The family of MRFCs contains two topologies based on buck–boost,´Cuk, SEPIC and Zeta MRC and one topology based on the boost MRC[32–34]. A exemplary circuit of the first topology of buck–boostMRFC is shown in Fig. 7a. The static characteristics of MRFCs are similar to the characteristics of MRCs (Fig. 3b), with the difference that voltage gain depends on output frequency (Fig. 7b) [32]. It should be noted that in MRFC solutions the electrical energy stored in the reactance elements during period of input voltage frequency is equal zero. Unfortunately, MRFC requires many components due to the insertion of the boost-up reactors, capacitors and switches.