Adopting ac servo motor as the driving device, can the dc servo motor and a high precision, high performance as the half closed loop or closed loop control system.

采用交流伺服电机作为驱动器件，可以和直流伺服电机一样构成高精度，高性能的半闭环或闭环控制系统。

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A kind of the pulse control mode, the drive and motor closed loop, but not to the numerical control system, the feedback device, in a sense, can open loop control called the servo control.

一种采用脉冲控制方式，此种驱动器与电机闭环，但不反馈到数控系统，这种驱动器在某种程度上可称为开环控制的伺服控制。

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For digitized AC servo system, it needs software to support it's closed-loop control. Its control quality is decided by the program of control computation directly.

数字化的交流伺服系统是靠软件完成控制计算来支持闭环控制的，它的控制计算程序直接决定了系统的控制质量。

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