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The aim of this paper was the development of a positional system model for a vector control of a static loads’ stand using the electrical drive and the study of the effect of various types of speed controllers and their settings on the dynamics of the transient processes during the simulation of the regulation and disturbance actions. This goal was achieved by the development of a vector control system model using the stand electric drive with the PID-speed controller setting, which ensured minimal speed errors and restrictions in the dynamic loads during the regulating and disturbing action. The synthesis of the current control circuits of the stator and speed in the torque control channel was performed. It was shown that using the existing PI-regulators of speed and current and their settings, the speed dynamic error was found to be as high as 21% at a regulating action, whereas during the disturbing action it was 8%. The achievement of the above indicators of the regulation quality was possible in the presence of the intensity setter at the speed regulator input. In this case the dynamic speed error while operating under control increased substantially. The introduction of the speed PID controller made it possible to reduce dynamic errors, however, it gave no desired results with the standard configuration. Changing the controller’s proportional part parameters allowed us to minimize the dynamic speed error while operation, both under regulating or disturbing influences.

The work is related to investigation of the possibility of increasing the energy efficiency of the heat-exchange network of a vacuum distillation unit at a delayed coking facility, as well as an applying the economic effect evaluation practices of the implemented integration measures for the enterprise modernization. The purpose of the work is to increase a thermal energy recovery of a chemical-technological system and to reduce a percentage of external heat carriers in the overall energy consumption structure of the refinery. The task is achieved by applying design algorithms of a pinch analysis. The most important result of the work is the proven possibility of reducing the external heat carriers’ energy by 1.87 MW and increasing the thermal energy recovery inside the system to 11.26 MW. The significance of the obtained results lies in the fact that the final integrational schemas of heat exchange networks can be used for the actual modernization of the observed manufacture, as well as the considered principles can be adapted by engineers of any other processing industry for the sake of production facilities improvement. The tools of composite curves and grid diagrams are used to determine the energy saving potential of the observed system. The cost curves tools carry out the search of an optimal minimum temperature difference value. Final results are provided in the form of a grid diagram of an integrated heat-exchange system. According to the economic assessment of the implementation effectiveness for developed modernization project, the payback period will not exceed three years.

The work deals with the development of a control system for heat exchangers with variable surface area of heat transfer, used, in particular, for heat pumps intended primarily for heat supply systems using the high-quality law of regulation of the heat supply mode (with a constant flow rate of the heat carrier). The aim of the work is to develop a scheme for the control of a heat exchanger with a variable surface area of heat exchange in which main disturbances will be compensated: i.e. the temperature of the heat carrier, heat carrier’s flowrates, and changes in the thermophysical parameters of the heat carriers. This goal has been achieved using a custom PID controller in the contour of control of the drive of the moving heat-insulating insert. To solve this problem, we obtained the equations of the statics of the heat exchanger with regard to the adjustable insert, the dynamic model of the heat exchanger taking into account this insert. The novelty of the work is control laws of an adjustable heat-conducting insert between the primary and secondary coolants of the heat exchanger, which allow compensating the main disturbances, which influence the heat exchanger. A method has been developed for solving differential-integral equations of heat exchanger statics with an insert (HEI), which allowed analytically expressing the ratio of average integral heat carrier temperatures in a heat exchanger depending on the heat exchanger length, which allows building a control system for a heat exchanger with a variable heat exchange surface area.

The prospects of using the specifics of food raw materials structure for organizing mass transfer in the processes of extraction and dehydration has been shown. Authors studied in depth, in comparison with existing studies, selective effect of microwave energy on moisture in food raw materials. It has been shown that targeted energy supply to nanoscale elements in food raw materials is the basis for the creation of innovative technologies. The instrument for controlling such processes canbe an electromagnetic field. A successful combination of the structure of food raw materials and field parameters can initiate a powerful flow of target components from product volume. Authors have analyzed driving forces of the effect of "barodiffusion".Mechanisms and stages of the processes of components transfer from plant raw materials were proposed for the gradientless supply of electromagnetic energy.The technique, stand and results of visualization of the effect of "barodiffusion" were presented. Created stand includes an electromagnetic energy generator equipped with a digitized endoscopic camera shielded from the field, which allowed the authors to get a visualization of the phenomenon for the first time.The results of experimental studies of extraction and evaporation processes in the microwave field during the processing of food systems of different structure were considered: alcohol-water-containing, dispersed and homogeneous. Obtained results testify to the prospects of introduction of equipment using the effect of "barodiffusion" in the technology of cognac spirits, oils, polyextracts, essences, food concentrates, phytopreparations.