| Abstract |
Current source modular multilevel converters (CSMMCs) in high-power applications can consist of largenumber of submodules. Simulations of such systems using full-size traditional detailed model in electromagnetic transient-type (EMT-type) simulation tools involve computational complexity and require verylarge computing time. This paper presents a computationally efficient and accurate average-value model(AVM) of CSMMC. In the proposed approach, the individual arm of CSMMC is represented by a controlledcurrent source and the dc-side of the converter is represented by the controlled voltage sources.The submodule inductances are represented by a single equivalent inductance on the dc-side. The harmoniccontents of the switching events are included using the modulation function in the arm level modelwhile the variations in the submodule inductor currents are ignored. To validate the proposed model, detailedsimulation studies of CSMMC based STATCOM is carried out with the proposed AVM and thetraditional model in PSCAD/EMTDC. The results of various studies, obtained from both the models,are compared. The close matching of the results proves the validity of the proposed AVM. Moreover,the comparison of simulation time of both the models clearly demonstrates very high computationalefficiency of the proposed AVM. |
