An increasing amount of consumed electrical energy is subjected to its characteristic parameter conversion, such as frequency, voltage value, etc. Therefore, it is also necessary in an increasing degree in all the stages of frequency conversion process to clear up and use most natural and direct ways to ensure electrical energy conversion efficiency, cost effectiveness and environmental protection. Such conversion stages under investigation might be: the type of conversion: single (direct conversion) or two-fold (rectifier-inverter type); the form of a desirable ideal conversion process: sinusoidal or non-sinusoidal; possible ways of approximation: rough rectangular approximation or a more sophisticated mode; voltage regulation possibilities; etc. In order to find a solution we have chosen AC/AC direct frequency conversion, analyzed the sinusoidal frequency conversion process, approximated each modulated input voltage (but not the sinusoidal modulating function as in cycloconversion) and used all instantaneous input voltage values for the adjustment of output voltage formation. This is why we have come to alternative direct frequency conversion process investigation, which is the main subject of this report.