A Comprehensive Review on Power Loss Reduction and THD Mitigation in Low and High Voltage Distribution Systems

Abstract

The growing need for reliable and efficient power distribution has once again brought forth issues regarding power quality and technical losses in electrical networks. Because of their long lowtension lines and unbalanced nonlinear loads, conventional Low Voltage Distribution Systems (LVDSs) are mostly subjected to high I²R losses, voltage drops, and high Total Harmonic Distortion (THD). On the contrary, High Voltage Distribution Systems (HVDSs) place the 11 kV network closer to consumer clusters, keeping smaller transformers nearby. Hence, there are fewer line losses, good voltage regulation, and power theft mitigation. This review paper presents a detailed assessment of existing work in the literature on comparisons between LVDSs and HVDSs with respect to efficiency, voltage stability, reliability, and THD performances. Recent developments in MATLAB/SIMULINK-based modelling and field implementations are critically studied so as to emphasise the basic parameters influencing system performance. The paper discusses network design, conductor sizing, load segregation, and harmonic filtering towards optimised power delivery. It also underscores the interfacing of renewable energy sources such as solar and wind into distribution systems while looking into the implications on power losses and harmonic behaviour. Various case studies have revealed that HVDSs can reduce technical losses by 30–50% and attain improved THD levels as compared to LVDSs, thereby playing a vital role in the evolution of smart grids. However, a fair share of issues regarding the enormous initial capital investment, logistics of maintenance, and harmonics from distributed generation still remain to be resolved. The review finally draws attention to the synergy of modelling, real-time monitoring, and adaptive control strategies needed for sustainable and high-quality power distribution in ever-evolving LVDS and HVDS networks.