Parametric control of efficiency of asynchronous drive by means of converter with the increased power factor

Abstract
Purpose. Development of circuit solution and substantiation of parameters of control system and power part of power supply converter, provided its operation with high power factor and smooth or stepwise methods of energy efficiency control of asynchronous drive.Methodology. The provisions of the theory of electric machines, methods of circuit design of automatic systems in the Multisim component of the National Instruments electronic laboratory, mathematical modeling in the Matlab package were used for research. Findings. Digital models of pulse-phase control systems for stepwise and smooth regulation of the supply voltage of motors using the method of pulse-width modulation of the mains voltage have been developed and built, recommendations are given for the level of load sagging, at which it is necessary to reduce the supply voltage and its magnitude with relay control,  and also tested a smooth control system with coordinate-phase duty cycle control to achieve rational energy efficiency of the drive. Originality. The choice of the switching limit of the relay regulator and the level of rational value of the converter output voltage is substantiated, at which rational and energy-efficient control of the drive is achieved, the algorithm  for determining the RC filtering circuit parameters is proposed to ensure simultaneously the best conditions for switching the converter power switches and the implementation of continuous compensation of the engine reactive power, provided that the converter is operated with an increased power factor.Practical valueThe introduction of a simplified conversion system with a high power factor will create an automatic asynchronous drive system, through which it is possible to achieve energy conservation at the engine, converter and power system, with minimal capital investment in its production.