This paper analyzes the fundamental power factor (FPF) of a diode rectifier-connected permanent magnet synchronous generator (PMSG) used in a motor-generator grid-connected wind energy system. The analysis is conducted using fast Fourier transform (FFT) investigation of currents and voltages of the PMSG. The PMSG’s FPF is investigated under various wind speeds using MATLAB/Simulink and Motor-CAD. The simulation results are validated through experimental measurements on a 4.2-kW PMSG. The findings demonstrate that, although diode rectifier-connected PMSGs are commonly assumed to have a unity FPF, they exhibit deviations from unity.