Can the speed and torque of three-phase asynchronous AC motor be controlled at the same time?
Frequency converter frequency control principle is to change the pressure to change the power, frequencyFor example, the reference frequency is 50HZ, and the voltage is proportional to the frequency below 50HZ. The frequency is actually the speed of the reflected image. This torque is constant, which we call constant torque speed regulation. Torque magnitude equalT=9550*P (rated power) /N (rated speed)
Speed control can be said to be the speed closed-loop control is adopted to realize the accurate control of the speed sensor, we control the general frequency can be realized by changing the motor speed and torque control, as is the direct torque control of ----DTC control mode, in general, the precision of the DTC control is more accurate than the speed control, torque control the model is equivalent to realize individual control variables, the inverter motor control direction.
More than 50HZ constant voltage, constant power, but the speed increases at the expense of torque, the above formula N becomes the working speed of the motor, such as 5.5KW 4P-50HZ, at 1000 rpm, torque = 9550 * 5.5/1500=35N.M at 2000 rpm. Torque = 9550 * 5.5/2000=26.2N.M
