This paper presents a flexible harmonic domain (FHD) model of a grid-connected solar PV system amenable to harmonic analysis. The system consists of a 4.12 kW solar photovoltaic array that provides supply continuity and reliability for unmanned aerial vehicle (UAV) ground control station. The proposed system consists of a solar array, a boost converter, a three-phase inverter, and a three-phase filter. FHD technique is used to model the system, as it accounts only for dominant frequencies which enables obtaining of compact yet precise description of the system's harmonic interactions. Compared to complexity, extra harmonic extraction routines, and large computational resources of the time domain technique (TD), FHD needs only one matrix inversion to obtain both the voltage/current waveforms and harmonic content of each part of the system. The obtained results prove the feasibility, accuracy, and simplicity of the proposed FHD technique for modeling switched devices while maintaining the computational resources. For each part/state of the proposed system, both the waveform and its harmonic content are visualized.