Weak Grid Reactive Power Improvement and Voltage Control of MT-HVDC Grid using APF

Abstract

In the present era, attention towards renewable energy resources has been growing due to the ever-growing energy demand and dwindling of fossil fuel reserves. In order to overcome these challenges, offshore energy resources and oil or gas resources integrated with AC power grid is getting popularity and multi-terminal HVDC would be the more feasible solution for long-distance electricity transmission. In this paper, a three-terminal grid-connected MT-HVDC grid is proposed in PSCAD/EMTDC software-based simulation using conventional PQ control and its improved strategy using harmonic elimination while considering weak and stiff grids. By using this technique, the dynamic stability of the grid will be achieved. MT-HVDC is connected through the radial configuration of DC cable. During DC side contingencies, the control structure of voltage source converter (VSC) shows a remarkable part to shape the fault current of MTDC. These results will contribute to addressing future challenges regarding MT-HVDC smart grid.