The 'brain' Of Photovoltaic Energy Storage System

Photovoltaic power generation is a technology that directly converts solar energy into electrical energy. As is well known, the sun does not provide continuous energy - electricity generation is interrupted during rainy or nighttime weather, so energy storage devices, equivalent to a "large battery", must be equipped. When there is sunlight, the system charges the battery; When there is no sunlight, use the stored electrical energy in the battery. In addition, the electricity generated by photovoltaics is direct current, which must be converted into alternating current through an inverter in order to be used by households.
Our most common photovoltaic panels are installed on roofs or floors, and their raw materials come from sand in the desert. After purification, sand is used to obtain silicon material, which is also the basic material for manufacturing chips. The difference is that the purity of silicon material used in solar cells ranges from 99.996% (i.e. 4 9s) to 9 9s, while the purity of silicon material required for chips is as high as 11 9s.
Energy storage systems are divided into two categories: traditional and new. Traditional energy storage systems, such as hydropower stations, use electricity to pump water to high places when there is sufficient sunlight, and then release water to generate electricity when needed, using potential energy to generate electricity. However, hydropower stations are limited by geographical conditions, requiring sufficient water sources, differences in elevation, and extensive land occupation, making them difficult to popularize. In contrast, new energy storage batteries, such as lithium batteries, can be directly installed in household distribution rooms and have a wider range of applicability. In the future, energy storage technology will develop towards solid-state batteries, which have larger storage capacity and higher safety. Currently, the main challenge is cost, and it is expected to achieve mass production within five years.
Many people believe that the cost of photovoltaic power generation is high, but in reality, the cost of photovoltaic panels themselves has been significantly reduced. The real cost comes from the overall system of "photovoltaic+energy storage". Individual photovoltaic power generation cannot directly provide stable household use, and Spain has experienced widespread power outages due to several dark clouds, which is an example of insufficient energy storage. With the electric vehicle industry driving down the cost of lithium batteries, household energy storage has gradually gained a price advantage.

Inverter: The 'Intelligent Brain' of the System
Inverters play two key roles in the system:
1. Translator function: Convert the direct current generated by photovoltaics into household usable alternating current.
2. Intelligent commander: dynamically allocate electricity based on power generation and consumption.

• When there is sufficient sunlight, priority should be given to household use, and the remaining electricity should be used to charge the battery;
• After the battery is fully charged, excess electricity is integrated into the grid, and users can sell their electricity for profit;
• When photovoltaic power generation is insufficient, use battery energy storage first;
• After the energy storage is exhausted, it automatically purchases electricity from the grid.

This intelligent distribution method indicates that electricity prices will fluctuate in real time in the future: electricity prices will rise during peak hours and fall during off peak hours. Through intelligent scheduling, even cross regional electricity balance can be achieved, such as transferring office electricity to the peak electricity consumption of shopping malls on weekends.

The difference between photovoltaic inverters and energy storage inverters
Despite their similar names, the two have different functions:

• Photovoltaic inverter: specifically designed for photovoltaic power generation systems, it unidirectionally converts the direct current generated by solar panels into alternating current, which is then connected to the power grid or used by loads.
• Energy Storage Inverter (PCS): Used in energy storage systems, it has bidirectional regulation capability and can convert AC power from the grid to DC power to charge the battery, as well as convert DC power from the battery to AC power supply for the grid or load. In the event of a power failure, the photovoltaic inverter will stop working, while the energy storage inverter can continue to operate to ensure system power supply.

Photovoltaic systems convert solar energy into usable electricity, energy storage devices solve the problem of unstable power supply, and inverters undertake the dual tasks of DC/AC conversion and intelligent distribution. The collaboration of the three forms a closed loop of "power generation storage electricity consumption", which not only reduces energy costs but also promotes the development of smart grids. As the "brain" of the system, the inverter is the core equipment for realizing this clean energy cycle. At present, Chinese inverter companies have taken a leading position in the global market, laying a solid foundation for optimizing the future energy structure.