This paper presents a novel soft-switching boost DC-DC converter, which uses an edge-resonant switch capacitor based on the pulse width modulation PWM technique. These converters have high gain voltage due to coupled inductors, which work as a transformer, while the boost converter works as a resonant inductor. Upon turning on, the studied soft switching circuit works at zero-current soft switching (ZCS), and upon turning off, it works at zero-voltage soft switching (ZVS) while using active semiconductor switches. High efficiency and low losses are obtained while using soft switching and auxiliary edge resonance to get a high step-up voltage ratio. A prototype model is implemented in the Power Electronics Laboratory, Assiut University, Egypt. Seventy-two-panel PV modules of 250 W each were used to simulate and execute the setup to examine the proposed boost converter.Energies 2020, 13, 749 2 of 17 achieved by adding an auxiliary circuit, as shown in Figure 1a, instead of a classical hard-switched converter [6]. Moreover, the auxiliary circuit has no additional complexity or cost.To reduce the weight and size, a higher switching frequency operation, i.e., in the range of more than 50 kHz, is utilized [7]. In traditional switching converters, the exemplary switching frequency is between 5 kHz and 20 kHz. The switching frequency generally cannot be increased because this results in increasing switching losses and stresses on semiconductor devices. A high frequency is utilized to reduce the volume and weight of passive devices. The dynamic performance is better in the case of higher frequencies. High-frequency switching speeds up the converter response time and reduces the output filter volume, cost, and size. A high switching frequency is desirable for the minimum output inductor size and maximum control loop bandwidth. Overall system size will be reduced due to the operation of switches at a high frequency, which will make the new converters more feasible.To overcome these problems, soft-switching schemes such as zero-voltage soft switching (ZVS) type or zero-current soft switching (ZCS) commutation should be utilized to reduce switching losses and the semiconductor device stresses. For power converters in a distributed PV system, a soft-switching technique is proposed [8][9][10][11][12]. The presented converter (see Figure 1b) has advantages of improved efficiency at a higher switching frequency, low leakage current, wide load range, reduced weight and size, and a maximum total efficiency of 97.1% at a switching frequency of 100 kHz.The problems of excessive electromagnetic interference EMI and low efficiency can be solved by using zero-voltage-transition (ZVT) converters by limiting the turning-off di/dt in the output-side rectifier. Various types of ZVT converters have been presented before [9,13], but these converters suffer from several drawbacks, such as the following.