Reliable grid-connection of a high proportion of new energy requires a large number of flexible regulation resources to participate in power balance and frequency/peak regulation.

With the increasing proportion of flexible resources on the power side, the importance of flexible resource regulation on the load side tends to increase.

Load-side response technology refers to power users temporarily change their habitual mode of consumption according to price signals or incentives, which can reduce or shift the power load for a certain period of time to ensure the stability of the power system.

Sensing, predicting and aggregating a large number of adjustable loads and evaluating their adjustable potential can help to improve the response scale and rate of adjustable loads and give full play to the regulating role of demand response. However, the analysis techniques and research methods for the resource potential of adjustable loads in typical industries need to be verified.

As of September 2021, a total of 14 provinces (covering 15 provincial companies) in the business area of State Grid Co., Ltd. have issued demand response support policies and established adjustable load resource libraries; The total contracted peak load is about 5.85× 107kW, and the remote control load accounts for about 20% of the peak load; The total contracted grain filling load is about 1.49× 107kW, and the remote control load accounts for about 6% of the grain filling load.

Adjustable load resources participate in the interaction of the power grid, build a "cloud, pipe, edge, end" technical support system, and develop the main station, terminal and other equipment and successfully applied to demonstration projects. It should also be noted that these devices still lack a test verification environment in terms of inspection test specifications and load resource interconnection.

The scale of flexible load resources on the demand side of China is huge (the estimated value in 2030 is 1.08×108 kW), but the actual use of load resources to participate in the interaction of source, network, load and storage capacity is small every year.

In the face of the new situation of energy and power development, it is urgent to promote the flexible and efficient application of demand-side adjustable load resources to cope with the peak power gap of the grid, the participation of demand-side resources in power market transactions, and the load regulation based on peaking and valley TOU, so as to promote the marketization, normalization and large-scale development of demand response services.

In the aspect of technology research, the potential analysis of adjustable load, load control, inspection and testing are the key research directions.

Virtual power plant can aggregate all kinds of distributed power supply and demand-side response resources, and it is also a new idea to supplement flexible adjustment resources and solve the problem of system frequency modulation under the grid-connected state of high proportion of new energy power generation.

Virtual power plant aggregates distributed resources, controllable loads and energy storage devices in the power grid into a virtual controllable aggregate to participate in the dispatching and operation of the power grid. Because of the aggregation of distributed power supply and a variety of demand-side response resources (such as energy storage, electric vehicles, residential/commercial HVAC loads, etc.), it has fast and accurate dynamic response capability and good frequency modulation effect.

The application of demand-side response technology to control the virtual power plant will play a significant role in improving the ability of peak and frequency regulation, ensuring the stability of system frequency, and improving the reliability and security of power grid operation.

In recent years, the technology related to using virtual power plants to participate in power grid FM has been widely concerned by the power industry. Several virtual power plants have been built abroad to participate in power grid FM demonstration projects, such as the RegModHarz renewable energy project in north-central Germany. Limejump's Balanced Plan virtual power plant project in the UK, Anesco's 10-megawatt battery energy storage system project, and Tokyo Electric Power Company's promotion of electric vehicle applications connected with virtual power plant systems.

In China, the representative large-capacity energy storage battery demonstration projects include Zhangbei Fengguang Storage Demonstration Base, Shenzhen Baoqing Energy storage Power Station, Shanghai Caoxi Energy conversion Comprehensive Exhibition base, Shanghai Huangpu District commercial building virtual power plant project, etc., preliminary test the frequency modulation function of the participation system, but it is still in the initial stage.

In the future, the aggregation of FM resources in virtual power plants and the quantitative evaluation of FM capabilities, the development of virtual power plant flexibility characterization and aggregation methods, market participation methods, and fully tap the scheduling potential of internal demand-side resources are important aspects of technological development.