Abstract Mitigation and adaptation to climate change have been major driving forces in modernizing electric power infrastructure. Low quality has a significant impact on electrical equipment efficiency. Voltage unbalances one of the issues with low quality. This study used simulation method for supply voltage unbalance evaluate effect performance 3-phase transformers. The research results show ...

Three phase supply system is found to be quite balanced in both magnitude and displacement at the generation levels but it is not so at distribution end. Voltage unbalance which is a common and global phenomenon is found to be very effective in deteriorating the performance of electrical apparatus at user end. Such environment badly affects the performance of induction motors, an important clas...

Power quality test facilities developed at the University of Wollongong include a 10kVA waveform generator (WG) of which the detailed design and operation has been described previously. The WG is essentially a programmable IGBT voltage source inverter controlled by a micro-controller. The original intention of this generator was to test electrical equipment under the influence of harmonic disto...

Three-phase power systems under sinusoidal steady-state condition are commonly analyzed by means of the wellknown symmetrical component transformation. The main assumption underlying such a transformation is symmetry of the phases of a power system. In modern power systems, however, phase symmetry cannot be guaranteed for several reasons, e.g., large single-phase loads including high-speed rail...

The term ‘power quality’ [1-2] refers to the purity of the voltage and current wave-form, and a power quality disturbance is a deviation from the pure sinusoidal form. Harmonics superimposed on the fundamental are one cause of such deviations. Power quality problems [1-2] like voltage harmonics, voltage flickers, voltage sags and voltage swells, current harmonics, current unbalance, reactive cu...

This paper presents a novel approach to determinethe power system stability using resistive superconducting faultcurrent limiter (SFCL) of an electric power grid (EPG). Inaddition, the electric railwaysystem has rapidly changing loadcharacteristics in time. An unbalance is generated owing to therapidly changing large single-phase loads. Subsequently, the unbalanced load causes an unbalanced tra...

In this paper, we investigate the control of inverter-based resources (IBRs) for optimal voltage unbalance attenuation (OVUA). This problem is formulated as an optimization program under a tailored dq-frame, which minimizes negative-sequence at point common coupling (PCC) subject to current, active power, synchronization stability, and feasibility constraints. The inherently nonconvex intractab...