Characteristics of AC Servo MotorWith the development of integrated circuits, power electronics technology and AC variable speed drive technology, permanent magnet AC servo drive technology has developed prominently. Well-known electrical manufacturers in various countries have successively launched their own AC servo motors and servo drive series products, which are continuously improved and updated. . The AC servo system has become the main development direction of contemporary high-performance servo systems, making the original DC servo facing the crisis of being eliminated. The development of AC servo drives in the transmission field is changing with each passing day. So what are the requirements for the characteristics of AC servo motors?
The following will be explained by the technicians of the JACT servo drive manufacturer:
As a servo motor, AC servo motor must not only have good linearity mechanical characteristics and adjustment characteristics, but also servo: when the control signal voltage is strong, the motor speed is high; when the control signal voltage is weak, the motor speed is low; If the control signal voltage is equal to zero, the motor does not rotate.
However, the speed of an ordinary asynchronous motor is not a single-valued function of torque, and it can only operate stably within a certain range. This characteristic is suitable as a motor for driving purposes.
But as a servo motor, the mechanical characteristics must be a single value function and have linear characteristics as much as possible to ensure stable operation in the entire speed range.
To meet this requirement, the usual approach is to increase the rotor resistance so that the slip rate when the maximum torque is generated. Make the servo motor close to linear in the entire speed range.
In general, the greater the rotor resistance, the closer the mechanical characteristics are to linearity, but the smaller the locked-rotor torque and maximum output power, the lower the efficiency. Therefore, the efficiency of AC servo motors is lower than that of motors for general drive purposes.
In short, AC servo motors must have good linearity mechanical characteristics and adjustment characteristics, and must also have servo characteristics.