ESTIMATION AND COMPENSATION OF BATTERY MEASUREMENT AND ASYNCHRONIZATION BIASES

摘要

A hybrid or electric vehicle includes a traction battery to store and provide energy for the vehicle. The traction battery includes a number of battery cells. For effective operation of the traction battery, operating parameters, such as state of charge and battery power limits, may need to be known. The operating parameters may be a function of battery cell voltage and impedance parameters. A parameter estimation scheme may use measured cell voltages and a measured traction battery current as inputs. A current measurement bias may be modeled that incorporates measurement bias caused by asynchronous current and voltage measurements. The current measurement bias may be estimated for each cell and the value may differ between cells.

主权项

1. A vehicle comprising:
a traction battery including a plurality of cells; and a controller programmed to implement a state estimator configured to estimate, for each cell, a current measurement bias specific to the cell that depends on a temporal difference between current and voltage measurements for the cell, and operate the traction battery according to battery power limits derived from voltage parameters that are based on the current measurement bias, wherein at least some of the current measurement biases have different values.