As a precision component of the vehicle power system, the core function of the EBS is to ensure the stability of battery performance by accurately calculating the state of charge (SOC). Simply put, SOC is determined by a formula: SOC=Q_T25_120/C-nom, where Q_T25_120 is the energy of the battery discharged to an open circuit voltage of 10.5V at 120A at room temperature of 25°C, and C-nom is the rated capacity of the battery. The accuracy of this value directly depends on the real-time measurement of voltage, current, and temperature.
During vehicle operation, EBS continuously calculates SOC in LIN network mode, and updates it at least once every hour in monitoring mode. After the battery is powered on, EBS performs a fast SOC calculation to obtain the initial state. This process uses battery voltage, current, temperature data and pre-coded battery parameters to ensure that the error is controlled within +/-15% under specific conditions (such as load current less than 20A, SOC value greater than 30%, and at room temperature).
Under certain conditions, such as no charging and discharging within the first 24 hours after power-on reset, and with valid battery type coding and BSD data, EBS will start a new round of fast SOC calculation. If the voltage value at the 10th second is higher than the 1st second and lower than 13.5V, EBS will trigger a new calculation process, BSD will be reinitialized, and the most recent SOC value will be sent to the LIN network.
In summary, the sophisticated design and precise calculation of EBS are the key to ensuring the stable operation of the vehicle power system. However, in actual application, it is important to follow its technical guidelines to give full play to its performance and measurement accuracy. This is a reflection of the rigorous attitude towards product quality.