DCM-Based Zero-Voltage Switching Control of a Bidirectional DC–DC Converter With Variable Switching Frequency

Abstract

This paper investigates a control approach for achieving reliable zero-voltage switching transitions within the entire operating range of a conventional nonisolated bidirectional dc-dc converter that utilizes synchronous rectification. The approach is based on operation in the discontinuous conduction mode with a constant reversed current of sufficient amplitude, which is achieved by load-dependent variation of the switching frequency. This paper focuses on the obtained resonant voltage transitions and provides analytical models for determining the reversed current and timing parameters that would ensure safe, reliable and highly efficient operation of the converter. In addition, the proposed approach solves the synchronous transistor's spurious turn-on and body diode reverse recovery induced issues, does not require any additional components or circuitry for its realization, and can be entirely implemented within a digital signal controller. The effectiveness and performance of the presented control approach was confirmed in a 1-kW experimental bidirectional dc-dc converter that achieved 97% efficiency over a wide range of output powers at switching frequencies above 100 kHz.

Design and implementation of a zero voltage transition bidirectional DC‐DC converter for DC traction vehicles

“…Here, we compared the previous soft‐switched topologies especially the non‐isolated bidirectional DC‐DC converters in order to show the performance of the proposed circuit. A non‐isolated BDC has obtained 96% efficiency at 100 W. The reported topology operated under 20‐kHz switching frequency at 200‐W output power has obtained efficiency of 96% and 92% in boost and buck modes, respectively.…”

“…Currently, the research on converters is focused on developing highly efficient and reliable converters with minimized dynamical losses. There are discontinuous conduction mode control techniques that have been implemented on hard‐switched non‐isolated converters by soft switching with the implementation of nonlinear control strategy . The zero voltage switching (ZVS) can be obtained with the aid of ripple free coupled inductors to the main active switches, and reverse recovery problems of anti‐parallel diodes of the active switches are resolved.…”

GaN-based high efficiency bidirectional DC-DC converter with 10 MHz switching frequency

“…This converter is able to work in Buck, Boost and Buck-Boost modes depending on input and output voltages, therefore can achieve bidirectional operation. At the switching frequency of 10 MHz, the designed converter can achieve 94.4% efficiency, and the power density is 6.25W/cm 3 . A precise dead time control to minimize the conduction loss is important for efficiency improvement.…”

“…Bidirectional DC-DC converters, which can effectively interface energy storage devices such as batteries, supercapacitors and reversible fuel cells to power conversion systems within applications of electrical vehicles (EVs), renewable energy generation (REG), uninterruptible power supplies (USPs) etc., have gained increasing attention in academia and industry over the last decade [1]- [3]. Moreover, with the emergence of applying wide bandgap devices such as Silicon Carbide (SiC) and Gallium Nitride (GaN) based power switches, power electronic converters tend to be even faster, smaller and more efficient, due to the increased electrical field strength and electron mobility compared to than their silicon (Si) based counterparts [4]- [9].…”

Analysis and Controller Design of a Universal Bidirectional DC-DC Converter

“…In [27], sliding mode control is proposed to improve the performance of bidirectional DC-DC converters, the soft switching issue is not addressed since the proposed system utilizes conventional cascade buck/boost structure. In [28], a novel ZVS control technique based on discontinuous conduction mode is proposed. The presented control approach can achieve reliable ZVS within the entire operating range without additional circuits.…”