A passive and isolated battery voltage monitoring method
Cai Xia Xu · Advanced Technology of Electrical Engineering and Energy · 2011
In battery energy storage technology,a large number of batteries in series bring a high battery terminal voltage which brings difficulties to the voltage detection and capacity monitoring.A passive and isolated battery voltage monitoring method is proposed based on correcting the linearity of digital optocouple.This voltage monitoring circuit consists of four parts: digital optocoupler isolation circuit,current-voltage conversion circuit,signal conditioning circuit and voltage reference section.In this paper,transmission characteristics and temperature drift characteristics of the optocoupler are analyzed,and piecewise linear correction method is proposed.Finally the experiment results show that this method can easily solve the isolation problem of high voltage and low voltage.Moreover,the passive voltage monitoring is also achieved with a low cost.