Search

In this article, the influence of the rotary transformer design parameters on the dynamic performance of the electrically excited synchronous machine (EESM) has been investigated. The model of EESM in the d-q reference frame with the control system has been built and analyzed using Matlab/Simulink software. The main electrical parameters of the rotary transformer were identified and implemented into the equivalent circuit model of EESM based on the parameters of the real machine. Based on the proposed model, the most suitable design parameters for the wireless excitation system were obtained.

In this article, the most common topologies of rotary transformers for wireless power transfer (WPT) will be presented. Their main advantages, disadvantages and applications will be discussed. The methodology for modeling of rotary transformers for wireless excitation of the electrically excited synchronous machines will be especially emphasized. Based on the literature review and the results obtained in the present study the recommendations for the rotary transformer design will be provided.

The paper deals with the wavelet transform potential for localization of leakages in the pumping complex pipeline network. The relationship of wave processes in the head signals and the change of the wavelet coefficients in the time and frequency domain are determined. It is proved that the beginning of the emergency mode corresponds to the first abrupt change in the root-mean-square values of the wavelet coefficients in the head signal. To identify the coordinate of the leakage in the pipeline network it is proposed to use the time moments of the first abrupt change of the root-mean-square values of the wavelet coefficients. It is found that the error of determining the location of a leakage is affected by the geometry of the pipeline, the speed of the shock wave propagation, the type of the leakage and its volume. The obtained theoretical results are confirmed experimentally in a pumping complex laboratory setup.

It is demonstrated that pump complexes pipeline networks are characterized by a high degree of breakdown rate because of leakages accompanied by complicated wave processes in the hydrosystem. It is found out that pipeline network wave processes depend on localization place and amount of the leakage, hydronetwork structural parameters as well as the properties of the transported liquid. Leakage influence on technological, electromechanical and energy characteristics of the pump complex is determined. It is stated that to identify the leakage it is expedient to use a signal of hydraulic power, whose frequency analysis makes it possible to obtain a wider spectrum of diagnostic signs of non-stationary condition. It is shown that leakage is accompanied by growth of hydraulic power variable component, in particular, its sine component.