Transmission Line Protection Using Dynamic State Estimation and Advanced Sensors: Experimental Validation

Abstract

This paper presents the experimental validation of a protection scheme for a transmission line based on dynamic state estimation along with the practical application of advanced sensors in this protection scheme. The scheme performs dynamic state estimation with high-frequency measurements provided by the sensors, assesses the operating condition (i.e., health) of the transmission line in real-time, and thereby determines the tripping signal whenever a fault is detected. The validation was carried out in two steps, first with simulation studies for a three-phase fault and then with the experimental implementation using a physical scaled-down model of a power system consisting of transmission lines, transformers, and loads. The simulation and validation results have shown that the scheme performs adequately in both normal and fault conditions. In the fault case with the experimental setup, the scheme could correctly detect the fault and send the trip signal to the line's circuit breakers with a total fault clearing time of approximately 65 milliseconds which is comparable to conventional protection methods. The average processing time for a measurement sample block is 12.5 milliseconds. The results demonstrate that this scheme and the sensors would work for transmission line protection which can avoid relay coordination and settings issues.

Dynamic state estimation based transmission line protection scheme: Performance evaluation with different fault types and conditions

“…From a design perspective, any new protection scheme should be able to accurately and timely detect all the different fault types and conditions. In this regard, this paper continues the work presented in [17] by additionally evaluating the performance of DSEBPS in the case of a transmission line with different fault types and conditions, such as single-line-to-ground and double-line-to-ground fault under resistive and inductive load, high impedance fault, fault current fed from both ends, hidden failure, external fault, and load change conditions. Prior to the experimental validation, this work involves the implementation and execution of DSEBPS in simulation and thereafter extensive case studies, which help to set up the requirements of the experimental setup.…”

“…The real-time sampled measurements are received by the smart node (a laptop in this setup) by installing advanced sensors at the transmission line. The configuration details of the laptop used in the setup are presented in [17]. The measurements are processed along with the transmission line dynamic model to perform DSE.…”

“…Our previous work [17] has demonstrated the feasibility of using DSEBPS for transmission line protection by performing the simulations under different fault types and conditions and validation using an experimental setup, consisting of an accurate scaled-down model of a simple power system. The experimental setup also included the interface of circuit breakers, preparation of communication requirements, and the setting up of advanced sensors as an affordable and reliable real-time measurement solution.…”

“…After the preparation of the experimental setup, the DSE algorithm along with the open platform of the advanced sensors was implemented in Python to be employed in carrying out the test and then evaluating the practical feasibility of DSEBPS. However, the work presented in [17] has validated the performance of DSEBPS for a three-phase fault only, while in reality transmission lines are exposed to different types of faults and conditions. From a design perspective, any new protection scheme should be able to accurately and timely detect all the different fault types and conditions.…”