# US 10,502,789 B2 · Method and device for determining a parameter of a model of a technical installation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,502,789 B2 - Document ID: US10502789B2 - Status: Granted - Kind: B2 - Application number: 14/303,531 - Filed: 2014-06-12 - Published: 2014-12-18 - Granted: 2019-12-10 - Earliest claimed: 2013-06-12 - Assignees: Infineon Technologies AG - Applicants: Infineon Technologies AG - Inventors: Michael Lunglmayr; Stefano Marsili; Christoph Unterrieder - Web page: https://patentgrep.com/patent/US10502789B2 ## CPC - G01R 31/367: Software therefor, e.g. for battery testing using modelling or look-up tables - G01R 31/387: Determining ampere-hour charge capacity or SoC - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract Methods and devices for determining at least one parameter of a model of a technical installation are provided. In this case, the parameters are updated on the basis of measurements as a function of an observation matrix. The observation matrix is prescribed as a function of the model and being able, if appropriate, to depend on a time variable which can be measured. ## Claims ### Claim 1 A method comprising: performing a plurality of terminal voltage measurements of a battery in a low load condition; using an evaluation device, estimating at least one parameter of a model that describes a relaxation of a terminal voltage of the battery over time based on the plurality of terminal voltage measurements, wherein estimating the at least one parameter comprises initializing at least one parameter at a prescribed value, and for each of the plurality of terminal voltage measurements, determining a model-based estimate of the terminal voltage as a function of a previous value of the at least one parameter and of at least one part of an observation matrix, the observation matrix being an observation matrix prescribed as a function of the model; determining an error value as a function of the model-based estimate of the terminal voltage and of a current terminal voltage measurement of the plurality of terminal voltage measurements, and determining an updated value of the at least one parameter as a function of the previous value of the at least one parameter, of the error value and of the at least one part of the observation matrix; after estimating the at least one parameter, estimating a relaxed terminal voltage based on the at least one parameter, the relaxed terminal voltage representing a future value of an open circuit voltage of the battery when the battery is completely relaxed; and determining a charging state of the battery based on the estimated relaxed terminal voltage. ### Claim 2 (depends on 1) The method as claimed in claim 1, wherein the observation matrix has components dependent on a time variable. ### Claim 3 (depends on 2) The method as claimed in claim 2, wherein the time variable is measured in order to determine the at least one part of the observation matrix. ### Claim 4 (depends on 1) The method as claimed in claim 1, wherein the determination of the estimate is undertaken in accordance with ŷ[n]=h[n]θ[n−1], ŷ[n] being the model-based estimate of the terminal voltage, h[n] being an nth row of the observation matrix, n being a time parameter which denotes a number of a pass of the determination of the estimate, of the determination of the error value and of the updating of the parameters, and θ[n−1] denoting a vector with values of the at least one parameter in a previous pass, the error value being determined in accordance with e[n]=y[n]−ŷ[n], e[n] denoting the error value and y[n] denoting the current terminal voltage measurement of the plurality of terminal voltage measurements, and the parameters being updated in accordance with θ[n]=θ[n−1]+2μh[n]e[n] μ denoting a step width. ### Claim 5 (depends on 1) The method as claimed in claim 1, wherein the model is described by V t = V ∞ - Γ ⁢ ⁢ γ t α ⁢ log δ ⁡ ( t ) ⁢ exp ⁡ ( ɛ t 2 ) , Vt being the terminal voltage at time t, V∞ being a model parameter, and γ, α and δ being parameters to be estimated, ε being an error parameter, and Γ being set at + or 1 as a function of whether the battery was previously charged or discharged, the model being transformed into a linear problem in order to carry out the method. ### Claim 6 (depends on 5) The method as claimed in claim 5, wherein the determination of the estimate is undertaken in accordance with ŷ[n]=h[n]θ[n−1], ŷ[n] being the model-based estimate of the terminal voltage, h[n] being an nth row of the observation matrix, n being a time parameter which denotes a number of a pass of the determination of the estimate, of the determination of the error value and of the updating of the parameters, and θ[n−1] denoting a vector with values of the at least one parameter in a previous pass, the error value being determined in accordance with e[n]=y[n]−ŷ[n], e[n] denoting the error value and y[n] denoting the current terminal voltage measurement of the plurality of terminal voltage measurements, and the parameters being updated in accordance with θ[n]=θ[n−1]+2μh[n]e[n], μ denoting a step width; and wherein it holds that ŷ[n]=log({circumflex over (V)}∞,n−Vt,n)2 h[n]=[1,log(n),log(log(n))] θ[n]=[C,A,D], {circumflex over (V)}∞,n being an estimate of the model parameter V∞ in an nth time step, Vt,n being a terminal voltage measurement of the plurality of voltage measurements in the nth time step, C=2×log(γ), A=−2×α and D=−2×δ. ### Claim 7 (depends on 1) The method as claimed in claim 1, wherein the low load condition is a condition in which a load is separated from the battery. ### Claim 8 (depends on 1) The method as claimed in claim 1, wherein the evaluation device comprises a processor. ### Claim 9 (depends on 1) The method as claimed in claim 1, wherein the evaluation device comprises dedicated hardware. ### Claim 10 (depends on 1) The method as claimed in claim 1, further comprising recharging the battery when the determined charging state indicates a high degree of discharge. ### Claim 11 (depends on 10) The method as claimed in claim 10, wherein recharging the battery comprises activating a generator coupled to the battery. ### Claim 12 (depends on 11) The method as claimed in claim 11, wherein activating the generator comprises starting an auxiliary motor that drives the generator. ### Claim 13 A device comprising: a voltmeter configured to measure a plurality of terminal voltage measurements of a battery in a low load condition; and an evaluation device configured to estimate at least one parameter of a model that describes a relaxation of a terminal voltage of the battery over time based on the plurality of terminal voltage measurements by initializing at least one parameter at a prescribed value, and for each of the plurality of terminal voltage measurements, determining a model-based estimate of the terminal voltage as a function of a previous value of the at least one parameter and at least one part of an observation matrix, the observation matrix being an observation matrix prescribed as a function of the model, determining an error value as a function of the model-based estimate of the terminal voltage and a current terminal voltage measurement of the plurality of terminal voltage measurements, and determining an updated value of the at least one parameter as a function of the previous value of the at least one parameter, of the error value and of the at least one part of the observation matrix, wherein the device is configured, after the at least one parameter is estimated, to estimate a relaxed terminal voltage based on the at least one parameter, the relaxed terminal voltage representing a future value of an open circuit voltage of the battery when the battery is completely relaxed, and determine a charging state of the battery based on the estimated relaxed terminal voltage. ### Claim 14 (depends on 13) The device as claimed in claim 13, wherein the observation matrix has components dependent on a time variable. ### Claim 15 (depends on 14) The device as claimed in claim 14, wherein the voltmeter is configured to measure the time variable. ### Claim 16 (depends on 13) The device as claimed in claim 13, wherein the evaluation device is set up to determine the estimate in accordance with ŷ[n]=h[n]θ[n−1] ŷ[n] being the model-based estimate of the terminal voltage, h[n] being an nth row of the observation matrix, n being a time parameter which denotes a number of a pass of the determination of the estimate, of the determination of the error value and of the updating of the parameters, and θ[n−1] denoting a vector with values of the at least one parameter in a previous pass, to determine the error value in accordance with e[n]=y[n]−ŷ[n] e[n] denoting the error value and y[n] denoting the current terminal voltage measurement of the plurality of terminal voltage measurements, and the parameters being updated in accordance with, θ[n]=θ[n−1]+2μh[n]e[n] μ denoting a step width. ### Claim 17 (depends on 13) The device as claimed in claim 13, wherein the model is described by V t = V ∞ - Γ ⁢ ⁢ γ t α ⁢ log δ ⁡ ( t ) ⁢ exp ⁡ ( ɛ t 2 ) , Vt being the terminal voltage at time t, V∞ being a model parameter, and γ, α and δ being parameters to be estimated, ε being an error parameter, and Γ being set at + or 1 as a function of whether the battery was previously charged or discharged, the model being transformed into a linear problem. ### Claim 18 (depends on 17) The device as claimed in claim 17, wherein the evaluation device is set up to determine the estimate in accordance with ŷ[n]=h[n]θ[n−1], ŷ[n] being the model-based estimate of the terminal voltage, h[n] being an nth row of the observation matrix, n being a time parameter which denotes a number of a pass of the determination of the estimate, of the determination of the error value and of the updating of the parameters, and θ[n−1] denoting a vector with values of the at least one parameter in a previous pass, to determine the error value in accordance with e[n]=y[n]−ŷ[n], e[n] denoting the error value and y[n] denoting the current terminal voltage measurement of the plurality of terminal voltage measurements, and the parameters being updated in accordance with, θ[n]=θ[n−1]+2μh[n]e[n], μ denoting a step width; and wherein it holds that ŷ[n]=log({circumflex over (V)}∞,n−Vt,n)2 h[n]=[1,log(n),log(log(n))] θ[n]=[C,A,D], {circumflex over (V)}∞,n being an estimate of the model parameter V∞ in an nth time step, Vt,n being a terminal voltage measurement of the plurality of voltage measurements in the nth time step, C=2×log(γ),A=−2×α and D=−2×δ. ### Claim 19 (depends on 13) The device as claimed in claim 13, wherein the low load condition is a condition in which a load is separated from the battery. ### Claim 20 (depends on 13) The device as claimed in claim 13, wherein the evaluation device comprises a processor. ### Claim 21 (depends on 13) The device as claimed in claim 13, wherein the evaluation device comprises dedicated hardware. ### Claim 22 (depends on 18) The device of claim 18, wherein the device is further configured, after the at least one parameter is estimated, to cause the battery to be recharged when the determined charging state indicates a high degree of discharge. ### Claim 23 (depends on 22) The device of claim 22, wherein the evaluation device is configured to charge the battery by activating a generator coupled to the battery. ### Claim 24 (depends on 23) The device of claim 23, wherein activating the generator comprises starting an auxiliary motor that drives the generator.