Control strategies for unified power quality conditioner to mitigate voltage sag due to large motor starting during fault

Abstract

As induction motors are the heart of industrial industries for electromechanical conversion, voltage sags during large motor starting have become the most frequent Power Quality (PQ) problem. Induction motors are one of the most prominent sources of voltage sag problem. These disturbances can cause loads that re sensitive to voltage in buildings or factories to malfunction, contributing to the deterioration of power quality in industrial power systems or utility. The Unified Power Quality Conditioner (UPQC), which incorporates a series and shunt active filter capable of compensating supply voltage sag, swell, current imbalance, harmonics, and reactive power, is one of the devices that will combat voltage sag occurrence. The goal of this project is to develop several control techniques for the UPQC in order to overcome voltage sag caused by large motor starting during a failure. UPQC's Active Power Filters (APFs) are linked to the system through series and shunt transformers. The voltage swell is then injected through the source, and various sorts of faults are simulated to produce the voltage sag at the Point of Common Coupling (PCC). The switching pulses are created using a Proportional Integral (PI) controller, which compares the observed load voltages to the reference voltages. The measured source currents, on the other hand, are compared to their reference values, and the shunt APF switching pulses are generated using a hysteresis band controller. The suggested model is implemented in MatLAB Simulink and is anticipated to include voltage sag/swell compensation capabilities, as well as the capacity to maintain load voltage constant.