Distributed Energy Storage System is a software system for monitoring and managing distributed energy storage plants. In simple terms, distributed energy storage plants for the same project may be distributed in different locations, making monitoring and management difficult. However, with the support of the software system, efficiency can be greatly improved.
The specific functions of distributed energy storage system
- Manage cross-regional on-site energy storage systems.
- Implement different strategies (e.g., peak-valley mode, demand mode, smooth mode, etc.) for various on-site energy storage systems.
- Related independent energy storage stations can be centralized as virtual energy storage stations for unified management and centralized dispatching.
- Users are isolated from each other, and each user can monitor their own energy storage station within their authorized range.
- Support web browsing and mobile client.
- Support local storage and cloud storage.
Distributed Energy Storage System can absorb peak power and inject power during sudden decrease in power supply by adjusting the load. On-site energy storage can alleviate power fluctuations caused by renewable energy production and output. Distributed Energy Storage System has flexible access locations and is currently used in medium and low voltage distribution networks, distributed generation and microgrids, and user applications.
Roles of Distributed Energy Storage Systems
Peak Shaving and Valley Filling
In recent years, the disparity between peak and off-peak loads in the power grid has been increasing. The growing penetration of renewable energy generation further exacerbates the need for peak load management.
Utilizing energy storage devices, like power conversion systems, to discharge during high-demand peak periods and charge from the grid during low-demand valleys reduces peak load requirements and saves electricity costs. This approach aims to enhance load characteristics and participate in grid peak shaving. By implementing peak shaving and valley filling strategies, the utilization of power system equipment can be improved, and the need for expansion and upgrades of generation, transmission, and distribution equipment can be deferred or reduced.
Enhanced Power Supply Reliability and Energy Quality
To prevent significant economic losses for critical users during grid faults or power outages, configuring a certain capacity of energy storage systems as emergency or uninterrupted power sources effectively enhances power supply reliability.
Furthermore, energy storage systems can facilitate efficient and rapid active and reactive power control. They can quickly respond to system disturbances, adjust frequency and voltage, compensate for load fluctuations, improve system stability, and enhance energy quality.
Frequency Regulation
Energy storage systems, especially battery energy storage technology, offer advantages such as rapid response and bidirectional regulation capabilities, making them more efficient than traditional frequency regulation methods. However, due to economic constraints, the capacity of battery energy storage systems for frequency regulation is smaller compared to traditional sources. Therefore, energy storage systems often combine with traditional frequency regulation sources for participation.
In terms of primary frequency regulation, research has focused on control strategies that utilize energy storage systems to assist conventional generating units, employing improved droop control methods.
Energy storage systems can also enhance the primary frequency regulation capability of wind power units when combined with wind power, reducing wind curtailment accordingly.
For secondary frequency regulation, addressing issues such as slow response and low ramp rates of conventional generating units, various methods have been proposed to enhance grid frequency regulation performance by employing energy storage systems, including fuzzy control, genetic algorithms, and sensitivity analysis.
Integration of Distributed Renewable Energy
The stochastic and fluctuating nature of distributed renewable energy sources like wind and solar power can impact the operation and control of distribution networks.
Energy storage systems can mitigate fluctuations in active power from distributed wind and solar generation, improve energy quality, and enhance tracking and planning capabilities. This approach reduces the impact of distributed renewable energy on the grid, promoting the integration of highly penetrated distributed renewable energy generation into the power grid.