A state estimation approach for fault location in transmission lines considering data acquisition errors and non-synchronized records

• In this work a state estimation approach is used to determine the fault distance.
• Measurement and digitization errors are being modeled in the estimation process.
• A region of probable fault occurrence is delimited with 95% of success probability.
• The methodology was tested successfully for simulated and real transmission lines.

The performance of algorithms for fault location is directly related to the accuracy of its input data. Thus, factors such as errors in the line parameters, failures in synchronization of oscillographic records and errors in measurements of voltage and current can significantly influence the accuracy of algorithms that use bad data to indicate the faults location. This paper presents a methodology for fault location based on the theory of state estimation in order to determine the location of faults more accurately by considering realistic systematic errors that may be present in measurements of voltage and current. The methodology developed is innovative because, besides calculating the most likely fault distance obtained from measurement errors, the variance associated with the distance found is also determined, using the errors theory. The obtained results are relevant to show that the proposed estimation approach works even adopting realistic variances. Moreover, the fault location brings performance gains compared to a traditional algorithm, available in the literature.