# US 9,882,386 B2 · Consensus-based distributed cooperative control for microgrid voltage regulation and reactive power sharing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,882,386 B2 - Document ID: US9882386B2 - Status: Granted - Kind: B2 - Application number: 14/693,585 - Filed: 2015-04-22 - Published: 2015-10-29 - Granted: 2018-01-30 - Earliest claimed: 2014-04-23 - Assignees: NEC Corporation - Applicants: NEC Laboratories America, Inc. - Inventors: Dawei He; Ratnesh Sharma; Di Shi - Web page: https://patentgrep.com/patent/US9882386B2 ## CPC - H02J 3/16: by adjustment of reactive power - H02J 3/46: Controlling the sharing of generated power between the generators, sources or networks - H02J 3/48: Controlling the sharing of active power - H02J 3/50: Controlling the sharing of reactive power - H02J 2103/30: Simulating, planning, modelling, reliability check or computer assisted design [CAD] of electric power networks - Y02E 40/30: Reactive power compensation - Y02E 60/00: Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation - 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 - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - 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 A controller used in microgrid systems that includes a primary control module and a secondary control module. The primary control module may employ a primary consensus control to control at least one of a real power and reactive power sharing in at least one distributed generator system of a microgrid. The secondary control module may employ a secondary consensus control to maintain at least one of voltage and frequency in the microgrid to a nominal value. ## Claims ### Claim 1 A controller used in microgrid systems comprising: a primary control module configured to employ a primary consensus control including at least one hardware processor to control at least one of a real power and reactive power sharing in at least one distributed generator of a microgrid, wherein the primary consensus control exchanges reactive power information between each neighboring distributed generator in the microgrid so that said each distributed generator has a proportion of total power in the microgrid; wherein the primary consensus control comprises a control algorithm: where {dot over (V)}i is a magnitude of output voltage for an ith distributed generator, Ni is neighboring buses of bus i, Qj reactive power output at a jth distributed generator, Qi reactive power output at an ith distributed generator, Dq,i is the multiplicative inverse of the reactive power droop coefficient for the ith distributed generator, and Dq,j is the multiplicative inverse of the reactive power droop coefficient for the jth distributed generator; and a secondary control module configured to employ a secondary consensus control to maintain at least one of voltage and frequency in the microgrid to a nominal value. ### Claim 2 (depends on 1) The controller of claim 1, wherein the primary consensus control is integrated into a reactive power voltage (Q-V) droop control. ### Claim 3 (depends on 1) The controller of claim 1, wherein the primary consensus control exchanges said reactive power information between said each distributed generator of the microgrid and a neighboring distributed generator of the microgrid to ensure that said reactive power sharing between said each distributed generator of the microgrid is exact so that each distributed generator within the microgrid has an equal proportion of said total power of the microgrid. ### Claim 4 (depends on 1) The controller of claim 1, wherein the primary consensus control exchanges a droop coefficient of each distributed generator and a neighboring distributed generator of the microgrid. ### Claim 5 (depends on 1) The controller of claim 1, wherein the at least one distributed generator of a microgrid causes fluctuation of the voltage and frequency in the microgrid, and the secondary consensus control restores at least one of voltage and frequency in the microgrid to said nominal value that is preset. ### Claim 6 (depends on 1) The controller of claim 1, wherein the secondary control module exchanges voltage information at each distributed generator with its neighboring distributed generator within the microgrid. ### Claim 7 (depends on 1) The controller of claim 1, wherein the secondary consensus control comprises a consensus control signal: V . ref , i = V . i + δ ⁢ V . i , ⁢ V . ref , i = ∑ j ∈ N i ⁢ ⁢ ( Q j D q , j - Q i D q , i ) + ∑ j ∈ N i ⁢ ⁢ ( δ ⁢ ⁢ V j - δ ⁢ ⁢ V i ) + b i ⁡ ( δ ⁢ ⁢ V - δ ⁢ ⁢ V i ) wherein Vi is a magnitude of output voltage of the ith distributed generator (DG), Dq,j is a multiplicative inverse of the reactive power droop coefficient for the jth DG, Dq,i is a multiplicative inverse of the reactive power droop coefficient for the ith DG, Vref is a nominal voltage of the microgrid, δV is a secondary control signal, δVi is a local secondary control variable whose dynamics is designed to track the central secondary control signal δV, and bi is binary variable indicating whether node i is a leading node in the consensus network. ### Claim 8 (depends on 1) The controller of claim 1, wherein the controller employs virtual impedance to adjust line R/X (line resistance/line reactance) influences and mitigate asymmetrical line impedance. ### Claim 9 A method for controlling a microgrid system comprising: controlling at least one of real power and reactive power amongst distributed generators of a microgrid using a primary consensus control employing at least one hardware processor to exchange reactive power information between each neighboring distributed generator of the microgrid so that each distributed generator has a proportion of total power in the microgrid; wherein the primary consensus control comprises a control algorithm: where {dot over (V)}i is a magnitude of output voltage for an ith distributed generator, Ni is neighboring buses of bus i, Qj reactive power output at a jth distributed generator, Qi reactive power output at an ith distributed generator, Dq,i is the multiplicative inverse of the reactive power droop coefficient for the ith distributed generator, and Dq,j is the multiplicative inverse of the reactive power droop coefficient for the jth distributed generator; and maintaining a nominal value of at least one of voltage and frequency in the microgrid using a secondary consensus control. ### Claim 10 (depends on 9) The method of claim 9, wherein the distributed generators comprise hydro power, biomass or biogas power, wind power, geothermal power, cogeneration using steam turbines, natural gas-fired power, fuel cells, micro-turbines or reciprocating engines to turn generators or combinations thereof. ### Claim 11 (depends on 9) The method of claim 9, wherein the primary consensus control is integrated into a reactive power voltage (Q-V) droop control. ### Claim 12 (depends on 9) The method of claim 9, wherein the primary consensus control exchanges the reactive power information between each neighboring distributed generator of the microgrid to ensure that reactive power sharing between said each distributed generator of the microgrid is exact so that each distributed generator within the microgrid has an equal proportion of total power. ### Claim 13 (depends on 9) The method of claim 9, wherein the primary consensus control exchanges a droop coefficient of each distributed generator and a neighboring distributed generator of the microgrid. ### Claim 14 (depends on 9) The method of claim 9, wherein the at least one distributed generator of a microgrid causes fluctuation of the voltage and frequency in the microgrid, and the secondary consensus control restores at least one of voltage and frequency in the microgrid to said nominal value that is preset. ### Claim 15 (depends on 9) The method of claim 9, wherein the secondary control module exchanges voltage information at each distributed generator with its neighboring distributed generator within the microgrid. ### Claim 16 A computer program product is provided that includes a non-transitory computer readable storage medium having computer readable program code embodied therein for a method of controlling a microgrid system, the method comprising: controlling at least one of real power and reactive power amongst distributed generators of a microgrid using a primary consensus control employing at least one hardware processor to exchange reactive power information between each neighboring distributed generator of microgrid so that each distributed generator has a proportion of total power in the microgrid; wherein the primary consensus control comprises a control algorithm: where {dot over (V)}i is a magnitude of output voltage for an ith distributed generator, Ni is neighboring buses of bus i, Qj reactive power output at a jth distributed generator, Qi reactive power output at an ith distributed generator, Dq,i is the multiplicative inverse of the reactive power droop coefficient for the ith distributed generator, and Dq,j is the multiplicative inverse of the reactive power droop coefficient for the jth distributed generator; and maintaining a nominal value of at least one of voltage and frequency in the microgrid using a secondary consensus control. ### Claim 17 (depends on 16) The computer program product of claim 16, wherein the primary consensus control exchanges reactive power information between each distributed generator of the microgrid and a neighboring distributed generator of the microgrid to ensure that reactive power sharing between said each distributed generator of the microgrid is exact so that each distributed generator within the microgrid has an equal proportion of total power. ### Claim 18 (depends on 16) The computer program product of claim 16, wherein the primary consensus control is integrated into a reactive power voltage (Q-V) droop control. ### Claim 19 (depends on 16) The computer program product of claim 16, wherein the secondary control module exchanges voltage information at each distributed generator with its neighboring distributed generator within the microgrid.