Battery model with robustness to cloud-specific communication issues
A vehicle may include battery cells and a controller configured to control the vehicle, based on a state observation of the battery cells, using model parameters computed according to controller-determined cell nominal parameters adjusted by remotely-determined cell delta parameters, the delta parameters received from an external computing device responsive to cell measurements relating to a cell battery model sent to the external computing device, the delta parameters indicating adjustments that improve accuracy of the nominal parameters.
1. A vehicle comprising:
battery cells; and
a controller configured to control the vehicle, based on a state observation of the battery cells, using model parameters computed according to controller-determined cell nominal parameters adjusted by remotely-determined cell delta parameters, the delta parameters received from an external computing device responsive to cell measurements relating to a cell battery model sent to the external computing device, the delta parameters indicating adjustments that improve accuracy of the nominal parameters.
2. The vehicle of claim 1 , wherein the controller is further configured to estimate the nominal parameters according to a function of the cell measurements, and the cell measurements include cell voltage, cell current and cell temperature.
3. The vehicle of claim 1 , wherein each nominal parameter has an associated delta parameter, and the controller is further configured to identify each of the model parameters as one of (i) a sum of a nominal parameter and an associated delta parameter, and (ii) a product of the nominal parameter and the associated delta parameter.
4. The vehicle of claim 1 , wherein the battery model includes a battery equivalent circuit model, and the controller is further configured to perform the state observation to estimate battery state of charge (SOC).
5. The vehicle of claim 4 , wherein the measurements further include a previous estimate of battery SOC.
6. The vehicle of claim 4 , wherein the controller is further configured to compute an initial estimate of SOC according to ampere-hour integration.
7. A system comprising:
a computing device configured to
receive, from a vehicle via a communication network, battery cell measurements corresponding to a battery model of battery cells of the vehicle; and
send, to the vehicle via the communication network responsive to the measurements, cell delta parameters indicating adjustments to cell nominal parameters determined by the vehicle for the cells, the delta parameters indicating adjustments that improve accuracy of the nominal parameters.
8. The system of claim 7 , wherein the measurements include measurements of cell voltage, cell current and cell temperature.
9. The system of claim 7 , wherein the battery model includes a battery equivalent circuit model configured to supply battery equivalent circuit model parameters to estimate a battery state of charge (SOC).
10. The system of claim 9 , wherein the measurements further include a previous estimate of battery SOC.
11. The system of claim 7 , wherein the computing device is further configured to
estimate the nominal parameters according to a function of the cell measurements; and
compute the cell delta parameters as a difference of model parameters identified according to a battery equivalent circuit model and the nominal parameters.
12. The system of claim 7 , wherein the computing device is further configured to compute the cell delta parameters according to direct identification of model parameters identified according to a battery equivalent circuit model.
13. A method comprising:
controlling a vehicle by a controller, based on a state observation of battery cells, using model parameters computed according to controller-determined cell nominal parameters adjusted by remotely-determined cell delta parameters, the delta parameters received by the controller from an external computing device responsive to cell measurements relating to a battery model sent to the computing device, the delta parameters indicating adjustments that improve accuracy of the nominal parameters.
14. The method of claim 13 , further comprising estimating the nominal parameters according to a function of the cell measurements, the cell measurements including cell voltage, cell current and cell temperature.
15. The method of claim 13 , wherein each nominal parameter has an associated delta parameter, and further comprising identifying each of the model parameters as one of (i) a sum of a nominal parameter and an associated delta parameter, and (ii) a product of the nominal parameter and the associated delta parameter.
16. The method of claim 13 , wherein the battery model includes a battery equivalent circuit model, and further comprising performing the state observation to estimate battery state of charge (SOC).
17. The method of claim 13 , wherein the measurements further include a previous estimate of battery SOC.
18. The method of claim 13 , further comprising computing an initial estimate of SOC according to ampere-hour integration.