Improved Dynamic State Estimation Based Protection on VSC-HVDC Transmission Lines with Full Exploitation of Information Redundancy

To ensure quick and reliable primary protection on VSCHVDC transmission lines, this paper proposes an improved Dynamic State Estimation (DSE) based protection method with full exploitation of information redundancy. The proposed approach improves the existing DSE based protection method by establishing a new dynamic model of the line under protection, which considers information redundancy embedded in the protection problem. The new dynamic model is systematically solved through the DSE procedure with weight matrices that are mathematically derived. Numerical experiments in an example VSC-HVDC system validate that the proposed DSE based protection method has improved selectivity, dependability and security compared to the existing DSE based protection method. In addition, the computation burden of the method is also carefully examined to ensure that it can meet real-time operation requirements of protective relays in practice.