A method of controlling a traction control system (30) includes
continuously adapting a steady state driven wheel speed to reference
wheel speed ratio, so that said traction control system can avoid
unnecessary actuations (e.g., demanding torque reduction). The continuous
adaptation methodology provides traction control robustness to vehicles
equipped with a spare tire, or a different final drive such as in the use
of aftermarket parts. The method includes a dual rate adaptation that
allows both fast adaptation and fine tuning capabilities of the ratio.
The method includes comparing the instant driven wheel speed to reference
wheel speed ratio to the filtered driven wheel speed to reference wheel
speed ratio, to obtain a ratio difference. When the difference is above a
threshold, the first filter constant is selected and the first constant
is applied to an adaptation filter, resulting in a first filtered and
adapted ratio. The traction control system is controlled with the adapted
ratio. When the difference is below the threshold, the second filter
constant is selected and the selected constant is applied to the
adaptation filter, resulting in the second filtered and adapted ratio.
The traction control system is controlled with the adapted ratio.