Analysis of Short-Circuit Impedance in Multi-Winding Transformer

Abstract

Due to green energy policies, investments in renewable energy are rapidly increasing, which in turn raises the demand for efficient power plant integration into electrical grids. Multi-winding distribution transformers are crucial in this process, as they enable operation at various voltage levels to match different grid requirements. However, designing such transformers, mainly calculating short-circuit impedance in accordance with industry standards, is a highly complex and challenging task when using conventional analytical methods. This study investigates the short-circuit impedance of a multi-winding transformer and presents an efficient approach to accurately calculating the short-circuit impedance. The study uses Finite Element Method simulations to calculate the short-circuit impedance for different winding configurations. Experimental testing is performed on a prototype transformer to validate the results, ensuring its performance and reliability. The proposed method offers researchers and manufacturers a reliable approach to accurately determine short-circuit characteristics, improving transformer design and reducing reliance on costly test processes. This approach supports the determination of the necessary characteristics of the transformer before producing prototypes

Keywords

• Transformer
• Multi-Winding
• Short Circuit Impedance
• Test
• Simulation

References

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