Suppression of Power Quality Problems by using MPC-Based UPQC Technique

Abstract

The main priority of electrical utilities is to supply their customers with an uninterrupted sinusoidal voltage of constant magnitude and frequency with balanced sinusoidal currents at the AC mains. However, the present day AC distribution systems are facing severe power problems such as voltage sags, voltage swells, reactive power burden, unbalanced loads, currents harmonics, spikes, surges, excessive neutral current, etc. These utilities are not able to procure eternal solutions to these aforementioned problems in the supply voltages across the load ends of the consumers. And these problems when left not overcome, could lead to damage of expensive devices, electric shock or electrocution of the human operators, disruption of important industrial processes, or even the total collapse of the electrical network system. This necessitated the development of different techniques for alleviating these problems to some certain extent. Many works have been done by different researchers and engineers in the realm of power quality improvement. But there still exist the power quality problems in all electrical power systems. In this research thesis, a new technique has been developed to suppress the power quality problems in a more improved way. Model Predictive Control based Unified Power Quality Conditioner is proposed to effectively serve as a single solution to multiple power quality problems. The choice of the UPQC over the other custom devices is because of the fact that it comprises of a series Derivative Voltage Restorer (DVR) which mitigates voltage related problems and a shunt Distributive Static Compensator (DSTATCOM) which handles the disturbances associated with currents. MPC is also selected with high preference over the other controllers due to its preview ability and capability of handling constraints and MIMO systems.