Power source monitoring arrangement and method having low power consumption

• US 5,907,238 A
• Filed: 12/12/1997
• Issued: 05/25/1999
• Est. Priority Date: 12/16/1996
• Status: Expired due to Term

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: TRW Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Owerko, John R., Theodorou, Alexander N., Eichenseer, John C.
• Primary Examiner(s): BERHANE, ADOLF D
• Application Number:
  US08/990,111
• Time in Patent Office: 529 Days
• Field of Search: 323/349, 320/135, 320/127, 320/153, 320/136
• US Class Current: 323/349
• CPC Class Codes: H02J 9/005 using a power saving mode for copiers G03G15/5004
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y04S 20/20 End-user application control systems

Abstract

An electronic circuit and system (1) incorporating a battery system (30), power-discharge sensing circuitry (40) and sleep circuitry (10) all in electrical communication with each other. The sleep circuitry (10) detects the presence or absence of an external load on the battery system (30) by sensing changes in voltage across the battery'"'"'s protection diode (D3). When no external load is present, the sleep circuitry (10) controls the power-discharge sensing circuitry (40) in an extremely low current mode (e.g., current is consumed by sleep circuitry (10), but no power supplied to power-discharge sensing circuitry (40)). This mode is also referred to as a sleep mode. Upon detection of a small voltage drop on the battery'"'"'s protection diode (D3) caused by a power-consuming load on the battery, the sleep circuitry (10) supplies power to the power-discharge sensing circuitry (40). When the power-discharge sensing circuitry (40) is thus activated, the amount of power removed from the battery system (30) can then be monitored. When the load is removed, the power-discharge sensing circuitry (40) is again placed into the sleep mode.

Claims

1. An electronic circuit and battery system for reducing the need to continuously monitor the amount of power remaining in a power source, the system comprising:

(a) a battery system;

(b) a sleep circuit in electrical connection with the battery system, the sleep circuit including substantially similar transistors, and a bias diode which is selected to have a substantially similar temperature co-efficient as that of a protection diode within the system, in electrical connection with substantially similar resistors to obtain circuit stability and temperature tracking over a wide range of temperatures and voltages from the battery system; and

(c) a power-discharge sensing circuit electrically coupled to the sleep circuit and battery system, the sleep circuit controlling the power-discharge sensing circuit to monitor the power remaining in the battery system.

2. The electronic circuit and battery system of claim 1, wherein the sleep circuit includes a diode voltage sensor electrically coupled to the battery system, a quasi-threshold comparator circuit electrically coupled to the diode voltage sensor, and an inverter/load driver circuit electrically coupled to the quasi-threshold comparator circuit and the power-discharge sensing circuit.

3. The electronic circuit and battery system of claim 1, wherein the power-discharge sensing circuit includes a sensing resistor, an integrator circuit, a discharge circuit, a comparator/one-shot circuit and a counter/display unit, all in electrical communication with each other.

4. A battery capacity measurement system adapted to operate over a wide range of temperatures and battery voltages, comprising:

(a) a battery system having at least one battery cell in electrical connection with a protection diode and a fuse;

(b) a power-discharge sensing circuit in electrical communication with the battery system; and

(c) a sleep circuit attached to the battery system, the sleep circuit electrically monitoring the battery system to control the power-discharge sensing circuit to reduce the amount of power consumed by the power-discharge sensing circuit regardless of the existence of a load on the battery system.

5. A micro-power sleep circuit in electrical connection with a battery system and a power-discharge sensing circuit, the sleep circuit adapted to monitor voltage changes across existing protection diode of the battery system to control the power-discharge sensing circuit and thereby significantly diminish the amount of power required to operate the power-discharge sensing circuit.

6. A device for monitoring the amount of power remaining in a power source, including a battery system having at least one battery in electrical connection with a protection diode and a fuse, the improvement comprising:

(a) a micro-power sleep circuit electrically monitoring the battery system; and

(b) a power-discharge sensing circuit in electrical contact with the battery system and the sleep circuit, the power-discharge circuit controlled by the sleep circuit whenever the sleep circuit detects a voltage change in the battery system.

7. A device for monitoring the amount of power remaining in a power source, including a battery system electrically attached to a continuously powered state-of-charge indicator, the improvement comprising a micro-power sleep circuit electrically attached to the battery system and electrically controlling operation of the state-of-charge indicator, the sleep circuit designed to monitor voltage changes across an existing protection diode of the battery system to significantly reduce the need to continuously monitor the amount of power remaining in the power source.

8. A device for monitoring an amount of electric power in a power source, said apparatus comprising:

means for measuring power provided by the power source;

means for counting units of the measured power;

means for detecting whether an external power-consuming load is connected to the power source; and

means for supplying operating power to said means for measuring only when said means for detecting detects the power-consuming load.

9. A device as set forth in claim 8, wherein said means for measuring includes an integrator circuit.

10. A device as set forth in claim 8, wherein the power source has a diode, and said means for detecting includes a diode voltage sensor for sensing voltage across the diode.

11. A device as set forth in claim 8, wherein said means for detecting includes a comparator circuit, said diode voltage sensor includes means for sensing a voltage drop across the diode resulting from the power-consuming load, said diode voltage sensor includes means for outputting a trigger signal to said comparator circuit, and said comparator circuit includes means for outputting a control signal to said means for supplying in response to said trigger signal from said diode voltage sensor.

12. A device as set forth in claim 8, wherein said means for supplying includes an inverter/load driver circuit.

13. A method for measuring battery capacity over a predetermined range of temperatures and battery voltages, comprising the steps of:

(a) providing a battery system having at least one battery in electrical connection with a protection diode and a fuse;

(b) electrically attaching a power-discharge sensing circuit to the battery system, the power-discharge sensing circuit adapted to monitor the amount of power dissipated by a battery; and

(c) electrically attaching a sleep circuit between the power-discharge sensing circuit and the battery system, the sleep circuit monitoring the battery system to control the power-discharge sensing circuit to reduce the amount of power consumed by the power-discharge sensing circuit regardless of the existence of a load on the battery system.

14. A method for controlling the amount of power required to continuously monitor a power-discharge sensing circuit attached to a battery system, comprising the steps of:

(a) electrically attaching a sleep circuit between the power-discharge sensing circuit and the battery system; and

(b) allowing the sleep circuit to continuously monitor voltage changes across an existing protection diode of the battery system and control the power-discharge sensing circuit to significantly diminish the amount of power from the battery system required by the power-discharge sensing circuit to operate.