Modeling and simulation for mitigation of voltage sags in variable frequency drives

In recent years, with the development of technology, significant progress has been experienced in the industrial field. Although these technological developments provide great convenience in industrial areas, they cause serious increases in the amount of energy consumed. Variable frequency drives are used in order to reduce the amount of energy consumed in industrial facilities. Although variable frequency drives are frequently used, they are extremely sensitive to power quality events. For this reason, the uninterrupted and continuous power supplied to the devices will increase energy efficiency along with the quality in the production process. In the literature, uninterrupted and continuous energy is explained together with the concept of power quality. The deterioration in power quality will adversely affect the production process in industrial facilities. Power quality problems can be basically defined as disturbances in current and voltage. One of the most common power quality problems is voltage sags. Variable frequency drives are adversely affected by these voltage sags. In this thesis, power quality problems occurring in an industrial facility and the effects of these problems on the facility are examined. By evaluating the existing methods in the literature, an active front end and energy storage based method, which is a hybrid method, has been developed and proposed. This proposed study is modeled with MATLAB/Simulink simulation program on variable frequency drives and applied in facility. As a result of this proposed study, all voltage sags that occur are prevented. This method has been found to be 44% more cost-effective than conventional methods.