Patent ID: 8109855
Filing Date: 2012-02-07
Classification: B60K,B60L,B60W,Y02T,Y10T

Abstract:
1. Method for controlling the coupling and the decoupling of the first motor and the second motor of a parallel hybrid drive train of the type comprising a first motor that drives a main input shaft of a gearbox, a second motor, and a coupling/decoupling means for the second motor and the first motor, maneuverable between an open position and a closed position to make it possible to change the gearbox ratio when the drive train is operating in hybrid mode, according to which the drive train is controlled so as to decouple the second motor and the first motor, then to change the gearbox ratio, and to recouple the second motor and the first motor, wherein control laws are used for the drive unit such that during coupling and during decoupling, the torque setpoint for the main shaft has a discontinuity selected so as to offset the difference between the inertia carried by the main shaft when the second motor is coupled to the first motor and the inertia carried by the main shaft when the second motor is decoupled from the first motor in order to avoid any sudden variation in acceleration of the main shaft driven by the drive unit at the moment of decoupling or coupling, and wherein a reference torque setpoint is defined for the drive unit, to be sent to the main shaft when the two motors are coupled, as well as a reference torque setpoint to be sent to the main shaft when the two motors are decoupled; based on the resisting torque to which the main shaft is subjected and the inertias it must carry when the motors are coupled and decoupled, a natural deceleration torque is defined for the drive unit when the motors are coupled, as well as a natural deceleration torque when the motors are decoupled; a first transition law is defined to govern the transition, for coupling, from the reference torque to transmit to the main shaft when the motors are coupled to the natural deceleration torque when the motors are coupled, and the reverse for decoupling; a second law is defined to govern the transition, for coupling, from the reference torque to transmit to the main shaft when the motors are decoupled to the natural deceleration torque when the motors are decoupled, and the reverse for decoupling; and during coupling or decoupling, the drive unit is controlled so as to transmit to the main shaft a torque consistent with the transition law that corresponds to the initial operating mode of the drive unit, up to the moment when the operating mode of the drive unit changes, and then the drive unit is controlled so as to transmit to the main shaft a torque consistent with the transition law that corresponds to the target operating mode of the drive unit.