METHOD FOR CALCULATING STATE OF CHARGE OF UNINTERRUPTIBLE POWER SYSTEM, BY CONSIDERING DECREASE IN CAPACITY CAUSED DUE TO WEAR-OUT OF BATTERY

摘要

PURPOSE: A method is provided to reduce error of calculation by considering decrease in capacity caused due to wear-out of a battery in Peukert's equation. CONSTITUTION: A method comprises a step of inputting constants n and k of Peukert's equation into a system controller, in consideration of elapse of battery time, by consuming the constants n and k as function n=f(R) and K=f(R), and calculating state of charge of a battery. The state of charge is calculated by using a cubic equation or a quadratic equation Y=a+bX+cX¬2+dX¬3, wherein Y is the value of n, and X is the battery time. The state of charge is calculated by using an exponential function having a formula Y=axexp(X/b)+c, wherein Y is the value of k, and X is the battery time.