Machinery & Energetics

The modern asynchronous controlled electric drive is based on the use of semiconductor voltage converters of various types, for which, due to complexity or high cost, little attention is paid to the study of various performance characteristics. With the development of computer modeling, it became possible to deepen the research of these processes. The purpose of the study is to improve the quality of the harmonic composition of the output voltage of semiconductor converters of a regulated three-phase asynchronous electric drive. The study of a three-phase semiconductor voltage converter with pulsewidth control was carried out using the provisions of the theory of electrical circuits of sinusoidal and nonsinusoidal periodic current and computer simulation in the MatLab system. The created computer model provides a selection procedure and selected RC snubber parameters for protecting the electronic key and improving the harmonic composition of the output voltage and current of the converter. The results of the research on the computer model of electromagnetic processes in the circle of the power electronic key showed that when the active-inductive load (R = 48 Ohm, L = 0.0197 H) corresponds to the winding data of the AIRP80-A6U2 motor, the voltage pulses reach 60 kV. The selected snubber parameters (RS = 150 Ω, CS = 0.3 μF) enable the switching of the transistor switch to reduce the voltage pulse to 1.1 kV. At the same time, the composition of the higher harmonics is not violated, but their influence as a percentage of the main harmonic is reduced.

electromagnetic processes, higher harmonics, voltage and current curve shape, computer model, adjustable electric drive