Comparative analysis of trolley busbar parameters of different geometric shapes under the condition of higher current harmonics

Modern workshop power supply systems can have a significant length. Therefore, their parameters and electrical characteristics have a significant impact on power quality, operation modes of electrical consumers and energy efficiency of technological processes. Available in engineering practice methods of calculation of parameters and characteristics of bus ducts are based on methods of circuit modeling. Circuit parameters are usually determined on the basis of generalized equations. These equations are derived from a number of assumptions, which limits the scope of their use. Alternative methods, based on empirical dependencies, can be used to calculate the electrical parameters and characteristics based on field modeling. Thus, the paper proposes a mathematical two-dimensional field model of electromagnetic processes in the frequency statement of the problem, allowing with high accuracy and efficiency of numerical implementation to decompose electromagnetic processes in the active elements of the trolley busduct and for each relevant amplitude and frequency of the k-th harmonic current to determine the electromagnetic parameters. busduct with regard to their design features, nonlinearity of magnetic and electrical properties of materials, the skin effect, the blitz effect. A general analysis of active and inductive resistances of busduct phase trolleys depending on their shape, material and current harmonic spectrum is performed. The level of asymmetry of busbar parameters caused by proximity effects, surface effects, skin effects and other edge effects is given. It is found that in the presence of higher current harmonics, the parameters (active and reactive supports) of busbar trolley do not depend on the amplitude of k current harmonics, but depend only on their frequency. The level of voltage drop asymmetry for all forms of phase trolley busducts is caused by the asymmetry of their parameters. Among investigated L, W-, I-, U, X-forms of bus duct trolleys it was found that the most optimal form of steel and copper bus duct trolleys is the angular form of trolleys (L-form), which provides the least increment of active and reactive resistance of bus duct trolley, current harmonics, as well as the minimum level of their asymmetry between phases of bus duct trolleys.