Identifying Optimal Wind Penetration for Agricultural Distribution Networks: Integrated Power Quality and Reliability Analysis

This research presents a systematic analysis framework for wind farm integration in scaled IEEE 33-bus agricultural distribution systems (×26.38, representing 98 MW peak agricultural load), focusing on comprehensive power quality, reliability, and economic assessment. The scaled system exhibits baseline voltage violations (24 buses) characteristic of extended radial distribution topologies serving concentrated agricultural loads, consistent with real utility system characteristics in Indonesian agricultural regions. Four wind penetration scenarios (0%, 15%, 30%, 45%) are evaluated using an integrated backward-forward sweep methodology coupling fundamental power flow with empirical harmonic calculations validated against full harmonic load flow analysis (±0.3% accuracy). The analysis employs realistic harmonic injection models for VFD-dominated agricultural loads and full-converter wind turbines, time-domain operational profiles capturing diurnal variations, and revised reliability modeling incorporating protection coordination constraints and battery energy storage system limitations. Results demonstrate that 30% penetration achieves optimal multi-objective performance validated through systematic sensitivity analysis across 10-45% penetration levels: active power loss reduction of 35.5% (210.9 kW to 136.1 kW), harmonic distortion mitigation up to 46.1% THD_V reduction at the wind connection point (1.52% to 0.82%), and realistic reliability improvements of 5.0% SAIDI reduction (8.52 to 8.09 hours/year) accounting for islanding effectiveness constraints (19% successful islanding events with proper battery energy storage and protection infrastructure). The 45% penetration scenario introduces voltage regulation challenges (V_max = 1.052 p.u.) that offset incremental benefits. Economic analysis reveals that system-wide benefits (loss reduction: $670,000/year) substantially exceed agricultural productivity gains ($4,800/year with realistic nonlinear yield models), positioning wind integration as primarily a power quality and efficiency enhancement with supplementary agricultural reliability benefits. Practical implementation requires comprehensive voltage regulation equipment ($2.1-2.5M investment), harmonic filters for VFD-dominated buses ($240,000), and advanced protection schemes for islanding operation ($450,000-$700,000). The integrated analysis framework provides utilities and agricultural operators with quantitative guidance for optimal distributed generation deployment, balancing technical performance, economic viability, and operational constraints.