Design, analysis and experimental verification of a high voltage gain and high‐efficiency DC–DC converter for photovoltaic applications

Abstract

With the rapid development of photovoltaic systems, high step-up dc-dc converters draw significant attention, which shows the design challenges for simple topology, high efficiency, reduce voltage stress, and long lifespan. This study proposes a new high voltage gain converter that utilises the primary boost conversion cell and integrates with both switched-capacitor and coupled-inductor techniques. The proposed topology is modular and extendable for ultra-high step-up voltage gain. The leakage energy is recycled by a clamp circuit to minimise the switch voltage stress and power loss. One distinctive feature is that the voltage stress on the diodes and switch becomes low as well as constant against the variation of the duty cycle. Furthermore, the coupled inductor alleviates the diodes reverse recovery losses. The steady-state analyses, operation principles, and design guidelines are presented comprehensively. A prototype circuit is constructed to test the maximum power point tracking operation with voltage conversion from 30 to 380 V at 300 W. Experimental results substantiate the theoretical analysis and claimed advantages. The proposed converter demonstrates maximum power point tracking capability and high conversion efficiency over a wide range of power. The prototype shows the weighted efficiency of 96.3% according to the EU standard.

Ultra-High Step-Up DC-DC Converters Based on Center-Tapped Inductors

“…The equivalent circuit of the Pro4 converter during switch OFF-state (Mode 2) should be analyzed to obtain switch voltage stress. According to (15), (16) and Fig. 4(b), the switch voltage stress can be calculated as…”

“…Reduced input current ripple and continuous input current are the vital specifications of the converters that are utilized in renewable energy-based systems due to the harmful impacts of large and pulsating input current on the energy interfaces. The converters introduced in [12]- [16] suffer from large input current ripple owing to their inputside CI. Adopting interleaving technique and avoiding input CI are the effective solutions for the input current ripple problem.…”

A Single Switch High Step-Up DC-DC Converter Based on Tri-Winding Coupled Inductor for Renewable Energy Applications

“…However, these converters suffer from low efficiency, a high number of components, and higher maximum voltage stress on switches and diodes. Reference [22] suggested converters based on the coupled inductor, and clamp circuits are used in their structure in order to reduce the voltage stress of the main switch, However, the main downside of the converters proposed in Reference [23,24] is that high boost factor can be obtained in higher duty cycle and higher number of turns ratio. In References [25][26][27][28], TWCL is used for enhancing the voltage gain.…”

A high step‐up interleaved boost‐Cuk converter with integrated magnetic coupled inductors

“…In order to provide a sufficiently high voltage to the post-stage inverter, a DC-DC converter with a high step-up ratio is indispensable. Therefore, it is very important to study high step-up, highefficiency DC-DC converters [1][2][3][4].…”