Battery monitoring device

• US 9,448,287 B2
• Filed: 07/30/2012
• Issued: 09/20/2016
• Est. Priority Date: 07/29/2011
• Status: Active Grant

• Current Assignee: Yokogawa Electric Corporation
• Original Assignee: Yokogawa Electric Corporation
• Inventors: Okada, Syuhei, Yoshitake, Satoshi
• Primary Examiner(s): Ali, Mohammad
• Assistant Examiner(s): Azad, Md
• Application Number:
  US13/561,162
• Publication Number:
  US 20130030596A1
• Time in Patent Office: 1,513 Days
• Field of Search: 702/63, 702/65, 320/119, 320/129, 320/136, 320/139, 324/427, 324/428, 324/430, 324/432, 324/434, 340/136, 340/636, 700/297
• US Class Current: 1/1
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables

Abstract

A battery monitoring device for real-time measurement and monitoring of a battery module driving an actual load and having a plurality battery cells connected together in series, has a plurality of power and impedance calculators provided for the respective battery cells, and configured to receive voltage signals and current signals from the battery cells, respectively and to measure instantaneous power values and internal impedance characteristics of the battery cells, respectively, and a battery module state manager configured to receive output data of the power and impedance calculators via an internal bus.

Claims

1. A battery monitoring device for real-time measurement and monitoring of a battery module driving an actual load and having a plurality of battery cells connected together in series, comprising:

a plurality of power and impedance calculators each provided for one of the plurality of battery cells, and configured to receive voltage signals and current signals from the plurality of battery cells, respectively and to measure instantaneous power values and internal impedance characteristics of the plurality of battery cells, respectively;

a battery module state manager configured to receive output data of the plurality of power and impedance calculators via an internal bus,

a load state monitor configured to monitor a state of load of the battery module, and to input a detection signal to the plurality of power and impedance calculators and the battery module state manager; and

an accelerator work monitor configured to monitor movement of the accelerator which is part of a vehicle driving system as a load device of the battery module, and to supply the resulting detection signal to the plurality of power and impedance calculators and the battery module state manager,

wherein, based on a detection signal of variation of at least one of an accelerator, current, voltage, or a power waveform, a condition occurs, the condition comprising extraction of at least one of the current, voltage, or power waveform, and setting at least one of a sampling clock frequency, correction of measurement data, or a frequency analysis,

wherein each of the plurality of power and impedance calculators is configured to acquire measurement data at such a time resolution and based on a time span that optimum estimation of a time constant of reaction occurring in a battery cell is enabled according to the reaction time constant, and to estimate constants of an equivalent circuit that are considered to govern the time constant using the acquired measurement data.

2. The battery monitoring device according to claim 1, wherein each of the plurality of power and impedance calculators is configured to perform discrete Fourier transformation or fast Fourier transformation, and to estimate constants of an equivalent circuit that exhibits an internal impedance characteristic of the associated battery cell in a desired frequency domain on the basis of results of the discrete Fourier transformation or fast Fourier transformation.

3. The battery monitoring device according to claim 1, wherein the power and impedance calculators are configured to receive pieces of temperature information of the plurality of battery cells, respectively.

4. The battery monitoring device according to claim 1, further comprising:

a pseudo-load device connected to the actual load in parallel and configured to generate a waveform including high-frequency components.

5. The battery monitoring device according to claim 1, further comprising:

a load control unit configured to drive and control the actual load according to a load program.

6. The battery monitoring device according to claim 1, wherein one of the plurality of power and impedance calculators comprises an accelerator variation amount detector, a clock controller, and a variable clock generator.

7. The battery monitoring device according to claim 1, wherein one of the plurality of power and impedance calculators comprises a power measuring unit and a power information storage unit.

8. The battery monitoring device according to claim 1, wherein the data from the battery monitoring device comprises trend data of instantaneous power of each of the battery cells.