Software Tool for Auto-Tuning of the Electric Drive Control System for Metal-Cutting Machines

The paper deals with development of a software tool for auto-tuning the electric drive control system for metal cutting machines (MCM). The analysis of software of the world leading manufacturers of computer numerical control (CNC) systems allowed us to formulate the requirements to the auto-tuning tool. Using a typical structure of a two-loop MCM control system built on the principles of subordinate control as an example, a universal algorithm of auto-tuning is considered, for operation of which it is required to set only the desired performance (bandwidth) and phase stability margin. For this algorithm a developed modification is presented, which allows one to obtain several variants of controller gains depending on the desired “stiffness” of the loop performance with only the maximum controller bandwidth as a setting parameter. The interface of the tool is presented, as well as the results of its work in the form of the Bode diagrams of the tuned loops on the real metal cutting machine and the roundness diagram for the said machine.