Calculation of instantaneous line current of a three-phase network with an isolated neutral

Abstract

The article focuses on the study of methods for calculating instantaneous line currents in a three-phase network with an isolated neutral, which is critical for improving the reliability, efficiency, and accuracy of monitoring and diagnostics of electrical systems. The developed method extends the capabilities of standard approaches to diagnostics and analysis, and it allows for more accurate analysis of instantaneous parameters in electrical networks and detection of faults in the operation of high-voltage electrical installations. The study used an integrated approach to analyzing and modeling the operating and emergency modes of a subway traction substation using a three-phase rectifier. Detailed power supply modeling and analysis of the harmonic components of line currents and voltages in the high-voltage network were performed. Various operating scenarios are modeled, including normal and emergency conditions when one of the diodes in the rectifier fails. It was found that the harmonic composition has significant changes in the event of a diode failure, which can be used to diagnose the condition of the equipment. The results can be used to optimize the design, operation, and maintenance processes in the urban electric transport sector and other industrial systems, reduce the risk of unforeseen accidents, and ensure the stability of electricity supply. Modeling has shown the effectiveness of the proposed method for detecting emergencies and improving the efficiency of traction substation maintenance. The proposed recommendations will help to improve the efficiency, energy efficiency, and reliability of electrical systems, in particular in the industrial sector and large infrastructure projects, providing a more stable and secure power supply.