Single measurement based mechanical state estimation for overhead transmission lines with level spans

The electrical and mechanical parameters of the overhead transmission lines are assumed to remain constant as per the design, owing to the unavailability of any online information about them. However, for applications such as power flow analysis, security and reliability assessment, etc. information about these transmission line parameters is essential. This paper proposes a single online tension measurement based mechanical state estimator to estimate the mechanical parameters of OTLs. The estimator utilizes the information of the conductor temperature and the tension measurements at both the ends of the transmission line to estimate their physical states. Thus, it notifies about the physical states of the transmission system with following advantages of Reduction in the amount of data requirement for parameter estimation. Also, it makes the problem equivalent to solving a minimization problem. The proposed estimator is tested on available data set. Results show accurate estimate of the mechanical sag by the proposed estimator.