说明：  The induction motor is fed by a current-controlled PWM inverter which is built using a Universal Bridge block. The motor drives a mechanical load characterized by inertia J, friction coeficient B, and load torque TL . The speed control loop uses a proportional-integral controller to produce the quadrature-axis current reference iq* which controls the motor torque. The motor flux is controlled by the direct-axis current reference id*. Block DQ-ABC is used to convert id* and iq* into current references ia*, ib*, and ic* for the current regulator. Current and Voltage Measurement blocks provide signals for visualization purpose. Motor current, speed, and torque signals are available at the output of the Asynchronous Machine block.