A Flexible DSP-FPGA Based Platform for Experiments with Modular Multilevel Cascade Converters

Abstract


 The growing use of Modular Multilevel Cascade Converter (MMCC) topologies in applications such as High Voltage Direct Current Transmission, Static Var Compensation, Alternating Current (AC) Drives and renewable energy systems, among others, turns their study relevant. However, as the number of Power Submodules in the MMCCs increases, the applied control strategies, data communication and digital hardware complexity increases as well. This paper proposes a flexible and scalable platform, that is adequate for implementing different MMCC topologies (single star, single delta or double star), communication schemes (star or ring) and control strategies (centralized or distributed). The Processing Board explores the availability of Field Programmable Gate Arrays, Digital Signal Processors and ARM microcontrollers. The Power and Measurement Submodules processing capability is provided by Complex Programmable Logic Devices and ARM microcontrollers. Description of the tasks implemented in the processing devices and experiments are presented for a test case, in which a double star topology with star communication and centralized processing strategy is tested using fixed switching frequency and equally displaced carriers.