An Algorithm for Controlling a Traction Asynchronous Drive That Minimizes Electrical Power Losses

Abstract

The article discusses the improvement of traction and energy performance main-line locomotives due to more complete use of possibilities of flexible microprocessor control and efficient algorithm that provides reduction of electrical losses in the traction asynchronous drive over the entire range working capacity. In the best way for a promising loco is tract with using a traction asynchronous drive. Such kind of tract drives allow completely use of the coupling mass of loco compares with collector track drive, due to the absence of a collector it is possible to increase the active length of the rotor and high reliability which makes it possible to realize increased axial power

Computational methods for studying the thermal state of frequency-controlled asynchronous traction motors

“…where 𝛼𝛼 1 is the coefficient of heat transfer from the surface of the engine. 𝐾𝐾 -a coefficient that takes into account that part of the losses in the stator core and in the grooved part of the winding, When calculating the thermal state of an asynchronous motor powered by a semiconductor frequency converter with an autonomous control inverter at rated load, the range of voltage and frequency changes is taken into account [2,3,5].…”

“…For each elementary node, a heat balance equation was compiled, which has the form: The model takes into account the conditions of forced convection from the main cooling surfaces of the engine and free convection from the bed and bearing shields to the ambient air. For each elementary node, a heat balance equation was compiled, having the form [1,3,4].…”

“…Increased heating due to power losses when powered by voltage which is different from the sinusoidal one leads to an increase in losses by 29% [1,2].…”

“…In traction mode, locomotives with asynchronous drive increase the likelihood of overheating of the traction engine structural elements. The consequences of overheating are: breakdowns of the insulation of the windings, inter-turn short circuits in the stator windings, accelerated aging of the insulation, which leads to a reduction in service life [1][2][3]. Asynchronous drive electric motor (ADEM) overheating also occurs when the engine is running in idle, traction and braking modes.…”