Power quality is one of many issues affecting the traction power supply system. Prominent among the causes of poor power quality is voltage low-frequency oscillation (VLFO). In this paper, a fuzzy-based PI (FPI) controller to optimize the performance of the traction line-side converter (TLSC) and suppress the effect of VLFO is proposed. Firstly, the mathematical model of China’s railway high-speed five single-phase TLSC is developed, and then the FPI control unit is designed based on specific requirements. The fuzzy antecedent and consequence rules were generated based on the expert and previous knowledge of TLSC operation. An offline simulation of the proposed control scheme under different loads and parameters is conducted to verify the designed. To validate the model, the traction power supply system (TPS) is built on the field-programmable gate array (FPGA) real-time digital simulator (FPGA-RTDS), while the FPI control algorithm is load on modeling tech rapid control prototyping (RCP) real-time digital controller (RTDC). Hardware-in-the-loop (HIL), and offline simulation studies between current decoupling (PI) control, sliding mode control (SMC), and the proposed control method confirms in addition to excellent dynamic performance; the proposed method can successfully suppress the effect of VLFO.
Real-time test-bed system development using power hardware-in-the-loop (PHIL) simulation technique for reliability test of DC nano grid