Method of adapting yaw rate error in controlling limited slip differentials

摘要

The present invention comprises a method of controlling a clutch based limited slip differential (LSD) of a vehicle in a PID-controller (3) based closed loop control system, said control system including a PID-controller (3) for controlling said LSD to control the vehicle's yaw rate, said PID-controller (3) being adapted to create a control signal based on yaw rate error as calculated on basis of reference and measured yaw rates, said control signal being supplied to an actuating means operatively coupled to said LSD for actuating thereon based on said control signal; said system further including a reference yaw rate determination logic (6) for determining a reference yaw rate and an adaptation logic (7) for creating an adapted yaw rate error to be provided to said PID-controller (3), said adaptation logic (7) being interconnected between said reference yaw rate determination logic (6) and said PID-controller (3) and being provided with said reference yaw rate and a measured yaw rate as measured by a yaw rate sensing means; wherein said method comprising a step of adapting said yaw rate error when releasing throttle in making a turn performed by said adaptation logic (7), which adaptation of the yaw rate error comprises the steps of: initiating of adaptation of the yaw rate error; dividing of the measured yaw rate by the reference yaw rate to calculate a yaw rate ratio at initiation of the adaptation; and multiplying said yaw rate ratio with the reference yaw rate during said throttle off condition to create an adapted error rate signal to be supplied to said PID-controller (3).