DESIGN OF CUSTOM POWER DEVICES FOR POWER QUALITY IMPROVEMENT USING FRACTIONAL ORDER PID CONTROLLER

摘要

Design of Custom Power Devices for Power Quality Improvement using Fractional order PID Controller ABSTRACT OF THE INVENTION Disclosed here in a Custom Power Device (CPD) to be known as Unified Power Quality Conditioner (UPQC), which is a combination of Dynamic Voltage Restorer (DVR), a series connected CPD and STATCOM, shunt connected CPD in cascade via a common dc link capacitor. DVR injects a voltage, which is added at the point of the common coupling (PCC) such that the loads end voltage remains unaffected by any voltage disturbance. The main functions of the STATCOM are to compensate for the load reactive power demand and unbalance, to eliminate the harmonics from the supply current, and to regulate the common dc link voltage. The invention associated with the development of UPQC control schemes using fractional PID controller for power quality improvement and implementation of a versatile control strategy to enhance the performance of UPQC. The invented control scheme gives better steady-state and dynamic response. The validity of the invented control method is verified by means of 2 kVA hardware UPQC prototype. The power compensator of the present invention reduces the system losses due to reactive power compensation and hence continuous power factor correction and requires less maintenance. It is also environment friendly and can easily be reinstated in any other location