BATTERY REMAINING-POWER METER AND REMAINING-POWER CALCULATION METHOD

摘要

PROBLEM TO BE SOLVED: To enable cheaply and highly accurately calculating the remaining power by providing a memory means and the like holding a data table correlating the terminal voltage of a battery at a specific discharge current or discharge power with battery remaining power. SOLUTION: A current sensor 3 is connected on the supply line from a battery 2 to a load M, detects battery discharge current or charge current, converts the amplitude of current to a current value signal having voltage values and outputs to an operator amplifier 4. An analog multiplexer 6 switches connection state by the command signal from a microcomputer 8 and outputs the analog output signal of amplifiers 4 and 5 selectively to an A/D converter 7. The converter 7 outputs the signal to a CPU 8. Using a program and data table installed in the CPU 8, the integrating calculation method of inventory is combined by a correction process with remaining power calculation using a terminal voltage.