Traction Control for a PM Axial-Flux In-Wheel Motor

The traction control is a tool to increase stability and safety of vehicles and it has a greater performance potential in electrical vehicles than in ICV. Moreover, the traction control allows the EV to operate more efficiently preventing slippage in acceleration and permitting the use of high-efficiency low-drag tires. The presented approach can compete with the well-established techniques, but it offers a lighter tuning procedure. This paper presents an approach to the longitudinal control of a single wheel adopting a configuration based on an adherence estimator and a controller of the adherence gradient. The presented approach allows tracking of the value of the adherence derivative in a wide operating range without any knowledge of the road conditions. The work is based mainly on experimental tests. The test rig computes the vehicle dynamics in real-time and loads accordingly the drive under test. The controller was experimentally verified showing good behavior.