Energy storage power stations are established to regulate peak and valley electricity consumption. Energy storage power stations are composed of energy storage units, auxiliary facilities, access devices, and measurement and control devices. The establishment of energy storage power stations aims to store the electricity we waste during low peak periods and release it back into the grid during peak periods, in order to achieve the goal of peak shaving and valley filling.

Energy storage stations can store electricity and release it when needed, effectively solving the imbalance of electricity in time and space. The application of energy storage power station technology runs through all aspects of power generation, transmission, distribution, and consumption in the power system. Realize peak shaving and valley filling in the power system, smooth and track fluctuations in renewable energy generation, efficiently regulate system frequency, and increase power supply reliability.

The application of grid side energy storage can improve the efficiency of grid utilization, participate in auxiliary services in the electricity market, improve power supply reliability, and promote the consumption of new energy. Mainly planned in the vicinity of ultra-high voltage direct current, high penetration areas of new energy, and load center areas.

The following are the main components of a typical battery storage power station system:

1. Transformers and high-voltage switchgear: convert the grid voltage (10KV, 6KV or other levels of voltage) transmitted from the grid into the voltage level required for the user's electrical appliances and electricity consumption (such as 0.4KV)

2. Low voltage switch and control cabinet: used for control and management of charging and discharging and electrical energy output

3. Control system: The battery energy storage system is controlled by a programmable logic controller (PLC) and a human-machine interface (HMI). One of the key functions of the PLC system is to control the charging time and rate of the energy storage system. It is integrated with the rest of the system through standardized communication inputs, control signals, and power supply. It can be accessed through dial-up or internet. It has multiple defense layers to restrict access to its different functions, and provides customized reporting and alarm functions for remote monitoring.

4. Power Conversion System (PCS): The function of a power conversion system is to charge and discharge batteries, and provide improved power quality, voltage support, and frequency control for the local power grid. It has a controller (DSP) that can perform complex and fast actions, multiple quadrants, and dynamics, with dedicated control algorithms that can convert outputs throughout the entire range of the device, i.e. cyclically absorbing from full power to full power output. Currently, bidirectional inverters are commonly used.

5. Battery matrix (stack): A battery matrix (stack) is composed of several single cells.

6. Battery energy storage systems can be used to save fixed equipment investment in the power grid system; Improve the utilization rate of power grid equipment and reduce the cost of use for end-users. Energy storage systems can reduce the peak energy load of users at the distribution end, which will promote the utilization of power grid equipment and meet the needs of end customers. The load factor of the power grid is thus improved.

Battery energy storage systems can serve as a buffer between various power sources and stable electricity demand, increasing the power generation capacity and legal quality of unstable sources such as wind and solar energy. It can also be used for peak shaving and valley filling for general power grid distribution users. The electricity at the peak electricity price is stored in the battery matrix (stack) in the form of DC electricity. During the peak electricity price period, it is outputted to various electrical appliances and users at the power frequency (50Hz), which is equivalent to using electricity at a low price period during the high price period. The price difference is the benefit of peak valley energy storage energy saving.