An EMTP simulation of the HVDC power system of a fusion energy machine

In order to predict the effects of a fusion energy project´s magnet current requirements on the harmonics and power factor at the power system´s supply line source, a detailed three-phase converter model, including the overlap angle, is presented. This converter model is contained within the transient analysis control systems (TACS) portion of the electromagnetic transients program (EMTP). Using TACS variables to control the firing of the individual thyristors, an average load current can be requested, and the delay angle is internally compensated to produce the desired result. Load currents of various durations and amplitudes can be requested. Such a model allows the user to carry out realistic computer studies of typical high-voltage DC systems. The converter representation is then incorporated into an overall EMTP system model. Block diagrams of the converter model are provided. Simulation results utilizing the computer model compare favorably with theoretical expectations and with data resulting from previous fusion energy experiments.<>