Noncascading Quadratic Buck-Boost Converter for Photovoltaic Applications

Abstract

The development of switching converters to perform with the power processing of photovoltaic (PV) applications has been a topic receiving growing interest in recent years. This work presents a nonisolated buck-boost converter with a quadratic voltage conversion gain based on the I–IIA noncascading structure. The converter has a reduced component count and it is formed by a pair of L–C networks and two active switches, which are operated synchronously to achieve a wide conversion ratio and a quadratic dependence with the duty ratio. Additionally, the analysis using different sources and loads demonstrates the differences in the behavior of the converter, as well as the pertinence of including PV devices (current sources) into the analysis of new switching converter topologies for PV applications. In this work, the voltage conversion ratio, steady-state operating conditions and semiconductor stresses of the proposed converter are discussed in the context of PV applications. The operation of the converter in a PV scenario is verified by experimental results.

Implementation and reliability analysis of a new non‐isolated quadratic buck–boost converter using improved Markov modelling

“…The converters [14,15] have continuous input current but the converter in [14] utilizes a single switch but has high switching stress with a larger number of elements. The converters presented in [ [16,17]] do not have continuous input current and hence are not suitable for renewable energy applications.…”

“…Various authors have proposed converters both, inverting [2,[13][14][15][16][17][18] and non-inverting [19][20][21][22][23][24] type buck-boost converters in literature. A Cuk converter-based topology in [13] produces a higher gain in boost operation as compared to the conventional Cuk converter however the converter lacked a common ground.…”

“…The converter [18] has a continuous input current, produces a high gain but less than the proposed topology and the same as in [17], however due to a large number of elements it produces a lower gain per element. Most of the converters like the ones proposed in [14][15] and [22] including the TBBC and SEPIC converter, achieves unity gain at 50% duty cycle and operate in buck region for half the time. This buck mode is also a low output power zone and the proposed converter transitions from the buck mode at 26.8% duty cycle.…”

“…A Cuk converter-based topology in [13] produces a higher gain in boost operation as compared to the conventional Cuk converter however the converter lacked a common ground. Though the buck-boost converter suffers from higher switch stress [14,15], the converter in [16] produces low switching stress. The converter however suffered from discontinuous input current which inhibits its operation for renewable energy applications.…”

A Step-Up Converter with Large Voltage Gain and Low Voltage Rating on Capacitors

“…Several applications require a large voltage-gain DC-DC converter; one of the emerging applications is the generation of electricity from renewable energy sources, such as photovoltaic (PV) panels and fuel cell (FC) stacks. Power electronic converters are used to customize the electrical energy from those sources to the characteristics required to feed electrical appliances or inject power into the utility grid [1][2][3][4][5].…”