Permanent magnet synchronous motor starting method for mileage increasing system provided with hall position sensor

The invention discloses a permanent magnet synchronous motor starting method for a mileage increasing system provided with a hall position sensor, which belongs to the field of motor control. Due to three ways of digital signals outputted by a three-way switch hall sensor through filtering, six accurate rotor position signals can be determined, 360-DEG electric angle space is uniformly divided into six hall intervals, the maximum value of an average electromagnetic torque is solved through a trigonometric function extremum seeking method, a corresponding optimal angle phi in each hall interval is acquired, the corresponding optimal angle phi serves as an angle signal modulated by a space vector to be inputted, the output PWM signal modulated by the space vector controls a three-phase inverter bridge to generate a stator current vector IS, an electromagnetic torque is generated in a stator winding of the permanent magnet synchronous motor, the permanent magnet synchronous motor is dragged to start, an in