TRACTION CONTROL DEVICE AND TRACTION CONTROL METHOD

摘要

A parameter calculation part calculates an adaptive gain coefficient ‘k’ for the road surface conditions, based on frictional coefficient μ and a slip ratio λ from an acquisition part and a coefficient ‘b’ in a storage part. Subsequently, the parameter calculation part calculates an adaptive time constant τ by which the stability of traction control can be ensured, based on the gain coefficient ‘k’ and a coefficient ‘a’ within the storage part. Along with the calculated gain coefficient ‘k’ being set in a gain multiplication part, the calculated time constant τ is set in a filter part. According to these settings, model following control is executed by taking, as a reference model, an adhesion model in which the driving wheel does not slip. This enhances slip prevention performance while ensuring control stability, making stable travel possible while ensuring the required drive force in accordance with road surface state.

主权项

1. A traction control device that performs traction control for a moving body having a driving wheel which is driven by a motor, comprising:
an acquisition part configured to acquire a torque instruction value for said driving wheel, the rotational speed of said driving wheel, and friction coefficient information for the road surface upon which said driving wheel runs; a torque command value calculation part configured to calculate the torque command value to be outputted to the motor for driving said driving wheel, on the basis of said acquired torque instruction value and a correction amount; an estimated torque value calculation part configured to calculate an estimated value of torque operating upon said driving wheel, on the basis of said calculated torque command value and a model for torque transmission to said driving wheel; an inverse torque value calculation part configured to calculate a torque value corresponding to said acquired rotational speed, according to a reference model in which no slip of said driving wheel takes place; a filter part configured to apply a first-order delay to the difference between the result of calculation by said estimated torque value calculation part and the result of calculation by said inverse torque value calculation part; and a gain multiplication part configured to feed back, to said torque command value calculation part, as said correction amount, the result obtained by multiplying said difference to which said first-order delay has been applied by a gain coefficient; wherein said gain coefficient takes a value which is adaptively set by using said acquired friction coefficient information; and the time constant of said filter part takes a value which is adaptively set by utilizing said acquired friction coefficient information, or a value which is determined on the basis of the estimated value of the maximum value taken by said gain coefficient.