Method for detecting and controlling wheel slip of an electrical trailer braking system

A trailer brake control system for a vehicle, comprising:

• a vehicle acceleration sensor outputting a vehicle acceleration signal;
• a vehicle velocity sensor outputting a vehicle velocity signal;
• a vehicle brake system outputting a vehicle brake signal;
• a trailer brake control output connection;
• and
• a controller including a memory storing a combined vehicle and trailer mass, the controller:
• receiving the vehicle brake signal, the vehicle acceleration signal, and the vehicle velocity signal;
• responsive to the vehicle brake signal indicating application of the vehicle brake system, outputting a trailer brake signal via the trailer brake control output connection;
• determining an effective combined brake torque by multiplying the combined vehicle and trailer mass by the vehicle acceleration signal and by a braked tire radius;
• determining a commanded combined brake torque as a sum of a commanded vehicle brake torque, derived from the vehicle brake signal, and an estimated trailer brake torque, determined from the trailer brake signal;
• detecting a trailer wheel slip condition responsive to the commanded combined brake torque varying from the effective combined brake torque by a predetermined amount;
• and
• responsive to detecting the trailer wheel slip condition, adjusting the trailer brake signal to reduce a trailer brake torque command.

A method for mitigating wheel slip in a braked trailer wheel, comprising:

• receiving vehicle brake signal from a vehicle brake system, a vehicle acceleration signal from a vehicle acceleration sensor, and a vehicle velocity signal from a vehicle velocity sensor;
• responsive to the vehicle brake signal indicating application of the vehicle brake system, outputting a trailer brake signal via a trailer brake control output connection;
• determining an effective combined brake torque by multiplying a combined vehicle and trailer mass by the vehicle acceleration signal and by a braked tire radius;
• determining an effective trailer brake torque by subtracting a commanded vehicle brake torque, derived from the vehicle brake signal, from the effective combined brake torque;
• detecting a trailer wheel slip condition responsive to the effective trailer brake torque being less than an estimated trailer brake torque, determined from the trailer brake signal;
• and
• responsive to detecting the trailer wheel slip condition, adjusting the trailer brake signal.