Microgrid Energy Storage System's Primary Functions
A new energy microgrid can be constructed on the foundation of energy storage, which is a crucial component of the "collection-generating-transmission-distribution-use-storage" power system. Wind energy and photovoltaics, two forms of new energy power generation, fall under the category of intermittent power generation, which is clearly unstable and plagued by "wind desertion" and "limited power output."
New energy microgrids can be made more stable and have better power quality by buffering electrical energy using an energy storage device. Therefore, what function does the renewable energy storage system perform in the microgrid?
The development of the smart grid depends in large part on the microgrid.
It is capable of integrating internal power supply and load operation, coordinating and controlling with the main power grid, establishing a secure connection to the main power grid, or operating independently.
It can also satisfy or even exceed the user's demands for power quality, power reliability, and safety.
When the microgrid and main grid are both operating normally, they are connected to the grid, and the electricity produced by the microgrid will be used first to satisfy the demands of the local user load.
The microgrid system will actively detach from the main grid and run independently to ensure that the main load continues to function normally in the event of a main grid breakdown or significant power quality issues.
1. The microgrid's energy storage system can increase the reliability of distributed energy
Generally speaking, external environmental factors like light, temperature, wind power, climate, and other factors have an impact on distributed energy sources like solar energy, wind energy, biomass energy, and other renewable energy sources. This causes the power generation to be unpredictable and unstable.
The output power of the distributed energy in the microgrid changes with the change in environmental conditions, and it is unable to offer a constant output for the load when the microgrid is detached from the power grid and runs independently.
The micro-grid uses the energy storage system. The main grid, the energy storage system, and the distributed energy are all cooperatively managed by the energy management system (EMS), which may stabilize the output, reduce volatility in the distributed energy, and offer local distribution of the distributed energy. Use caution while transmitting across long distances to the main grid to prevent transmission pressure and power loss.
Additionally, to cut down on the duration of power outages, the energy storage system can continue to supply some of the energy for the main load at night or while distributed energy is being maintained.
2. The microgrid's energy storage system can enhance the power quality of the user's electricity.
The power quality of the microgrid must meet the applicable national criteria before it can be linked to the main grid; specifically, characteristics like power factor, voltage asymmetry, current harmonic distortion rate, and voltage flashover must be at comparable levels.
Due to the properties of its own energy, the microgrid cannot ensure the quality of the electricity, particularly the voltage stability, in the absence of an energy storage system.
The use of an energy storage system can significantly contribute to the microgrid's power quality enhancement. In order to stabilize the energy output and address voltage dips and sags, the system adjusts the active and reactive power output by the energy storage system to the microgrid. This is done by managing the energy storage PCS.
The energy storage system of the microgrid can provide fast power buffering, quickly absorb/supplement electrical energy, provide active and reactive power assistance, and moderate voltage variations in the face of issues such voltage swells and dips in the main grid. For the microgrid, the energy storage system can also perform some harmonic control duties.
3. The microgrid's energy storage system can modify the peak
When the load is low, the energy storage system in the microgrid can store any excess power produced by the distributed energy resources, release it when the load is at its highest point, and change the load demand.
The energy storage system is essential to the microgrid system because it serves as the microgrid's energy buffer link. While still meeting peak load power demand, the energy storage system of the microgrid can lower the needed capacity of the generator set or transformer.