The performance of AC servo motor is better, because AC servo is controlled by sine wave, and the torque ripple is small; The brushless DC servo is controlled by trapezoidal wave. But brushless DC servo control is relatively simple and cheap.
The rapid development of permanent magnet AC servo drive technology makes the DC servo system face the crisis of being eliminated [/p] [p=30,2, left] Since the 1980s, with the development of integrated circuit, power electronics technology and AC variable speed drive technology, the permanent magnet AC servo drive technology has made outstanding development, and the famous electrical manufacturers in various countries have continuously introduced new AC servo motor and servo drive series products. AC servo system has become the main development direction of contemporary high-performance servo system, making the DC servo system face the crisis of being eliminated.
Compared with DC servo motor, permanent magnet AC servo motor has the following advantages:
1.Without electric brush and commutator, the operation is more reliable and maintenance-free.
2.The heating of stator winding is greatly reduced.
3. Small inertia and good system response.
4. High speed and high torque work well.
5. Small size and light weight under the same power.
Source: Network
