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Power supply and electrical equipment
Autotransformer-rectifier units in aircraft electric power supply systems. Three-phase interphase transformer. Part 2
Konyakhin С., Konyakhin V.The operation of interphase transformer in ATRU with eighteen-pulse rectification is described. Main calculating formulas and KVA-ratings considered IPT for ATRUs with regular and irregular nine-phase voltages systems are determined.
Keywords: ATRU, regular and irregular nine-phase voltages systems, eighteen-pulse rectification, interphase transformer, KVA-ratings.The effect of Sommerfeldand wagon dynamics
Chernysheva J., Gorskiy A., Sereda A.The article describes vertical oscillations of freight train wagons. The analytical formulas help to deter-mine wagons speed. It is special resonance speed. The resonance appears between self-oscillations and oscillations of rail roughness. It is shown, that significant rise of oscillations wagons amplitude re-sult to picking of locomotive power, at that time speed decreases. This manifestation is important at that time of transition to high speed.
Keywords: induction motor, freight train, wheel tramp, oscillation, resonant frequency, speed, line.Generalized presence of phase voltage of a multiphase transmitter
Tereshkin V.In the generalized form, the phase voltage of the multiphase converter is represented as a function of the input voltage and the number of phases of the converter. In the analytical form, the relationships connecting the instantaneous values of the phase voltage with the number of phases of a multiphase converter are presented. It is established that under certain control algorithms for a multiphase converter, regardless of the number of phases, the amplitude of the first harmonic of the phase voltage remains unchanged and at a single input voltage is 0,637.
Keywords: multiphase converter, control algorithms for a multiphase converter, phase voltage form, amplitude of the first harmonic of phase voltage.