Key techniques in real time digital simulation for closed-loop testing of HVDC systems

This paper introduces several key techniques in realtime digital simulation for closed-loop testing of high voltage direct current (HVDC) systems, including line commutated converter (LCC) HVDC valve group models, modular multilevel converter (MMC) HVDC models, phase domain frequency dependent transmission line models, and switchable filter models. Various issues such as background, algorithms, implementations, applications, and validation of these models are introduced. These techniques represent the most advanced technology in modelling HVDC systems on a real time simulator. The models have been implemented on the RTDS Simulator, a comprehensive real time power system digital simulation tool.