3721 has a very mature speed control technology, due to its unique advantages in speed control, it is widely used in many areas of speed control, frequency control controller is a typical application. The two design schemes mentioned in the paper are representative: the isolation scheme is more mature and has more applications, but the hardware cost is relatively high; the common ground scheme based on a single power supply IPM module is much more attractive, and under the premise of meeting the performance, it can minimize the hardware cost, which greatly improves the market competitiveness of the product.

3721 Overall flip for scrubbing and changing rollers, and adjustable tilt. The lower plaque can move up and down on the guide rail driven by worm gear elevator, and there is one inlet and one outlet respectively. The opening degree of the inlet and outlet is adjusted, that is to say, the size of the roller gap of the lower straightening roller relative to the upper straightening roller is adjusted, so as to change the degree of bending of the copper strip, and the adjustment amount is completed by the servo positioning. The lower roller is also installed in the deed-shaped adjustment block, the local plate shape of the micro-adjustment, through the displacement sensor feedback its actual adjustment position.

The 3721 uses a positioning module to control the AC servo drive for precise positioning of the AC servo motors, and the MPS022 13100203 module collects the feedback signals from the displacement sensors to control the amount of fit adjustment. The three fit adjustments are driven by three AC motors, and an AC inverter is used to control the rotation speed of these three motors at the same time.