Managing the Complexity of FPGA-Based Rapid Control Prototyping

Siemens Healthineers is exploring rapid control prototyping (RCP) for the development of power electronic components. RCP with FPGAs represents one of the most powerful workflows within the Simulink^® framework. The workflow enables engineers to implement sophisticated and high-performing control systems with very fast design iterations. The tight integration between HDL Coder™ and Simulink Real-Time™ eliminates a lot of intricacies of FPGA design. Nevertheless, FPGA-based RCP remains one of the most complex Simulink workflows. Thus, managing the workflow complexity is one of the key factors for success. Three main topics can be employed to this end: workflow automation, a suitable model architecture, and a well-customized utility library for handling direct memory access (DMA). Developing an FPGA-based RCP application requires many iterations of successive builds with FPGA synthesis, which require approximately one hour each. It is highly recommended to automate this workflow with a continuous integration server to separate this procedure from the core modeling tasks. There are a number of considerations for an effective and sustainable RCP architecture. There needs to be a clear separation between the core responsibilities of experiment design, hardware interfacing, physical modeling, control design, and real-time signal tracing. To be effective, this architecture requires barrier-free communication between CPU and FPGA. Basic support for this comes with the DMA-blocks from Simulink Real-Time. To be really barrier-free and flexible, a DMA utility library has been designed. This presentation encourages the user to think about efficient modeling procedures, the robustness of their designs, and the validity of their model architecture.