# US 2021/0281069 A1 · Photovoltaic grid capacity sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0281069 A1 - Document ID: US20210281069A1 - Status: Published application - Kind: A1 - Application number: 17/185,248 - Filed: 2021-02-25 - Published: 2021-09-09 - Earliest claimed: 2020-03-03 - Assignees: Massachusetts Institute of Technology - Applicants: Massachusetts Institute of Technology - Inventors: Brice MacLaren; James Macomber; Megan Richardson - Web page: https://patentgrep.com/patent/US20210281069A1 ## CPC - H02J 3/003: {Load forecast, e.g. methods or systems for forecasting future load demand} - H02J 3/32: using batteries or super capacitors with converting means - H02J 3/0012: characterised by the contingency detection means in AC networks, e.g. using phasor measurement units [PMU], synchrophasors or contingency analysis - H02J 7/663: {using battery or load disconnect circuits (H02J9/002 takes precedence)} - H02J 13/12: Monitoring network conditions, e.g. electrical magnitudes or operational status - H02J 2101/24: Photovoltaics - H02J 2103/30: Simulating, planning, modelling, reliability check or computer assisted design [CAD] of electric power networks - H02J 2105/10: Local stationary networks having a local or delimited stationary reach - H02J 2207/30: Charge provided using DC bus or data bus of a computer - 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) - Y02E 10/56: Power conversion systems, e.g. maximum power point trackers - Y02E 40/70: Smart grids as climate change mitigation technology in the energy generation sector - Y02E 60/00: Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation - Y02E 70/30: Systems combining energy storage with energy generation of non-fossil origin - Y02P 80/20: using renewable energy - Y04S 10/123: the energy generation units being or involving renewable energy sources - Y04S 10/30: State monitoring, e.g. fault, temperature monitoring, insulator monitoring, corona discharge - Y04S 20/12: Energy storage units, uninterruptible power supply [UPS] systems or standby or emergency generators, e.g. in the last power distribution stages - Y04S 40/20: Information technology specific aspects, e.g. CAD, simulation, modelling, system security - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS - Y04S: SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS ## Abstract In one aspect, a method to determine a capacity of a microgrid includes applying a current test load to the microgrid and measuring a current through an energy storage device, the current indicating a charging status of the energy storage device based on a current load being applied to the microgrid through activated power outlets being served by the microgrid and the current test load, the energy storage device being integrated with the microgrid. The method also includes, responsive to a determination that the measured current based on the current load being applied to the microgrid and the current test load indicates that the energy storage device is discharging, determining the capacity of the microgrid, wherein the capacity is the current load being applied to the microgrid through activated power outlets and a test load applied to the microgrid immediately preceding the current test load. ## Claims ### Claim 1 A system to determine a capacity of a microgrid, the system comprising: one or more non-transitory machine-readable mediums configured to store instructions; and one or more processors configured to execute the instructions stored on the one or more non-transitory machine-readable mediums, wherein execution of the instructions causes the one or more processors to apply a current test load to the microgrid; measure a current through an energy storage device, the current indicating a charging status of the energy storage device based on a current load being applied to the microgrid through activated power outlets being served by the microgrid and the current test load, the energy storage device being integrated with the microgrid; and responsive to a determination that the measured current based on the current load being applied to the microgrid and the current test load indicates that the energy storage device is discharging, determine the capacity of the microgrid, wherein the capacity is the current load being applied to the microgrid through activated power outlets and a test load applied to the microgrid immediately preceding the current test load. ### Claim 2 (depends on 1) The system of claim 1, wherein execution of the instructions causes the one or more processors to, responsive to a determination that the measured current based on the current load being applied to the microgrid and the current test load indicates that the energy storage device is charging, apply an increased test load to the microgrid, the increased test load being an increase over the current test load. ### Claim 3 (depends on 2) The system of claim 2, wherein execution of the instructions causes the one or more processors to, responsive to a determination that the measured current based on the current load being applied to the microgrid and the increased test load indicates that the energy storage device is discharging, determine the capacity of the microgrid, wherein the capacity is the current load being applied to the microgrid and the current test load that immediately preceded the increased test load. ### Claim 4 (depends on 3) The system of claim 3, wherein execution of the instructions causes the one or more processors to, responsive to a determination that the determined capacity of the microgrid is less than an expected maximum power draw through the activated power outlets, shed a load being served by the microgrid, wherein the load being served by the microgrid is the expected maximum power draw through the activated power outlets. ### Claim 5 (depends on 1) The system of claim 1, wherein execution of the instructions causes the one or more processors to, responsive to a determination that the determined capacity of the microgrid is less than an expected maximum power draw through the activated power outlets, shed a load being served by the microgrid. ### Claim 6 A system to determine a capacity of a microgrid, the system comprising: means for applying a test load to the microgrid; means for measuring a current through an energy storage device, the current indicating a charging status of the energy storage device based on a current load being applied to the microgrid through activated power outlets being served by the microgrid and the test load, the energy storage device being integrated with the microgrid; and means, responsive to a determination that the measured current based on the current load being applied to the microgrid through the activated power outlets being served by the microgrid and the test load indicates that the energy storage device is discharging, for determining the capacity of the microgrid. ### Claim 7 (depends on 6) The system of claim 6, further comprising, means, responsive to a determination that the measured current based on the current load being applied to the microgrid and the test load indicates that the energy storage device is charging, for increasing the test load that is being applied to the microgrid. ### Claim 8 A method to determine a capacity of a microgrid, the method comprising: applying a current test load to the microgrid; measuring a current through an energy storage device, the current indicating a charging status of the energy storage device based on a current load being applied to the microgrid through activated power outlets being served by the microgrid and the current test load, the energy storage device being integrated with the microgrid; and responsive to a determination that the measured current based on the current load being applied to the microgrid and the current test load indicates that the energy storage device is discharging, determining the capacity of the microgrid, wherein the capacity is the current load being applied to the microgrid through activated power outlets and a test load applied to the microgrid immediately preceding the current test load. ### Claim 9 (depends on 8) The method of claim 8, further comprising, responsive to a determination that the measured current based on the current load being applied to the microgrid and the current test load indicates that the energy storage device is charging, applying an increased test load to the microgrid, the increased test load being an increase over the current test load. ### Claim 10 (depends on 9) The method of claim 9, further comprising, responsive to a determination that the measured current based on the current load being applied to the microgrid and the increased test load indicates that the energy storage device is discharging, determining the capacity of the microgrid, wherein the capacity is the current load being applied to the microgrid and the current test load that immediately preceded the increased test load. ### Claim 11 (depends on 10) The method of claim 10, further comprising, responsive to a determination that the determined capacity of the microgrid is less than an expected maximum power draw through the activated power outlets, shedding a load being served by the microgrid, wherein the load being served by the microgrid is the expected maximum power draw through the activated power outlets. ### Claim 12 (depends on 11) The method of claim 11, wherein shedding the load being served by the microgrid includes deactivating an activated power outlet. ### Claim 13 (depends on 11) The method of claim 11, wherein shedding the load being served by the microgrid includes deactivating an active Universal Serial Bus (USB) outlet. ### Claim 14 (depends on 8) The method of claim 8, further comprising, responsive to a determination that the determined capacity of the microgrid is less than an expected maximum power draw through the activated power outlets, shedding a load being served by the microgrid. ### Claim 15 (depends on 14) The method of claim 14, wherein shedding the load being served by the microgrid includes deactivating an activated power outlet. ### Claim 16 (depends on 15) The method of claim 15, wherein deactivating an activated power outlet is based on a priority. ### Claim 17 (depends on 14) The method of claim 14, wherein shedding the load being served by the microgrid includes deactivating an activated power outlet that is not drawing power. ### Claim 18 (depends on 14) The method of claim 14, wherein shedding the load being served by the microgrid includes deactivating an active Universal Serial Bus (USB) outlet. ### Claim 19 (depends on 8) The method of claim 8, further comprising: responsive to a determination that the determined capacity of the microgrid is at least an expected maximum power draw through the activated power outlets, determining an excess capacity of the microgrid, wherein the excess capacity is the capacity of the microgrid in excess of an expected maximum power draw through the activated power outlets; and responsive to a determination that the excess capacity is at least a maximum expected power draw through the inactive power outlet, activating the inactive power outlet. ### Claim 20 (depends on 8) The method of claim 8, wherein the microgrid is a photovoltaic (PV) microgrid.