Charge control system for use in internal combustion engine

摘要

A charge control system for an internal combustion engine which is capable of suppressing electromagnetic noise due to a control signal to a generator, and which prevents overcharging a battery even if an input terminal receiving the control signal is grounded. The charge control system is composed of a generator 1 driven by an engine of a motor vehicle and a battery 4 charged with the output of the generator 1. Also included in the system is a computer unit 2 comprising a microcomputer CPU for calculating a target voltage Vreg on the basis of the operational states of the motor vehicle for comparison with a battery voltage Vb so as to output a drive signal in accordance with the comparison result. This drive signal operates a transistor Tr, incorporated into the generator, to control a field current 1f of the generator 1 so that the quantity of the power generation of the generator 1 increases and decreases to control the quantity of the charge to the battery 4.