Apparatus and method for determining the current state of charge of a battery by monitoring battery voltage increases above and decreases below a threshold
First Claim
1. An apparatus for determining a current state of charge of a battery having a battery voltage, comprising:
- a battery signal developer having an input for receiving the battery voltage, the battery signal developer for developing a battery signal having a magnitude corresponding to the battery voltage;
a threshold developer having an input for receiving an integration result signal based on an integration value having a magnitude representative of the current state of charge of the battery, the threshold developer for developing a threshold signal having a magnitude based on the magnitude of the integration value;
a comparator having inputs for receiving the battery signal and the threshold signal, the comparator for providing a first comparison signal when the magnitude of the battery signal is greater than the magnitude of the threshold signal and a second comparison signal when the magnitude of the battery signal is less than the magnitude of the threshold signal;
a bi-directional integrating device for accumulating the integration value, the integrating device having an input for receiving a comparison result signal based on the first comparison signal and the second comparison signal, the integrating device for adjusting the integration value in a first direction when the first comparison signal is being provided by the comparator to reflect an increase in the current state of charge of the battery, the integrating device for adjusting the integration value in a second direction opposite from the first direction when the second comparison signal is being provided by the comparator to reflect a decrease in the current state of charge of the battery;
an initialize detect device for generating an initialize signal when the battery is initially connected to the apparatus; and
a frequency generator having an input for receiving the initialize signal, the frequency generator for providing a frequency signal having a first predetermined frequency rate for a period of time beginning when the initialize signal is received and a second predetermined frequency rate thereafter, the first frequency rate being higher than the second frequency rate, the integrating device adjusting the integration value according to the frequency signal.
1 Assignment
0 Petitions
Accused Products
Abstract
An apparatus and method for determining a current state of charge of a battery are disclosed. The apparatus includes a battery signal developer, a threshold developer, a comparator, and a bi-directional integrating device. The battery signal developer receives a battery voltage and develops a corresponding battery signal. The threshold developer receives an integration result signal based on an integration value representative of the current state of charge of the battery, and develops a threshold signal based on the integration value. The comparator provides first and second comparison signals, respectively, when the battery signal magnitude is greater than and less than the threshold signal magnitude. The integrating device accumulates the integration value and receives a comparison result signal based on the first and second comparison signals. The integrating device adjusts the integration value in first and second opposite directions, respectively, when the first and second comparison signals are being provided by the comparator to reflect both increases and decreases in the current state of charge of the battery.
-
Citations
18 Claims
-
1. An apparatus for determining a current state of charge of a battery having a battery voltage, comprising:
-
a battery signal developer having an input for receiving the battery voltage, the battery signal developer for developing a battery signal having a magnitude corresponding to the battery voltage; a threshold developer having an input for receiving an integration result signal based on an integration value having a magnitude representative of the current state of charge of the battery, the threshold developer for developing a threshold signal having a magnitude based on the magnitude of the integration value; a comparator having inputs for receiving the battery signal and the threshold signal, the comparator for providing a first comparison signal when the magnitude of the battery signal is greater than the magnitude of the threshold signal and a second comparison signal when the magnitude of the battery signal is less than the magnitude of the threshold signal; a bi-directional integrating device for accumulating the integration value, the integrating device having an input for receiving a comparison result signal based on the first comparison signal and the second comparison signal, the integrating device for adjusting the integration value in a first direction when the first comparison signal is being provided by the comparator to reflect an increase in the current state of charge of the battery, the integrating device for adjusting the integration value in a second direction opposite from the first direction when the second comparison signal is being provided by the comparator to reflect a decrease in the current state of charge of the battery; an initialize detect device for generating an initialize signal when the battery is initially connected to the apparatus; and a frequency generator having an input for receiving the initialize signal, the frequency generator for providing a frequency signal having a first predetermined frequency rate for a period of time beginning when the initialize signal is received and a second predetermined frequency rate thereafter, the first frequency rate being higher than the second frequency rate, the integrating device adjusting the integration value according to the frequency signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method for determining a current state of charge of a battery having a battery voltage, the method comprising the steps of:
-
developing a battery signal having a magnitude corresponding to the battery voltage; developing a threshold signal having a magnitude based on an integration value having a magnitude representative of the current state of charge of the battery; providing a first comparison signal when the magnitude of the battery signal is greater than the magnitude of the threshold signal; providing a second comparison signal when the magnitude of the battery signal is less than the magnitude of the threshold signal; adjusting the integration value in a first direction when the first comparison signal is being provided to reflect an increase in the current state of charge of the battery; adjusting the integration value in a second direction opposite from the first direction when the second comparison signal is being provided to reflect a decrease in the current state of charge of the battery; generating an initialize signal when the battery is initially connected to an apparatus for determining the current state of charge; and providing a frequency signal having a first predetermined frequency rate for a period of time beginning when the initialize signal is generated and a second predetermined frequency rate thereafter, the first frequency rate being higher than the second frequency rate, the integration value being adjusted according to the frequency signal. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
Specification