This paper addresses comparative investigation on the permanent magnet (PM) wind power generators' performance considering PM flux directions while generated electrical energy is being stored through a mechanical energy storage system (MESS). Radial-and axial-flux PM generators are dealt with, and since their equivalent circuit parameters are almost identical, their comparison can be reasonable. During the energy conversion through the MESS, since a power converter is required, the phase current of each generator contains harmonic components due to diode rectifier with high influence on the generators' performance. In this study, the electromagnetic characteristics of each generator are analyzed based on the measured current to consider the influence of those harmonics, and their performance evaluation is also performed by experiment.