Transformer rectifier unit power quality protection

Patent metadata

Field	Value
Publication number	US-11349299-B2
Application number	US-202016820598-A
Country	US
Kind code	B2
Filing date	Mar 16, 2020
Priority date	Mar 16, 2020
Publication date	May 31, 2022
Grant date	May 31, 2022

Abstract

A system includes a transformer rectifier unit (TRU) having three inputs, a first AC bus configured to supply power to a first of the three inputs, a second AC bus configured to supply power to a second of the three inputs, and a third AC bus configured to supply power to a third of the three inputs. The system includes a power quality sense device electrically connected to each of the first, second and third AC busses. The system includes an electrically held contactor electrically connected between the TRU and the power quality sense device. The electrically held contactor is configured and adapted to be switched ON or OFF depending on whether the power quality sense device is energized or de-energized.

First claim

What is claimed is:

1. A system comprising:
a transformer rectifier unit (TRU) having three inputs;
a first AC bus configured to supply power to a first of the three inputs;
a second AC bus configured to supply power to a second of the three inputs;
a third AC bus configured to supply power to a third of the three inputs;
a power quality sense device electrically connected to each of the first, second and third AC busses;
an electrically held contactor electrically connected between the TRU and the power quality sense device, wherein the electrically held contactor is configured and adapted to be switched ON or OFF depending on whether the power quality sense device is energized or de-energized; and
a DC bus electrically connected to the electrically held contactor, wherein the electrically held contactor is between the output of the TRU and the DC bus.

2. The system as recited in claim 1 , wherein the power quality sense device is configured to be energized if the power quality across the AC busses is within a selected acceptable range.

3. The system as recited in claim 1 , wherein the electrically held contactor is switched ON when the power quality sense device is energized.

4. The system as recited in claim 1 , wherein the power quality sense device is configured to be de-energized if the power quality across the AC busses is outside of a selected acceptable range.

5. The system as recited in claim 1 , wherein the electrically held contactor is switched OFF when the power quality sense device is energized.

6. The system as recited in claim 1 , further comprising a 28V power supply electrically connected in series to the electrically held contactor.

7. The system as recited in claim 1 , wherein the power quality sense device is configured and adapted to sense frequency and current of at least one of the first, second or third AC busses.

8. The system as recited in claim 1 , further comprising respective overcurrent protectors on the first, second and third AC busses.

9. The system as recited in claim 1 , wherein the power quality sense device is electrically connected to each of the first, second and third AC busses at respective sense points between the respective overcurrent protectors and the three inputs of the TRU.

10. A method of power quality detection comprising:
detecting a power quality in at least one of three AC busses with a power quality sense device;
energizing the power quality sense device and switching an electrically held contactor ON if the power quality in at least one of the three AC busses is within a selected acceptable range; and
de-energizing the power quality sense device and switching an electrically held contactor OFF if the power quality in at least one of the three AC busses is outside of the selected acceptable range to stop power to a DC bus, wherein the electrically held contactor is between the at least one of three AC busses and the DC bus.

11. The method as recited in claim 10 , wherein detecting the power quality includes detecting at least one of voltage or frequency.

12. The method as recited in claim 10 , the selected acceptable range includes a selected acceptable voltage range and a selected acceptable frequency range.

13. The method as recited in claim 10 , further comprising a 28V power supply electrically connected in series to the electrically held contactor and the power quality sense device, wherein energizing the power quality sense device includes providing a ground path through the energizing sense device for the 28V power supply, thereby switching the electrically held contactor ON.

14. The method as recited in claim 10 , further comprising a 28V power supply electrically connected in series to the electrically held contactor and the power quality sense device, wherein de-energizing the power quality sense device includes breaking a ground path through the energizing sense device for the 28V power supply, thereby switching the electrically held contactor OFF.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Seagren Robert L

Classifications

• H02M7/068 Primary

  mounted on a transformer · CPC title

• H02J9/062

  for AC powered loads · CPC title

• H02H3/50

  responsive to the appearance of abnormal wave forms, e.g. AC in DC installations · CPC title

• H02H7/125 Primary

  for rectifiers · CPC title

• H02M1/32

  Means for protecting converters other than automatic disconnection · CPC title