Antonio Coccia

Practical Design and Implementation Procedure of an Interleaved Boost Converter Using SiC Diodes for PV Applications

The implementation of an interleaved boost converter (IBC) using SiC diodes for photovoltaic (PV) applications is presented in this paper. The converter consists of two switching cells sharing the PV panel output current. Their switching patterns are synchronized with 180° phase shift. Each switching cell has a SiC Schottky diode and a CoolMOS switching device. The SiC diodes provide zero reverse-recovery current ideally, which reduces the commutation losses of the switches. Such an advantage from the SiC diodes enables higher efficiency and higher power density of the converter system by reducing the requirement of the cooling system. This paper presents also an optimization study of the size and efficiency of the IBC. Based on 1) the steady-state characteristic of the topology; 2) the static and dynamic characteristics of the switching cells; 3) the loss model of the magnetic components; and 4) the cooling system design, the paper provides a set of design criteria, procedures, and experimental results for a 2.5 kW IBC prototype using SiC diodes.

A Circuit-Level Analytical Study on Switching Behaviors of SiC Diode at Basic Cell for Power Converters

This paper presents a strategy for the analytic determination of the dynamic switching behaviors of the SiC Diode- Si MOSFET basic cell. The approach employs the semiconductor device electrical parameters from data sheets and static characteristic measurements and testing conditions to determine the behaviors of the basic cell. The presented equations can explain the phenomenon of basic cell such as SiC Diode negative current overshoot. A detailed analysis of the typical waveforms during switching is presented stage by stage. Furthermore, a 400V, 4A test bench has been built and tested under different testing conditions in order to determine the main effects. There is good agreement between theoretical analysis and experimental results.

Wide input voltage range compensation in DC/DC resonant architectures for on-board traction power supplies

Several methods to reduce the effect of wide input voltage variation in soft-switched DC/DC converters for high-power and high-voltage traction applications are presented in this paper. To enhance high conversion efficiency together with high reliability and cost reduction, the document addresses the use of a power architecture whose front-end is a three-level half-bridge converter non standard NPC configuration. Thanks to a structured control methodology based on the possibility to use either a two-level or a three-level modulation strategy according to the input voltage level, it is possible to optimize the converter performance over the whole input voltage range. First, the soft-switching implementation of the converter which allows ZVS operation in the entire load range by using the magnetizing inductance of the transformer is discussed. Then, the operation of the converter at both two-level and three-level operation is addressed. Concluding, experimental results obtained in the specified input voltage range are presented to confirm the validity of the theoretical analysis.

Performance evaluation of full SiC switching cell in an interleaved boost converter for PV applications

The paper presents device characteristics of a recent developed 1.2kV silicon carbide (SiC) switching cell and system performance of an interleaved boost converter using that switching cell. The static and dynamic characteristics of the full SiC switching cell, including a SiC MOSFET and a SiC diode, are experimentally extracted and the advantages of the devices are evaluated. A 2.5kW interleaved boost converter for PV applications is implemented as benchmark test system. It is used to evaluate the system efficiency improvement by using the full SiC switching cell. The experimental results show that the SiC MOSFET greatly improves the efficiency of the converter in contrast to Si 1.2kV IGBT devices.

A Novel DC/DC Converter Resonant Architecture for Traction Power Supplies

Abstract A novel method to reduce the effect of wide input voltage variation in soft-switched DC/DC converters for high-power and high-voltage traction applications is presented in this paper. To enhance high conversion efficiency together with high reliability and cost reduction, the document addresses the use of a power architecture whose front-end is a three-level half-bridge converter in differential configuration. Thanks to a structured control methodology based on the possibility to use either a two-level or a three-level modulation strategy according to the input voltage level, it is possible to optimize the converter performance over the whole input voltage range. First, the soft-switching implementation of the converter which allows ZVS (Zero Voltage Switching) operation in the entire load range by using the magnetizing inductance of the transformer is discussed. Then, the operation of the converter at both two-level and three-level operation is addressed. Concluding, experimental results obtained in the specified input voltage range are presented to confirm the validity of the theoretical analysis.