How the Servo drive works

- Nov 06, 2018-

At present, the mainstream servo drivers use digital signal processor (DSP) as the control core, can realize the more complex control algorithm, to achieve digitalization, networking and intelligence. Power devices generally use intelligent Power Module (IPM) as the core design of the drive circuit, IPM internal integration of the drive circuit, at the same time with Overvoltage, overcurrent, overheating, undervoltage and other fault detection protection circuit, in the main circuit also added soft-start circuit, in order to reduce the impact of the START process on the drive. The Power drive unit first through the three-phase full-bridge rectifier circuit to the input three-phase electricity or municipal power rectifier, to obtain the corresponding direct current. After rectifying a good three-phase electric or municipal power, and then through the three-phase sinusoidal PWM voltage inverter frequency conversion to drive three-phase permanent magnet Synchronous AC servo motor. The whole process of the Power Drive unit can simply be said to be the process of AC-DC-AC.

The main topological circuit of Rectifier Unit (AC-DC) is the three-phase full-bridge non-controlled rectifier circuit.

With the large-scale application of servo system, servo driver use, servo driver debugging, servo drive maintenance are servo drivers in today's more important technical issues, more and more industrial control technology service providers on the servo drive technology in-depth research. Servo driver is an important part of modern motion control, which is widely used in automation equipment such as industrial robot and NC machining center. In particular, the servo driver used to control AC permanent magnet synchronous motor has become a research hotspot at home and abroad. At present, the current, velocity and position 3 closed-loop control algorithm based on vector control is widely used in AC servo drive design.

Whether the speed closed-loop design in this algorithm is reasonable or not plays a key role in the whole servo control system, especially the speed control performance.