Increasing penetration of distributed energy storage systems, and power electronic converter(PEC)-based industrial loads has intensified power quality(PQ) challenges in modern distribution networks. To address these issues, this paper presents an Adaptive Least Mean Square(ALMS)-controlled Unified Power Quality Conditioner(UPQC) employing conventional twelve-switch and proposed reduced ten and nine-switch voltage source inverter (VSI) topologies. Proposed configurations integrate functionalities of both Distribution Static Compensator (DSTATCOM) and Dynamic Voltage Restorer(DVR) to provide simultaneous shunt and series compensation for mitigating voltage and current-related PQ disturbances. Furthermore, solar-photovoltaic(PV) system integrated with an Incremental Conductance(INC)-based Maximum Power Point Tracking(MPPT) algorithm. The proposed reduced-switch topologies are designed to minimize semiconductor device count, enhance semiconductor utilization, and reduce converter cost without compromising compensation capability or increasing switch-VA ratings. A comparative analysis among twelve-switch, ten-switch and nine-switch UPQC configurations is carried out interms of source current harmonic mitigation, power-factor improvement, voltage regulation, balancing and sag/swell compensation in compliance with IEEE 519–2022 standards. In addition, switching and conduction loss analyses are performed to evaluate converter performance. The results reveal that proposed ten-switch and nine-switch UPQC configurations reduce switching losses by 13.21% and 12.18%, conduction losses by 8.69% and 4.27% and overall converter losses by 21.9% and 16.45%, respectively, compared with conventional twelve-switch topology. Moreover proposed nine-switch topology achieves highest efficiency of 92.26% followed by the ten-switch topology with 91.82%, compared to 90.91% for the conventional twelve-switch UPQC. Simulation studies in MATLAB/Simulink and real-time validation using OPAL-RT platform confirm the effectiveness, reliability and practical feasibility of proposed ALMS-controlled UPQC configurations. Developed system is suitable for renewable energy-integrated distribution networks, industrial power systems and electric vehicle charging infrastructures requiring cost-effective and efficient PQ enhancement.