Dynamic Voltage Restorer for Voltage Sag Compensation Using Fuzzy Pi Controller

One of the major concerns in electricity industry today is power quality. It becomes especially important with the introduction of advanced and complicated devices, whose performance is very sensitive to the quality of power supply. The electronic devices are very sensitive to disturbances and thus industrial loads become less tolerant to power quality problems such as voltage dips, voltage sags, voltage flickers, harmonics and load unbalance etc. At present, a wide range of very flexible controllers, which capitalize on newly available power electronics components, are emerging for custom power applications. Among these, the distribution static compensator (D-STATCOM), dynamic voltage restorer (DVR) and unified power quality conditioner (UPQC) which is based on the VSC principle are used for power quality improvement. The main aim of my project is to design DVR which is used to compensate voltage quality problems and fuzzy logic controller is used to control the inverter. A new fuzzy PID controller is developed to improve the magnitude of load voltage. The results are compared with conventional controller. The results will be analyzed using mat lab / Simulink software.