispatching machine room of Suizhou Power Supply Company of State Grid Hubei Electric Power Co., Ltd., Liu Dan and Hu Pan, the system commissioning directors of Hubei Electric Power Research Institute, Four new energy power stations, including Baolin wind-solar integrated power station and Yingzizhai wind farm, are being tested for flexible power adjustment and primary frequency regulation.
"The source-network-load-storage real-time collaborative control system is the dispatching center of Guangshui's 100% new energy new power system, which is equivalent to the 'brain' of the operation of the entire demonstration project. When the new energy output is in profit or loss, energy is stored and released through energy storage. , demand-side response for peak shaving and valley filling, and energy routers for two-way control of power flow to achieve power balance and ensure 100% new energy stable power supply." Hu Pan told reporters that the accuracy and effectiveness of its control strategy are directly related to the demonstration project The safety and stability of the project is the key to the smooth operation of the project.
According to reports, the operation control of the traditional power system relies on day-ahead load forecasting and off-line safety checks to formulate the next day's operation mode to achieve system stability and power balance.
In the new power system with a high proportion of new energy, new energy power generation fluctuates randomly, rapidly, and in a large range. Flexible loads such as electric vehicles and energy storage cannot be accurately predicted. Multi-time scale power balance is difficult, and traditional models are difficult to adapt.
In this regard, the demonstration engineering team specially developed a real-time collaborative control system for source, network, load, and storage based on cloud computing and artificial intelligence technology, which has the potential for dynamic voltage and frequency control, refined weather analysis, 5-minute super-imminent power generation prediction, and source, network, load, and storage adjustment. Functions such as judgment, control strategy deduction, and real-time collaborative control of source, network, load, and storage.
The system can realize the panoramic and whole-process monitoring of the source, grid, load, and storage operation in the Guangshui County Demonstration Area. Through the multi-level operation of the whole process monitoring, according to the latest operating status of the grid, the deployment of the source, grid, load, and storage in the grid resources on all sides to realize real-time optimal operation of the power grid.
Relying on this system, even if the new energy power generation fluctuates violently, it can respond quickly to ensure the safe and stable operation of the power grid.
"For example, once the system monitors problems such as insufficient output of new energy power generation, the system can respond within a few milliseconds at the fastest. The source side realizes friendly grid connection and active support, the grid side carries out power flow optimization control, and the load side develops demand. In response, the storage side performs rapid power stabilization control." Liu Ju told reporters.
Not only that, the demonstration engineering team has equipped more than 70 sets of new relay protection devices at the key nodes of Guangshui's 100% new energy new power system to ensure rapid and accurate fault removal.
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A demonstration project, a series of key technologies, a new model, and a green energy sample.
"The demonstration project has entered the countdown to completion and commissioning. Soon, within 418 square kilometers of Guangshui, 100% new energy independent power supply time will account for more than 70% of the year, and the annual new energy power supply will account for more than 80%." Wang Wei told reporters.
(China Discipline Inspection and Supervision News)