FPGA design methodology for DSP industrial applications - A case study of a three-phase positive-sequence detector

Very important fields for utilization of FPGA technology are industrial applications such as power converters, renewable energy systems, uninterruptible power supplies, active power filters, dynamic voltage restorers and power systems protection. Many of these applications require the detection of three-phase signals characteristics. Generally, these techniques are implemented in DSP devices, with the execution time limited by sample rates of input signals. FPGA implementation results in several advantages. In this paper, an FPGA design flow for industrial digital signal processing is proposed. The first contribution is a metric for comparison between FPGA devices and DSP devices. This metric estimates the quality of implementations based on the efficiency of resources utilization in both technologies. A case study of a magnitude and phase angle detector of the fundamental-frequency positive-sequence component of a three-phase signal is presented. As a second contribution, a proposed FPGA-controller architecture is presented. For validation of the proposed metric, the advantages and possibilities of the use of FPGA in the case study are demonstrated in comparison with the DSP, in terms of the efficiency of resource usage metric, which is based on the capacity for increasing the application algorithms complexity and capacity of exploring the parallelism of operations, allowing for a much shorter execution time.