can be stored. At present, according to the classification of storage media, energy storage technologies are mainly divided into five categories: physical energy storage, electrochemical energy storage, electrical energy storage, chemical energy storage and thermal energy storage.

In today’s era, the energy Internet with “smart grid + UHV grid + clean energy” as the main body has become a trend. Large-scale development of renewable and clean energy such as wind energy and solar energy has become a trend to promote the transformation of energy consumption structure to a low-carbon and clean direction. important global consensus.

In actual operation, new energy power systems such as photovoltaics and wind power often have problems such as insufficient power consumption, which causes power waste to a certain extent. By adding energy storage links to the system, the tradition of instant power consumption can be changed. The model makes the “rigid” power grid flexible and flexible, thereby solving the consumption problem and improving the safety, economy, and flexibility of power grid operation.

Energy storage can not only improve the efficiency, safety and economy of conventional power generation and transmission, but also an important means to achieve smooth fluctuations, peak and frequency regulation of renewable energy, and meet the large-scale consumption and integration of renewable energy. Therefore, energy storage plays a pivotal role in the future energy Internet, and it is imperative to develop energy storage.

The significance of photovoltaic energy storage

Through the analysis of the characteristics of photovoltaic power generation, it can be seen that the impact of photovoltaic power generation system on the grid is mainly caused by the instability of photovoltaic power supply. It will have adverse effects on line flow, system protection, grid economic operation, power quality and operation scheduling. The grid-connection of photovoltaic power plants, especially the impact of large-scale photovoltaic power plant grid-connection to the Sui Sian Network, cannot be ignored. At present, the way to solve the impact of photovoltaic power plants on the grid is to improve the flexibility of the grid or to configure energy storage devices for grid-connected photovoltaic power plants.

The role of energy storage systems in photovoltaic power plants is mainly reflected in the following aspects:

1) Ensure system stability. In the photovoltaic power station system, there is a large difference between the photovoltaic output power curve and the load curve, and both have unpredictable fluctuation characteristics. The energy storage and buffering of the energy storage system enables the system to operate in a stable output level.

2) Energy backup. The energy storage system can play a backup and transition role when the photovoltaic power generation cannot operate normally. For example, when the battery array cannot generate power at night or on a rainy day, the energy storage system will play a backup and transition role. Depends on load requirements.

3) Improve power quality and reliability. The energy storage system can also prevent the grid fluctuations caused by the voltage spikes on the load, voltage drops and other external disturbances from having a large impact on the system. Using enough energy storage systems can ensure the quality and reliability of power output.