A Reconfigurable Phase-Shift Full-Bridge Converter for the Wide Output Voltage EV Charging Application

This paper proposes a new phase-shift full-bridge (PSFB) DC/DC converter with a reconfigurable secondary side for the wide output voltage range Electric Vehicle (EV) charging application. This converter features a two-secondary-windings transformer and two auxiliary switches. Its rectifying stage can be configured into a full-bridge rectifier when the output voltage is high or as a center-tapped rectifier when the output voltage is low. As a result, the efficiency of the proposed converter at low output voltage can be significantly improved compared to the conventional PSFB converter, making it suitable for the wide output voltage range EV charging application. This paper presents the steady state analytical modeling of the proposed converter, which is verified by circuit simulations. The loss comparison between the proposed converter and the conventional PSFB converter designed for the EV charging application is presented, and the efficiency improvement is for the proposed converter.</p

A Reconfigurable Two-stage 11kW DC-DC Resonant Converter for EV Charging with a 150-1000V Output Voltage Range

In this paper, a reconfigurable two-stage DC/DC resonant topology with a wide output voltage range of 150-1000V is proposed for Electric Vehicle (EV) charging with high efficiency over the entire load range. The proposed topology consists of an LLC resonant converter with dual secondary sides; two interleaved triangular current mode buck converters, and three additional auxiliary switches for reconfiguration. Two possible arrangements of the proposed topology are considered and compared. The analytical model of the topology is developed, which is used for the efficiency estimation of different configurations and the design of the prototype converter. An 11kW hardware demonstrator is built and tested. The maximum measured efficiency of the converter is 97.66%, with a &gt;95% efficiency over the complete 150-1000V range at full power. The proposed two-stage converter achieves the widest output voltage range reported in literature for resonant power converters, thereby capable of charging existing and future EVs very efficiently over any charging cycle.</p

Dual Active Bridge Converter With Variable Switching Frequency Modulation to Maintain ZVS

A variable switching frequency modulation for the Dual Active Bridge (DAB) converter is proposed in this paper. With this variable switching frequency modulation, the DAB converter can be operated in the ZVS-beneficial operational modes without the necessity to transition to others, thus a larger ZVS range for the DAB converter can be achieved. This modulation has potential of providing higher power efficiency and better EMI performance for the DAB converter in wide voltage range applications such as Electric Vehicle (EV) charging. A DAB converter with the variable frequency modulation method is simulated, and its effectiveness on the ZVS performance is demonstrated.</p

A GaN-based Power Factor Correction Converter: for Electric Vehicle Charging

Because of its superior conduction and switching performance, and falling price, Gallium Nitride (GaN) power semiconductor device is expected to bring improvements to the power electronics system, including higher efficiency and higher power density. How will the new semiconductor device benefit the rapidly growing Electric Vehicle (EV) charging application, where high efficiency, high power density are two of the most important design requirements? In order to verify the match between the new semiconductors and the EV charger application, hardware demonstration needs to be carried out. In this thesis project, the design of a GaN-based, high switching frequency, single phase, 2KW PFC converter for EV charging will be introduced. The operation principle and control of the converter will be explained, and the hardware demonstration results will be shown. The testing results prove the high-efficiency, high-frequency abilities of the new technology

Multi-objective Design and Benchmark of Wide Voltage Range Phase-Shift Full Bridge DC/DC Converters for EV Charging Application

This paper presents an analysis, multi-objective design, and benchmark of three modified Phase-Shift Full-Bridge (PSFB) converters that are well-suited for Electric Vehicle (EV) battery charging applications, covering both typical battery voltage classes (400V and 800V). These three modified PSFB converters, denoted as the t-PSFB, r-PSFB, and i-PSFB converters, have the ability to reconfigure and provide better efficiency performance in the wide voltage range necessary for public EV battery charging applications. In this paper, the characteristics and design considerations of these reconfigurable PSFB converters are discussed in detail. A multi-objective converter design process is proposed to optimize the average efficiency, normalized cost, and power density of the magnetic components and heat sinks. This design process employs the correlations between the cost and performance indexes of the key components derived based on open and accessible components data to estimate the design objectives. In this way, the design process is not constrained by certain component choices, making it easier to identify the most advantageous design. A benchmark study is conducted among the re-configurable PSFB topologies and the conventional PSFB circuit using the proposed multi-objective design process. To validate the analysis, a close-to-Pareto-front 11kW, 45kHz r-PSFB converter prototype with 640-840V input voltage and 250-1000V output voltage ranges is developed and tested