Design and implementation of an ADC-based real-time simulator along with an optimal selection of the switch model parameters

The method for modeling switching converters plays a key role in real-time simulators. Associate discrete circuit (ADC) modeling technique is a commonly used method for modeling the switching converter. However, the optimal selection of the ADC-based switch model parameters has great importance in the accuracy of the real-time simulator. In this paper, the design of a real-time simulator for a switching power converter has been done, in which a novel method for detecting optimum values of the switch model parameters has been expressed. Particle swarm optimization (PSO) algorithm is used to find these optimum values using state-space analysis of the modeled circuit in the z-domain. The modified nodal analysis (MNA) method solves the real-time model at each simulation time-step. Case studies are a single-phase 5-level Cascaded H-Bridge (CHB), three-phase 9-level CHB inverter, and a Transmission line. Field-programmable gate array (FPGA) has been used as a platform for implementing the real-time simulator. Experimental result of the real-time simulator of the 5-level CHB inverter on a SPARTAN-6 FPGA and its comparison with the result of a prototype of a 5-level CHB inverter confirms not only the performance of the real-time simulator, but also the effectiveness of the proposed method for confirming the real-time simulator accuracy.