The invention discloses a compound steering-by-wire
system driven by a passenger car motor and a
steering control method. In the
system, a road sense motor is connected with a road sense motor deceleration mechanism and connected with a steering
drive shaft provided with a torque angle sensor, a
steering wheel is successively connected with the steering
drive shaft, a torque rod, an upper transmission shaft and an
electromagnetic clutch, in the steering executive motor deceleration mechanism, a first worm gear is installed on a steering gear shaft connected with a lower transmission shaft, andthe two ends of a first worm are both connected with a steering executive motor; and a steering
pinion in a steering gear is coaxially and fixedly connected with the first worm gear, the two ends ofa rack are connected with steering wheels correspondingly, an ECU is connected with the torque angle sensor, the road sense motor, the
electromagnetic clutch and the steering executive motor through signals. The method includes a conventional
steering control method, a failure
backup steering control method and a mechanical steering control method. According to the compound steering-by-wire systemdriven by the passenger car motor and the steering control method, in the case of the failure of electrical elements of the
system, the steering action can be successfully completed, and the safety of the
steering system is greatly improved.