Design and application of light storage anti backflow control in a certain machinery factory

Li Mingjun

Ankerui Electric Co., Ltd. Shanghai Jiading202505

Abstract:Against the backdrop of the "dual carbon" goal and the construction of new power systems, the demand for anti backflow in photovoltaic distribution and storage scenarios is becoming increasingly prominent. This article focuses on the collaborative anti backflow technology of photovoltaic energy storage, analyzing how it accurately solves the problem of surplus electricity from photovoltaic systems being sent back to the grid through the dual core drive of "intelligent monitoring+dynamic regulation", avoids the risk of fines, and improves energy returns. The solution integrates efficient energy storage systems and anti backflow devices, using real-time control strategy algorithms to control photovoltaic power generation, energy storage charging and discharging, and load demand, ensuring spontaneous self use, reducing the frequency of anti backflow comprehensive protection tripping, and minimizing the loss of abandoned light; Simultaneously supporting peak valley arbitrage and demand management to reduce enterprise electricity costs. By combining scenarios such as industrial and commercial parks and household solar energy storage, demonstrate how technology can adapt to complex power grid environments, assist users in compliant operations and long-term benefits, and provide a safe, economical, and sustainable one-stop solution for energy transformation.

Keywords:Distributed photovoltaics, distributed energy storage, photovoltaic energy storage coordination, anti backflow control, energy management, and protective devices.

1 Overview

Under the current policies of 430 and 531, full grid connection of photovoltaics is no longer allowed. After June, the grid connection price of photovoltaics will also become a floating price. Photovoltaic distribution and storage are imperative, mainly due to the following reasons:

（1） Policy coercion:

Most advanced domestic regionsClearly require new photovoltaic projects to have a capacity of 10% -20% and a 2-hour storage capacity, and include energy storage in the grid access conditions; With the rapid increase in photovoltaic installed capacity, the carrying capacity of the power grid is approaching saturation, especially in the central and eastern regions where the pressure of distributed photovoltaic consumption is prominent. The policy of mandatory allocation and storage can use energy storage to stabilize power generation fluctuations, reduce the phenomenon of abandoned solar energy, alleviate the pressure of power grid regulation, and reduce the saturation of power grid consumption (especially distributed photovoltaics). Mandatory allocation and storage can stabilize fluctuations and reduce abandoned solar energy.

（2） Technical necessity：

Photovoltaic power generation has intermittency and unpredictability, and energy storage systems can adjust power output in real time, reducing the impact on grid frequency and voltage and improving power qualityThrough the "photovoltaic+energy storage" mode, surplus electricity during the day can be stored for use at night or on rainy days, reducing dependence on the power grid and maximizing energy benefits for users.

（3） Economically feasible:

energy storageThe cost of battery cells continues to decrease，At the same timeThe energy storage system can achieve peak valley arbitrage by charging during low electricity price periods and discharging during high electricity price periods. Matching auxiliary service revenue, payback periodSignificantly shortenedLight storage electricitycomprehensivecostdropLow, highlighting economic efficiency.

（4） Transformation support:

Energy storage enhances the frequency regulation and voltage support capabilities of the power grid, supports the "dual carbon" goal (typical projects reduce carbon emissions by thousands of tons per year), and combines mature grid type energy storage technology to drive new energy from "passive grid connection" to "active support", accelerating the reconstruction of the energy system.

（5） Future trends：

The core logic of mandatory photovoltaic storage is the combination of policy compliance, technological necessity, and economic feasibility. In the short term, policy pressure and bottlenecks in consumption are direct drivers; In the long run, advances in energy storage technology and cost reductions will make it an inevitable choice for energy transformation.

2. Project situation

Shandong Longqiang Machinery Manufacturing Factory Distributed Photovoltaic Storage Coordination Project Photovoltaic Construction ProjecteyephotovoltaicThe total installed capacity of the construction is200kWThe installed energy storage capacity is 100kW/215kWhConstruction AreaLocated in Shouguang City, Shandong ProvinceThis project includes a photovoltaic power generation system1One transformer, one 150kW inverter, and one 50kW inverter. Among them, parallel branch points are set up1Here,Photovoltaic energy storage shares a grid connected cabinet.

Each inverter will convert the DC power output from the battery components into AC power (0.4kV), which will be led to the grid connected transformer via cables（0.4kV）lower end.After transformerAfter boosting to 10kV, it is connected to the local power grid through a transmission line and then connected to the 10kV external line.

According to the requirements of the local power company, this photovoltaic energy storage coordination project can only be consumed on-site and the surplus power grid is prohibited.

3solution

In order to achieve the above goals, anti backflow protection devices are installed at the common connection points. Once backflow is detected, a signal will be sent to the ACCU-100 coordination controller through the communication interface,By monitoring the power at the main incoming line of the municipal power supply and real-time generated power, the corresponding inverter regulation instructions and energy storage charging and discharging power instructions are generated through coordinated controller calculation to achieve flexible regulation of photovoltaic anti backflow function and energy storage consumption function of photovoltaic under the premise of anti backflowThis method can ensure that the power system operates according to design, protect the safety and stability of the power grid, and maximize the use of photovoltaic power generation to reduce energy costs for users. The control scheme is as follows:

The typical configuration of the plan is as follows:

The system networking diagram is as follows:

4. Plan effect

ACCU-100 Coordinated ControlBy distributingUnified resources of photovoltaics and energy storageIntegrate, monitor and manage, throughReal time monitoring of power values at the interaction points of the municipal power supply，The current situation of photovoltaic power generation and load electricity consumption can be analyzed, and the coordination controller can use the collected confidence for data analysis and strategy decision-makingReal time adjustment of various electricity demands based on loadphotovoltaicOutput power of the unitAnd the charging and discharging power of energy storageEnsure thatphotovoltaicThe power supply of the system is not reversed to the power gridat the same time，Control the energy storage system to further absorb photovoltaics. can eitherBefore the anti backflow comprehensive protection trips to the grid connected cabinet, the system issues inverter power adjustment commandsInstructions for charging and discharging power of energy storageTo achieve the goal of flexible regulation and improve the stability and reliability of microgrid systems.

5. Conclusion

The implementation of the anti backflow project for photovoltaic energy storage in our machinery factory not only ensures the efficient use of photovoltaic energy and the safety of the power grid, but also reduces the cost of production electricity through the flexible adjustment of the energy storage system and the coordinated operation of the intelligent management platform. This solution solves the problem of high energy consumption in industrial scenarios with the integrated thinking of "source grid load storage". It not only meets the policy compliance requirements of "self use and no grid connection for surplus electricity", but also creates direct economic value for enterprises through peak valley arbitrage and energy efficiency optimization. In the future, with the deep integration of grid based energy storage technology and smart energy platforms, this project will become a case of energy transformation in the mechanical manufacturing industry, promoting the acceleration of traditional industries towards low-carbon and intelligent production modes.

References:

[1] Zhang Kuizhong New Industrial and Commercial Park Photovoltaic Storage Charging Microgrid System under the Background of Dual Carbon [J]. Electrical Era, 2025, (01):42-44.

[2] Yu Bin, Pang Dan, Han Yongxiao, etc Research on Microgrid System for Load Control Optimization of Distribution Network [J]. China High tech, 2024, (22):91-93.DOI:10.13535/j.c0nki.10-1507/n.2024.22.32.

[3] Li Sheng, Hou Xiang Research on Power Control Technology for High Proportion Photovoltaic Energy Integration into Microgrid System [J]. Light Source and Lighting, 2024, (09):104-106.

[4] Cui Dong, Yang Wenbiao, and great grandfather Qin Development of anti backflow device for photovoltaic grid connected power generation [J]. Solar Energy, 2009, (12):41-42.

[5] Ankerui Electric Co., Ltd Acrel-2000MG Microgrid Energy Management System User Manual [Z]. Shanghai: Ankerui Electric, 2022

[6] Ankerui Electric Co., Ltd Technical Manual for AM5SE-IS Anti backflow Protection Device [Z]. Shanghai: Ankerui Electric, 2022