Development of a Power Source for Vibroacoustic Diagnosis Position of Locomotive Depot Bearings

Abstract

Purpose: Two possible variants of power sources are considered: controlled three-phase bridge rectifier circuit with a step-down transformer and a pulse converter, getting power from the mains via uncontrolled three-phase bridge rectifier (Larionov circuit) for bringing into rotation with the required frequency of wheel-motor units of electric locomotives and electric trains at the position of indiscriminate diagnosis of bearings. In both cases, it is assumed that power sources receive electro-energy from a depot circuit — 380/220 V, 50 Hz. The comparison of proposed power supply options based on the assessment of energy consumption efficiency is carried out. A capacity coefficient and capacity loss in power supplies are used as measures for energy-consumption efficiency. Methods: Analytical methods are used to determine capacity losses in a transformer, controlled three–phase thyristor rectifier, uncontrolled three-phase diode rectifier, input filter of a pulse converter, IGBT transistor and reverse diode of a pulse converter. Results: Energetical indicators were determined: power losses in a transformer, a controlled three–phase thyristor rectifier, an uncontrolled three-phase diode rectifier, an input filter of a pulse converter, an IGBT transistor and a reverse diode of a pulse converter. Based on the pursued assessment of the energetical indicators of power supply two options, it is concluded on feasibility of transformer-free circuit application in bearings’ position of vibration-acoustic diagnosis. Practical importance: A variant of an energy–efficient power supply for the position of indiscriminate vibroacoustic diagnosis is proposed, which includes an uncontrolled semiconductor rectifier and a pulse converter, accomplished using an IGBT transistor.