The paper presents a new approach that assists power system restoration planning with regards to control of temporary overvoltages (TOVs) due to transformer energization. The frequency-domain analysis in combination with analytical calculations is applied to find an optimum resonance condition. The analytical equations are based on sensitivity analysis for single frequencies and are extended to total sensitivity calculation. After an introduction of the phenomenon of overvoltages during power system restoration and harmonic resonance overvoltages, basic principles of their control are explained. Also, an algorithm is introduced for the results evaluation of harmonic resonance studies where it is necessary to perform simulations. The objective is to find a minimum time after which the simulation runs of temporary overvoltages can be terminated using short-time Fourier transform. Then the new algorithms are presented and demonstrated for a partial of 39-bus New England test system.