Real-time FPGA-based Hardware-in-the-Loop development test-bench for multiple output power converters

The implementation of multiple-inductor power converters requires often the development of specific purpose control architectures to obtain the most of the converter. These are usually based on a processor, which provides software flexibility, and specific purpose hardware, which provides customized functionalities. In addition, recent trends suggest the integration of both functionalities in a single chip using an embedded processor and customized hardware, providing a System-on-Programmable-Chip (SoPC) solution. The aim of this paper is to implement a SoPC system which provides flexibility and customized hardware, and develop a real-time FPGA-based development test-bench based on the Hardware-In-the-Loop (HIL) simulation technique, which accelerates simulation, reduces design cycle times, and allows software and power converter modulation schemes development. The complete system is integrated by a multiple-inductor power converter and an FPGA, which contains a MicroBlaze embedded processor and a specific purpose Digital Pulse Width Modulator (DPWM). HIL at power level is applied by implementing the power converter model into the FPGA. It has been designed with the VHDL-2008 float_pkg package, which allows a straight-forward implementation. As a result, the digital and the analog power converter signals can be traced by means of ChipScope tool, and the processor software can be traced by means of a software debugger tool.