In the system scheme, the frequency converter is equipped with a frequency dividing card to make the system work in the closed-loop vector control mode and realize the frequency conversion positioning function. Because the automatic lathe has large load inertia and short deceleration, it needs to be equipped with braking resistance. The specific selection method is "V560 Series High-Performance vector converter manual". Figure 1 electrical wiring diagram principle of spindle frequency conversion positioning system the overall control block diagram of this scheme is shown in Figure 2 below. The inverter takes power from the three-phase power grid by uncontrolled rectification, and the three-phase inverter full bridge controls the spindle motor in real time through space vector modulation (SVPWM) and closed-loop vector control (fieldorientationcontrol); Through the transmission mechanism, the speed signal is fed back to the frequency converter control unit. The fed back speed signal is converted into an angle signal through the frequency divider card, which is different from the set angle. After PID unit operation (acceleration process PID, steady-state process PID), the speed command of the spindle motor control (with torque limiting function) is obtained.
客服1