CELL SITE POWER GENERATION

• US 20100009724A1
• Filed: 07/10/2008
• Published: 01/14/2010
• Est. Priority Date: 07/10/2008
• Status: Active Grant

• Current Assignee: T-Mobile USA, Inc. (Deutsche Telekom AG)
• Original Assignee: T-Mobile USA, Inc. (Deutsche Telekom AG)
• Inventors: Fischer, Steve
• Granted Patent: US 8,729,732 B2
• Time in Patent Office: Days
• US Class Current: 455/573
• CPC Class Codes: H02J 1/10 Parallel operation of dc sources
• CPC Class Codes: H02J 9/061 for DC powered loads
• CPC Class Codes: H02J 9/066 characterised by the use of dynamo-electric machines H02J9/08 takes precedence
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 52/0206 in access points, e.g. base stations access point devices per se H04W88/08
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A system, apparatus, method, and manufacture for generating backup power in a wireless communications system such as a wireless communications service base station. The system includes a communications interface, a primary power interface, a generator, rectifiers, and a battery circuit. During normal operation, the communications interface is powered from the primary power interface. During a power outage, the communications interface is powered from either the generator or the battery circuit. The generator is cycled on and off during power outages to charge the battery circuit while conserving fuel. To decrease rectification loss, rectifiers are run near full load while rectifying the generator output.

Claims

1. A system for generating power, comprising:

a communications interface configured to communicatively couple a wireless interface to a telecommunications back-haul;

multiple power sources, including;

a primary power interface configured to provide power from a primary power source to the communications interface;

a back-up generator, wherein the back-up generator is configured to be selectively enabled to generate power and to provide generated power to the communications interface, to a battery circuit, or both; and

the battery circuit, wherein the battery circuit is configured to selectively provide power to the communications interface;

a rectifier and switch circuit configured to selectively switch power between the multiple power sources and from the multiple power sources to the communications interface; and

a power controller configured to individually enable and disable multiple rectifiers based, at least in part, on an availability status of the primary power source; and

wherein the power controller is configured to control the switching of the rectifier and switch circuit and to enable and disable the back-up generator.

2. The system of claim 1, wherein the power controller is further configured to enable and disable the back-up generator based on a sensed voltage of the battery circuit and on an operational status of the telecommunications back-haul.

3. The system of claim 1, wherein the rectifier and switch circuit includes:

multiple rectifiers each configured to selectively rectify power from the primary power interface and/or from the back-up generator.

4. The system of claim 1, wherein the battery circuit includes a string of serially connected absorbed glass mat lead-acid batteries, and wherein the generator is at least one of a gasoline generator, a diesel generator, a propane generator, a natural gas generator, a methanol generator, or an ethanol generator.

5. The system of claim 1, wherein the battery circuit includes:

a first battery having at least a positive terminal and a negative terminal;

a second battery having at least a positive terminal and a negative terminal;

a first jumper configured to connect the negative terminal of the first battery to the positive terminal of the second battery; and

an opto-isolator circuit configured to sense a voltage potential between the negative terminal of the first battery and the negative terminal of the second battery or between the positive terminal of the first battery and the positive terminal of the second battery, and wherein the power controller is further configured to detect a battery circuit failure based, at least in part, on a rate of change of the sensed voltage.

6. The system of claim 1, wherein the power controller is further configured to enable the back-up generator if a sensed voltage of the battery circuit represents that the battery circuit has less than approximately a twenty percent charge, and to disable the back-up generator if the sensed voltage of the battery circuit represents that the battery circuit has more than approximately an eighty-two percent charge.

7. An apparatus for providing generated power to a wireless communications system, comprising:

a rectifier and switch circuit configured to selectively switch power between multiple power sources and from the multiple power sources to a system interface, wherein the rectifier and switch circuit includes;

multiple rectifiers each configured to selectively rectify power from at least two power sources of the multiple power sources; and

a power controller configured to individually enable and disable each of the multiple rectifiers based, at least in part, on an availability status of at least one power source of the multiple power sources; and

further configured to control the switching of the rectifier and switch circuit.

8. The apparatus of claim 7, further comprising:

a system interface; and

multiple power sources, including;

a primary power interface configured to provide power from a primary power source to the system interface;

a generator; and

a battery circuit, wherein the generator is configured to be selectively enabled to generate power and to provide generated power to the system interface, to the battery circuit, or both; and

wherein the battery circuit is configured to selectively provide power to the system interface; and

wherein the multiple rectifiers are each further configured to selectively rectify power from the primary power interface and/or from the generator;

wherein the power controller is further configured to individually enable or disable each of the multiple rectifiers based, at least in part, on an availability status of the primary power source; and

wherein the power controller is further configured to enable and disable the generator.

9. The apparatus of claim 7, wherein the battery circuit includes a string of serially connected absorbed glass mat lead-acid batteries.

10. The apparatus of claim 7, further comprising:

a management interface configured to communicate operational data from at least one of the battery circuit, the generator, the primary power interface, or the rectifier and switch circuit to a remote system.

11. The apparatus of claim 7, wherein the generator is at least one of a gasoline generator, a diesel generator, a propane generator, a natural gas generator, a methanol generator, or an ethanol generator;

and wherein the generator is at least one of an air-cooled generator or a liquid-cooled generator.

12. The apparatus of claim 7, wherein the power controller is further configured to selectively enable and disable the generator based, at least in part, on a sensed voltage of the battery circuit.

13. The apparatus of claim 7, wherein the power controller is further configured to selectively enable and disable the generator based, at least in part, on a received operational status.

14. The apparatus of claim 7, wherein the power controller is further configured to enable the generator if a sensed voltage of the battery circuit represents that the battery circuit has less than approximately a twenty percent charge, and to disable the generator if the sensed voltage of the battery circuit represents that the battery circuit has more than approximately an eighty-two percent charge.

15. The apparatus of claim 7, wherein the battery circuit includes:

a first battery having at least a first terminal and a second terminal;

a second battery having at least a first terminal and a second terminal;

a first jumper configured to connect the second terminal of the first battery to the first terminal of the second battery; and

a monitoring circuit configured to sense a voltage potential between the second terminal of the first battery and the second terminal of the second battery, and wherein the power controller is further configured to detect a battery circuit failure based, at least in part, on a rate of change of the sensed voltage.

16. The apparatus of claim 7, wherein the battery circuit includes:

a first battery having at least a first terminal and a second terminal;

a second battery having at least a first terminal and a second terminal;

a first jumper configured to connect the second terminal of the first battery to the first terminal of the second battery; and

an opto-isolator circuit configured to sense a voltage potential between the second terminal of the first battery and the second terminal of the second battery, and wherein the power controller is further configured to detect a battery circuit failure based, at least in part, on a rate of change of the sensed voltage.

17. The apparatus of claim 7, wherein the power controller further includes a watchdog circuit and wherein the power controller is further configured to enable or disable the generator based, in part, on an output of the watchdog circuit.

18. A method of providing generated power to a wireless communications cell site having a transceiver and associated telecommunications components, the method comprising:

receiving power from a primary power source to power the cell site;

while receiving power from the primary power source, employing a first number of rectifiers to rectify the power received from the primary power source;

determining an availability status of the primary power source;

selectively enabling and disabling a generator to generate power based, at least in part, on the availability status; and

while employing the generator to generate power, employing a second number of rectifiers to rectify the generated power, wherein the first number is less than the second number.

19. The method of claim 18, further comprising:

routing at least power from the primary power source, generated power, or stored power to a communications interface.

20. The method of claim 18, further comprising:

employing a battery circuit to store generated power;

sensing a voltage of the battery circuit;

determining a rate of change of the voltage; and

determining a failure condition of the battery circuit based, at least in part, on the rate of change of the voltage.

21. The method of claim 18, further comprising:

employing a battery circuit to store generated power;

sensing a voltage of the battery circuit;

if the sensed voltage represents that the battery circuit has less than approximately a 20 percent charge, enabling the generator; and

if the sensed voltage of the battery circuit represents that the battery circuit has more than approximately an 82 percent charge, disabling the generator.

22. The method of claim 18, further comprising:

receiving an operational status of a back-haul that is coupled to a communications interface; and

selectively employing the generator based, at least in part, on the received operational status of the back-haul.

23. A tangible computer-readable medium for executing a method of providing generated power to a wireless communications system, the method comprising:

receiving power from a primary power source;

determining an availability status of the primary power source;

employing a battery circuit to store generated power;

determining a charge level of the battery circuit;

selectively enabling and disabling a generator to generate power based, at least in part, on the availability status and the charge level including;

enabling the generator if reduced availability is detected and the determining charge level is less than a lower threshold; and

disabling the generator if reduced availability is not detected or if the determining charge level is greater than an upper threshold.

24. The tangible computer-readable medium of claim 23, wherein the method further comprises:

while receiving power from the primary power source, employing a first number of rectifiers to rectify the power received from the primary power source;

while the generator is to generate power, employing a second number of rectifiers to rectify the generated power, wherein the first number is less than the second number.

25. The tangible computer-readable medium of claim 23, wherein the method further comprises:

sensing a voltage of the battery circuit;

determining a rate of change of the voltage; and

determining a failure condition of the battery circuit, based, at least in part, on the rate of change;

wherein the determining of the charge level of the battery circuit includes determining the charge level based, at least in part, on the sensed voltage;

wherein the lower threshold is approximately 20 percent; and

wherein the upper threshold is approximately 82 percent.

26. A system for generating power, comprising:

means for communicatively coupling a wireless interface to a back-haul;

means for providing power from a primary power source to the means for communicatively coupling;

means for selectively generating power;

means for storing power, wherein power from the means for selectively generating power is routable to the means for storing power and to the means for communicatively coupling, and wherein power from the means for storing power is routable to the means for communicatively coupling;

multiple means for rectifying power from the means for providing power from a primary power source and from the means for selectively generating power; and

means for controlling the generation, routing, and rectification of power, including means for individually enabling and disabling each of the multiple means for rectifying power based, at least in part, on an availability status of the primary power source.

27. The system of claim 26, further comprising:

means for sensing a voltage of the means for storing power; and

means for detecting a failure of the means for storing power based, at least in part, on a rate of change of the sensed voltage.

28. The system of claim 26, further comprising:

means for communicating operational data to a remote system.

29. A system for controlling power generation, comprising:

a communications systems base station, including;

a communications interface configured to communicatively couple a wireless interface to a back-haul;

a switch circuit that is configured to selectively switch power between multiple power sources and from the multiple power sources to the communications interface, wherein the multiple power sources, include;

a primary power interface configured to provide power from a primary power source to the communications interface;

a battery circuit interface configured to provide power to a battery circuit and to receive power from the battery circuit; and

a generator interface configured to provide power from a generator to the communications interface, to the battery circuit interface, or both; and

a power controller that is configured to enable a generator when reduced availability of the primary power source is detected and a sensed voltage of the battery circuit is below a first threshold and that is configured to disable the generator when reduced availability of the primary power source is not detected or when the sensed voltage of the battery circuit is above a second threshold.

30. The system of claim 29, wherein the switch circuit includes multiple rectifiers each configured to selectively rectify power from the primary power interface and/or from the generator, and wherein the power controller is further configured to individually enable and disable each of the multiple rectifiers based, at least in part, on an availability status of the primary power source to control the switching of the switch circuit and to enable and disable the generator based, at least in part, on an operational status of the back-haul.

31. The system of claim 29, wherein the power controller is further configured to enable the generator if a sensed voltage of the battery circuit represents that the battery circuit has less than approximately a 20 percent charge, and to disable the generator if the sensed voltage of the battery circuit represents that the battery circuit has more than approximately an 82 percent charge,

wherein the power controller further includes:

a watchdog circuit, and wherein the power controller is further configured to enable or disable the generator based, in part, on an output of the watchdog circuit, and

wherein the battery circuit includes;

a first battery having at least a first terminal and a second terminal;

a second battery having at least a first terminal and a second terminal;

a first jumper configured to connect the second terminal of the first battery to the first terminal of the second battery; and

an opto-isolator circuit configured to sense a voltage potential between the second terminal of the first battery and the second terminal of the second battery, and wherein the power controller is further configured to detect a battery circuit failure based, at least in part, on a rate of change of the sensed voltage.

32. A system for generating power, comprising:

a communications interface configured to communicatively couple a wireless interface to a telecommunications back-haul;

multiple power sources, including;

a primary power interface configured to provide power from a primary power source to the communications interface;

a back-up generator; and

a battery circuit, wherein the back-up generator is configured to be selectively enabled to generate power and to provide generated power to the communications interface, to the battery circuit, or both; and

wherein the battery circuit is configured to selectively provide power to the communications interface;

a power controller configured to intermittently operate the back-up generator based, at least in part, on a charge level of the battery circuit, wherein during reduced availability of the primary power source, operation of the communications interface system is enabled by consumption of at least 30 percent less fuel than required by another system having a back-up generator that is operated continuously during the reduced availability of the primary power source.