Method and system for measuring, monitoring and controlling electrical power consumption

• US 9,013,060 B2
• Filed: 06/14/2010
• Issued: 04/21/2015
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: Infosys Limited
• Original Assignee: Infosys Limited
• Inventors: Katru, Siva Prasad, Padmanabh, Kumar, Paul, Sanjoy
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): PEREZ BORROTO, ALFONSO
• Application Number:
  US12/814,747
• Publication Number:
  US 20110266869A1
• Time in Patent Office: 1,772 Days
• Field of Search: 307/11, 307 38- 39, 307/131
• US Class Current: 307/39
• CPC Class Codes: H02J 13/00004 characterised by the power network being locally controlled
• CPC Class Codes: H02J 13/00017 using optical fiber
• CPC Class Codes: H02J 13/00026 involving a local wireless network, e.g. Wi-Fi, ZigBee or Bluetooth
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: H02J 2310/14 The load or loads being home appliances
• CPC Class Codes: H02J 3/14 by switching loads on to, or off from, network, e.g. progressively balanced loading
• 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 70/3225 Demand response systems, e.g. load shedding, peak shaving
• 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: Y04S 20/222 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 20/242 Home appliances
• CPC Class Codes: Y04S 40/124 using wired telecommunication networks or data transmission busses
• CPC Class Codes: Y04S 40/126 using wireless data transmission

Abstract

A system and method for measuring, monitoring and controlling electrical power directed through one or more electricity directing devices is provided. The one or more electricity directing devices includes electrical sockets supplying power to one or more devices. The system includes a potential transformer configured to receive AC voltage directed through a socket and further configured to relay the voltage to a processing device. The system further includes a current sensor configured to sense current drawn from the socket and further configured to relay the current to the processing device. A microcontroller is adapted to receive analog or digital values of voltage and current corresponding to AC voltage and AC current. The microcontroller then measures values of voltage and current, calculate electrical power consumed and generate a control signal. The control signal activates a switching device operationally connected to the socket and switches power flow through the socket.

Claims

1. A system for measuring, monitoring and controlling electrical power directed through one or more electricity directing devices, wherein the one or more electricity directing devices comprises one or more electrical sockets supplying power to one or more devices, the system comprising one or more circuits, each circuit comprising:

a potential transformer configured to receive single phase AC voltage directed through a socket and further configured to relay the voltage, wherein relaying the AC voltage comprises stepping down the voltage using a precise value of transformation ratio;

a current sensor configured to sense current drawn from the socket and further configured to relay the current;

a microcontroller configured to receive analog or digital values of voltage and current corresponding to the single phase AC voltage delivered by the potential transformer and current sensed by the current sensor, wherein the microcontroller is further configured to;

measure values of the single phase AC voltage and current provided at the socket;

determine over one cycle of the single phase AC voltage, a cumulative sum of modulus of instantaneous power values at the socket;

determine phase lag between the single phase AC voltage and current provided at the socket; and

for AC voltage and current separated by a phase lag, generate a control signal terminating power flow, wherein the control signal is generated responsive to a product of (i) the cumulative sum of modulus of instantaneous power values determined over one cycle of the single phase AC voltage and (ii) a cosine value of the phase lag between the AC voltage and current exceeding a predetermined value;

a coupling device configured to transmit the generated control signal to a switching device; and

a switching device operationally connected to the socket and configured to terminate power flow through the socket based on the received control signal.

2. The system of claim 1, wherein digital values of voltage and current received by the microcontroller are generated by an analog to digital controller located in a signal conditioning circuit, wherein the signal conditioning circuit is operationally connected to the potential transformer and the current sensor, and is configured to condition the analog AC voltage and current in order to make it suitable for measurement and further processing by the microcontroller.

3. The system of claim 1, wherein analog values of voltage and current received by the microcontroller are delivered by a signal conditioning circuit, wherein the signal conditioning circuit is operationally connected to the potential transformer and the current sensor, further wherein the microcontroller comprises an analog to digital converter configured to convert analog values of voltage and current into digital values.

4. The system of claim 1, wherein one or more conditioning operations are performed by a signal conditioning circuit on analog AC voltage and current sensed by the potential transformer and the current sensor, further wherein the one or more conditioning operations comprises amplification, attenuation, isolation, filtering, excitation and linearization.

5. The system of claim 1, wherein calculating electrical power by the microcontroller further comprises calculating reactive power.

6. The system of claim 1 further comprising an AC/DC power supply unit configured to supply power to components of the microcontroller.

7. The system of claim 1, wherein the coupling device is an Optocoupler.

8. The system of claim 1 wherein the switching device is a TRIAC.

9. The system of claim 1, wherein the switching device is a power relay.

10. The system of claim 1, wherein the one or more circuits are embedded in a power strip comprising the one or more electrical sockets, further wherein each circuit is configured to measure, monitor and control electrical power flow through corresponding electrical socket.

11. The system of claim 10, wherein the power strip comprises a rules engine, further wherein the rules engine comprises software code containing rules identifying one or more devices to be switched off based on control signals generated by the one or more circuits.

12. The system of claim 11, wherein the rules for switching the one or more devices comprises instructions for switching different devices at different time periods during a day.

13. The system of claim 11, wherein the rules engine allocates a power budget to the power strip and switches the one or more devices in case of the electrical power exceeding the power budget threshold.

14. The system of claim 10, wherein the power strip is configured to transmit calculated values of power to a server comprising a rules engine, further wherein the server is configured to control switching of the one or more devices based on rules stored in the rules engine.

15. The system of claim 10, wherein the power strip comprises additional circuitry for switching the one or more devices through a web based interface.

16. The system of claim 1, wherein the one or more circuits are embedded in a plurality of power strips comprising the one or more electrical sockets, further wherein the plurality of power strips are configured to communicate with each other for maintaining a software policy for power consumption.

17. The system of claim 1 further comprising a centralized server operationally connected to the microcontroller and configured to receive digital values of voltage and current from the microcontroller in order to calculate a power factor value and values of real, active and reactive power.

18. The system of claim 1, wherein the microcontroller is configured to wirelessly transmit calculated power values through a wireless device, further wherein the wireless device is adapted to remotely control switching of the one or more devices through text messaging.

19. The system of claim 18 further comprising an authentication mechanism for allowing remote control of switching of the one or more devices through specific mobile device numbers.

20. The system of claim 1, wherein the microcontroller is operationally connected to a computing device configured to control switching of the one or more devices through wireline connections.

21. The system of claim 1, wherein the one or more electricity directing devices are installed in an infrastructure facility.

22. The system of claim 21, wherein the infrastructure facility is an organization comprising one or more physical regions, further wherein a priority value is assigned to each of the one or more physical regions, and wherein the switching device is configured to control power flow to electricity consuming devices within each physical region based on the priority value assigned to said physical region.

23. The system of claim 22, wherein priority values are further assigned to the one or more electricity consuming devices within a physical region for switching the one or more electricity consuming devices based on the priority values.

24. The system of claim 1, wherein the microcontroller is further configured to perform fault diagnosis on the one or more electricity receiving devices, further wherein the fault diagnosis is performed by analyzing presence of higher harmonic frequencies in the AC voltage received by the potential transformer.

25. A method for measuring, monitoring and controlling electrical power directed through one or more electricity directing devices, wherein the one or more electricity directing devices comprises one or more electrical sockets supplying power to one or more electricity consuming devices, the method comprising:

receiving single phase AC voltage through an electricity directing device;

receiving AC current through the electricity directing device;

converting values of the single phase AC voltage and current into digital values;

based on the values of the single phase AC voltage and AC current received through the electricity directing device, determining over one cycle of the single phase AC voltage, a cumulative sum of modulus of instantaneous power values at said electricity directing device;

determining phase lag between the single phase AC voltage and current provided at the electricity directing device; and

for AC voltage and current separated by a phase lag, generating a control signal terminating power flow, wherein the control signal is generated responsive to a product of (i) the cumulative sum of modulus of instantaneous power values determined over one cycle of the single phase AC voltage and (ii) a cosine value of the phase lag between the AC voltage and current provided at the socket exceeding a predetermined value.

26. The method of claim 25, wherein the generated control signals are transmitted wirelessly to enable remote control of switching of the one or more devices.

27. The method of claim 25, wherein the generated control signals are provided to a computing device for physically controlling switching of the one or more devices.