DC/DC converter with parallel input and parallel output with shared power switches and rectifier diodes

Abstract

A DC/DC converter with parallel input and parallel output circuit topology is presented to achieve the main features of reduced switch count and medium power level compared with conventional parallel half-bridge resonant converter. The proposed converter has three resonant circuits to share load currents and reduce the current stress of circuit components. These three resonant circuits use the same power switches to deliver power from input side to output load so that the switch counts are reduced compared with the conventional parallel resonant converter. The rectifier diodes at the secondary side of three resonant circuits are partially used in common so that the diode counts are also reduced. Since three resonant circuits are connected in parallel, the sizes of the transformers and active and passive components are reduced. The switching frequency of the proposed converter is operated to be less than the series resonant frequency. Thus, active switches are turned on under zero voltage switching and rectifier diodes are turned off under zero current switching. A 1.6 kW laboratory prototype is designed and constructed to demonstrate the feasibility and performance of the proposed circuit.

Bidirectional DC Converter with Frequency Control: Analysis and Implementation

“…From the given dead time, switching frequency, and input and output voltages, the magnetizing inductance Lm2 is obtained as: Although there are several approaches [18][19][20][21]…”

“…Since iQ3 < 0 and iLr > 0, the body diode DQ3 of MOSFET Q3 conducts so that MOSFET Q3 turns on after t0 to realize soft switching. In this mode, iLr(t0) + iLm1(t0) < 0, DQ1 is conducting, CH1 is charged by iDQ1, vab = VCH1 = VH/2, vLm2 = nVL, iLm2 increases with the slope nVL/Lm2 and iLm1 increases with the slope VH/(2Lm1 Although there are several approaches [18][19][20][21]…”

“…To reduce air pollution and climate change, renewable energy sources with power electronic conversion have been demanded and developed in recent years. Bidirectional power converters [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] have been developed for alternating current (ac) to direct current (dc) conversion and dc-dc conversion. In references [1][2][3][4][5][6][7], ac-dc bidirectional power converters are employed between an ac power source and dc bus voltage, and dc-ac bidirectional power converters are widely employed in ac drive systems.…”

Input parallel–output parallel connected modular nonisolated DC‐DC converters with current self‐sharing capability operating in discontinuous conduction mode

“…This paper will address the concept of self‐sharing in modular systems composed of nonisolated converters in DCM and in IPOP configuration, which can be used in dc‐dc sources and renewable systems. The mains contributions of this paper are highlighted as follows: Proposed and analyzed nonisolated dc‐dc converters (the literature just has isolated topologies 12,14,17,19,23,31–35 ); Self‐sharing of the currents among the modules without extras control loops; Proposal based on conventional converters; Simple implementation; Increase the power range of the conventional converters; The number of modules can be adjusted depending the applications and specifications. …”

“…• Proposed and analyzed nonisolated dc-dc converters (the literature just has isolated topologies 12,14,17,19,23,[31][32][33][34][35] ); • Self-sharing of the currents among the modules without extras control loops;…”