ICERGi is taking part in APEC 2016 with papers on “Implementation of multi-level bridgeless PFC rectifiers for mid-power single phase application” and “Stack multiphase asymmetrical half-bridge topology offering advance performance and efficiency ” presented by Dr. Trong Tue Vu including a poster session on 24th March 2016.
Multi-level approaches to AC/DC power conversion have been successfully deployed in high-voltage high-power industrial applications, and are recently considered for mid-power ranges due to their capability of reducing component sizes and improving efficiency. The main challenge for mid-power deployment is the complexity of sensing circuits and control algorithms used to maintain the capacitor voltage balance, which typically results in expensive and impractical designs. Although several studies have been carried out to address the issue, they have not simplified the system complexity and fully exploited the advantages of multi-level converters. This paper presents a new four-level topology for PFC rectifiers, and demonstrates its performance and practicality through a 200W prototype. The theoretical works and experimental results are also provided to confirm the feasibility of the solution.
In quest of higher efficiency and power density, various studies have been carried out to boost the performance of conventional asymmetrical half bridge (AHB) topologies through either magnetics optimization or deployments of fully soft switching schemes. Although the reporting results from existing works are quite promising, none of them show significant breakthrough in power conversion density which is currently limited by existing technologies for high-voltage (above 500V) MOSFETs. This paper proposes a novel stacked multiphase asymmetrical half bridge (SMAHB) topology operating in a similar manner as conventional AHB converters, but enabling deployment of 250V MOSFETs for faster switching and material reduction in magnetics and EMI filters, which allows high efficient and compact implementation. The operation and performance of the proposed converter is confirmed via both simulated and experimental data.