Practical Coupled Resonators in Domino Arrangements for Power Transmission and Distribution: Replacing Step-Down Power Transformers and Their Branches across the Power Grid

Abstract

This paper considers the potential of replacing step-down power transformers of the entire power grid as well as part of their transmission line branches with wireless power transfer (WPT) technology components. Exploiting the state-of-the-art evolutions in the fields of WPT technology, coupled resonators in domino arrangements—domino coupled resonator (DCR) configurations—are proposed as suitable technological substitute for step-down power transformers and are investigated in terms of performance metrics such as power transfer efficiency (PTE) and transformation ratio (TR). The contribution of this paper is fivefold. First, an analytical theoretical analysis appropriate to the study of practical DCR configurations is demonstrated. In order to support the DCR configuration replacement venture, a detailed set of assumptions regarding efficient mid- and long-range high-power WPTs as well as related technical issues is first presented. The validity of the theoretical analysis is verified through experimental measurements. Second, applying the proposed theoretical analysis, a wealth of system parameters that mainly influences the PTE and TR of DCR configurations is identified. Their quantitative effect as well as corresponding DCR configuration adjustments are first presented. Third, an approximate method, denoted as approximate chain scattering matrix (CSM) method, is first introduced. Based on the scattering matrix theory formalism, the approximate CSM method is suitable for mid- and long-range DCR configurations when the theoretical analysis becomes computationally slow. The numerical results of approximate CSM method are compared with the respective ones of theoretical analysis validating the extent and the accuracy of approximate CSM method. Fourth, the potential of power transformer replacement with practical DCR configurations is thoroughly investigated in terms of their TRs. A plethora of high-voltage/medium-voltage (HV/MV), MV/low-voltage (MV/LV), and HV/LV power transformers used across the world is investigated verifying their replacement potential with practical DCR configurations in all the cases examined. Fifth, based on a detailed collection of dimensions concerning power transformers and transmission line branches, it is first verified that practical DCR configurations cannot only substitute all step-down power transformers of the today's power grid but also replace entire transmission line branches too. Finally, it is obvious that there is a long journey ahead for WPT technology and its ultramodern DCR configurations to be affordably, widely, reliably, sustainably, and safely adopted in the human society. During these first steps of WPT development for power transmission and distribution, theoretical analyses and visions are necessary. The last cable problem, that is, the seamless power delivery as easily as information is now transmitted through the air, is one of the major technological challenges of the 21st century, and, thus, WPT technology will certainly play key role.

Integration of LiFi, BPL, and Fiber Optic Technologies in Smart Grid Backbone Networks: A Proposal for Exploiting the LiFi LED Street Lighting Networks of Power Utilities and Smart Cities

“…Apart from the many times faster LiFi internet connectivity of the passengers, LiFi does not create EMI to aircraft equipment, e.g., the radar, navigational system, other avionics; (ii) Healthcare [22,51]: In many areas of hospitals, e.g., operating rooms, WiFi is not allowed as a precautionary measure against the anticipated EMI either to medical equipment or to the patient's health. [50,56]: Apart from the communications aspect of LiFi, the integration of a thin crystal layer that may act as a solar photovoltaic cell can allow the charging of smart devices and electric vehicles. Therefore, LiFi can provide the communications channel, the illumination and the wireless power transfer for smart devices and electric vehicles, e.g., ad hoc vehicular networks, short-range LiFi systems between smart devices, LiFi drones; (ix) Smart Home [25,57,58]: LiFi technology may keep smartphones, smart televisions and other home devices online without competing for the indoor WiFi bandwidth.…”

“…For the previous reason, LiFi LED street lighting networks are treated as a complementary technology and as a force multiplier to the WiFi networks of the smart cities, while their use is expected to be maximized except for daytime hours. • With reference to application (viii), achieving long battery longevity for the devices of the IoT era is going to require an accumulation of divergent energy harvesting strategies [56,[61][62][63]. Among the major wireless charging techniques (i.e., sunlight, inductive coupling, magnetic resonance, coupling, microwave radiation, distributed laser charging), LiFi LED street lighting configurations may be capable of safely providing power to mobile devices [50,56,61,64].…”

“…• With reference to application (viii), achieving long battery longevity for the devices of the IoT era is going to require an accumulation of divergent energy harvesting strategies [56,[61][62][63]. Among the major wireless charging techniques (i.e., sunlight, inductive coupling, magnetic resonance, coupling, microwave radiation, distributed laser charging), LiFi LED street lighting configurations may be capable of safely providing power to mobile devices [50,56,61,64]. Therefore, LiFi LED street lighting networks under the aegis of power utilities and smart cities can also provide free broadband connectivity and battery charging.…”

Financially Stimulating Local Economies by Exploiting Communities’ Microgrids: Power Trading and Hybrid Techno-Economic (HTE) Model

“…Building smart offices [96], smart hospitals [97], [98] and smart universities [99], [100] is an emerging trend that encompasses Weiser's ubiquitous/pervasive computing concept [101] through the seamless integration of technologies [100]. Finally, the combined operation of community's MGs with other supported communications networks can also significantly improve the economic performance of MGs [102]- [107]. At the same time, the development of new ad-hoc power allocation algorithms and financial trade-off curves for community's MGs at a local and daily basis as well as their fairness and stability when various fluctuations occur in the MG surrounding environment define another two critical community's MG research topics [108]- [114].…”

Design of Asymmetrical Relay Resonators for Maximum Efficiency of Wireless Power Transfer

“…Another approach to improve the power transfer efficiency at long distance is to employ the relay resonators [16][17][18][19][20][21][22][23][24][25][26][27]. Many researches on relay resonators of magnetic resonance WPT have been conducted to extend the distance of power transfer.…”