Distributed power grid control with local VAR control

• US 10,063,055 B2
• Filed: 07/04/2015
• Issued: 08/28/2018
• Est. Priority Date: 07/04/2014
• Status: Active Grant

• Current Assignee: Apparent Labs LLC
• Original Assignee: Xslent Energy Technologies, LLC
• Inventors: Matan, Stefan, Horton, Fred C, Marrone, Frank P
• Primary Examiner(s): Chang, Joseph
• Application Number:
  US14/791,431
• Publication Number:
  US 20160087522A1
• Time in Patent Office: 1,151 Days
• Field of Search: 307 31
• CPC Class Codes: G01R 11/54 for measuring simultaneously at least two of the following three variables: real component, reactive component, apparent energy
• CPC Class Codes: G05B 13/026 using a predictor
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G05F 1/66 Regulating electric power
• CPC Class Codes: G06G 7/635 for determining the most economical distribution in power systems
• CPC Class Codes: H02J 13/00 Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
• CPC Class Codes: H02J 13/00002 characterised by monitoring
• CPC Class Codes: H02J 13/00004 characterised by the power network being locally controlled
• CPC Class Codes: H02J 13/00034 the elements or equipment being or involving an electric power substation
• CPC Class Codes: H02J 2300/20 The dispersed energy generation being of renewable origin
• CPC Class Codes: H02J 2310/10 The network having a local or delimited stationary reach
• CPC Class Codes: H02J 2310/16 The load or loads being an Information and Communication Technology [ICT] facility
• CPC Class Codes: H02J 3/00 Circuit arrangements for ac mains or ac distribution networks
• CPC Class Codes: H02J 3/01 Arrangements for reducing harmonics or ripples
• CPC Class Codes: H02J 3/06 Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
• CPC Class Codes: H02J 3/12 for adjusting voltage in ac networks by changing a characteristic of the network load
• CPC Class Codes: H02J 3/18 Arrangements for adjusting, eliminating or compensating reactive power in networks for adjustment of voltage H02J3/16
• CPC Class Codes: H02J 3/28 Arrangements for balancing of the load in a network by storage of energy
• CPC Class Codes: H02J 3/38 Arrangements for parallely feeding a single network by two or more generators, converters or transformers
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02M 1/42 : Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
• 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: Y02E 10/56 : Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 40/30 : Reactive power compensation
• CPC Class Codes: Y02E 40/40 : Arrangements for reducing harmonics
• CPC Class Codes: Y02E 40/70 : Smart grids as climate change mitigation technology in the energy generation sector
• CPC Class Codes: Y04S 10/123 : the energy generation units being or involving renewable energy sources
• 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 20/221 : General power management systems
• CPC Class Codes: Y04S 20/222 : Demand response systems, e.g. load shedding, peak shaving

Abstract

A distributed control node enables local control of reactive power. A metering device of the control node measures energy delivered by a grid network at a point of common coupling (PCC) to which a load is coupled. The metering device determines that the load draws reactive power from the grid network. The control node draws real power from the grid and converts the real power from the grid into reactive power. The conversion of real to reactive power occurs on the consumer side of the PCC. The conversion of real to reactive power enables delivery of reactive power to a local load from real power drawn from the grid.

Claims

1. A method for grid control, comprising:

measuring, with a metering device, energy delivered by a grid network at a point of common coupling (PCC) to which a load is coupled, where the metering device is located on a same side of the PCC as the load;

determining that the load draws reactive power from the grid network;

drawing real power from the grid network with an energy conversion device on the same side of the PCC as the load and the metering device in response to determining that the load draws reactive power from the grid network; and

converting, with the energy conversion device, the real power from the grid network into reactive power on the same side of the PCC to provide the reactive power to the load from real power from the grid network.

2. The method of claim 1, wherein the grid network comprises a utility power grid.

3. The method of claim 1, wherein the load is one of multiple loads coupled to the PCC.

4. The method of claim 1, wherein determining that the load draws reactive power further comprises:

identifying an energy signature unique to the load, the energy signature including a complex current vector for the load in operation identifying for the primary current a real power component and a reactive power component, and identifying for harmonics of the primary current a real power component, a reactive power component, and an angular displacement relative to the primary current.

5. The method of claim 1, wherein determining that the load draws reactive power further comprises:

determining whether the load requires leading or lagging reactive power; and

wherein converting the real power to reactive power comprises generating either leading or lagging power based on the determining.

6. The method of claim 1, wherein drawing real power from the grid network comprises:

drawing only real power from the grid network, and supplying all reactive power needs of the load from converting the real power into reactive power.

7. The method of claim 1, wherein measuring energy delivered at the PCC and determining that the load draws reactive power from the grid network comprises:

measuring and determining in response to control information received at the metering device from a data center of the grid network.

8. The method of claim 7, wherein measuring and determining in response to the control information received from the data center comprises receiving information from a controller of central management of a utility power grid.

9. A distributed control node within a power grid system, comprising:

a grid connector to couple a load to a grid network;

a metering device located on a same side of a point of common coupling (PCC) to the grid network as the load, the metering device to measure energy delivered by the grid network at the PCC, and determine if the load draws reactive power from the grid network; and

an energy conversion device separate from the load on the same side of the PCC as the load and the metering device to draw real power from the grid network in response to a a determination that the load draws reactive power from the grid network, and convert the real power from the grid network into reactive power on the same side of the PCC to provide the reactive power to the load from real power from the grid network.

10. The control node of claim 9, wherein the grid network comprises a utility power grid.

11. The control node of claim 9, wherein the load is one of multiple loads coupled to the PCC.

12. The control node of claim 9, wherein the metering device is further to identify an energy signature unique to the load, the energy signature including a complex current vector for the load in operation identifying for the primary current a real power component and a reactive power component, and identifying for harmonics of the primary current a real power component, a reactive power component, and an angular displacement relative to the primary current.

13. The control node of claim 9, wherein the metering device is further to determine whether the load requires leading or lagging reactive power;

and wherein the energy conversion device is to generate either leading or lagging power based on what the load requires.

14. The control node of claim 9, wherein the energy conversion device is to draw only real power from the grid network, and supply all reactive power needs of the load from converting the real power into reactive power.

15. The control node of claim 9, wherein the metering device is further to receive control information from a data center of the grid network.

16. The control node of claim 15, wherein the metering device is to receive control information from a controller of central management of a utility power grid.

17. A power grid system, comprising:

multiple loads electrically coupled to a same side of a point of common coupling (PCC); and

a control node coupled to the multiple loads at the PCC, the control node including

a metering device to measure energy delivered by a grid network at the PCC, and determine that at least one of the loads draws reactive power from the grid network; and

an energy conversion device to draw real power from the grid network in response to an indication from the metering device, and convert the real power from the grid network into reactive power on the same side of the PCC to deliver to the at least one load.

18. The power grid system of claim 17, wherein the metering device is further to determine whether the load requires leading or lagging reactive power;

and wherein the energy conversion device is to generate either leading or lagging power based on what the load requires.

19. The power grid system of claim 17, wherein the energy conversion device is to draw only real power from the grid network, and supply all reactive power needs of the load from converting the real power into reactive power.

20. The power grid system of claim 17, wherein the metering device is further to receive control information from a data center of the grid network.