# US 7,652,394 B2 · Responsive electricity grid substation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,652,394 B2 - Document ID: US7652394B2 - Status: Granted - Kind: B2 - Application number: 10/578,597 - Filed: 2004-11-04 - Published: 2007-08-02 - Granted: 2010-01-26 - Earliest claimed: 2003-11-07 - Assignees: Responsiveload Limited - Inventors: David Hirst - Web page: https://patentgrep.com/patent/US7652394B2 ## CPC - H02J 3/06: Controlling the transfer of power between connected networks; Controlling load sharing between connected networks - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract There is provided an electricity grid, system having a substation connecting two grid parts, preferably at different levels in the grid hierarchy, wherein flow control means is provided for controlling the flow of electricity between the two parts in dependence on the level of stress of the respective grid part of the network. ## Claims ### Claim 1 A substation of an electricity grid system, the substation connecting two grid parts operating at different frequencies and/or voltage levels, the substation comprising means for monitoring a parameter indicative of the electricity available from and/or the electricity required by the two grid parts and responsive flow control means for controlling the flow of electricity between the two grid parts in response to the parameter of the two grid parts, characterized in that said means for monitoring is configured to derive the parameter of one or both of the grid parts from an integration of a frequency of said one or both of the grid parts since a reset point. ### Claim 2 (depends on 1) The substation of claim 1, wherein the frequency is monitored as an absolute frequency value. ### Claim 3 (depends on 1) The substation of claim 1, wherein the frequency is monitored as a measure of frequency deviation from a normal operating frequency, said normal operating frequency being the frequency when the respective grid part is not under stress. ### Claim 4 (depends on 1) The substation of claim 1, further comprising means for modulating the flow of electricity between the two grid parts to bring the AC phases of the two grid parts closer to matching one another. ### Claim 5 (depends on 4) The substation of claim 4, wherein the means for bringing the AC phases closer to matching one another comprises a switch. ### Claim 6 (depends on 1) The substation of claim 1, wherein said parameter of one or both of the grid parts comprises a signal indicative of an imbalance between the electricity available and electricity required by said one or both of the grid parts. ### Claim 7 (depends on 1) The substation of claim 1, wherein said parameter is a value parameter indicative of the value of electricity to said one or both of the grid parts. ### Claim 8 (depends on 7) A substation as claimed in claim 7, wherein the value parameter comprises a monetary price value. ### Claim 9 (depends on 8) A substation as claimed in claim 8, wherein said monetary price is variable in dependence on the frequency of the one of the grid parts or both of the grid parts. ### Claim 10 (depends on 1) The substation of claim 1, further comprising a clock driven by the frequency of said one or both grid parts, a clock driven by a grid nominal frequency and a clock comparator for comparing the clocks. ### Claim 11 (depends on 1) The substation of claim 1, further comprising at least one electricity flow meter for metering electricity flow between the two grid parts. ### Claim 12 (depends on 1) The substation of claim 1, further comprising means for detecting a rate of change of the frequency of one or both grid parts, said means for controlling configured to control the flow of electricity in response to the rate of change detected. ### Claim 13 (depends on 1) An electricity supply grid system comprising two grid parts connected by the substation of claim 1, wherein each grid part comprises one or more loads and a management unit for providing said parameter. ### Claim 14 (depends on 13) The electricity supply grid system of claim 13, said management unit for regulating the consumption of electricity by said one or more loads in dependence on the frequency of the respective grid part. ### Claim 15 (depends on 14) The substation of claim 14, wherein said parameter is a value parameter indicative of the value of electricity to said one or both of the grid parts and one of the grid parts is an electricity generator, said generator configured to increase or decrease its electricity output in dependence on said value parameter. ### Claim 16 (depends on 14) The substation of claim 14, wherein said parameter is a value parameter indicative of the value of electricity to said one or both of the grid parts and one of the grid parts is an electricity consuming device, said consuming device configured to increase or decrease its consumption in dependence on said value parameter. ### Claim 17 (depends on 2) The substation of claim 2, further comprising means for modulating the flow of electricity between the two grid parts to bring the AC phases of the two grid parts closer to matching one another. ### Claim 18 (depends on 3) The substation of claim 3, further comprising means for modulating the flow of electricity between the two grid parts to bring the AC phases of the two grid parts closer to matching one another. ### Claim 19 (depends on 17) The substation of claim 17, wherein said parameter is a value parameter indicative of the value of electricity to said one or both of the grid parts and one of the grid parts is an electricity generator, said generator configured to increase or decrease its electricity output in dependence on said value parameter. ### Claim 20 (depends on 17) The substation of claim 17, wherein said parameter is a value parameter indicative of the value of electricity to said one or both of the grid parts and one of the grid parts is an electricity consuming device, said consuming device configured to increase or decrease its consumption in dependence on said value parameter.