Variable speed hybrid electric supercharger assembly and method of control of vehicle having same

A supercharger assembly for an engine having a crankshaft and an air intake manifold defining a plenum through which air flow is provided to the engine, the supercharger assembly comprising:

• a supercharger upstream of the plenum in the air flow to the engine, wherein the
• supercharger has a first rotor mounted on and rotatable with a first shaft and a
• second rotor meshing with the first rotor and mounted on and rotatable with a
• second shaft via rotation of the first shaft;
• an electric motor-generator selectively operable as a motor and as a generator;
• a planetary gearing arrangement having a first member operatively connected to be
• rotated by the electric motor-generator, a second member connectable to be
• rotated by the engine crankshaft, and a third member operatively connected for
• rotation with the first shaft;
• a housing assembly having:
• a rotor housing portion configured to radially surround the first and second rotors;
• and
• an inlet cover portion configured to attach to the rotor housing portion such that the first shaft extends from within the rotor housing portion into the inlet cover portion and is supported by the inlet cover portion;
• wherein the inlet cover portion at least partially defines an air inlet passage through which air is provided to the rotors;
• and wherein the inlet cover portion further defines a cavity and supports the brake within the cavity;
• two selectively engageable torque-transmitting mechanisms including a clutch selectively engageable to operatively connect the second member for rotation with the engine crankshaft, and a brake selectively engageable to hold the first shaft stationary;
• and
• a control system configured to control the electric motor-generator, the brake and the clutch to achieve different operating modes.

A supercharger assembly for an engine defining a plenum through which air flows to the engine;

• the supercharger assembly comprising:
• a supercharger in series with the plenum in the air flow to the engine, wherein the supercharger has a first rotor mounted on and rotatable with a first shaft and a second rotor meshing with the first rotor and mounted on and rotatable with a second shaft via rotation of the first shaft;
• a bypass passage operatively connecting an air inlet to a throttle body;
• a bypass valve positioned in the bypass passage to selectively permit air flow through the bypass passage between the air inlet and the throttle body and bypassing the first and second rotors;
• an electric motor-generator selectively alternately operable as a motor and as a generator;
• an energy storage device operatively connected to the electric motor-generator for supplying electric power to the electric motor-generator when the electric motor-generator functions as a motor and for receiving electric power from the electric motor-generator when the electric motor-generator functions as the generator;
• a planetary gearing arrangement having a first member operatively connected to be rotated by the electric motor-generator, a second member, and a third member operatively connected for rotation with the first shaft;
• a pulley configured to be operatively connectable to a crankshaft and having a pulley shaft connected for rotation with the second member;
• a gear train having a first gear member connected for rotation with the electric motor-generator and a second gear member connected for rotation with the third member of the planetary gearing arrangement, the gear train thereby transferring torque between the planetary gearing arrangement and the electric motor-generator;
• two selectively engageable torque-transmitting mechanisms including an electromagnetic clutch selectively engageable to operatively connect the second member for rotation with the engine crankshaft, and an electromagnetic brake selectively engageable to hold the first shaft stationary;
• and
• a control system configured to control the electric motor-generator, the bypass valve, the brake and the clutch to achieve different operating modes.

A supercharger assembly for an engine having a crankshaft, a throttle body, an air intake manifold defining a plenum downstream of the throttle body, and a selectively positionable throttle valve in the throttle body controlling air flow to the engine;

• the supercharger assembly comprising:
• a Roots-type supercharger in series with the throttle valve upstream of the throttle body in the air flow to the engine;
• wherein the supercharger has a first rotor mounted on and rotatable with a first shaft and a second rotor meshing with the first rotor and mounted on and rotatable with a second shaft via rotation of the first shaft;
• a housing assembly defining an air inlet to the supercharger;
• a bypass passage operatively connecting the air inlet to the throttle body;
• a bypass valve positioned in the bypass passage to selectively permit air flow through the bypass passage between the air inlet and the throttle body and bypassing the first and second rotors;
• an electric motor-generator selectively alternately operable as a motor and as a generator;
• an energy storage device operatively connected to the electric motor-generator for supplying electric power to the electric motor-generator when the electric motor-generator functions as a motor and for receiving electric power from the electric motor-generator when the electric motor-generator functions as the generator;
• a planetary gearing arrangement having a first member connected to be rotated by the electric motor-generator, a second member connectable to be rotated by the engine crankshaft, and a third member connected for rotation with the first shaft;
• two selectively engageable torque-transmitting mechanisms consisting of a clutch selectively engageable to operatively connect the second member for rotation with the engine crankshaft, and a brake selectively engageable to hold the first shaft stationary;
• and
• a control system configured to control the electric motor-generator, the throttle valve, the bypass valve, the brake and the clutch to achieve an operating mode in which the electric motor-generator starts the engine, an operating mode in which the engine is on and the electric motor-generator varies a speed of the rotors via the planetary gearing arrangement to control air pressure in the plenum, and an operating mode in which air flows to the engine bypasses the rotors through the bypass passage.