Vector control Double Drum Hoist Winch variable frequency speed regulation is: the asynchronous motor in the three-phase coordinate system of the stator AC current Ia, Ib, Ic, through three-phase - two-phase transformation, equivalent to two-phase stationary coordinate system The alternating current Ia1Ib1 is equivalent to the direct current Im1, It1 in the synchronous rotating coordinate system by the rotational transformation of the rotor magnetic field (Im1 is equivalent to the exciting current of the direct current motor; It1 is equivalent to the armature current proportional to the torque) Then, imitating the control method of the DC motor, the control amount of the DC motor is obtained, and the control of the asynchronous motor is realized through the inverse transformation of the corresponding coordinates.
The vector control of the Double Drum Hoist Winch method is epoch-making. However, in practical applications, because the rotor flux linkage is difficult to accurately observe, the system characteristics are greatly affected by the motor parameters, and the vector rotation transformation used in the equivalent DC motor control process is complicated, making the actual control effect difficult to achieve the ideal analysis. result.
