Control strategy research of LCC based multiterminal HVDC system

Abstract

This paper focuses on the study of the paralleled multi-terminal HVDC system (MTDC). A control strategy is investigated for LCC-MTDC system based on the autonomous decentralized theory. By this approach, a stable operating point can be reached from initial starting independent of communication coordination. Simulation is performed on a model of LCC-MTDC system with four terminals using PSCAD/EMTDC and the results show that the proposed control strategy has satisfactory dynamic characteristics and the LCC-MTDC system can recover and reach a stable operating state after a temporary fault even without communication. This control strategy may contribute to extension of MTDC system, even the development of DC grid.