초록 ▼

A reliable technique of predicting the available reserve time remaining to a selected end voltage of a discharging battery is based on an adaptive state-of-charge algorithm that is active in real time to respond to changing conditions of a battery system. The adaptive state-of-charge algorithm is ba

A reliable technique of predicting the available reserve time remaining to a selected end voltage of a discharging battery is based on an adaptive state-of-charge algorithm that is active in real time to respond to changing conditions of a battery system. The adaptive state-of-charge algorithm is based on measured discharge characteristics of the battery whose reserve time is to be predicted which have been reduced to two parameters plotted as a single curve with a linear and an exponential region. These discharge characteristics are combined with dynamic parameters of the battery system which are monitored and processed in real time to provide a continuous evaluation and reevaluation of the reserve time remaining under changing conditions. As the discharge proceeds there is a continual improvement in the prediction of reserve time available. This predictive feature embodying the principles of the invention is included in a stored program controller for a battery plant in a central office in the illustrative embodiment of the invention disclosed herein. In such applications it is highly desirable to be able to predict the available reserve time of a discharging battery until a final end voltage level is reached.

대표청구항 ▼

A method of predicting the time remaining of a battery discharge until an end voltage is attained; comprising the steps of characterizing the discharge behavior of a discharging battery with a discharge curve having a locus invariant with respect to a magnitude of the discharge current and being var

A method of predicting the time remaining of a battery discharge until an end voltage is attained; comprising the steps of characterizing the discharge behavior of a discharging battery with a discharge curve having a locus invariant with respect to a magnitude of the discharge current and being variant with respect to a fraction of available charge to an end voltage charge and to a function of a difference between a plateau voltage and a present voltage of the discharging battery, measuring the plateau voltage of the discharging battery, measuring a present voltage of the discharging battery to locate a point on the discharge curve, using the discharge curve for determining the fraction of available charge to an end voltage charge and expressing the fraction as a dimensionless time ratio, converting the dimensionless time ratio to a time remaining until the discharging battery reaches a selected end voltage.