Generic high level VSC-HVDC grid controls and test systems for offline and real time simulation

This article describes generic high level control models for VSC-HVDC grid systems. An average value model of the voltage source converter (VSC) is used; it includes the vector current control strategy. As an improvement to traditional conventional high-level control systems, this paper includes dc voltage, negative sequence current and dc voltage droop control loops. To validate the controller´s performances, two tests systems were developed: a point-to-point link and a four-terminal DC grid. Both offline and real-time simulations are carried out for several test scenarios. A methodology for calibrating controller parameters is presented and used to tune the controls of each test system considering the different scenarios presented. All simulation models were developed in SimPowerSystem/Simulink and prepared using the RT-LAB software from Opal-RT for real-time simulation; real-time simulation performance of the simulation models is also discussed.