Method for controlling a hybrid drivetrain and battery device in the hybrid drivetrain

A circuit for controlling a hybrid drivetrain and a pair of batteries in the hybrid drivetrain of a motor vehicle, comprising:

• an alternating current electric machine arranged to drive said hybrid drivetrain at least some of the time;
• a first battery arranged to provide direct current electrical power;
• a second battery arranged to provide direct current electrical power;
• a first pair of complementary transistor switches arranged in parallel and arranged to complete a first direct current circuit to charge said first battery or to complete a second direct current circuit to discharge said first battery;
• a second pair of complementary transistor switches arranged in parallel and arranged to complete a third direct current circuit to charge said second battery or to complete a fourth direct current circuit to discharge said second battery;
• an inverter arranged to convert direct current electrical energy from said first and second batteries into alternating current electrical energy, arranged to supply said alternating current electrical energy to said electric machine, and also arranged to transmit modulations responsive to residual vibrations from a torsional vibration damper within said drivetrain to one of said first, second, third, or fourth direct current circuits via one of said switches;
• and,
• a control unit operatively arranged to control said first and second pair of switches.