BMS and current sensors in battery management for new energy vehicles

BMS Battery Management System: the link between the battery and the user Battery Management System (BMS) is the link between the battery and the user, which can be used in electric cars, battery cars, robots, drones and so on. 　　

The most important function of BMS is to be able to improve battery utilisation, prevent overcharging and over-discharging of the battery, prolong the service life of the battery, and monitor the status of the battery.　

Specifically, the battery management system has the following three main functions:

First, it accurately estimates the charging state of the power battery pack, i.e., the remaining battery charge, ensures that the SOC is maintained within a reasonable range, prevents damage to the battery due to overcharging or overdischarging, and displays at any time the residual energy of the storage battery of the hybrid vehicle, i.e., the charging state of the storage battery.

Secondly, the BMS can also realise the function of dynamic monitoring. During the battery charging and discharging process, it collects the terminal voltage and temperature, charging and discharging current, and total battery pack voltage of each battery in the battery pack of the electric vehicle in real time, so as to prevent the battery from overcharging or overdischarging. At the same time, it can give the battery status in time, select the problematic batteries, maintain the reliability and efficiency of the whole battery group operation, and make the realisation of the remaining power estimation model possible.

Thirdly, to ensure the balance between the batteries, that is, for a single battery balanced charging, so that each battery in the battery pack to achieve a balanced and consistent state. Equalisation is a key technology for battery energy management systems that the world is currently working to research and develop.

Fourth, in general, the electric vehicle battery management system (BMS) is an important link between the on-board power battery and the electric vehicle, which integrates the monitoring and management of the battery or the battery pack, so as to ensure the safety and reliability of the battery or the battery pack, and output power in the best condition. 　

Current sensors can detect the charging and discharging currents in the BMS system, and in the field of new energy applications in the automotive sector, current sensors can be used to carry out accurate battery management of automotive batteries, as well as hybrid vehicle power battery packs. For example, the principle of electromagnetic induction can be used open-loop current sensors, in the isolation conditions, the AC current signal overcurrent protection, so as to facilitate the implementation of the switching output. Current Sensor and ArrangementCurrent sensors can be used in pure electric vehicle power batteries to connect to the BMS system to detect the charging and discharging currents and improve the efficiency of the vehicle battery. 　

　The current sensor has good accuracy and stability due to its electrically isolated measurement of DC, AC or pulse current. Thus, during the battery charging and discharging process, the BMS system can prevent the battery from overcharging or overdischarging by using the current sensors to collect in real time the terminal voltage and temperature, charging and discharging currents, and the total voltage of the battery pack of the power battery pack of the electric vehicle. 　

　In addition, relying on the current sensor, the BMS system level can also detect the battery power to give the battery condition in time, effectively prevent the emergence of battery leakage, insulation damage and local short-circuit situation, and then select the problematic battery, to maintain the reliability and high efficiency of the whole set of battery operation.