A method for turning a shaft characterised by comprising: receiving at a first variable frequency motor drive controller a first direct current power input and a first operating signal by torque control and brake pedals; receiving at a second variable frequency motor drive controller a second direct current power input and a second operating signal by the torque control and brake pedals; in response to the first operating signal, producing a first variable frequency alternating current control signal from the first direct current power input using the first variable frequency motor drive controller; in response to the second operating signal, separately producing a second variable frequency alternating current control signal from the second direct current power input using the second variable frequency motor drive controller; applying the first variable alternating current control signal to a first stator for producing a first rotating magnetic field in response to the first variable frequency alternating current control signal; applying the second variable alternating current control signal to a second stator for producing a second rotating magnetic field, in response to the second variable frequency alternating current control signal and synchronized to the first rotating magnetic field; inducing a first induced magnetic field around a conductor in a first inductive rotor, in response to the first rotating magnetic field; inducing a second induced magnetic field around a conductor in a second inductive rotor, in response to the second rotating magnetic field; applying a first rotational force between the first rotating magnetic field and the first induced magnetic field to the shaft; and applying a second rotational force between the second rotating magnetic field and the second induced magnetic field to the shaft; whereby the first and second operating signals are identical so that the first variable frequency motor drive controller and the second variable frequency motor drive controller can act as a synchronous power source. receiving at a first variable frequency motor drive controller a first direct current power input and a first operating signal by torque control and brake pedals; receiving at a second variable frequency motor drive controller a second direct current power input and a second operating signal by the torque control and brake pedals; in response to the first operating signal, producing a first variable frequency alternating current control signal from the first direct current power input using the first variable frequency motor drive controller; in response to the second operating signal, separately producing a second variable frequency alternating current control signal from the second direct current power input using the second variable frequency motor drive controller; applying the first variable alternating current control signal to a first stator for producing a first rotating magnetic field in response to the first variable frequency alternating current control signal; applying the second variable alternating current control signal to a second stator for producing a second rotating magnetic field, in response to the second variable frequency alternating current control signal and synchronized to the first rotating magnetic field; inducing a first induced magnetic field around a conductor in a first inductive rotor, in response to the first rotating magnetic field; inducing a second induced magnetic field around a conductor in a second inductive rotor, in response to the second rotating magnetic field; applying a first rotational force between the first rotating magnetic field and the first induced magnetic field to the shaft; and applying a second rotational force between the second rotating magnetic field and the second induced magnetic field to the shaft; whereby the first and second operating signals are identical so that the first variable frequency motor drive controller and the second variable frequency motor drive controller can act as a synchronous power source.