Hub motor driving system position sensor fault diagnosis and fault-tolerant control method

The invention discloses a fault diagnosis and fault-tolerant control method for a position sensor of a hub motor driving system. The method comprises the following steps: step 1, constructing a nonlinear observer; step 2, inputting the estimated value of the angle of the rotor into a phase-locked loop to obtain a corrected estimated value of the speed of the motor rotor, and then obtaining an estimated value of the position of the motor rotor through integration; step 3, position sensor fault diagnosis; and step 4, carrying out fault-tolerant control on the fault of the position sensor. The method has good dynamic and steady state performance and high parameter robustness, meanwhile, fault diagnosis and fault-tolerant control of the position sensor in the full-speed domain range are achieved through the estimated value obtained by the position observer, the scheme is simple and reliable, the engineering practicability is high, the reliability of obtaining the rotor position angle of the permanent magnet synch