Precision electric spindleIt is the "heart" component of high-speed CNC machining machines. Due to the fact that high-speed machining can not only greatly improve the efficiency of processing, but also significantly improve the quality of workpiece processing, it has been widely used, especially in manufacturing industries such as aerospace, automotive, and mold manufacturing.

There are three main control methods for precision electric spindles:

1. The common frequency conversion is scalar drive and control, with constant torque drive as the driving control characteristic, and the output power is proportional to the speed. The dynamic performance of ordinary variable frequency control is not ideal, with poor control performance at low speeds, unstable output power, and no C-axis function. But due to its low price and simple structure, it is generally used in grinding machines and ordinary high-speed milling machines.

2. Vector control technology imitates the control of DC motors, using rotor magnetic field orientation and vector transformation methods to achieve drive and control, with good dynamic performance. The vector control driver has a large torque value in the early stage of startup, coupled with the simple structure and low inertia of the precision electric spindle itself, so the startup acceleration is large, and the allowable limit speed can be reached instantly after startup. This type of driver has two types: open-loop and closed-loop. The latter can provide feedback on position and speed, not only with better dynamic performance, but also with C-axis functionality; The former has poor dynamic performance and does not have C-axis function, but it is cheaper in price.

3. Direct torque control is a new high-performance AC speed regulation technology developed after vector control technology. Its control idea is novel, the system structure is simple and clear, and it is more suitable for driving high-speed electric spindles. It can better meet the dynamic and static characteristics of high-speed electric spindles, such as high speed, wide speed range, and high-speed instantaneous stop. It has become a popular technology in the field of AC transmission.