Modelling of the 500 MW Back-to-Back Converter Station between Uruguay and Brazil in ATP

Abstract

In order to interconnect the power systems of Uruguay and Brazil with different frequencies, a new 500 MW HVDC back-to-back (HVDC BtB) frequency converter station was built. A complete model of this HVDC BtB has been developed by the authors with ATP (Alternative Transients Program) for conducting power system electromagnetic transient (EMT) simulations. In relation to the work carried out, this paper presents the following issues: the main technical characteristics of the HVDC BtB, the Static Characteristic under normal and abnormal operating conditions and control loops associated, bridge converter and thyristor firing scheme modelling, power converter transformers modelling, temporary over/under voltage control, initialization of the back-to-back model, application and removal of balanced three-phase fault at both rectifier and inverter sides, single phase fault with successful auto-reclosure at Uruguay side. In order to evaluate the ATP model the simulation results were compared against PSCAD and RTDS results given by the manufacturer.