Apparatus and method for regulating active driveline damping in hybrid vehicle powertrain

A method for regulating an active damping system having at least one torque-generative device operable to selectively attenuate vibrations in a hybrid powertrain having an engine and at least one motor/generator assembly selectively drivingly connectable to a power transmission, the method comprising:

• providing a controller having a processor configured for:
• monitoring a damping torque command sent to the at least one torque-generative device by the active damping system;
• filtering said damping torque command;
• detecting if a switch occurs, said switch including said damping torque command switching from one of greater than or less than said filtered damping torque command to the other of greater than or less than said filtered damping torque command and a magnitude of said switch exceeding a predetermined switch magnitude;
• incrementing a total number of switches if said switch occurs;
• determining if said total number of switches exceeds a switch counter threshold within a preset sample period;
• determining if a current damping torque exceeds a predetermined damping torque threshold if said total number of switches exceeds said switch counter threshold;
• and
• decreasing a damping torque multiplier to zero if said current damping torque exceeds said predetermined damping torque threshold to prevent the damping torque command from being applied to the at least one torque-generative device.

A control apparatus for regulating an active damping system having at least one torque-generative device operable to generate a damping torque configured to attenuate vibrations in a hybrid powertrain having an engine and at least one motor selectively drivingly connectable to a power transmission, the apparatus comprising:

• a controller in operative communication with the at least one torque-generative device and configured to control operation of the same, wherein said controller selectively distributes a damping torque command signal to the least one torque-generative device;
• wherein said controller is programmed and configured to filter said damping torque command signal and determine if said damping torque command signal switches from one of greater than or less than said filtered damping torque command signal to the other of greater than or less than said filtered damping torque command signal and a magnitude of said switch exceeding a predetermined switch magnitude;
• wherein said controller is programmed and configured to increment a total number of switches each time said damping torque command signal switches and determine if said total number of switches exceeds a switch counter threshold within a preset sample period;
• and
• wherein said controller is programmed and configured to determine if a current damping torque exceeds a predetermined damping torque threshold if said total number of switches exceeds said switch counter threshold, and respond by decreasing a damping torque multiplier to zero if said current damping torque exceeds said predetermined damping torque threshold.