Electronic ampere-hour meter for electric vehicle - modulates and amplifies voltage drop followed by demodulation and integration

摘要

The electronic ampere-hour meter is designed for use in electric vehicles. It measures the amount of hours consumed by such vehicles. The primary measurement input is the voltage drop (U1) obtained by passage of the motor current(Iv) through a standardised shunt resistor (S). this shunt resistor is connected to the input of a modulator (MD) whose AC output is passed to an amplifier (AA) and a demodulator (DM). The DC output of this demodulator feeds an integrating circuit (IE). This produces a series of pulses in accordance with the integral of the current, and the pulses are fed to a display unit.