3 results about "Switching table" patented technology

This invention belongs to the technical field of workbench structure, specifically providing a drive structure for an exchangeable workbench. It includes a base with an internal drive cavity, a drive shaft rotatably mounted within the drive cavity, and several needle rollers arranged in a circumferential array fixedly connected to the drive shaft. A camshaft, capable of sliding up and down and rotating, is located within the drive cavity. A camshaft guide rail, cooperating with the needle rollers, is provided on the camshaft. The camshaft guide rail includes a lifting section, a rotating section, and a lowering section connected sequentially from end to end. The bottom of the drive shaft extends through the drive cavity and is fixedly connected to the output end of a drive device. The bottom of the camshaft extends through the drive cavity and into a damping buffer cavity. A buffer spring is fixedly connected to the bottom of the damping buffer cavity. A chuck at the top of the buffer spring is rotatably connected to a connecting plate at the bottom of the camshaft. A camshaft limiting assembly is also provided within the damping buffer cavity. The top of the camshaft extends through the base and is fixedly connected to the workbench. This structure is compact, reliable in operation, and has built-in buffer protection, enabling smooth movement of the workbench.

The application provides a field weakening method of a permanent magnet synchronous motor based on sector offset, and belongs to the technical field of motor control. The field weakening method is suitable for a field weakening method using a control algorithm of a switching table, and achieves the effect of field weakening by changing d-q axis voltage distribution. The field weakening method comprises the following steps: S1, observing a load via a load torque observer; S2, substituting a required maximum motor speed and the observed load into a formula to calculate a sector offset; S3, inputting the calculated sector offset into a switching table to perform sector offset; and S4, inputting an electromagnetic torque signal into the switching table, outputting a switching signal via the offset sector, and further controlling the motor. The application provides a field weakening method of a permanent magnet synchronous motor based on sector offset, the d-q axis voltage distribution is changed by rotating the sector clockwise, the offset can be calculated according to the maximum motor speed, an analytical solution is obtained, the method is suitable for algorithms such as flux linkage closed loop direct torque control, and the field weakening effect is excellent in the whole speed range.