System and method for maintaining proper phase neutral wiring in a power system

• US 9,667,097 B2
• Filed: 12/07/2012
• Issued: 05/30/2017
• Est. Priority Date: 12/26/2011
• Status: Active Grant

• Current Assignee: Schneider Electric IT Corporation (Schneider Electric SE)
• Original Assignee: Schneider Electric IT Corporation (Schneider Electric SE)
• Inventors: Ghosh, Rajesh, Tolakanahalli, Pradeep, Agrawal, Mahima
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Yeshaw, Esayas
• Application Number:
  US14/368,679
• Publication Number:
  US 20140333138A1
• Time in Patent Office: 1,635 Days
• Field of Search: 307 66
• CPC Class Codes: G01R 31/42 AC power supplies
• CPC Class Codes: G01R 31/52 Testing for short-circuits, leakage current or ground faults
• CPC Class Codes: G01R 31/55 Testing for incorrect line connections
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24
• CPC Class Codes: H02J 13/00016 using a wired telecommunication network or a data transmission bus
• CPC Class Codes: H02J 3/46 Controlling of the sharing of output between the generators, converters, or transformers
• CPC Class Codes: H02J 9/061 for DC powered loads
• CPC Class Codes: H02J 9/062 for AC powered loads
• CPC Class Codes: H02J 9/063 Common neutral, e.g. AC input neutral line connected to AC output neutral line and DC middle point
• 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: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 20/12 Energy storage units, uninterruptible power supply [UPS] systems or standby or emergency generators, e.g. in the last power distribution stages
• CPC Class Codes: Y04S 20/248 UPS systems or standby or emergency generators
• CPC Class Codes: Y04S 40/124 using wired telecommunication networks or data transmission busses

Abstract

According to one aspect, embodiments of the invention provide a method of operating a UPS system, the method comprising receiving, at an input of a first UPS, input power from a power source, generating, with a first analysis circuit, a first signal indicative of a characteristic of the input power, receiving, at the analysis circuit, a second signal from a second analysis circuit of a device coupled to the power source, the second signal indicative of a characteristic of input power received at the second analysis circuit, analyzing with the analysis circuitry, the first signal and the second signal, determining, whether an improper wiring condition exists at the input, in response to a determination that an improper wiring condition does not exist, providing output power to an output of the first UPS, and in response to a determination that an improper wiring condition does exist, de-energizing the first UPS.

Claims

1. A method of operating a UPS system having a first UPS, the method comprising:

receiving, at an input of the first UPS, input power from a power source;

generating, with a first analysis circuit within the first UPS, a first signal containing information indicative of a signal characteristic of the input power received by the first UPS;

receiving, at the first analysis circuit, a second signal from a second analysis circuit of a device coupled to the power source, the second signal containing information indicative of a signal characteristic of input power received by the device;

analyzing, with the first analysis circuit, the first signal from the first analysis circuit of the first UPS and the second signal from the second analysis circuit of the device;

determining, in response to analyzing the first signal and the second signal, whether an improper wiring condition exists at the input of the first UPS;

in response to a determination, based on the analysis of the first signal and the second signal, that an improper wiring condition does not exist at the input, providing output power to an output of the first UPS; and

in response to a determination, based on the analysis of the first signal and the second signal, that an improper wiring condition does exist at the input, de-energizing the first UPS.

2. The method of claim 1, wherein generating a first signal includes:

monitoring zero-crossing information of the input power received by the first UPS; and

generating the first signal containing zero-crossing information of the input power received by the first UPS.

3. The method of claim 2, wherein analyzing includes comparing the first signal containing zero-crossing information with the second signal, the second signal containing zero-crossing information of the input power received by the device.

4. The method of claim 1, wherein generating a first signal includes:

monitoring polarity information of the input power received by the first UPS; and

generating the first signal containing polarity information of the input power received by the first UPS.

5. The method of claim 4, wherein analyzing includes comparing the first signal containing polarity information with the second signal, the second signal containing polarity information of the input power received by the device.

6. The method of claim 1, wherein receiving the second signal includes receiving the second signal from the second analysis circuit via a communication bus coupled between the first UPS and the second analysis circuit.

7. The method of claim 6, further comprising transmitting the first signal to the second analysis circuit via the communication bus.

8. The method of claim 6, wherein receiving the second signal further includes receiving the second signal from the device, wherein the device is a second UPS coupled to the power source.

9. The method of claim 6, wherein receiving the second signal further includes receiving the second signal from the second analysis circuit, wherein the second analysis circuit is within a PSBP panel coupled to the power source.

10. The method of claim 1, wherein de-energizing the first UPS includes de-coupling the first UPS from the power source.

11. The method of claim 1, further comprising:

detecting, at an output of the first UPS, output power provided to a load;

generating, with the first analysis circuit, a third signal containing information indicative of a signal characteristic of the output power detected at the output of the first UPS;

receiving, at the first analysis circuit, a fourth signal from a second UPS, the fourth signal containing information indicative of a signal characteristic of output power detected at an output of the second UPS;

analyzing, with the first analysis circuit, the third signal and the fourth signal;

determining, in response to analyzing, whether an improper wiring condition exists at the output of the first UPS;

in response to a determination that an improper wiring condition does not exist at the output, providing output power to the output of the first UPS; and

in response to a determination that an improper wiring condition does exist at the output, de-energizing the first UPS.

12. A UPS comprising:

an input to receive input power from a power source;

an output to provide output power to a load;

a first analysis circuit coupled to the input and configured to be coupled to a communication bus; and

control circuitry coupled to the first analysis circuit;

wherein the first analysis circuit is configured to generate a first signal containing information indicative of a signal characteristic of the input power at the input, receive via the communication bus a second signal from a second analysis circuit of a device coupled to the power source, the second signal containing information indicative of a signal characteristic of input power received by the device, analyze the first signal from the first analysis circuit of the UPS and the second signal from the second analysis circuit of the device, and determine, based on the first and second signal analysis, whether an improper wiring condition exists at the input,

wherein, in response to a determination, based on the analysis of the first signal and the second signal, that an improper wiring condition does not exist at the input, the control circuitry is configured to operate the UPS to provide output power to the output, and

wherein, in response to a determination, based on the analysis of the first signal and the second signal, that an improper wiring condition does exist at the input, the control circuitry is configured to de-energize the UPS.

13. The UPS of claim 12, further comprising a relay coupled to the input and the control circuitry, wherein in response to a determination by the first analysis circuit that the first and second signals are in phase, the control circuitry is configured to close the relay, allowing that the UPS to provide output power to the output, and wherein, in response to a determination by the first analysis circuit that the first and second signals are out of phase, the control circuitry is configured to open the relay to de-energize the UPS.

14. The UPS of claim 12, wherein the first analysis circuit is further coupled to the output and is further configured to generate a third signal containing information indicative of a signal characteristic of the output power at the output, receive via the communication bus a fourth signal from the second analysis circuit, the fourth signal containing information indicative of a signal characteristic of output power at a second UPS containing the second analysis circuit, analyze the third signal and the fourth signal, and determine, based on the third and fourth signal analysis, whether an improper wiring condition exists at the output,

wherein, in response to a determination that an improper wiring condition does not exist at the output, the control circuitry is configured to close the relay so that the UPS provides output power to the output, and

wherein, in response to a determination that an improper wiring condition does exist at the output, the control circuitry is configured to open the relay to de-energize the UPS.

15. The UPS of claim 12, wherein the first analysis circuit comprises:

a first zero-crossing detector coupled to the input; and

a wrong wiring detector coupled to the zero-crossing detector, the control circuitry and the communication bus,

wherein the first zero-crossing detector is configured to monitor zero-crossing information of input power received at the input and generate the first signal, the first signal containing zero-crossing information of the input power received at the input, and

wherein the wrong wiring detector is configured to compare the first signal containing zero-crossing information with the second signal, the second signal containing zero-crossing information of the input power received by the device.

16. The UPS of claim 15, wherein the wrong wiring detector is further configured to receive the second signal containing zero-crossing information from a second zero-crossing detector within a second UPS coupled to the power source.

17. The UPS of claim 15, wherein the wrong wiring detector is further configured to receive the second signal containing zero-crossing information from a second zero-crossing detector within a PSBP coupled to the power source.

18. The UPS of claim 12, wherein the first analysis circuit comprises:

a first DSP coupled to the input,

wherein the DSP is configured to monitor polarity information of input power received at the input, generate the first signal containing polarity information of the input power received at the input, and compare the first signal containing polarity information with the second signal, the second signal containing polarity information of the input power received by the device.

19. The UPS of claim 17, wherein the first DSP is further configured to receive the second signal containing polarity information from a second DSP within a second UPS coupled to the power source.

20. A parallel UPS system, the system comprising:

a plurality of UPS'"'"'s coupled in parallel, each UPS including;

at least one phase input coupled to a power source via a mains bus;

a neutral input coupled to the power source via the mains bus;

at least one phase output coupled to a load via a load bus;

a neutral output coupled to the load via the load bus; and

means for identifying incorrect wiring of the at least one phase input and the neutral input to the mains bus and the at least one phase output and the neutral output to the load bus.