This paper examines the main requirements for the electric drive systems of a class of boring machines with digital program control. On this basis, a methodology for choice of the spindle drives is offered. The algorithm takes into account the specific features of the technological processes, the treated materials, the tools used and their wear, as well as the mechanical gear types. The experimental studies of the implemented electric drives for the spindle are presented and discussed. The research carried out and the results obtained can be used in the development of such drives for the studied class of machine tools.

An approach to dual-zone speed control of DC motor electric drives is presented in this paper. The new point is that in the syntheses of controllers a combination between setting of closed-loop system poles (modal control) and optimal control through the quadratic quality criterion minimization is applied. Optimal modal control is achieved whereat a new type of complex criterion for selection of the functional is used. This approach allows taking into consideration the controlled object parameters' change at determination of the optimal modal controller coefficients when speed is regulated above the rated value. The research carried out as well as the results obtained can be used in the design, optimization and tuning of such types of drive systems

In this paper are analyzed and formulated the main requirements for the drive systems of a class of modernized boring machines with digital program control. On this basis, a methodology for optimal selection of feed drives is offered. The respective algorithm takes into account the specific features of the technological process, the treated material, the tools used and their wear, the mechanical gears types and the guides. Concrete examples with DC and AC electric drives are presented, illustrating the practical application of the methodology. The research held as well as the results obtained can be used in the development of such electric drives for the studied class of machine tools with digital program control.

In this paper are analyzed and formulated the basic requirements for the drive system of a class of modernized drilling machines. On this basis, a methodology for optimal choice of the feed and spindle drives is offered. The respective algorithm takes into account the specific features of the technological processes, the processed materials, the tools used and their wear, as well as the mechanical gear types. Examples with DC and AC motor drives for the coordinate axes and the spindle are presented, illustrating the practical application of the offered methodology. The research carried out and the results obtained can be used in the development of drive systems for the studied class of machine tools.

An approach to sensorless speed control of permanent magnet DC motor drives is presented in this paper. The motor speed has been estimated indirectly by the respective back EMF voltage. Using a discrete vector-matrix description of the controlled object, an optimal modal state observer has been synthesized, as well as an optimal modal controller. The results obtained show that the applied control method can ensure good performance.