Systems and methods for power interruption

• US 9,438,027 B2
• Filed: 03/15/2013
• Issued: 09/06/2016
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Acleap Power Incorporated
• Original Assignee: General Electric Company
• Inventors: Turner, Gary Jay, Smith, Darwin Drake, Walter, Tab O.
• Primary Examiner(s): Tran, Thienvu
• Assistant Examiner(s): Comber, Kevin J
• Application Number:
  US13/836,841
• Publication Number:
  US 20140268454A1
• Time in Patent Office: 1,271 Days
• Field of Search: 361/79
• US Class Current: 1/1
• CPC Class Codes: H02H 3/20 responsive to excess voltage
• CPC Class Codes: H02H 3/42 responsive to product of voltage and current

Abstract

A power interruption circuit for use in a power distribution module is provided. The power interruption circuit is configured to provide power to a load and includes a shunt resistor, a plurality of switches, and microprocessor. The microprocessor is configured to determine a digitized value of a current flowing through the shunt resistor, determine a digitized value of an output voltage of the power interruption circuit, calculate, from the digitized current value and the digitized output voltage value, a power provided by the power interruption circuit to the load, compare the calculated power to a threshold power level, and control the plurality of switches based on the comparison.

Claims

1. A power interruption circuit for use in a power distribution module, said power interruption circuit configured to provide direct current (DC) power to a load and comprising:

a shunt resistor;

a plurality of switches;

a microprocessor configured to;

calculate a resistance of said shunt resistor based on a measured temperature of said shunt resistor;

determine a digitized value of a current flowing through said shunt resistor;

determine a digitized value of a DC output voltage of said power interruption circuit;

calculate, from the digitized current value and the digitized output voltage value, a power provided by said power interruption circuit to the load;

adjust the calculated power to correct errors determined based on a measured ambient temperature;

compare the calculated power to a threshold power level; and

control said plurality of switches based on the comparison;

an amplifier configured to amplify a DC voltage across said shunt resistor; and

an analog to digital converter configured to convert the amplified voltage into a digitized shunt voltage value, wherein said microprocessor is further configured to;

determine the digitized value of the current based on the digitized shunt voltage value and the calculated resistance.

2. A power interruption circuit in accordance with claim 1, wherein said shunt resistor is coupled in series with at least one of said plurality of switches.

3. A power interruption circuit in accordance with claim 1, wherein said plurality of switches comprises two switches.

4. A power interruption circuit in accordance with claim 1, wherein to control said plurality of switches based on the comparison, said microprocessor is configured to:

maintain said plurality of switches in a closed position when the calculated power is less than or equal to the threshold power level; and

switch said plurality of switches from the closed position to an open position when the calculated power is greater than the threshold power level.

5. A power interruption circuit in accordance with claim 1, wherein the threshold power level is 100 Volt-amperes (VA).

6. A power distribution module for use in a power distribution system, said power distribution module comprising:

a plurality of power interruption circuits, wherein each of said plurality of power interruption circuits is configured to provide direct current (DC) power to a respective load, each of said plurality of power interruption circuits comprising;

a shunt resistor;

a plurality of switches;

an amplifier configured to amplify a DC voltage across said shunt resistor;

an analog to digital converter configured to convert the amplified voltage into a digitized shunt voltage value; and

a microprocessor configured to;

calculate a resistance of said shunt resistor based on a measured temperature of said shunt resistor;

determine a digitized value of a current flowing through said shunt resistor based on the digitized shunt voltage value and the calculated resistance;

determine a digitized value of a DC output voltage of said power interruption circuit;

calculate, from the digitized current value and the digitized output voltage value, a power provided by said power interruption circuit to the respective load;

adjust the calculated power to correct errors determined based on an age of said power distribution module;

compare the calculated power to a threshold power level; and

control said plurality of switches based on the comparison.

7. A power distribution module in accordance with claim 6, wherein said shunt resistor is coupled in series with at least one of said plurality of switches.

8. A power distribution module in accordance with claim 6, wherein said plurality of switches comprises two switches.

9. A power distribution module in accordance with claim 6, wherein to control said plurality of switches based on the comparison, said microprocessor is configured to:

maintain said plurality of switches in a closed position when the calculated power is less than or equal to the threshold power level; and

switch said plurality of switches from the closed position to an open position when the calculated power is greater than the threshold power level.

10. A power distribution module in accordance with claim 6, wherein said plurality of power interruption circuits comprises eight power interruption circuits.

11. A method for controlling direct current (DC) power supplied to a load through a current interruption circuit, said method comprising:

determining, using a processing device, a digitized value of a current flowing through a shunt resistor in the current interruption circuit, the determining comprising;

amplifying a DC shunt voltage across the shunt resistor; and

converting the DC shunt voltage into a digitized value of the DC shunt voltage;

calculating a resistance of the shunt resistor based on a measured temperature of the shunt resistor; and

determining the digitized value of the current based on the digitized DC shunt voltage value and the calculated resistance;

calculating, using the processing device, a DC power provided by the current interruption circuit to the load, the power calculated from the digitized current value and the digitized output voltage value;

adjusting the calculated DC power to correct errors determined based on an age of the power distribution module;

comparing the calculated DC power to a threshold power level; and

controlling at least one switch in the current interruption circuit based on the comparison.

12. A method in accordance with claim 11, wherein controlling at least one switch in the current interruption circuit based on the comparison comprises:

maintaining the at least one switch in a closed position when the calculated power is less than or equal to the threshold power level; and

switching the at least one switch from the closed position to an open position when the calculated power is greater than the threshold power level.

13. A method in accordance with claim 11, wherein comparing the calculated power to a threshold power level comprises comparing the calculated power to a threshold power level of 100 Volt-amperes (VA).

14. A method in accordance with claim 11, further comprising storing the calculated power on a memory device communicatively coupled to the processing device.