An Approach to Steady-State Power Transformer Modeling Considering Direct Current Resistance Test Measurements

Abstract

Measurements obtained in transformer tests are routinely used for computing associated steady-state model parameters, which can then be used for load flow simulation and other modeling applications. The short circuit and open circuit tests are most commonly performed with this purpose, allowing estimation of series and parallel branch transformer parameters. In this study, an extended model is proposed which does not employ the usually assumed cantilever circuit approximation and explicitly accounts for transformer connection resistance. An estimation of the proposed model parameters is enabled by usage of additional measurements yielded by the direct current (DC) resistance test. The proposed approach is validated by means of an experiment carried out on a real distribution power transformer, whose results demonstrate that the proposed model and parameter computation approach effectively decompose total transformer resistance into winding and contact components. Furthermore, the numerical results show that contact resistance is not negligible especially for low voltage windings, which reinforces the usefulness of the proposed model in providing detailed modeling of transformer resistances.

Importancia estratégica de un sistema de alta corriente en baja tensión en el sector eléctrico Colombiano

“…Las simulaciones validadas requieren la comprensión física detallada de los fenómenos electromagnéticos y la sensibilidad de los parámetros y variables que intervienen en las pruebas (Curcanu et al, 2007;Delgado et al, 2017;Parise y Scarpino, 2021), así como de exigentes requerimientos de validación por parte de los laboratorios, lo que dificulta su aplicación. Además, las simulaciones requieren el desarrollo de modelos complejos de los componentes del sistema y equipos bajo prueba como transformadores (Aponte et al, 2011;Cerón et al, 2020;Pires Corrêa y Teles Vieira, 2021), interruptores (Chmielewski et al, 2017;Szulborski et al, 2021), entre otros. En el caso del suroccidente colombiano se realizó la validación de un software mediante mediciones realizadas en laboratorio (Díaz et al, 2016).…”

Simulation optimal and design of 3-kW DC-DC converter for pure electric vehicles

“…39 The structure of the transformer winding would have an impact on the transformer due to the existence of AC impedance. 40 The uncrossed winding structure and the winding structure of the complete cross are shown in Figure 21. Yellow represents the primary winding, white represents the insulation layer, and blue represents the secondary winding in Figure 21.…”