摘要 |
A remaining energy E of a battery is estimated based on a measurement of a momentary voltage and a momentary current. E is defined as a function of its voltage U or power owing to a characteristic function (E/U) or (E/P). Instead of the function, a lookup table can be used. E/U function is defined by using a reference battery having the same or similar characteristics. A set of low and high current or power loads are applied to the reference battery to cause voltage drops which are measured and then used to determine function (E/U) and a parameter Alpha which is specific to the type of reference battery. During the operation of the battery, momentary voltage and current are measured and Alpha is used to correct the momentary voltage. Afterwards, function (E/U) enables to estimate E. The battery size is used to scale E for a better estimation. |