Vehicle behavior controller

A vehicle behavior controller comprising:

• a running state detecting unit configured to detect a running state of a vehicle;
• an unstable state judging unit configured to judge an unstable state of the vehicle based on the running state;
• a motor generator connected to a prime mover of the vehicle, the motor generator operating as a power generator for using an output of the prime mover to generate power and an electric motor for assisting the output of the prime mover;
• and
• a control means for controlling an operation of the motor generator based on r.p.m. of the motor generator,
• wherein:
• the unstable state judging unit judges the unstable state when the vehicle is in one of an understeer state and an oversteer state,
• the control means controls the operation of the motor generator so as to generate braking torque based on an externally input torque command value when the unstable state is judged;
• and
• the control unit selects, based on the r.p.m. of the motor generator, whether to control power generation of the motor generator to generate the braking torque or whether to short-circuit an armature winding of the motor generator to generate the braking torque, and
• the r.p.m of the motor generator, when the control unit selects to control power generation of the motor generator, is higher than the r.p.m of the motor generator when the control unit selects to short-circuit an armature winding of the motor generator,
• the motor generator includes more than one upper arm switching elements and more than one lower arm switching elements, the upper arm switching elements being positioned above the lower arm switching elements,
• and the more than one lower arm switching elements are turned ON to short-circuit the armature winding as a result of the control means selecting to short-circuit the armature winding to generate the braking torque.