Fuzzy logic based traction control for electric vehicles

A method of controlling traction of an electric vehicle, comprising:

• detecting, by a traction control system comprising one or more processors and memory, a wheel slip ratio for each wheel of a plurality of wheels of the electric vehicle;
• receiving, by the traction control system from a vehicle control unit of the electric vehicle, an input torque command;
• identifying, by the traction control system, a state of the electric vehicle and a condition of a road in contact with one or more of the plurality of wheels of the electric vehicle;
• determining, by the traction control system, a slip error for each wheel of the plurality of wheels based on the wheel slip ratio for each wheel of the plurality of wheels and a target wheel slip ratio for each wheel of the plurality of wheels;
• inputting, by the traction control system, the state of the electric vehicle and the condition of the road into a fuzzy-logic based control selection technique to select a traction control technique comprising one of a least-quadratic-regulator, a sliding mode controller, a loop-shaping based controller, or a model predictive controller;
• generating, by the traction control system, based on the traction control technique selected via the fuzzy-logic based control selection technique and the slip error for each wheel of the plurality of wheels, a compensation torque value for each wheel of the plurality of wheels;
• transmitting, by the traction control system, one or more commands corresponding to the compensation torque value for each wheel of the plurality of wheels to one or more drive units of the plurality of wheels of the electric vehicle to control traction for the electric vehicle;
• and
• regulating vertical moment of the electric vehicle based on a difference of individual motor torque caused by the compensation torque value for each wheel of the plurality of wheels.

An electric vehicle, comprising:

• a traction control system comprising one or more processors and memory to:
• detect a wheel slip ratio for each wheel of a plurality of wheels of the electric vehicle;
• receive, from a vehicle control unit of the electric vehicle, an input torque command;
• determine a slip error for each wheel of the plurality of wheels based on the wheel slip ratio for each wheel of the plurality of wheels and a target wheel slip ratio for each wheel of the plurality of wheels;
• identify a state of the electric vehicle and a condition of a road in contact with one or more of the plurality of wheels of the electric vehicle;
• input the state of the electric vehicle and the condition of the road into a fuzzy-logic based control selection technique to select a traction control technique comprising one of a least-quadratic-regulator, a sliding mode controller, a loop-shaping based controller, or a model predictive controller;
• generate, based on the traction control technique selected via the fuzzy-logic based control selection technique and the slip error for each wheel of the plurality of wheels, a compensation torque value for each wheel of the plurality of wheels;
• transmit one or more commands corresponding to the compensation torque value for each wheel of the plurality of wheels to one or more drive units of the plurality of wheels of the electric vehicle to control traction for the electric vehicle;
• and
• regulate vertical moment of the electric vehicle based on a difference of individual motor torque caused by the compensation torque value for each wheel of the plurality of wheels.