WO2018039227A1 - Electrical aggregation panel system - Google Patents

Abstract

Electrical aggregation panel system. The system may comprise an ATS with a first input connection that simultaneously provides a path between the ATS and a battery inverter, an electrical path between the ATS and a power grid, and an electrical path between the power grid and battery inverter, and a second input connection configured to provide a path between the ATS and battery inverter, and an output connection. The ATS may switch between providing a path between the first input connection and the output connection and a path between the second input connection and the output connection The system may further comprise an aggregation panel connected to the output connection of the ATS and connectable to at least one load, wherein the aggregation panel has a power rating equal to or greater than a sum of the power rating of the ATS and a power rating of the load.

Description

ELECTRICAL AGGREGATION PANEL SYSTEM

CROSS-REFERENCE TO RELATED APPLICATIONS

[1] This application claims priority to U.S. Provisional Patent App. No. 62/379, 157, filed on August 24, 2016, the entirety of which is hereby incorporated herein by reference.

BACKGROUND

[2] Field of the Invention

[3] The embodiments described herein are generally directed to an electrical aggregation panel system, and, more particularly, to a residential or commercial aggregation panel system comprising an automatic transfer switch (ATS) and aggregation panel.

[4] Description of the Related Art

[5] Residential alternative-energy generation and electrical storage systems have become commonplace. For instance, the installation of solar power generation systems is widespread. In addition, with advances in battery technology - both in terms of storage capacity and cost - implementation of electrical storage systems are becoming more feasible and economical. Combining solar power generation systems and battery systems provides a number of benefits that include: lower utility costs; power generation during peak usage; back-feeding electrical power to the utility during periods where residential usage is less than solar generation; peak-shifting utilizing the battery system; and critical load back-up power when the utility is "blacked out." However, in current installations, when the utility grid is offline, the ability to generate solar power is lost, and power to the critical load is limited to the amount of power provided by battery system.

[6] There are a number of alternative energy implementation possibilities:

[7] (1) Grid-Tied Solar: The utility grid source and solar power generation system are tied to the same utility panel. The amount of power that can be pulled from the grid is reduced by the amount of solar power generation capacity, in order to prevent overloading the panel. The residence pulls its power off this single panel for all of its uses.

[8] (2) Grid-Independent Solar, Battery, and Generator: An inverter system is installed to support the maximum residential energy use. Solar power generation and battery systems are tied to the inverter. The inverter and solar power generation system are tied to the same main utility panel, and the residence pulls its power off the main utility panel for all of its usage.

[9] (3) Grid-Tied Solar and Battery: The utility grid source is tied to the residence's main utility panel, and the residence pulls the non-critical power load from this main utility panel. An inverter system is installed to support the maximum residential critical energy use and is fed from the main utility panel. Power from the utility grid source is reduced by the capacity of the inverter system in order to prevent overloading the main utility panel. The battery system is tied to the inverter. The inverter and the solar power generation system are tied to the critical load panel, and the residence pulls its critical power from the critical load panel. The solar power generation system's capability cannot be larger than the inverter system.

[10] Current designs for grid-tied solar power generation and battery storage systems have several inherent disadvantages. Utility grid power to the critical load panel is limited to the electrical power rating of the battery inverter. Only solar power generation systems tied to the critical load panel will remain functional during a utility grid failure. The back-feeding of solar power from the solar power generation system to the utility grid is limited to the electrical power rating of the battery inverter. Only the circuits tied to the critical load panel will remain live during a failure of the utility grid.

[11] These disadvantages become apparent when the residence requires an excessive amount of energy, such as when the residential owner needs to charge an electrical vehicle. In this case, the residential owner must choose between two equally undesirable options: (1) install a battery inverter with a continuous power rating that is three to six times what the resident requires, in order to accommodate electrical vehicle charging; or (2) disallow electrical vehicle charging during a utility grid failure.

SUMMARY

[12] Accordingly, an aggregation panel system is disclosed.

[13] In an embodiment, an aggregation panel system is disclosed and comprises: an automatic transfer switch (ATS) that comprises a first input connection configured to simultaneously provide an electrical path between the ATS and a battery inverter, an electrical path between the ATS and a power grid, and an electrical path between the power grid and the battery inverter, a second input connection configured to provide an electrical path between the ATS and the battery inverter, and an output connection, wherein the ATS is configured to switch between providing a first electrical path between the first input connection and the output connection and providing a second electrical path between the second input connection and the output connection; and an aggregation panel electrically connected to the output connection of the ATS and electrically connectable to at least one load, wherein the aggregation panel has a power rating equal to or greater than a sum of the power rating of the ATS and a power rating of the load.

BRIEF DESCRIPTION OF THE DRAWINGS

[14] The details of the present invention, both as to its structure and operation, may be gleaned in part by study of the accompanying drawings, in which like reference numerals refer to like parts, and in which:

[15] FIG. 1 illustrates an ATS, according to an embodiment;

[16] FIG. 2 illustrates an aggregation panel, according to an embodiment;

[17] FIG. 3 illustrates a battery inverter, according to an embodiment; and

[18] FIG. 4 illustrates an aggregation panel system, according to an embodiment.

DETAILED DESCRIPTION

[19] Embodiments of an electrical aggregation panel system are disclosed. After reading this description, it will become apparent to one skilled in the art how to implement the invention in various alternative embodiments and alternative applications. Although the focus of this description is on residential aggregation panel systems, the various embodiments are not limited to residential applications and can also be used for and adapted for commercial use. However, although various embodiments of the present invention will be described herein, it is understood that these embodiments are presented by way of example and illustration only, and not limitation. As such, this detailed description of various embodiments should not be construed to limit the scope or breadth of the present invention as set forth in the appended claims.

[20] In current installation options, a residential owner must decide the solar power generation and battery system capacities at the time of installation. If no battery system is installed or the residential owner eventually requires more than the capacity of the installed battery system, the installation costs for adding capacity at a later time can be cost- prohibitive. In addition, due to existing technology designs, the amount of power that can be utilized from the utility grid is reduced by the capacity of the solar power generation system. For example, if the main utility panel is rated at 200 amps and the solar power generation system has a capacity of 80 amps, the utility grid capacity is reduced by the 80 amps of capacity provided by the solar power generation system, such that only 120 amps is available from the utility grid.

[21] In an embodiment, the disclosed electrical aggregation panel system provides one or more of the following advantages over existing technologies:

[22] (1) Ability to pull the full capacity from the utility grid when the utility grid is available;

[23] (2) Ability to install any capacity of solar power generation system(s), regardless of the size of the battery system;

[24] (3) Ability to fully utilize all available capacity of the solar power generation system(s), even when the utility grid is unavailable (e.g., due to a power failure); and/or

[25] (4) Ability to easily add or subtract battery system capacity as requirements change, without the need for complex and costly electrician services.

[26] In current practice, when a battery system is added, the power rating of the inverter is sized to match the wattage requirement of the load. In contrast, in an embodiment, the disclosed electrical aggregation panel system enables the inverter to match the wattage rating of the battery system, which may be an order of magnitude less than the wattage requirement of the load.

[27] In addition, in an embodiment, the disclosed electrical aggregation panel system ties together two Automatic Transfer Switches (ATSs). Specifically, standard battery inverter systems have ATS capabilities integrated into the unit acting as a first ATS, sized to match the power rating of the battery system. The disclosed electrical aggregation panel system ties this first ATS to a second ATS 110, which is sized to match the power rating of the utility grid source. This enables the user to incrementally add battery systems, using an ATS, up to the power rating of the utility grid source.

[28] In interconnected electrical systems, the electrical signals between disparate systems must be synchronized. In typical solar installations, the utility power feed provides the system "leadership," and the solar power generation system is in-phase or "follows" the utility power feed by synchronizing its signal to the utility signal. Battery systems have the ability to "lead" or "follow" the synchronization of electrical systems. This concept of "leader" and "follower" will be utilized throughout the present application.

[29] FIGS. 1 and 2 illustrate an electrical aggregation panel system, according to an embodiment. In the illustrated embodiment, the electrical aggregation panel system comprises an ATS 110 (e.g., ZTX series transfer switch from General Electric, ATC 300+ series transfer switch from Eaton, etc.), the amperage of the utility grid 120 (e.g., an input from the utility grid), and a battery inverter 130. The receptacle from battery inverter 130 is tied to both sides of ATS 110. ATS 110 connects an existing battery inverter 130, existing utility grid source 120, and an existing load 210. Inverter grid-in connection 150 is tied together with utility grid connection 160 to one side of ATS 110. Inverter AC out connection 170 is tied to the other side of ATS 110.

[30] ATS 110 is configured to switch between providing a first electrical path between a first input connection (i.e. 150/160) and the output connection to aggregation panel 180 and providing a second electrical path between a second input connection (i.e., 170) and the output connection to aggregation panel 180.

[31] Since ATS capabilities are integrated into standard battery inverters, conventional systems tie the utility grid to the grid outlet of a battery inverter. In these conventional systems, the battery inverter is then tied to an existing load. This requires either that the battery inverter be sized to the existing load or the installation of a smaller battery inverter to a smaller subset of the existing load. In such systems, the choice of the battery-inverter power rating must be made at the time of installation. Future changes are costly. In contrast, in embodiments of the disclosed electrical aggregation panel system, the battery-inverter capacity can be added incrementally at low cost at any time as existing load 210 changes (e.g., grows), and no critical load panel is required.

[32] Aggregation panel 180 has a power capacity that is the sum of the utility grid source 120 and the load 210, and aggregates battery 190, solar power generation system 220, utility grid 120, and load 210. Battery 190 (which may comprise one or a plurality of batteries) and utility grid 120 are bidirectional, whereas solar power generation system 220 only provides inbound power to aggregation panel 180, and load 210 only receives outbound power from aggregation panel 180. Solar power generation system 220 can be an inverter connected to a solar panel or a micro inverter connected to a solar panel.

[33] FIG. 3 illustrates battery inverter 130, according to an embodiment. In the illustrated embodiment, both inverter grid-in connection 150 (follower) and inverter AC out connection 170 (leader) are combined in a single five-conductor cable 310 that terminates in a five-pole plug 320 on one end and a standard existing battery inverter 130 on the other end. Five-conductor cable 310 may be of variable length, as specified by National Fire Protection Association (NFPA) 70® (the National Electrical Code®) or similar standard.

[34] FIG. 4 illustrates a full electrical aggregation panel system, according to an embodiment. The illustrated full electrical aggregation panel system incorporates design elements from FIGS. 1-3. Specifically, in an embodiment, ATS 110 and aggregation panel 180 are combined into a single enclosure. In addition, ATS 110 and aggregation panel 180 are each provided with one or more five-pole receptacles 410. Each five-pole receptacle 410 matches and is configured to receive or otherwise electrically connect to a five-pole plug 320 from an inverter 130.

[35] Advantageously, the full electrical aggregation panel system, disclosed herein, allows for the battery-inverter power rating to be smaller than that of the power rating of the maximum load 210. Incremental additions of battery-inverter power capacity can be added (e.g., by adding new battery inverter(s) 130 or replacing existing battery inverter(s) 130) as the power rating of load 210 increases. This is in contrast to conventional systems, in which the size of the battery inverter and the load to be powered by the battery inverter must be decided at the time of the initial installation.

[36] The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is to be understood that the description and drawings presented herein represent a presently preferred embodiment of the invention and are therefore representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments that may become obvious to those skilled in the art and that the scope of the present invention is accordingly not limited.

Claims

CLAIMS What is claimed is:

1. A system comprising:

an automatic transfer switch (ATS) that comprises

a first input connection configured to simultaneously provide an electrical path between the ATS and a battery inverter, an electrical path between the ATS and a power grid, and an electrical path between the power grid and the battery inverter, a second input connection configured to provide an electrical path between the ATS and the battery inverter, and

an output connection,

wherein the ATS is configured to switch between providing a first electrical path between the first input connection and the output connection and providing a second electrical path between the second input connection and the output connection; and

an aggregation panel electrically connected to the output connection of the ATS and electrically connectable to at least one load, wherein the aggregation panel has a power rating equal to or greater than a sum of the power rating of the ATS and a power rating of the load.

2. The system of Claim 1, wherein one or both of the first input connection and the second input connection of the ATS comprises a five-pole connector.

3. The system of Claim 1, wherein the aggregation panel is electrically connectable to at least one secondary source, and wherein the at least one secondary source comprises a power generator.

4. The system of Claim 3, wherein the power generator comprises at least one inverter connected to a solar panel.

5. The system of Claim 4, wherein the at least one inverter connected to the solar panel is a solar inverter.

6. The system of Claim 5, wherein the at least one inverter connected to the solar panel is a micro inverter.

7. The system of Claim 1, wherein the aggregation panel is electrically connectable to at least one secondary source, and wherein the at least one secondary source comprises a battery inverter.

8. The system of Claim 7, wherein the battery inverter comprises a five-pole connector.

9. The system of Claim 7, further comprising a conductor cable that comprises: a first end configured to connect to the battery inverter; and

a second end comprising a five-pole connector configured to connect to a five-pole connector of the ATS.

10. The system of Claim 9, wherein the first end of the conductor cable comprises: a first connection configured to connect to a grid input of the battery inverter; and a second connection configured to connect to an alternating current (AC) output of the battery inverter.

11. A method comprising using an automatic transfer switch (ATS) with a first input connection, a second input connection, and an output connection to an aggregation panel to:

switch between providing a first electrical path between the first input connection and the output connection and providing a second electrical path between the second input connection and the output connection,

wherein the first input connection simultaneously provides an electrical path between the ATS and a battery inverter, an electrical path between the ATS and a power grid, and an electrical path between the power grid and the battery inverter, and

wherein the second input connection provides an electrical path between the ATS and the battery inverter.