Battery voltage detector

• US 6,462,510 B1
• Filed: 03/09/2001
• Issued: 10/08/2002
• Est. Priority Date: 09/11/1998
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Torii, Yuji, Tamesue, Kazuhiko, Takada, Masahiro
• Primary Examiner(s): Tso, Edward H.
• Assistant Examiner(s): TIBBITS, PIA FLORENCE
• Application Number:
  US09/786,342
• Time in Patent Office: 578 Days
• Field of Search: 320/116, 320/139
• US Class Current: 320/116
• CPC Class Codes: B60L 53/665 Methods related to measuring, billing or payment
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/167 Systems integrating technologies related to power network operation and communication or information technologies for supporting the interoperability of electric or hybrid vehicles, i.e. smartgrids as interface for battery charging of electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: Y04S 30/14 Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing

Abstract

A battery power source device is composed of a plurality of battery modules, in which each battery module includes a number of serially connected cells. A voltage detection circuit is associated with each battery module. Each voltage detection circuit includes a differential amplifier that detects a voltage across end terminals of the associated battery module, and the detected voltage is digitized and output through a photo-coupler to a controller. The differential amplifier is connected to the battery module through photo-relays, which are closed in response to an open/close control signal only during a voltage detection operation, so that leak currents are eliminated. The differential amplifier and an associated A/D converter are provided with operating power obtained by transforming the voltage of the battery module with regulators, whereby noise effects are eliminated.

Claims

1. A battery voltage detecting device provided in a battery power source device used as a drive power source of an electric motor for a vehicle, wherein a plurality of rechargeable battery cells are serially connected in a battery pack, the cells being divided into a plurality of groups each including a predetermined number of serially connected cells to form a plurality of battery modules, the battery pack being mounted on the vehicle with its ground potential being electrically insulated from ground potential of an electric circuit system of a controller for the vehicle, the battery voltage detecting device comprising:

a plurality of voltage detection circuits, respectively provided to the plurality of battery modules, each of the plurality of voltage detection circuits comprising;

a differential detecting system that detects a voltage across end terminals of at least one battery module,

open/close systems which open and close and that connect and disconnect the differential detecting system to and from the end terminals of the battery module,

an A/D converter for digitizing the detected voltage of the battery module output from the differential detecting system,

an output data transmission system that transmits data output from the A/D converter to the electric circuit system of the controller for the vehicle electrically insulated therefrom, and

an open/close signal transmission system that transmits an open/close signal output from the electric circuit system of the controller for the vehicle to the open/close systems electrically insulated therefrom; and

an operating power source electrically insulated from the ground potential of the electric circuit system of the controller for the vehicle for providing each of the voltage detection circuits separately with operating power.

2. A battery voltage detecting device provided in a battery power source device used as a drive power source of an electric motor for a vehicle, wherein a plurality of rechargeable battery cells are serially connected to constitute a battery pack, the cells being divided into a plurality of groups each including a predetermined number of serially connected cells to form a plurality of battery modules, the battery pack being mounted on the vehicle with its ground potential being electrically insulated from ground potential of an electric circuit system of a controller for the vehicle, the battery voltage detecting device comprising:

a plurality of voltage detection circuits, each provided to a unit of a plurality of battery modules, each of the plurality of voltage detection circuits comprising;

a differential detecting system connected through a detection switching circuit to the unit of the plurality of battery modules and that detects a voltage across end terminals of a selected one of the plurality of battery modules,

an A/D converted for digitizing the detected voltage of the battery module output from the differential detecting system,

an output data transmission system that transmits data output from the A/D converted to the electric system of the controller for the vehicle electrically insulated therefrom,

an open/close signal transmission means for transmitting an open/close signal output from the electric circuit system of the controller for the vehicle to the detection switching circuit electrically insulated therefrom, wherein

said detection switching circuit comprising;

a plurality of open/close systems which open and close that respectively connect and disconnect the differential detecting system to and from the respective end terminals of the plurality of battery modules, and

an open/close control system that separately opens and closes a selected one of the plurality of the open/close system in accordance with the open/close control signal input from the open/close signal transmission system, whereby the selected one of open/close systems is closed to connect the differential detecting system to the end terminals of the selected one of the battery modules; and

an operating power source electrically insulated from the ground potential of the electric circuit system of the controller for the vehicle for providing each of the voltage detection circuits separately with operating power.

3. A battery voltage detecting device provided in a battery power source device used as a drive power source of an electric motor for a vehicle, wherein a plurality of rechargeable battery cells are serially connected to constitute a battery pack, the cells being divided into a plurality of groups each including a predetermined number of serially connected cells to form a plurality of battery modules, the battery pack being mounted on the vehicle with its ground potential being electrically insulated from ground potential of an electric circuit system of a controller for the vehicle, the battery voltage detecting device comprising:

a plurality of voltage detection circuits, respectively provided to the plurality of battery modules each of the plurality of voltage detection circuits comprising;

a differential detecting system that detects a voltage across end terminals of a battery module,

a first voltage conversion system that supplies the differential detecting system with operating power by transforming the voltage of the battery module,

an A/D converter for digitizing the detected voltage of the battery module output from the differential detecting system,

a second voltage conversion system that supplies the A/D converter with operating power by transforming the voltage of the battery module, and

an output data transmission system that transmits data output from the A/D converter to the electric circuit system of the controller for the vehicle electrically insulated therefrom.

4. A battery voltage detecting device provided in a battery power source device used as a drive power source of an electric motor for a vehicle, wherein a plurality of rechargeable battery cells are serially connected to constitute a battery pack, the cells being divided into a plurality of groups each including a predetermined number of serially connected cells to form a plurality of battery modules, the battery pack being mounted on the vehicle with its ground potential being electrically insulated from ground potential of an electric circuit system of a controller for the vehicle, the battery voltage detecting device comprising:

a plurality of voltage detection circuits, respectively provided to the plurality of battery modules, each of the plurality of voltage detection circuits comprising;

a differential detecting system that detects a voltage across end terminals of a battery module,

open/close systems which open and close and that connect and disconnect the differential detecting system to and from the end terminals of the battery module,

a first voltage conversion system that supplies the differential detecting system with operating power by transforming the voltage of the battery module,

an A/D converter for digitizing the detected voltage of the battery module output from the differential detecting system,

a second voltage conversion system that supplies the AID converter with operating power by transforming the voltage of the battery module,

an output data transmission system that transmits data output from the A/D converter to the electric circuit system of the controller for the vehicle electrically insulated therefrom, and

an open/close signal transmission system that transmits an open/close signal, output from the electric circuit system of the controller for the vehicle, to the open/close systems electrically insulated therefrom.

5. A battery voltage detecting device provided in a battery power source device used as a drive power source of an electric motor for a vehicle, wherein a plurality of rechargeable battery cells are serially connected to constitute a battery pack, the cells being divided into a plurality of groups each including a predetermined number of serially connected cells to form a plurality of battery modules, the battery pack being mounted on the vehicle with its ground potential being electrically insulated from ground potential of an electric circuit system of a controller for the vehicle, the battery voltage detecting device comprising:

a plurality of voltage detection circuits, each provided to a unit of a plurality of battery modules, each of the plurality of voltage detection circuits including

a differential detecting system connected through a detection switching circuit to the unit of the plurality of battery modules and that detects a voltage across end terminals of a selected one of the plurality of battery modules,

a first voltage conversion system that supplies the differential detecting system with operating power by transforming the voltage of the battery module,

an A/D converter for digitizing the detected voltage of the battery module output from the differential detecting system;

a second voltage conversion system that supplies the A/D converter with operating power by transforming the voltage of the battery module;

an output data transmission system that transmits data output from the A/D converter to the electric circuit system of the controller for the vehicle electrically insulated therefrom;

an open/close signal transmission system that transmits an open/close signal, output from the electric circuit system of the controller for the vehicle, to the detection switching circuit electrically insulated therefrom, wherein

said detection switching circuit comprises;

a plurality of open/close systems which open and close and that respectively connect and disconnect the differential detecting system to and from the respective end terminals of the plurality of battery modules, and

an open/close control system that separately opens and closes a selected one of the plurality of open/close systems in accordance with the open/close control signal input from the open/close signal transmission system, whereby the selected one of open/close systems is closed to connect the differential detecting system to the end terminals of the selected one of the battery modules.