Pires Corrêa Henrique, Henrique Teles Vieira Flávio
Information and Communication Engineering Group (INCOMM), School of Electrical, Mechanical and Computer Engineering (EMC), Federal University of Goiás (UFG), Goiania 74605-010, Brazil.
Sensors (Basel). 2021 Sep 19;21(18):6284. doi: 10.3390/s21186284.
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.
变压器测试中获得的测量值通常用于计算相关的稳态模型参数，这些参数随后可用于潮流模拟和其他建模应用。短路和开路测试最常为此目的进行，以便估计变压器的串联和并联支路参数。在本研究中，提出了一种扩展模型，该模型不采用通常假设的悬臂电路近似，而是明确考虑了变压器的连接电阻。通过使用直流（DC）电阻测试产生的额外测量值，可以对所提出模型的参数进行估计。通过在一台实际配电电力变压器上进行的实验对所提出的方法进行了验证，实验结果表明所提出的模型和参数计算方法有效地将变压器总电阻分解为绕组电阻和接触电阻分量。此外，数值结果表明，接触电阻不可忽略，特别是对于低压绕组，这进一步证明了所提出模型在提供变压器电阻详细建模方面的有用性。
