Means for estimating charged state of battery and method for estimating degraded state of battery
First Claim
1. Means for estimating a state of charge of a battery, comprising a battery model for determining a pseudo-SOC (state of charge) as a temporary value representative of the SOC of the battery and estimating a voltage of the battery by considering the pseudo-SOC and a change in state of the battery, whereby a real SOC is estimated by correcting the pseudo-SOC so that the estimated voltage of the battery is equal to an actually measured voltage of the battery,wherein the battery model includes:
- pseudo-SOC estimating means for determining the pseudo-SOC from charging/discharging current of the battery, electromotive force estimating means for estimating the voltage of the battery in accordance with the pseudo-SOC output from the pseudo-SOC estimating means, voltage change estimating means for estimating a change in the voltage of the battery caused by internal resistance, and dynamic voltage change estimating means for estimating a change in the voltage of the battery based on a change in the charging/discharging current of the battery, wherein the voltage of the battery is estimated from the sum of output values of the electromotive force estimating means, the voltage change estimating means, and the dynamic voltage change estimating means.
1 Assignment
0 Petitions
Accused Products
Abstract
Means for estimating the charged state of a battery, capable of accurately estimating an SOC even though the battery repeats charging/discharging in short cycles. The charging/discharging current Ib measured by current sensing means (10) is integrated, and pseudo-SOC estimating means estimates a pseudo-SOC. Electromotive force estimating means (16) estimates the open voltage Voc from the pseudo-SOC. Voltage change estimating means (18) estimates the voltage change Vr due to the internal resistance from the charging/discharging current Ib. Dynamic voltage change estimating means (20) estimates the voltage change Vdyn due to the change of the charging/discharging current. An adder (22) adds the Voc, Vr, and Vdyn to calculate an estimated voltage Vest of the battery. SOC correction calculating means (26) calculates the correction of the SOC for equalizing the estimated voltage Vest to the measured voltage Vmes measured by voltage sensing means (12), and an adder (28) adds the correction to the pseudo-SOC to estimate the SOC of the battery.
-
Citations
12 Claims
-
1. Means for estimating a state of charge of a battery, comprising a battery model for determining a pseudo-SOC (state of charge) as a temporary value representative of the SOC of the battery and estimating a voltage of the battery by considering the pseudo-SOC and a change in state of the battery, whereby a real SOC is estimated by correcting the pseudo-SOC so that the estimated voltage of the battery is equal to an actually measured voltage of the battery,
wherein the battery model includes: -
pseudo-SOC estimating means for determining the pseudo-SOC from charging/discharging current of the battery, electromotive force estimating means for estimating the voltage of the battery in accordance with the pseudo-SOC output from the pseudo-SOC estimating means, voltage change estimating means for estimating a change in the voltage of the battery caused by internal resistance, and dynamic voltage change estimating means for estimating a change in the voltage of the battery based on a change in the charging/discharging current of the battery, wherein the voltage of the battery is estimated from the sum of output values of the electromotive force estimating means, the voltage change estimating means, and the dynamic voltage change estimating means. - View Dependent Claims (2, 3, 4, 5, 8, 9, 10, 11, 12)
-
-
6. A method for estimating the degraded state of battery, comprising the steps of:
-
measuring charging/discharging current and a voltage of a battery;
determining a pseudo-SOC (state of charge) of the battery as a value representative of estimated SOC of the battery from an integrated value of the charging/discharging current;
estimating an open voltage Voc of the battery from the pseudo-SOC;
estimating a dynamic voltage change Vdyn of the battery based on a change in the charging/discharging current of the battery;
determining a difference Vr between the sum of the open voltage Voc and the dynamic voltage change Vdyn, and the measured voltage Vmes of the battery according to the expression - View Dependent Claims (7)
-
Specification
-
- Resources
-
Current AssigneeToyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
-
Original AssigneeToyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
-
InventorsKikuchi, Yoshiaki, Watanabe, Nobuo, Kuroda, Yukio
-
Primary Examiner(s)Tso, Edward H.
-
Application NumberUS09/701,067Time in Patent Office284 DaysField of Search320/132, 320/149, 320/DIG.21, 324/426, 324/427, 324/433, 340/635, 340/636US Class Current320/132CPC Class CodesG01R 31/374 with means for correcting t...G01R 31/389 Measuring internal impedanc...
