Solid-State Inrush Current Limiter Controller Based on Inrush Prediction for Large Transformers

TL;DR

This paper introduces a novel solid-state inrush current limiter for large transformers that uses Kalman filtering for inrush prediction, effectively reducing inrush currents during magnetization.

Contribution

The paper presents a new SSICL design with a Kalman filter-based control strategy, tested through simulation and prototype experiments, enhancing inrush current suppression.

Findings

Significant reduction in transformer inrush current.

Successful implementation of Kalman filter-based control.

Effective prototype performance demonstrated.

Abstract

Inrush current problems of the industrial transformers are occasionally more serious than the utility transformers. A new Solid-State Inrush Current Limiter (SSICL) is proposed for medium voltage power transformers. The SSICL consists of three similar sets. Each set includes a bidirectional semiconductor switch and an inrush current limiter resistor. Using a control strategy based on Kalman filtering, transformer inrush current is suppressed during magnetization process. In fact, built up profile of the inrush current is dictated in accordance with the estimated current by a slow dynamic Kalman filter. A single-phase prototype SSICL is developed and tested. The proposed control scheme is simulated in MATLAB-SIMULINK. By using Real Time (RT) toolbox of the MATLAB software and a PCI_1711U, interrelationship between the SSICL and its controlling system is realized. Some experiments are carried out to evaluate the performance of the SSICL. The results show that the proposed SSICL can considerably suppress inrush current of the transformer