Non-Isolated High Step-Up DC/DC Converter With Coupled Inductor and Switched Capacitor

Abstract

In this paper, a high-efficiency DC/DC converter with low voltage stress is designed for green power applications. The proposed non-isolated high step-up DC/DC converter combines the advantages of switched capacitors, coupling inductors, and voltage multiplier techniques. Adding the cells of the switched capacitor not only increases the voltage gain but reduces the voltage stress of the semiconductor devices. High voltage gain can be achieved by adding a coupled inductor method to adjust the turns ratio. When these are combined with a voltage multiplier circuit, the leakage energy of the coupled inductor is recirculated to the output terminal with lossless passive clamping performance. The leakage inductance of the coupled inductor controls the current dropping rate of the output diode turn OFF so that the reverse-recovery problem is mitigated. The proposed converter integrates these three techniques to achieve high voltage gain without operating at maximum duty cycle. In addition, switching loss reduction is realized through zero current switching turn ON soft switching performance with low voltage stress of semiconductor devices. Finally, this paper verifies the performance of the proposed converter for theoretical analysis by using a 35~45V input, 380V output, and 1kW power prototype circuit. INDEX TERMS Boost converter, high step-up, coupled inductor, switched capacitor, voltage multiplier cell.

Nonisolated high step‐up DC‐DC interleaved SEPIC converter based on voltage multiplier cells

“…Nonisolated high step-up dc-dc converters have become a hot topic in the recent literature considering that one can increase the voltage gain without using transformers in practical applications that do not demand galvanic isolation. 1 Typical examples include dc microgrids, motor drives, electric vehicles (EVs), uninterruptible power systems (UPSs), and especially renewable energy conversion systems. 2 According to Forouzesh et al, 3 there are several solutions for extending the voltage gain, that is, switched capacitors (charge pumps), switched inductors, voltage lift, coupled inductors, cascade association, and voltage multiplier cells (VMCs).…”

“…Nonisolated high step‐up dc‐dc converters have become a hot topic in the recent literature considering that one can increase the voltage gain without using transformers in practical applications that do not demand galvanic isolation 1 . Typical examples include dc microgrids, motor drives, electric vehicles (EVs), uninterruptible power systems (UPSs), and especially renewable energy conversion systems 2 .…”

A single‐switch high‐gain DC–DC converter for photovoltaic applications

“…However, this converter has a high input current ripple. A nonisolated converter based on SC and voltage multiplier techniques is implemented in Seo et al 20 The switch operates under ZCS condition, and gain can be increased by increasing the number of SC cells which is a disadvantage. High gain is achieved by combining a coupled inductor and a voltage multiplier.…”

Non-Isolated DC–DC Power Converter With High Gain and Inverting Capability

“…Moreover, two input boost stages are used. To lessen the VM stages, a new interleaved converter with a Dickson voltage multiplier is proposed [21][22][23][24][25][26][27][28][29][30]. However, the limitations with these DC-DC converter topologies are, circuit complexity, a higher number of VM stages, unable to attain high gain with inverting capability, higher input ripples, etc., In this paper, for achieving the low current ripple at the input side, high voltage gain, and current fed configuration using a minimum number of components and stages, a new nonisolated current fed interleaved multilevel interleaved boost converter.…”