Conventional Bidirectional Converter Research Articles

Phase-Locked Bidirectional Converter With Pulse Charge Function for 42-V/14-V Dual-Voltage PowerNet

In this paper, a phase-locked bidirectional converter (BC) (PLBC) with pulse charge function is proposed to improve the battery charge efficiency. The circuit topology of the proposed PLBC is the same as that of the current-pump phase-locked loop (CP-PLL). Using CP-PLL inherent characteristics, a pulse current with bidirectional flow can be automatically implemented. A design example for a 42-V/14-V dual-voltage PowerNet is built to assess the PLBC's performance. Compared with the conventional BC, the battery charge efficiency η <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">b</i> is improved by about 2.8%. Moreover, the battery increased temperature is reduced by about 5.7 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> C simultaneously.

Three-Phase Multilevel PWM Rectifiers Based on Conventional Bidirectional Converters

Almost two decades of research on unidirectional three-phase multilevel boost-type pulsewidth modulation (PWM) rectifiers have shown the benefits of employing this technology to comply with power quality standards while assuring high efficiency and low volume and weight. However, the unidirectional topologies directly derived from the conventional three-level bidirectional converters, such as the neutral point clamped (NPC), the flying capacitor and the cascaded H-bridge converters have not been properly analyzed. This letter introduces some of the unidirectional topologies that arise from the inspection of the widespread conventional bidirectional converters. Special emphasis is put in the analysis of the NPC-based three-phase/-level PWM rectifier operating as power factor corrector.

High-Efficiency Bidirectional Converter for Power Sources With Great Voltage Diversity

This study focuses on the development of a high-efficiency bidirectional converter for power sources with large voltage diversity. In conventional bidirectional converters, transformer-based circuit topologies are commonly employed and soft-switching techniques including zero-voltage-switching (ZVS) or zero-current-switching (ZCS) are frequently applied to mitigate corresponding switching losses. Unfortunately, switches of four and upward in these transformer-based schemes increase production costs and reduce conversion efficiency. In this study, a coupled-inductor bidirectional converter scheme utilizes only three power switches to fulfill the objective of bidirectional current control. The high step-up and step-down ratios enable a battery module with a low voltage to be injected into a high-voltage dc bus for subsequent utilization. Some experimental results are given to verify the effectiveness of the proposed bidirectional converter. Since the techniques of voltage clamping, synchronous rectification and soft switching are exploited in this circuit topology, and the corresponding device specifications are adequately fulfilled, it can provide high-efficiency bidirectional power conversion for power sources with large voltage diversity.

A New High Efficient Bi-directional DC/DC Converter in the Dual Voltage System

This paper introduces a new high efficient bi-directional, non-isolated DC/DC converter. Through variations of the topology of the conventional Cuk converter, an optimum bi-directional DC/DC converter is proposed. Voltage and current in the proposed DC/DC converter are continuous. Furthermore, the efficiency in both step-up and step-down mode is improved over that of the conventional bi-directional converter. To prove the validation for the proposed converter, simulations and experiments are executed with a 300W bi-directional converter.