Superconducting energy storage systems utilize superconducting coils to directly store electromagnetic energy, which can then be fed back to the power grid or other loads when needed. They can also flexibly manage voltage dips and harmonics in the power grid, or provide transient high-power active power support.
I. Principle of Superconducting Energy Storage System
The working principle of a superconducting energy storage system is as follows: During normal operation, the grid current charges the superconducting inductor through rectification, and then maintains a constant current operation (because superconducting coils are used for energy storage, the stored energy can be stored permanently with almost no loss until it needs to be released). When the grid experiences transient voltage drops or surges, or transient active power imbalances, energy can be extracted from the superconducting inductor, converted into AC by an inverter, and output to the grid with flexibly adjustable active or reactive power, thereby ensuring the stability of the grid's transient voltage and active power balance.
II. Characteristics of Superconducting Energy Storage Systems
1. Superconducting energy storage systems can store energy for a long time without loss, with a conversion efficiency of over 90%.
2. Superconducting energy storage systems can be connected to the power grid by using power electronic devices for power conversion technology, with a fast response speed (millisecond level).
3. Since the capacity of its energy storage and power modulation system can be independently selected over a wide range, the superconducting energy storage system can be built into the required high-power and high-energy system.
4. Superconducting energy storage systems have no rotating parts other than the vacuum and cooling systems, resulting in a long service life.
5. Superconducting energy storage systems are not limited by location during construction, are simple to maintain, and produce little pollution.
Superconducting energy storage systems can be used to regulate peak and valley loads in power systems, reduce or even eliminate low-frequency power oscillations in the power grid to improve the voltage and frequency characteristics of the power grid, and also to regulate reactive power and power factor to improve the stability of the power system.
