Controlled engagement of supercharger drive clutch

The present invention provides a control system and method of controlling a supercharger having an input and a pair of rotors. The method comprises providing a magnetic particle clutch having an input member; an output member and a source of magnetic flux. In the presence of a magnetic field, a magnetically reactive medium disposed between the input and output members is transformed into a torque transmitting coupling that causes the clutch to transition from a disengaged state to an engaged state. The method includes sensing a vehicle parameter and generating a signal operable to engage the clutch in response to the sensed vehicle parameter, so that the transition to the engaged state may be controlled as a function of the sensed vehicle parameter.