Principle of Energy Management System
In energy storage power plants, energy storage batteries are often composed of tens or even hundreds of strings of batteries or more. As the batteries are in the production process and in use, it can cause inconsistencies in parameters such as internal resistance, voltage and capacity of the battery. This difference is manifested as different voltages between the series cells when the battery pack is full or discharged, or different energy. This situation can lead to partial overcharge, while in the discharge process the voltage is too low cells may be over discharged, the overall capacity drops sharply, the entire battery pack shows the capacity of the battery pack in the capacity of the worst performing cells, eventually leading to early failure of the battery pack.
Therefore, for lithium iron phosphate battery pack, the equalization protection circuit is a must. OSM Battery has a solid R&D team, dedicated to the development of BMS battery management system and battery energy storage products. And battery energy storage products. The company’s battery can be used with the common energy storage inverter, forming a “photovoltaic + energy storage” system, electricity self-generation, not only can save electricity bills, but also can make the home never lose power.
Single cell voltage equalization function
This function is to correct the dispersion of voltage or energy in the series connected battery pack caused by the difference of battery cells’ own process, to avoid the occurrence of individual cells’ performance deterioration or even damage due to overcharge or over discharge, and to make all individual cells’ voltage difference within a certain reasonable range.
Battery pack protection function
Single battery over-voltage, under-voltage, over-temperature alarm, battery pack over-charge, over-discharge, over-current alarm protection, cut-off, etc.OSM Battery has independently developed several products such as high stability BMS battery management system, wall-mounted low-voltage home energy storage, floor-mounted low-voltage home energy storage and compact commercial energy storage.
Diagnostic function
The BMS should have the analysis and diagnosis function of battery performance, which can, based on the real-time measurement of battery module voltage, charging and discharging current, temperature and terminal voltage of single battery, calculated internal resistance of the battery and other parameters, produce the diagnosis of current capacity or remaining capacity (SOC) of single battery, the diagnosis of single battery state of health (SOH), the assessment of battery pack state, and the estimation of current.
Thermal Management
During the charging process of Li-ion battery module, a large amount of heat will be generated, which makes the temperature of the whole battery module rise, thus, the BMS should have the function of thermal management.
Fault diagnosis and fault tolerance
In case of abnormality, the BMS should give fault diagnosis alarm signal and send it to the upper control system through the monitoring network.
The management system has a self-test function for the system’s own software and hardware, so that even if the device is damaged, the battery safety will not be affected. OSM Battery products have export certificate (UN38.3, MSDS), with full capability of sea transportation.
Other protection technologies
For the battery over-voltage, under-voltage, over-current and other fault conditions, the protection is taken to cut off the circuit.
On-line battery capacity evaluation SOC
Based on the measurement of dynamic internal resistance and true voltage, etc., a mathematical analysis and diagnostic model is established to measure the remaining capacity SOC by using the correspondence between charging characteristics and discharging characteristics and using a multimode segmentation process.