Hybrid powertrain system using free piston linear alternator engines

Hybrid powertrain system, comprising:

• an electrical energy storage device;
• a plurality of electrically-powered torque machines configured to generate and react mechanical torque;
• a plurality of reciprocating free-piston internal combustion engines each including a linear alternator device configured to generate electric power, each reciprocating free-piston internal combustion engine configured to generate a rated output power differing from rated output powers of the other reciprocating free-piston internal combustion engines when operating at resonant speeds;
• a power electronics circuit configured to transfer electric power between each of the linear alternator devices, the electrical energy storage device and the torque machines;
• and
• a control module configured to
• determine mechanical and electrical power demands responsive to an operator torque request and a state of charge of the electrical energy storage device,
• command operation of the torque machines to generate torque responsive to the mechanical power demands, and
• command operations of the reciprocating free-piston internal combustion engines to generate electric power responsive to the electrical power demands.

Hybrid powertrain system, comprising:

• an electrical energy storage device;
• an electrically-powered torque machine configured to generate torque transferable to a driveline and react torque from the driveline;
• a plurality of reciprocating free-piston internal combustion engines each including a linear alternator device configured to generate electric power, each reciprocating free-piston internal combustion engine configured to generate a rated output power differing from rated output powers of the other reciprocating free-piston internal combustion engines when operating at resonant speeds;
• a power electronics circuit configured to transfer electric power between each of the linear alternator devices, the electrical energy storage device and the torque machine;
• and
• a control module configured to
• determine electrical power demands responsive to an operator torque request and a state of charge of the electrical energy storage device, and
• command operations of the reciprocating free-piston internal combustion engines to generate electric power responsive to the electrical power demands.