###### Abstract
Also, their size and response time increases as high-order passive components are present in the z-source circuit arrangement. These drawbacks are tackled in the converters as reported in [14; 15]. They are realized without involving the RC or z-source circuit for safe commutation but their non-inverting and inverting operations are non-identical. The converters represented in [16; 17] tackle the non-identical operations of the preceding converters. The converters having positive and negative voltage gain may also be employed as frequency controllers as discussed in [18]. Their power quality during inverting operation is poor as that of non-inverting operation as their operating modes are non-symmetrical. The symmetrical operating modes are obtained in [19] but this topology has the problem of high conversion losses as it can only be realized in buck-boost fashion. The conversion efficiency is improved in [20] by enabling the buck and boost operation with a voltage gain of dual polarities. The converters presented in [18; 19; 20] can be effectively operated in low-frequency operation but switching techniques in their high-frequency operation become complicated that reduces their potency in frequency boost operation. A simple switching algorithm is proposed in [21] for induction heating systems but it faces the challenge of a large number of switching units. The number of switching units is reduced in [22] with a similar switching scheme. The harmonic issues in direct ac voltage and frequency converters are reported in [23] to evaluate their performance with other power converting topologies. A compact power converting topology as depicted in Figure 1 is reported in [24] to lower the conduction losses by reducing the number of switching units. This topology is unable to realize without a bulky center-tapped transformer that is operated at low grid frequency. Its use not only increases the overall size and cost but also leads toward the core saturation issue owing to the flow of unidirectional currents or low-frequency currents in outputs windings. Also, there is a shoot-through issue especially one output frequency requirement is much higher than that of input standard frequency due to the complementary switching structure of the controlled switching units \"\(Q_{1}\)\" and \"\(Q_{2}\).\"  
In viewing the above issues reported in the preceding research articles, a new transformer -less direct AC-AC power converting topology is suggested and has the following attractive characteristics. * It has no core saturation issue and no core losses, as the proposed topology is directly connected to the grid supply. This elimination decreases the overall volume and improves conversion efficiency. * An intermediate inductor ensures the shoot-through challenge once complementary operated switching units are turned on at the same time. The shoot-through or overlapping intervals may be employed to increase the boost factor during the frequency step-up operation. * Any low-cost PWM controller may be employed due to the use of simple switching techniques. * All operating modes are realized at zero voltage switching in frequency regulation modes. For the sake of organizing this research article, Section 2 investigates the operating modes for voltage and frequency control with the help of switching signals. A comparison of the performance characteristics of the proposed topology with the existing converters is addressed in Section 3. Section 4 illustrates the effectiveness of the developed topology by using simulation and practical results. Section 5 highlights the conclusion.