Lakshmi, Shubh2019-12-302023-10-202019-12-302023-10-202019ROLL NO.156102013https://gyan.iitg.ac.in/handle/123456789/1389Supervisor: Sanjib GangulyThe compensators are widely used in the distribution networks to improve their steady-state operational performance, such as energy efficiency and bus voltage. The capacitor bank, voltage regulator, on-load tap changer etc., are traditionally used as compensators. However, the optimal placement of these does not ensure desired power quality (PQ) level. The custom power devices are group of compensators which can mitigate PQ issues and provide reactive power compensation. Thus, their optimal allocation in distribution networks can ensure desired PQ level and improve energy efficiency. UPQC is a versatile custom power device, which can simultaneously inject a series voltage and a shunt compensating current by using its series and shunt inverters, respectively to provide reactive power compensation and to mitigate PQ problems. In UPQC, the series and shunt inverters are connected to a common DC-link. An open UPQC (UPQC-O) topology, in which, the series and shunt inverters can be placed in different locations and they do not share a common DC-link, is used in this thesis to improve the operational performance of distribution networks. This needs the modelling of UPQC-O and the formulation of planning approach to optimally allocate in distribution networks.enELECTRONICS AND ELECTRICAL ENGINEERINGThesis