SOC Correcting System Having Multiple Packs in Parallel

• US 20140002095A1
• Filed: 02/17/2012
• Published: 01/02/2014
• Est. Priority Date: 02/22/2011
• Status: Active Grant

• Current Assignee: SK On Company Limited (SK Innovation Company Limited)
• Original Assignee: SK Innovation Company Limited
• Inventors: Lim, Jae Hwan
• Granted Patent: US 9,234,944 B2
• Time in Patent Office: Days
• US Class Current: 324/434
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0038 relating to sensors
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: G01R 31/3835 involving only voltage measurements
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

Provided is a SOC correcting system in a parallel structure of multiple packs that a plurality of sub-packs having serially connected cells are connected in parallel, the system including of: sub BMSs connected to each of the sub packs to calculate each SOC of the sub-packs; and a main BMS connected to each of the sub BMSs to collect the SOCs calculated in each of the sub BMSs and transmit a final SOC to a vehicle controller, wherein when an average SOC to each SOC of the sub-packs is less than 50%, the main BMS determines a minimum value among the SOCs of the sub-packs as a final SOC, and when the average SOC to each SOC of the sub-packs is 50% or more, the main BMS determines a maximum value among the SOCs of the sub-packs as a final SOC.

Claims

1. A State Of Charge (SOC) correcting system in a parallel structure of multiple packs that a plurality of sub-packs having serially connected cells are connected in parallel, the system comprising of:

sub Battery Management Systems (BMSs) connected to each of the sub-packs to calculate each SOC of the sub-packs; and

a main BMS connected to each of the sub BMSs to collect the SOCs calculated in each of the sub BMSs and transmit a final SOC to a vehicle controller,

wherein when the average SOC to each SOC of the sub-packs is less than 50%, the main BMS determines a minimum value among the SOCs of the sub-packs as a final SOC, and

when an average SOC to each SOC of the sub-packs is 50% or more, the main BMS determines a maximum value among the SOCs of the sub-packs as a final SOC.

2. The SOC correcting system of claim 1, wherein when a cell voltage sensed by a plurality of voltage sensors included in each of the sub-packs is 0.5V or less, the sub BMSs determine that there is a sensing error in the corresponding voltage sensor.

3. The SOC correcting system of claim 1, wherein the sub BMSs sum up cell voltages sensed by the voltage sensor, which does not have sensing error, among the voltage sensors included in each of the sub-packs, divide the sum of the cell voltages by the number of voltage sensors, which do not have sensing error, to obtain one cell voltage, and calculate the SOC of the corresponding sub-packs based on the calculation.

4. The SOC correcting system of claim 1, wherein when a cell voltage sensed by the voltage sensors included in each of the sub-packs is 0.5V or less, the sub BMSs transmit a check code to the main BMS and the main BMS transmits a check code to the vehicle controller.

5. The SOC correcting system of claim 1, wherein the main BMS applies a correction rate as a change rate of the final SOC to the final SOC to correct that the final SOC is remarkably changed.