A Methodology for Estimating Frequency Responses of Electric Power Grids

Currently, there is a lack of standard methodology to characterize frequency responses of electric power grids for power line communication purpose. As a result, fair comparisons among measurement campaigns carried out in different parts of the world are missing. Aiming at to deal with this issue, this contribution discusses a complete sounding-based methodology to estimate frequency responses of electric power grids combining sampling frequency offset error estimation and correction, timing synchronization, channel estimation, and channel estimation enhancement techniques. The effectiveness of this methodology is validated by using well-known power line channel models, as well as measured ones, covering the frequency band from 1.7 up to 50 MHz. The attained results show that the methodology provides estimates in shorten period of time in comparison with the network analyzer based methodology and because of that it is capable of characterizing the periodically and time-varying behavior of electric power grids. Additionally, it is shown that the methodology can be successfully applied to characterize frequency responses of electric equipment and, as a consequence, it is very useful for both power line communication and power system applications.