Broadband Transmission and Statistical Performance Properties of Overhead High-Voltage Transmission Networks

Abstract

This paper considers broadband signal transmission and statistical performance properties of high-voltage/broadband over power lines (HV/BPL) channels associated with overhead power transmission. The overhead HV/BPL transmission channel is investigated with regard to its spectral behavior, its end-to-end signal attenuation, and its statistical performance metrics. It is found that the above features depend critically on the frequency, the overhead HV power grid type (150 kV, 275 kV, or 400 kV and single-or double-circuit), the coupling scheme applied, the physical properties of the cables used, the MTL configuration, and the type of branches existing along the end-to-end BPL signal propagation. The contribution of this paper is threefold. First, the significant broadband transmission potential of overhead HV lines is revealed. The results demonstrate that, regardless of overhead HV power grid type, the overhead HV grid is a potentially excellent communications medium, offering low-loss characteristics, flat-fading features, and low multipath dispersion over a 25 km repeater span well beyond 100 MHz. Second, regarding the statistical properties of various overhead HV/BPL transmission channels, two fundamental correlations of several wireline systems, for example, coaxial cables and xDSL, are also validated in the case of overhead HV/BPL transmission channels, namely, (i) end-toend channel attenuation in relation with root-mean-square delay spread (RMS-DS) and (ii) coherence bandwidth (CB) in relation with RMS-DS. Third, fitting the numerical results and other field trial measurements, two regression distributions suitable for each fundamental correlation are proposed.

Review and Progress towards the Common Broadband Management of High-Voltage Transmission Grids: Model Expansion and Comparative Modal Analysis

“…Based on [3,36,42,43], in this paper, a top-down approach is proposed to determine the end-to-end attenuation of overhead HV/BPL channels based on an exact version of multidimensional chain scattering matrix or T-Matrix method. This novel extended chain scattering matrix or TMatrix (TM2) method, which is already well verified in the case of overhead and underground LV/BPL and MV/BPL distribution power grids [3], combines the accuracy of the generic multidimensional network analysis tool presented in [3,36,42,43] and the simplicity of hybrid model of [1][2][3][21][22][23][24][25]. Based on numerical results concerning various simulated overhead HV/BPL topologies, BPL transmission via the overhead transmission power grid is investigated aiming at clarifying the influence of factors, such as the overhead HV power grid type (150 kV, 275 kV, or 400 kV and single or double circuit), the physical properties of the cables used, the MTL configuration, the end-to-end distance, and the number, the length, the terminations, and the multiplicity of the branches encountered along the endto-end BPL signal propagation.…”

“…Due to ubiquitous nature of the transmission and distribution power grids, the structure of these grids-that is, low-voltage (LV), medium-voltage (MV), and high-voltage (HV) grids-is the key to developing an IP-based power system, offering a plethora of potential smart grid (SG) applications [1][2][3][4][5]. In the meanwhile, the deployment of broadband over power lines (BPL) networks through the entire transmission and distribution grid forms a potentially convenient and inexpensive communications medium for delivering broadband last mile access in remote and/or underdeveloped areas [6][7][8].…”

“…Since the overhead power grid was not originally designed to serve the purpose of a transmission medium for communication signals, the overhead transmission power grids are subjected to attenuation, multipath due to various reflections, noise, and electromagnetic interference [1][2][3][21][22][23][24][25][26][27][28][29][30][31]. Each of the aforementioned adverse factors affects critically the overall performance and the design of BPL systems [32][33][34][35].…”

“…As usually done in BPL transmission, a hybrid model is employed to examine the behavior of BPL transmission channels installed on BPL multiconductor transmission line (MTL) structures [1,2,[21][22][23][24][25][36][37][38][39][40][41]. Through a bottom-up approach consisting of an appropriate combination of the similarity transformation and MTL theory, the modes that may be supported by an overhead HV/BPL configuration are determined concerning their propagation constants and their characteristic impedances [1-3, 21-25, 35-47].…”

“…Following the first steps towards overhead HV/BPL system integration made in [1,2], a consequence of the proposed top-down modeling and common PHY framework is that their combination further enhances the intraoperability/interoperability of overhead HV/BPL systems in a SG environment.…”