Design and analysis of a high step‐up single‐switch coupled inductor DC‐DC converter with low‐voltage stress on components for PV power application

Abstract

This paper presents a single-switch, high step-up, non-isolated DC-DC converter for photovoltaic (PV) power application. The proposed converter is composed of a coupled inductor, a passive clamp circuit, a voltage multiplier cell, and a voltage lift circuit. The passive clamp circuit recovers the leakage inductance energy of the coupled inductor and limits the voltage spike on the switch. Configuration of the passive clamp and voltage multiplier circuits increases the converter voltage gain. High-voltage gain without a large duty cycle, low turn ratio of the coupled inductor, low-voltage stress on the switch and diodes, leakage inductance energy recovery, and high efficiency are the main merits of the suggested DC-DC converter. Steady-state operation of the converter in continuous conduction mode (CCM), discontinuous conduction mode (DCM), and boundary condition mode (BCM) is discussed and analyzed in detail. Then, design procedure of the proposed converter is given. The presented DC-DC converter is compared with similar topologies to verify its advantages. Moreover, theoretical efficiency of the presented converter is calculated in details. Finally, simulation and experimental measurement results of 388 V-220 W prototype of the proposed DC-DC converter at 50-kHz switching frequency are presented to verify its performance.

Single switch quadratic boost converter with continuous input current for high voltage applications

“…Therefore, the value of coupling coefficient can be assumed unity. The ideal voltage gain of the proposed converter at k = 1 is derived as (22).…”

“…The coupled inductor and voltage multiplier techniques are combined in Ajami et al 14 and Axelrod et al 15 In spite of the fact that the converters in the previous studies [11][12][13][14][15] provide a high voltage gain and limit voltage spike on the switches, their input current is discontinuous with a high ripple. Therefore, in the previous studies, [16][17][18][19][20][21][22] some DC-DC converters with continuous input current and low switch voltage stress are introduced. Nevertheless, a high turn ratio and duty cycle are needed to achieve a very high step-up voltage gain in these converters.…”

Two‐ and three‐winding coupled‐inductor‐based high step‐up DC–DC converters for sustainable energy applications

“…Moreover, it should be considered that using a higher turn ratio to achieve a higher voltage gain causes higher electromagnetic interference noise and power losses. Recently, some high step-up DC-DC converters based on two-winding coupled inductor (2WCI) are presented in [8][9][10][11][12][13][14][15][16][17]. Moreover, several recent high step-up DC-DC converters with three-winding coupled inductor (3WCI) have been presented in [18][19][20][21][22], which leads to having more flexible regulation on voltage stress and voltage gain.…”

Analysis and implementation of a boost DC–DC converter with high voltage gain and continuous input current

“…However, by adding a clamp circuit, the number of devices is increased, which leads to an increase in the converter size and cost [21]. The coupled inductor and voltage multiplier circuit are combined to provide a highvoltage conversion ratio [22][23][24]. These converters are highperformance circuits with low cost and simple structures, which usually include diodes and capacitors to increase DC voltage [25].…”