The inevitable choice for new power systems - Ankerui electrochemical energy storage power management system solution

Ankerui 18721502664 Meng Xinyuan

Construction background

Implement the requirements of the "Opinions of the CPC Central Committee and the State Council on Completely and Accurately Implementing the New Development Concept and Doing a Good Job in Carbon Peaking and Carbon Neutrality " and the " Notice of the State Council on Issuing the Action Plan for Carbon Peaking before 2030 " , and incorporate green and low-carbon development into the national education system.

On March 26, 2021, in order to promote the deep integration of information technology and education and teaching , the Ministry of Education issued the " Specifications for the Construction of Digital Campuses in Higher Education Institutions (Trial) "

Abstract: This paper mainly introduces the solution of source-grid-load-storage linkage based on the new power system . Through advanced information communication technology and software system , it realizes the aggregation and coordinated optimization of distributed energy such as distributed power sources , energy storage systems , controllable loads , electric vehicles, and charging piles , so as to participate in the power market and power grid operation as a special power plant . The virtual power plant is not a real power plant , but a smart grid technology that uses a distributed power management system to participate in the operation and dispatch of the power grid to achieve the "source-load- grid " aggregation optimization.

Keywords: virtual power plant, source-grid-load-storage , carbon peak and carbon neutrality, photovoltaic storage and charging

1. What is a virtual power plant: aggregation and optimization of distributed resources

According to the article "The Concept and Development of Virtual Power Plants", a virtual power plant ( VPP ) is a power coordination management system that uses advanced information and communication technologies and software systems to achieve the aggregation and coordinated optimization of distributed energy sources such as distributed power sources, energy storage systems , controllable loads , electric vehicles , and charging piles , so as to participate in the power market and power grid operation as a special power plant . A virtual power plant is not a real power plant but a smart grid technology that uses a distributed power management system to participate in the grid operation and dispatch to achieve "source-load network " aggregation optimization .

Virtual power plants have strong flexibility and adjustment capabilities. Virtual power plants do not actually generate electricity, but integrate and regulate dispersed sources, networks, loads, storage and other elements , and become a controllable power source with strong flexibility and adjustment capabilities. They can be used as a power source to supply power to the power system, or as a power source for the load consumption system.

It also has the ability to adjust the load upward and downward . The core of the virtual power plant is the energy management system that aggregates resources, and its foundation is distributed, flexible resources and the power market . The virtual power plant is essentially an energy management system , so the intelligent software platform and centralized control system are the core of the virtual power plant . Distributed energy and flexible resources that participate in the scheduling and control of the software platform are the resource basis of the virtual power plant . Under the control of the energy management system , flexible resources also need to further consider factors such as demand response and uncertainty , and realize energy exchange with the large power grid through information communication with cloud centers , power trading centers, etc. , to achieve profitability . Therefore, market mechanisms such as the power market are the market basis for virtual power plants to achieve profitability.

2Why do we need a virtual power plant?

2.1 The demand for valley filling brought about by the rapid increase of wind and solar power

The speed of photovoltaic construction far exceeds that of wind power, and distributed photovoltaic has become the main force. In 2022, China 's photovoltaic installed capacity will exceed wind power for the first time.

Distributed power has made an indelible contribution. In 2022 , distributed photovoltaic power added 51.11 GW , accounting for 58.48% of all photovoltaic power additions that year ; as of 23H1, the cumulative distributed installed capacity reached 198.23 GW . Distributed construction and site selection are simple, the project cycle is short, and the installed capacity is fast. Due to its highly concentrated output time, the degree of grid dispatching and control is relatively low, and the problem of absorption is emerging. Shandong, Henan and other provinces with large distributed installed capacity have issued distributed storage documents.

(Picture from Huafu Securities' special report on virtual power plants)

Some provinces in China, represented by Shandong, also have obvious demand for valley filling. Shandong's installed capacity structure is similar to that of CAISO .

By the end of 2022 , the proportion of photovoltaic installed capacity reached 22.5%. During the May Day holiday in 2023 , the electricity load in Shandong Province dropped by about 15%.

This has led to a continuous negative electricity price phenomenon. It is worth noting that the spot price curve from April 29 to May 1 is similar to the duck curve, with negative electricity prices appearing frequently from 10:00 to 15:00 , which is the peak period for photovoltaic power generation. Combined with the fact that Shandong previously divided the noon period into a period of deep valley in electricity prices, the increase in new energy installed capacity has changed the original load curve , resulting in a deep valley in the net load of the power grid during the period of concentrated new energy generation . It is necessary to transfer the load in time (fill the valley) to smooth the change and promote the consumption of new energy.

2.2 New loads such as charging piles increase the complexity of the load side

The number of charging piles has increased rapidly with the rapid increase of new energy vehicles, changing the distribution network. As of 2023H1 , China's public charging piles have 2.1486 million units, up 40.63% year-on-year. In 2023H1, the sales of new energy vehicles increased by 44.13 % year-on-year, maintaining rapid growth. It can be foreseen that as the sales of new energy vehicles continue to increase rapidly in the future, the number of charging piles will continue to increase. The large increase in charging piles will have an impact on the distribution network. Compared with conventional AC charging piles, fast-charging DC piles have a greater impact due to their higher power and shorter charging time.

Charging piles increase the peak load of residents' daily electricity consumption. The impacts of charging piles on the distribution network mainly include:

(1) The peak electricity consumption of charging piles is also the original peak electricity consumption of residents, which will cause the original load peak to continue to increase, resulting in a short-term and high-level peak load;

(2) Transformer capacity is configured according to peak load, resulting in idle resources at other times;

(3) Charging load fluctuations lead to network losses, etc.

Therefore, the development of charging piles has led to an increase in the demand for peak-shaving and valley-filling. However, charging piles and new energy vehicles are good adjustable loads. If they can be aggregated and optimized through virtual power plants, it will be a win-win option to reduce charging costs and grid investment .

2.3 The demand-side response capability strives to reach 3%-5% of the maximum load

The goal of building demand-side response capabilities is clear. Before the 14th Five-Year Plan, virtual power plants remained in the pilot stage of individual regions and projects. First, the proportion of new energy installed capacity was not high, and the power system did not have strong demand for flexible resources; second, there was a lack of quantitative targets . In 2022 , the " 14th Five-Year Plan for Modern Energy System" proposed that by 2025 , the power demand-side response capability will reach 3% to 5% of the maximum load , among which East China, Central China, and South China will reach about 5% of the maximum load .