TRANSIENT MODELING IN COMMON DC LINK OF POWER CONVERTERS

Subject of Research. The paper presents a mathematical model of an electric drive convertor operating in a common DC link for the 280-kW power level of the BELAZ-90 mining truck. The model is developed in MATLAB Simulink. The novelty of the proposed model is as follows: it implements the main circuit new topology for research of two converter drives operation connected to the common capacitor of the DC link. The model provides the possibility of studying transients in a distributed DC link with the aim of reducing current ripples both in the capacitor bank of inverters and in the common DC link. Method. We proposed the hardware method with a view to reduce ripples. It introduces the additional inductance installed between capacitors in the DC link and, with pulse-width modulation at the algorithmic level, a phase shift of the reference signals of two parallel inverters. Mathematical model was developed for estimation of current ripples between inverter and DC link capacitor and between the capacitor and power supply. Main Results. It is shown that the proposed software method decreases twice the current ripples between inverter and DC link capacitor, and the current between invertor capacitor and the power supply is reduced up to one-tenths of its previous value. Practical Relevance. This research can be practically used for control of the current load of power converter elements when developing the multi-motor electric drives in machine tool applications and hybrid electric powertrains.