Power Modulation for Fuel Cell Powered Datacenters

• US 20170214070A1
• Filed: 05/01/2016
• Published: 07/27/2017
• Est. Priority Date: 01/25/2016
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: BIANCHINI, Ricardo, WANG, Di, GOVINDAN, Sriram, SIEGLER, John J., PETERSON, Eric, LIU, Jie, JAMES, Sean M., KELLY, Bryan
• Granted Patent: US 10,199,669 B2
• Time in Patent Office: Days
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 31/371 with remote indication, e.g. on external chargers
• CPC Class Codes: G01R 31/3835 involving only voltage measurements
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: H01M 2250/10 Fuel cells in stationary systems, e.g. emergency power source in plant
• CPC Class Codes: H01M 8/04544 Voltage
• CPC Class Codes: H01M 8/04597 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04604 Power, energy, capacity or load
• CPC Class Codes: H01M 8/04664 Failure or abnormal function
• CPC Class Codes: H01M 8/04753 of fuel cell reactants
• CPC Class Codes: H01M 8/04865 Voltage
• CPC Class Codes: H01M 8/04925 Power, energy, capacity or load
• CPC Class Codes: Y02B 90/10 Applications of fuel cells in buildings
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A fuel cell power controller tracks load current and fuel cell output voltage, and alerts on excessive fuel cell ramp rate, so another power source can supplement the fuel cell and/or the load can be reduced. A power engineering process makes efficient use of available fuel cell power by ramping up power flow rapidly when power is available, while respecting the ramp rate and other power limitations of the fuel cell and safety limitations of the load. Power flow decreases after an alert indicating an electrical output limitation of the fuel cell. Permitted power flow increases in response to a power demand increase (actual or requested) from the load in the absence of the alert. Power flow may increase or decrease in a fixed amount, a proportional amount, or per a sequence. A power controller relay may trip open on a low fuel cell output voltage or high load current.

Claims

1. A fuel cell power controller suitable for use in a data center, the fuel cell power controller comprising:

at least one of the following sensors;

a digital server load current sensor which upon connection in a power system provides load current sensor values that track a load current of at least one digital server, or a fuel cell output voltage sensor which upon connection in a power system provides output voltage sensor values that track an output voltage of a fuel cell;

a power controller processor with executable instructions that upon execution by the power controller processor monitor at least a portion of the sensor values; and

a ramp rate alert signal line which is triggered by the power controller processor when the executable instructions make a determination that a ramp rate of the fuel cell exceeds a previously specified ramp rate threshold, the determination based at least in part on at least one of the sensor values.

2. The fuel cell power controller of claim 1, further comprising at least one programming line connected to the power controller processor which signals the executable instructions to program at least one of the following:

a load current alert level, an output voltage alert level, or the ramp rate threshold.

3. The fuel cell power controller of claim 1, further comprising a relay which trips open at a specified relay activation level, thereby interrupting a current flow path.

4. The fuel cell power controller of claim 3, wherein the relay activation level is programmable through at least one programming line connected to the power controller processor.

5. The fuel cell power controller of claim 3, wherein the relay is activated by at least one of the following:

a load current sensor value above a previously specified load current relay trip level, or an output voltage sensor value below a previously specified output voltage relay trip level.

6. The fuel cell power controller of claim 1, in operable combination with an electromechanical fuel cell flow rate processor, wherein the executable instructions send a decrease power signal to the fuel cell flow rate processor to decrease fuel cell output voltage by modifying at least one flow rate of material into the fuel cell, the decrease power signal being sent in response to the determination that the ramp rate of the fuel cell exceeds the specified ramp rate threshold.

7. The fuel cell power controller of claim 1, in operable combination with an electromechanical fuel cell flow rate processor, wherein the executable instructions send an increase power signal to the fuel cell flow rate processor to increase fuel cell output voltage by modifying at least one flow rate of material into the fuel cell, the increase power signal being sent when the ramp rate of the fuel cell does not exceed the specified ramp rate threshold.

8. The fuel cell power controller of claim 1, in operable combination with the fuel cell.

9. The fuel cell power controller of claim 8, wherein the fuel cell comprises at least one of the following:

a proton exchange membrane fuel cell, a phosphoric acid fuel cell, a solid oxide fuel cell, a hydrogen-oxygen fuel cell, a molten carbonate fuel cell, or a polymer electrolyte membrane fuel cell.

10. The fuel cell power controller of claim 1, in operable combination with the one or more digital servers whose load current is tracked by the digital server load current sensor.

11. The fuel cell power controller and the one or more digital servers of claim 10, in operable combination with the fuel cell.

12. A fuel cell power engineering process, comprising:

a fuel cell power controller permitting electrical power to flow from a fuel cell to an electrical device at a level of power;

the fuel cell power controller decreasing the level of electrical power flow to the electrical device in response to an alert signal which indicates an electrical output limitation of the fuel cell; and

the fuel cell power controller increasing the level at which electrical power is permitted to flow to the electrical device in response to a power demand increase from the electrical device and the absence of the alert signal.

13. The process of claim 12, further comprising generating the alert signal in response to at least one of the following conditions:

a ramp rate of the fuel cell exceeds a previously specified ramp rate threshold;

an output voltage level of the fuel cell crosses a previously specified output voltage threshold;

or

a load current level of the electrical power flow to the electrical device crosses a previously specified load current threshold.

14. The process of claim 13, further comprising specifying the ramp rate threshold.

15. The process of claim 12, further comprising making the power demand increase as at least one of the following responses:

as a response after an increase in computational work performed by at least one digital server;

or

as a response to a request for increased power to permit a subsequent increase in computational work performed by at least one digital server.

16. The process of claim 12, comprising the power controller repeatedly increasing the level at which electrical power is permitted to flow until the alert signal occurs or until a predetermined maximum power level is reached.

17. The process of claim 16, comprising the power controller subsequently decreasing the level at which electrical power is permitted to flow, by at least one of the following:

a single fixed amount, an amount which is proportional to a previous increase of the level, or a sequence of different amounts.

18. The process of claim 16, wherein the power controller increases the level at which electrical power is permitted to flow at a rate which is less than a load following rate of the fuel cell.

19. A fuel cell power engineering process, comprising:

a fuel cell power controller permitting electrical power to flow from a fuel cell to a digital server at a level of power;

the fuel cell power controller decreasing the level of electrical power flow to the digital server in response to an alert signal which indicates an electrical output limitation of the fuel cell;

the fuel cell power controller increasing the level at which electrical power is permitted to flow to the digital server in response to a power demand increase from the digital server and the absence of the alert signal; and

programmatically setting at least one of the following levels for the fuel cell power controller;

a load current alert level,

a fuel cell voltage alert level,

a relay activation level of a relay of the power controller which is tripped open on a specified high current,

a relay activation level of a relay of the power controller which is tripped open on a specified low voltage, or

a relay activation level of a relay of the power controller which is tripped open on either or both of the following;

a specified high current, a specified low voltage.

20. The process of claim 19, further comprising at least two of the following:

generating the alert signal when a ramp rate of the fuel cell exceeds a previously specified ramp rate threshold;

generating the alert signal when an output voltage level of the fuel cell crosses a previously specified output voltage threshold;

generating the alert signal when a load current level of the electrical power flow to the electrical device crosses a previously specified load current threshold;

applying a default power cap which promotes safe operation;

tracking a load current of the digital server;

tracking an output voltage of the fuel cell;

opening a relay, thereby interrupting electrical power flow to the digital server;

or

sending a signal to a fuel cell flow rate processor of the fuel cell.