WO2025006951A1

WO2025006951A1 - Distributed inverter systems for building integrated photovoltaic power generation

Info

Publication number: WO2025006951A1
Application number: PCT/US2024/036111
Authority: WO
Inventors: Hunter Mcdaniel; Matthew R. Bergren; Brian BILLSTRAND
Original assignee: Ubiqd Inc
Current assignee: Ubiqd Inc
Priority date: 2023-06-30
Filing date: 2024-06-28
Publication date: 2025-01-02
Anticipated expiration: 2025-12-30

Abstract

Various embodiments provide an electrical system. In an example embodiment, the electrical system includes a DC power source, a rapid DC power shutdown protection circuit, AC or DC grid sensing, and DC-to-AC or DC-to-DC power conversion.

Description

DISTRIBUTED INVERTER SYSTEMS FOR BUILDING INTEGRATED PHOTOVOLTAIC POWER GENERATION CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Application No.63/511,238, filed June 30, 2023, the content of which is incorporated by reference herein in its entirety. FIELD OF THE DISCLOSURE The present invention is directed to DC-to-AC power conversion from distributed power generation systems such as solar windows or other building-integrated photovoltaics, and more specifically to low-power DC systems that tap into a buildings existing AC grid in a safe and cost- effective way that enables wider deployment of electrical power systems. BACKGROUND OF THE DISCLOSURE Urban areas exhibit the highest energy demand and the fewest opportunities for utilizing renewable energy generation with traditional technologies. Building Integrated Photovoltaics (BIPV) are a potential solution that integrates solar generation into the building envelope. Implementation of BIPV technologies on urban buildings has been challenging due to high initial capital investments, long return on investment periods, high installation costs, and additional balance of systems (BOS) infrastructure required to connect BIPV with the grid. Consequently, soft costs and BOS associated with PV installation on residential and commercial buildings account for more than 70% of the installed cost per watt and the cost per watt is 85% more than utility scale solar. Therefore, a solution is needed to reduce the cost of urban solar to allow for economically competitive, sustainable power generation in order to improve energy efficiency of buildings, reduce emissions, and improve the resilience of energy infrastructure. The present solution is incorporating distributed low power density and low-cost power generation systems that utilize the building’s existing electrical infrastructure. Leveraging these mechanisms for installation has the potential to

1 LEGAL02/44543140v1 reduce initial capital investment, achieve return on investment of less than 5 years and reduce the need for grid scale energy storage and other BOS infrastructure. An objective of the present invention is a distributed inverter system that allows the power produced from a BIPV array to integrate directly into existing building electrical systems. All present solar electrical systems require dedicated circuits to avoid potential overload and are designed to support high power densities on the outside of the building. In one aspect, the present invention consists of a fully integrated max power point tracking solar microinverter that will monitor load on a shared circuit, as well as generated power, and safely use the excess load on those circuits to distribute the generated power to the grid on the shared circuit through the microinverter. Other aspects of the present invention include accurate shared circuit current sensing control logic and switching, limiting allowed power generation, optimization for low power density arrays, IOT connectivity, and installation within a form factor junction box inside the building. In this way the present invention can significantly reduce the electrical system cost, it will provide data on circuit specific energy usage, and generates power for continuous loads at their source reducing the need for additional grid level infrastructure. SUMMARY OF THE DISCLOSURE In one aspect, a system is provided including the present system that consists of a specialized max power point tracking (MPPT) controller designed for one or multiple solar window/BIPV panel inputs with wide voltage and current ratings to provide additional flexibility for a wide variety of different building designs, an AC inverter, and a single-phase current monitoring sensor in series with the shared circuit. Specifically, this MPPT controller system includes a capable microcontroller, current and voltage sensors, as well as a shunt resistor to accurately record the array IV characteristics, a Wi-Fi communications module for IOT connectivity, and a high frequency isolated DC-DC converter with interleaved current. BRIEF DESCRIPTION OF THE DRAWINGS

2 LEGAL02/44543140v1 Fig.1 shows a diagram of a traditional approach to integrating photovoltaics and the approach to integrating photovoltaics of the present invention. Fig.2 shows a diagram of the inverter system. Fig.3 shows a schematic diagram of the inverter system. Fig.4 shows another schematic diagram of the inverter system. Fig.5 shows a block diagram of a safe operation control logic flow. Fig.6 shows another diagram of safe operation control logic flow. DEFINITIONS AND ABBREVIATIONS The following explanations of terms and abbreviations are provided to better describe the present disclosure and to guide those of ordinary skill in the art in the practice of systems, methodologies and compositions disclosed herein. As used herein, “comprising” means “including”, and the singular form “a” or “an” or “the” include plural references unless the context clearly indicates otherwise. Unless the context clearly indicates otherwise, the term “or” is inclusive, and thus refers to both a single element of stated alternative elements and a combination of two or more of those elements. Unless explained otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one or ordinary skill in the art to which this disclosure relates. Suitable methods and compositions are described herein for the practice or testing of the systems, methodologies and compositions described herein. However, it is to be understood that other methods and materials similar, or equivalent to, those described herein may be used in the practice or testing of these systems, methodologies and compositions disclosed herein. Consequently, the systems, methodologies, compositions, and examples disclosed herein are illustrative only, and are not intended to be limiting. Other features of the present disclosure will be apparent to those skilled in the art from the following detailed description and the appended claims. Unless otherwise indicated, all numbers expressing quantities of components, percentages, temperatures, times, and so forth as used in the specification or claims are to be understood as

3 LEGAL02/44543140v1 being modified by the term “about”. Unless otherwise indicated, non-numerical properties such as colloidal, continuous, crystalline, and so forth as used in the specification or claims are to be understood as being modified by the term “substantially”, meaning to a great extent or degree. Accordingly, unless otherwise indicated implicitly or explicitly, the numerical parameter and/or non-numerical properties set forth herein are approximations, and the optimal values of these properties and parameters may depend on the desired properties sought, the limits of detection under standard test conditions or methods, the limitations of the processing methods, and/or the nature of the property or parameter. When directly and explicitly distinguishing embodiments from disclosed prior art, the embodiment numbers are not approximations unless the word “about” is recited. Photoluminescence (PL): The emission of light (electromagnetic radiation, photons) after the absorption of light. It is one form of luminescence (light emission) and is initiated by photoexcitation (excitation by photons). Toxic: Denotes a material that can damage living organisms due to the presence of phosphorus or heavy metals such as cadmium, lead, or mercury. Quantum Dot (QD): A nanoscale particle that exhibits size-dependent electronic and optical properties due to quantum confinement. The quantum dots disclosed herein preferably have at least one dimension less than about 50 nanometers. The disclosed quantum dots may be colloidal quantum dots, i.e., quantum dots that may remain in suspension when dispersed in a liquid medium. Some of the quantum dots which may be utilized in the compositions, systems and methodologies described herein are made from a binary semiconductor material having a formula MX, where M is a metal and X typically is selected from sulfur, selenium, tellurium, nitrogen, phosphorus, arsenic, antimony or mixtures thereof. Exemplary binary quantum dots which may be utilized in the compositions, systems and methodologies described herein include CdS, CdSe, CdTe, PbS, PbSe, PbTe, ZnS, ZnSe, ZnTe, InP, InAs, Cu2S, and In2S3. Other quantum dots which may be utilized in the compositions, systems and methodologies described herein are ternary, quaternary, and/or alloyed quantum dots including, but not limited to, ZnSexS1-x, ZnTexSe1-x, ZnTexS1-x, CdSexS1-x, CdTexSe1-x, CdTexS1-x, HgSexS1-x, HgTexSe1-x, HgTexS1-x, ZnCdS, ZnCdSe, ZnCdTe, ZnHgS, ZnHgSe, ZnHgTe, CdHgS, CdHgSe, CdHgTe, ZnCdSe_xS_2-x, ZnCdSe_xTe_2-x, ZnHgSe_xTe_2-x, ZnHgSe_xS_2-x, CdHgSe_xS_2-x, CdHgSeTe, CuAlS₂, CuInS₂, CuInSe₂, CuInTe₂,

4 LEGAL02/44543140v1 CuInGaSe2, CuInZnS2, CuZnSnSe2, CuInSexS2-x, CuInZnSexS2-x, (CuyAg1-y)InSexS2-x_, AgInS2, AgInSe2, and AgInSexS2-x quantum dots, where 0≤x≤2, although the use of non-toxic quantum dots is preferred. Embodiments of the disclosed quantum dots may be of a single material, or may comprise an inner core and an outer shell (e.g., a thin outer shell/layer formed by any suitable method, such as cation exchange). The quantum dots may further include a plurality of ligands bound to the quantum dot surface. Quantum Yield (QY): The ratio of the number of emitted photons to the number of absorbed photons for a fluorophore. Fluorophore: a material which absorbs a first spectrum of light and emits a second spectrum of light. Stokes shift: the difference in energy between the positions of the absorption shoulder or local absorption maximum and the maximum of the emission spectrum. Emission spectrum: Those portions of the electromagnetic spectrum over which a photoluminescent material exhibits photoluminescence (in response to excitation by a light source) whose amplitude is at least 1% of the peak PL emission. Polymer: A large molecule, or macromolecule, composed of many repeated subunits. Such polymers range from familiar synthetic plastics such as polystyrene or poly(methyl methacrylate) (PMMA), to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. One useful class of polymers are maleic anhydride grafted polymers where maleic anhydride can be grafted onto a suitable polymer backbone. The backbone for the grafting of the maleic anhydride is often a polyolefin (polyethylene, polypropylene, ethylene vinyl alcohol and the like) but could also be other types of polymers. Exemplary polymers include maleic anhydride-grafted polyethylene, maleic anhydride-grafted ethylene vinyl acetate, poly(methyl methacrylate) (PMMA), maleic anhydride grafted polyethylene vinyl alcohol, ethylene vinyl acetate (EVA), ethylene vinyl alcohol (EVOH), polyethylene vinyl alcohol (PVOH), polyamides such as nylon, polystyrene, ionoplasts, silicones, and epoxy resins.

5 LEGAL02/44543140v1 Self-absorption: The percentage of emitted light from a plurality of fluorophores that is absorbed by the same plurality of fluorophores. Some quantum dots, including CuInS2, CuInSe2, CuInGaSe₂, CuInZnS₂, CuZnSnSe₂, CuInSe_xS_2-x, CuInZnSe_xS_2-x, and AgInSe_xS_2-x, where 0≤x≤2, and related compounds, are known to have uniquely low self-absorption owing to the large Stokes shift between the absorption and emission spectrum of typically greater than 100 meV (~30 nm at 600 nm peak emission). DETAILED DESCRIPTION The urban built environment has the highest energy demand, thus the highest carbon footprint, yet the fewest opportunities for the integration of renewable energy generation. Many challenges associated with urban solar installation can be solved using BIPV technologies that can convert the façade of a building into electricity generation. The adoption of these systems at scale is challenging since traditional photovoltaic systems are not designed for a power generation system that is distributed through an entire building. Currently, off the shelf control electronics are designed only to operate on dedicated circuits, which excludes installations from using existing circuits in the building. The requirement to have dedicated circuits makes the installation of BIPV more complex and more costly than traditional roof top solar and has significantly limited the adoption of BIPV technologies. The impact of this proposal would be large. Currently the built environment accounts for estimates of 39.2% of total U.S. primary energy use, with electricity use accounting for 71.7% of building primary energy use. If implemented at scale, BIPV technologies would be able to provide a significant amount of sustainable electricity. For example, recently developed luminescent solar concentrator (LSC) windows with a shared load electrical system would support 20-30% of a building’s electrical consumption based on modeling performed by the National Renewable Energy Laboratory (NREL). In combination with a significant reduction in soft costs and balance of system costs, this solution would make urban solar more economically feasible than ever before.. Typical utility scale solar ties into the grid outside of urban environments, representing largest portion of current renewable energy generation. BIPV and power generating façade resembles the grid tie strategies of roof top solar. In the simplest case, without power storage and a charge control sub-circuit, the grid tie of power generators follows an add-on approach. First, power generating

6 LEGAL02/44543140v1 units are built and joined with a combiner and surge protector unit and sent to an Array DC disconnect. Then the combined collected electricity is inverted. Next, the energy produced is routed through a measuring sub-meter. And finally, the energy is routed to AC loads or the utility AC supply. Power generation products for utility and residential sectors are well supported to grid tie with products and service aimed towards a central tie in. To our knowledge, the application of power inversion technology has yet to be applied towards a BIPV or PV façade microgrid solution. The present invention is directed towards a distributed inverter system that would allow the power produced from a distributed system of BIPV devices located on the façade of a building, in the present case solar windows, to integrate directly into existing electrical systems by sharing existing electrical circuits. Figure 1 illustrates how traditional systems applied to a solar window installation would use microinverters for each modular solar window subunit that must all be interconnected using dedicated wiring and then are connected to a combiner box (usually with data storage and output functionality), followed by a safety disconnect switch and then the main electrical panel which has a dedicated system. While this does not add much complexity to a single rooftop system that the technology is designed for, a system of solar windows, or other BIPV technology, would require an immense amount of additional wiring and electrical design to include connection points on every part of the façade of a building of multiple stories all leading to a single connection to the grid. This becomes even more challenging in retrofit building projects, where additional circuits were not included in the original design. To solve this problem, as illustrated in Figure 1, the present system that consists of a specialized max power point tracking (MPPT) controller designed for one or multiple solar window/BIPV panel inputs with wide voltage and current ratings to provide additional flexibility for a wide variety of different building designs and sun exposures, an AC inverter, and a single-phase current monitoring sensor in series with the shared circuit. Specifically, this MPPT controller system includes a capable microcontroller, current and voltage sensors, as well as a shunt resistor to accurately record the array IV characteristics, a Wi-Fi communications module for IOT connectivity, and a high frequency isolated DC-DC converter with interleaved current. The MPPT system then provides the generated power to an optimized full bridge inverter (rated for photovoltaic rapid shutdown). The inverter portion can be a commercially available grid-tie microinverter for initial feasibility testing. Next

7 LEGAL02/44543140v1 the microinverter output is connected to a shared, existing circuit in the building using a junction box or outlet replacement that has a custom single-phase current monitoring sensor and amplifier/signal conditioning PCB in series with the distributed inverter shared circuit that feeds back to the MPPT controller which cuts power generation using a switch or reduces power generation through the programmable DC-DC converter on the circuit (with proper thermal dissipation) before the inverter. Some unique aspects of the present system are: A/C current monitoring PCB that quickly senses the single-phase current on the shared circuit before allowing generated power to enter the circuit (includes amplifier and other signal conditioning) (a 3-phase version is also possible) MPPT current sweep methodology for accurate power tracking and accurate power limiting Easily configured electrical system design inputs for customized installations, i.e., circuit breaker rating, single or double pole, panel current rating, number and type of circuit breakers per panel, number and type of shared load circuits per panel, safety margins, and other variables (for sub- panels and the like) Control logic that compares configurable inputs, distributed inverter shared circuit current, power generation and grid characteristics to cut or reduce power production to prevent circuit overload and islanding IOT functionality that provides data on both power generation, current, connections status, and more on each shared circuit in the electrical system and update capabilities. In addition, the microinverter system is designed to meet all current safety standards for PVRSE and will be the baseline for new standards for distributed solar inverters to be developed before being implemented on the grid. Globally, a net zero built environment is needed to combat anthropogenic climate change. A net zero city requires implementation of energy harvesting over all surfaces of a building. The BIPV field offers novel and advanced PV solutions for opaque and transparent curtainwall and the main obstacles facing their widespread adoption are installation complexity and cost. The presently described invention takes fundamental strides to commercialize a turnkey pathway for the adoption of all BIPV technologies on existing building circuitry. A building outfitted with

8 LEGAL02/44543140v1 a complete PV curtainwall can offset its own electricity requirements and depending on the building and the technologies implemented can be a net positive asset to the built environment. EXAMPLES The following examples are non-limiting and are merely intended to further illustrate the compositions, systems and methodologies described herein. EXAMPLE 1 Installation of inverter device within a building circuit without DC optimizer components. In a typical installation a quantity of 1-25 solar generating devices are grouped in an array with a total power rating of <250W are interconnected in series or parallel with or without the use of bypass or blocking diodes for each solar generating device generally not exceeding 60 VDC or 12 A per circuit. The array is then first directly connected to a shut off switch and second connected to the input of the inverter device. The inverter device can utilize max power point tracking and data collection (current and voltage) of the array using a current sweep control methodology and will have PVRSE functionality to allow for anti-islanding when the grid has lost power to protect individuals working on the circuit. Generally, the collected data can be communicated to a remote system level software system through WiFi communication protocols. In addition, the inverter device is installed with a shunt resistor or hall effect current sensor (Ammeter) including a signal conditioning circuit which is placed in series before all the devices on the circuit and provides signal values to the inverter. Based on the signal inputs (calibrated for each installation site) as well a multitude of configurable inputs based on the building electrical design such as circuit breaker rating, electrical panel rating, etc. and processed by a microcontroller, the inverter will control/throttle the amount of power generation provided to the existing circuit through a current limiting circuit, preventing possible overload of the existing circuit, panel, and building. In addition, the inverter assembly includes a sensor connected to the existing circuit to ensure proper phase matching typical of current microinverter..

9 LEGAL02/44543140v1 EXAMPLE 2 Installation of inverter device within a building circuit with DC optimizers In a typical installation a quantity of 1-25 solar generating devices with a total power rating of <250W are using multiple DC optimizers. The combination of the solar array and DC optimizers is first directly connected to a shut off switch and second, connected to the input of the inverter device. The device is capable of accurately sensing and logging installation DC voltage and current of the combined DC optimizer system. In addition, the inverter device is installed with a shunt resistor or hall effect current sensor (Ammeter) including a signal conditioning circuit which is placed in series before all the devices on the circuit and provides signal values to the inverter. Based on the signal inputs (calibrated for each installation site) as well a multitude of configurable inputs based on the building electrical design such as circuit breaker rating, electrical panel rating, etc. and processed by a microcontroller, the inverter will control/throttle the amount of power generation provided to the existing circuit, preventing possible overload of the existing circuit, panel, and building. In addition, the inverter assembly includes a sensor connected to the existing circuit to ensure proper phase matching typical of current microinverter products as well as sensing capabilities that ensure the device is compliant with current photovoltaic rapid shutdown equipment (PVRSE) regulations. EXAMPLE 3 Installation of multiple inverters devices in a building circuit A typical install of multiple inverters on a single existing circuit includes a current sensor (Ammeter) with signal conditioning with multiple outputs connected to each inverter in the circuit which is then connected to different individual building circuits. Generally, the number of inverters per circuit is driven by rated power which generally does not exceed 40% of the rated power for the circuit breaker when shared with additional outlets on the circuit or 80% of the rated power for circuit breaker when on a dedicated circuit. Typically, installations with multiple inverters per circuit include configurable inputs on for number or inverters within the circuit and their respective

10 LEGAL02/44543140v1 power rating to ensure combined load never exceeds 80% of the rated circuit power. In this example, the PCB electronics of the inverter can determine which building circuit to provide power to or limit current depending on the specific demands of the circuits it is connected to. EXAMPLE 4 Panel level installation of inverter system A typical panel level installation of an inverter system includes the use of backflow rating circuit breakers typically used for rooftop installations as well as a specialized panel or additional junction boxes that allow for the installation of current sensors in series with each inverter circuit as well asmultiple current sense wires that would travel within the circuit electrical conduit. Inputs within the control software for each inverter will include panel level power rating to electrical load across all circuits cannot exceed 80% of the rated panel power. EXAMPLE 5 Building level installation of inverter system A typical building level install will include an outdoor emergency shut off switch typical of photovoltaic hazard control systems (PVHCS) that will cut power to at least all inverter circuits within a building triggering the photovoltaic rapid shutdown device control device effectively cutting power generation on all inverter circuits within the building in the event of an emergency or maintenance. Inputs within the control software for each inverter will include building level power rating to ensure electrical load across all circuits and panels cannot exceed 80% of the rated building power. EXAMPLE 6 Building level installation of solar window coupled inverter system A typical building powered by solar windows leverages low-power units, typically less than 0.5- 20 W/ft2 or less than 200W per window unit. The voltages and powers involved are safer to handle

11 LEGAL02/44543140v1 than rooftop systems but not aligned with the high power AC grid that exists in the building. The inverter system described above can be used to condition the power from the solar windows to safely add power to the AC grid and enable safe electrical work when the AC grid goes down, thus enabling solar windows to leverage the buildings existing electrical system, namely the wiring. An exemplary solar window is based on luminescent solar concentrator glass that has quantum dot (QD) fluorophores having a large Stoke’s shift to harvest sunlight and transmit energy to edge- coupled PVs. These edge coupled PVs output DC energy typically in the range of 1-50 Volts and 0.1-10 Amps. The power output is highly dynamic based on the weather, position of the sun, shading from neighboring buildings or vegetation, and the power output can vary based on the window size. The inverter circuit needs to be capable of handling a wide range of input powers to be used in any building project. Exemplary QDs are based on CuInS2, CuInSe2, CuAlS2, AgInSe2, and ZnS semiconductors materials. These QDs are highly fluorescent, have large Stokes shifts, are stable, and relatively low cost. Exemplary glass windows use low-iron float glass, typically with less than 0.1% iron content to enhance waveguiding. EXAMPLE 7 Installation of inverter device within a building circuit or multiple circuits with high power output of solar generating device array In a typical installation of multiple solar generating devices are grouped in an array typically installed on the façade of a building with a total power rating of >250W are interconnected in series or parallel with or without the use of bypass or blocking diodes for each solar generating device that exceeds 60 VDC or 12 A per circuit. The array is then first directly connected to a shut off switch and second connected to the input of the inverter device. The inverter device can utilize max power point tracking and data collection (current and voltage) of the array using a current sweep control methodology. Generally, the collected data can be communicated to a remote system level software system through WiFi communication protocols. In addition, the inverter device is installed with a shunt resistor or hall effect current sensor (Ammeter) including a signal conditioning circuit which is placed in series before all the devices on a single circuit or multiple circuits and provides signal values to the inverter. Based on the signal inputs (calibrated for each installation site) as well a multitude of configurable inputs based on the building electrical design

12 LEGAL02/44543140v1 such as circuit breaker(s) rating(s), electrical panel rating, etc. and processed by a microcontroller, the inverter will control/throttle the amount of power generation provided to the existing circuit or multiple circuits, preventing possible overload of the existing circuit, panel, and building. In addition, the inverter assembly includes a sensor connected to the existing circuit to ensure proper phase matching typical of current microinverter products as well as sensing capabilities that ensure the device is compliant with current photovoltaic rapid shutdown equipment (PVRSE) regulations. EXAMPLE 8 Installation of multiple inverter devices in combination with a circuit divider component to distribute generated power from solar generating devices to multiple existing building circuit In this example installation, multiple solar generating devices generally generating 100W-1000W are interconnected in series or parallel and installed on top of or on the façade of a building. The array is then directed first into an electrical component that can divide and distribute power to inverter devices which are then connected to their own individual circuits located throughout the building. The electrical divider utilizes max power point tracking and data collection (current and voltage) of the array and a microcontroller reads the data collected. Each inverter device includes a current sensor (Ammeter) with signal conditioning that reads the load on the existing circuit. Inputs from the current sensor of the inverter device are communicated to the microcontroller and the microcontroller determines which circuits to distribute the power generated from the solar generating devices. The electrical divider is also equipped with a shut off switch that automatically closes if no current is measured from the inverter devices. Each inverter device is also compliant with current photovoltaic rapid shutdown equipment (PVRSE) regulations. EXAMPLE 9 Current sensors measuring electrical circuits in a building to determine when appliances or equipment are failing before complete failure In this example, current sensors placed on various existing circuits on a building or residence are used to provide data on each circuit to a microcontroller in order to monitor the health and viability of installed equipment. In general, equipment could include heating ventilation and air

13 LEGAL02/44543140v1 conditioning units, refrigerators, microwaves, electrical ovens, or any other semi-permeant electrical equipment. As installed equipment starts to fail, the equipment will draw more current to continue to operate. The microcontroller will analyze electrical circuits and detect when circuits are continuously drawing more power and warn an owner/operator through a mobile application that equipment on the circuit might be failing. Early detection of failing equipment will allow owners/operators to investigate and repair or replace equipment before they completely fail. Other abnormalities such as defective wiring/switches or other electrical components may also be identified and alerted to an owner/operator. Furthermore, owners/operators can identify circuits that should not have significant electrical load during certain hours of a day to identify when equipment is accidentally left on, such as lights, TVs, fans, heaters, air conditioning units, and manufacturing equipment. The user can then use software to turn off specific circuits as needed. EXAMPLE 10 Installation of DC-DC inverter device within a DC microgrid circuit An array of the solar generators is first directly connected to a shut off switch and second, connected to the input of the inverter device. The device is capable of accurately sensing and logging installation DC voltage and current of the solar array. In addition, the inverter device is installed with a shunt resistor or hall effect current sensor (Ammeter) including a signal conditioning circuit which is placed in series before all the devices on a DC microgrid circuit and provides signal values to the inverter. Based on the signal inputs (calibrated for each installation site) as well as a multitude of configurable inputs based on the building electrical design such as circuit breaker rating, electrical panel rating, etc. and processed by a microcontroller, the inverter will control/throttle the amount of power generation provided to the existing circuit, preventing possible overload of the existing circuit, panel, and building. In addition, the inverter assembly includes a sensor connected to the existing circuit to ensure proper phase matching typical of current microinverter products as well as sensing capabilities that ensure the device is compliant with current photovoltaic rapid shutdown equipment (PVRSE) regulations. Although the present invention has been described with reference to specific details, it is not intended that such details should be regarded as limitations upon the scope of the invention.

14 LEGAL02/44543140v1 Various modifications, substitutions, combinations, and ranges of parameters may be made or utilized in the compositions, and methodologies described herein, including as non-limiting examples: ^ controller that monitors circuit usage and production to identify when appliances/equip are failing and alerts the customer ^ An inverter with ammeter and power varying component located at the circuit breaker, which throttles the incoming AC power ^ An inverter system

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Claims

WHAT IS CLAIMED IS: 1. An electrical system, comprising several electronic components: a DC power source, a rapid DC power shutdown protection circuit, AC or DC grid sensing, and DC to AC or DC to DC power conversion.

2. The electrical system of claim 1, wherein said DC power source is a building-integrated photovoltaic, including but not limited to a solar window or solar module.

3. The electrical system of claim 1, wherein said AC grid is accessed via a building’s electrical outlet, from inside or outside of the wall, including by plugging into the wall outlet directly.

4. The electrical system of claim 1, wherein said DC power source operates between 1 and 50 V.

5. The electrical system of claim 1, wherein said AC grid operates between 51 and 250 V.

6. The electrical system of claim 1, wherein said DC power source is a quantum dot luminescent solar concentrator window.

7. The electrical system of claim 1, wherein said electrical components are printed onto a circuit board, or PCB.

8. The electrical system of claim 1, wherein said electrical components further includes sensors for monitoring the AC grid phase and frequency.

9. The electrical system of claim 1, wherein said DC to AC power conversion steps up the voltage of said DC power source to match the voltage of said AC grid.

10. The electrical system of claim 1, wherein said DC to AC power conversion matches the phase and frequency of said AC grid.

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11. The electrical system of claim 1, wherein said electrical components includes a maximum power point tracking feature for the DC power source.

12. The electrical system of claim 1, wherein said electrical system further includes a power storage, such as a battery.

13. The electrical system of claim 1, wherein said electrical system further includes quantum dots.

14. The electrical system of claim 1, wherein said electrical system can monitor circuits in a building to help diagnose early failure of equipment or appliances.

15. A grid-integrated photovoltaic array, comprising: a plurality of photovoltaic devices, maximum power point tracking, electrical coupling to the primary AC electrical system in a building, electrical power conditioning of the array output to match the building electrical power characteristics, and a rapid shutdown circuit.

16. The grid-integrated photovoltaic array of claim 14, wherein said primary AC electrical system is the same system that the wall outlets of the building are connected to.

17. The grid-integrated photovoltaic array of claim 14, wherein said photovoltaic array is an array of at least two electricity-generating windows.

18. The grid-integrated photovoltaic array of claim 14, wherein said building is retrofitted or renovated with said photovoltaic array after the building had already been constructed, and said primary AC electrical system is the existing electrical infrastructure of the building prior to retrofit or renovations.

19. The grid-integrated photovoltaic array of claim 14, wherein said photovoltaic array is an array of at least two electricity-generating windows that incorporate quantum dots.

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20. The electrical coupling of claim 14, wherein said electrical coupling includes a circuit that allows electricity generated from the said grid-integrated photovoltaic array to be distributed to different AC electrical circuits in the building depending on electricity demand.

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