Energy Transmission System Research Articles

Research on Radio Energy Transmission System Based on Parity-Time Symmetry

Magnetically coupled resonant WPT technology can realize long-distance power transmission, which is currently a research hotspot. However, in practical applications, the position between the receiving and transmitting coils is not fixed, and its transmission power and efficiency are greatly affected by the coupling coefficient, which hinders the application and promotion of magnetic coupling resonance technology. To solve this problem, this paper proposes a magnetically coupled resonant radio energy transmission system based on parity time symmetry, designs the system structure, analyzes and explains its working principle and characteristics in detail, and finally verifies the practicability and rationality of the system through simulation analysis.

Research on Wireless Energy Transmission Systems of Coupled Nonlinear Resonator

Due to environmental interference, device aging, and the strict requirements for the relative position of the transceiver coil during charging, we always hope that the output voltage and power can remain stable when the transmission distance of the transmitting and receiving coils changes in the largest range possible. However, once the relative position of the transceiver coil of the traditional linear magnetic coupling resonance WPT system changes, that is, when the transmission distance is not optimal, the transmission performance of the system will be seriously degraded. In practical applications, the charging equipment inevitably moves, and the harsh transmission conditions limit the wide application of WPT technology. To solve this problem, based on the nonlinear characteristics presented by the nonlinear Duffing resonance model, this paper proposes to use a reverse series varactor at the receiving end by adjusting the reverse bias voltage of the varactor. This method compensates for the transmission performance attenuation caused by the change of the coupling coefficient of the transceiver coil to maintain a high level of transmission performance when the relative distance between the transceiver coils is as large as possible.

Spatial Azimuthal Misalignment Characteristics of High-Temperature Superconducting Wireless Power Transmission Systems

Magnetically coupled resonant wireless power transmission technology (WPT) based on high-temperature superconducting (HTS) coils has gained wide popularity due to its low impedance and high-quality factor Q value characteristics. This technology has greatly improved the energy transfer performance of wireless power transmission (WPT) systems. However, practical applications of conventional WPT, such as wireless charging of autonomous underwater vehicles at mooring points, often encounter spatial misalignment issues due to the complex ocean environment and ocean currents. Nonetheless, few studies have investigated the spatial misalignment of HTS WPT systems, particularly the angular misalignment. This paper presents a solution to address this problem by constructing magnetically coupled resonant wireless energy transmission systems based on HTS coils and copper coils. The study analyzes the relationship between the transmission efficiency of the WPT system and the received power of the load with respect to the spatial orientation of the coil. The performance of the superconducting coil and copper coil WPT systems is compared. The experimental results demonstrate that, under the same spatially misaligned conditions, the WPT system using HTS coils can significantly improve the transmission efficiency and load power compared to the conventional copper WPT system. Moreover, simultaneous adjustment of the lateral misalignment distance and different orientation deflection angles can improve the transmission efficiency and smooth load output power of the high-temperature superconducting WPT system.

Optimization methods for planning in electric power grids

A rise in the rate of population growth leads to higher demand rates for electric power consumption. Therefore, it is necessary that the electrical energy generation, transmission and distribution system be planned in an optimized way, in order to provide an excellent service to the consumer and reduce costs for the supply of electrical energy distribution and transmission. For this, the location and load balancing of each substation is extremely important in the distribution systems. The problem can be modeled as a combinatorial optimization problem. In this paper, we propose an allocation model using the p-median for this problem. The heuristic methods developed, to solve this problem, were based on algorithms from Teitz and Bart (1968), to find the best location of the substations, and Gillett and Jhonson (1976), which it designates demand points to be connected to each substation. Finally, an exact method using the branch-and-bound algorithm was used to compare the computational results. The tests used several scenarios applied to the electrical energy distribution networks in a metropolitan region. The computational results were promising in terms of quality as well as in computational time. Finally, the validated algorithm were applied in a database for planning the transmission sector.

Energization of Outer Membrane Transport by the ExbB ExbD Molecular Motor.

The outer membranes (OM) of Gram-negative bacteria contain a class of proteins (TBDTs) that require energy for the import of nutrients and to serve as receptors for phages and protein toxins. Energy is derived from the proton motif force (pmf) of the cytoplasmic membrane (CM) through the action of three proteins, namely, TonB, ExbB, and ExbD, which are located in the CM and extend into the periplasm. The leaky phenotype of exbB exbD mutants is caused by partial complementation by homologous tolQ tolR. TonB, ExbB, and ExbD are genuine components of an energy transmission system from the CM into the OM. Mutant analyses, cross-linking experiments, and most recently X-ray and cryo-EM determinations were undertaken to arrive at a model that describes the energy transfer from the CM into the OM. These results are discussed in this paper. ExbB forms a pentamer with a pore inside, in which an ExbD dimer resides. This complex harvests the energy of the pmf and transmits it to TonB. TonB interacts with the TBDT at the TonB box, which triggers a conformational change in the TBDT that releases bound nutrients and opens the pore, through which nutrients pass into the periplasm. The structurally altered TBDT also changes the interactions of its periplasmic signaling domain with anti-sigma factors, with the consequence being that the sigma factors initiate transcription.

An Efficiency Optimization Strategy for Electric Vehicle Wireless Energy Transmission System

Magnetic coupling resonant wireless energy transmission technology has become an important research direction for electric vehicle wireless charging systems. This paper proposes an efficiency optimization strategy for the electric vehicle wireless energy transmission system based on LCL-S topology to improve the efficiency of electric vehicle magnetic coupling resonant wireless charging. This paper analyzes the optimization method of system efficiency based on LCL-S topology, establishes an experimental model in MATLAB/Simulink simulation software, and verifies it with the control variable method. The experiment shows that the efficiency optimization strategy based on the LCL-S topology proposed in this paper can effectively improve the system transmission efficiency and stabilize the transmission efficiency at a higher level faster.

Experimental Analyses of EMI Noise Separator for CISPR25

In energy transmission systems, devices must be able to work safely with each other. Therefore, electromagnetic emission and susceptibility of the converting systems are expected to be in a certain range. electromagnetic propagation, especially by radiation and conduction, cannot be neglected in power electronics such as electric vehicle, microgrid, aerospace technologies. In order to examine and reduce the noise emitted by the devices, the noise should be separated into common mode and difference mode components. In this study, Shou Wang modeling, which is used to separate the noise components into related components, has been examined in order to analyze the noise components within the framework of the CISPR25 standard used for electric vehicles and redesigned. Circuit simulation and design were done and the results were compared. Thanks to these results, it has been seen that the circuit works efficiently up to 90MHz and gives 8dB S11 reflection parameter at the 108MHz threshold level. In addition, the separator circuit was used in a bidirectional DC-DC converter with a known EMI level of 1KW and the noise components obtained were compared with the components of the converter. As a result, it has been seen that the results obtained using the noise separator circuit are almost the same as the real results. In the 18 - 42 MHz range, only the results obtained with the noise separator are up to 8dBuV higher than the real results, other than that the results are exactly the same.

Polarization-Independent Dual-Band Metasurface Absorber for Wireless Power Transmission

A new design of a polarization-independent dual-band metasurface absorber based on an improved Minkowski fractal structure is proposed in this paper. It is designed for wireless power transmission. The proposed metasurface absorber is composed of many sub-wavelength elements. By adjusting the structure of the elements, it has rotational symmetry and multi-frequency resonance characteristics. The proposed metasurface absorber array can keep more than 87% harvested efficiency at 2.45GHz and 93% harvested efficiency at 5.8GHz for arbitrary polarization of incident electromagnetic waves. The working frequency of the proposed absorber can cover the main working frequency bands of the current microwave wireless energy transmission system. The proposed metasurface absorber, which has the great advantage of subwavelength, polarization-independent, and high harvested efficiency, is suitable for wireless power transmission, especially in ambient power harvesting and UAV remote power supply.

D-q Small-Signal Model for Grid-Forming MMC and Its Application in Electromagnetic-Transient Simulations

The modular multilevel converter (MMC) is a keystone of modern energy transmission systems. Consequently, there is an ongoing pursue for mathematical models to represent it under different configurations and control approaches. In short, this paper introduces an analytical Thévenin-equivalent model for representing the MMC when it is controlled with inner current- and an outer voltage-loop altogether. The model is based on a linearized representation of the converter and conveys the dynamics of passive components, such as submodule capacitors and arm reactors, as well as both control loops. Besides that, the proposed model is divided into a close-loop transfer matrix and the equivalent impedance matrix, both of which represent the relationships between the ac-side dq voltages and currents. We also propose a framework for implementing electromagnetic–transient simulations using the impedance model of this power electronic converter. The framework reduces a multi-bus power grid to a multi-input multi-output (MIMO) feedback system where impedance/admittance matrices of the MMC and other grid elements compose its loops. For validation purposes, it is considered a three-bus power grid comprising one MMC and another two grid-connected VSC. The proposed model was validated by comparing its results with a switching-level PSCAD model of the system.

A high-efficient piezoelectric wireless energy transmission system based on magnetic force coupling.

This research reports an acoustic wireless energy transmission system featuring high efficiency and robustness. The proposed energy transmission system is composed of a piezoelectric cantilever-based transmitter and receiver that are coupled using the forces of permanent magnets. Taking advantage of the strong coupling effect of magnet force, we can transfer mechanical energy wirelessly through mediums of the air and metal plate. The experimental studies show that the voltage transmission efficiencies reach 55.59% and 51.58% in cases of energy transfer through mediums of the air and the air-metal-air, respectively. In addition, the maximum power transmission reaches 42.73 mW at an operational frequency of 104.2Hz. This wireless energy transmission system can be used for powering devices in enclosed, electrically shielded, and biomedical areas.

Multi-objective optimization of parameters for magnetically coupled resonant wireless energy transmission systems

To improve the transmission efficiency and output power of a magnetically coupled resonant wireless energy transmission system, this paper proposes a multi-objective optimization method based on the analytical expression and the improved NSGA-II algorithm. First, the analytical expressions of the electrical and performance parameters in the magnetically coupled resonant mechanism are derived. On this basis, the mathematical model of the multi-objective optimization of the magnetically coupled mechanism is established, with the size, many turns, and wire diameter of the transmitting and receiving coils in the magnetically coupled mechanism as design variables; the resonant frequency of the system, the distance between the coils, and the load size as constraints; and the transmission efficiency and transmission power as optimization objectives. Then the mathematical model is solved by the improved NSGA-II algorithm to obtain the Pareto optimal solution. Finally, the physical system is built to verify the correctness of the simulation experiment and the reliability of the experiment. This study is instructive for optimizing the transmission efficiency and output power of a magnetically coupled resonant wireless energy transmission system.

Multi-Objective optimization method for bus splitting problem in energy transmission system

Multi-Objective optimization method for bus splitting problem in energy transmission system

Multi-Objective optimization method for bus splitting problem in energy transmission system

Multi-Objective optimization method for bus splitting problem in energy transmission system

Long-Term Solar Irradiance Forecasting Using Multilinear Predictors

As the demand for crude oil is increasing every day, prices and pollution are both increasing in return, which has harmful effects on the environment. Thus, more attempts are being made to develop clean energy to rescue the planet and provide humanity with a cleaner energy source. As the renewable energy sector grows, new issues and challenges have emerged. Instability in electricity production from wind turbines, solar power plants, and dams creates challenges for energy transmission and storage systems. In order to achieve a more reliable and effective energy system, machine learning techniques have been used to forecast energy changes. Predicting the sun's Global Horizontal Irradiance (GHI) is one of the machine learning applications used in that sector. In this paper, many machine learning methods have been utilized, such as linear regression and long-short term memory (LSTM) methods to have long term GHI forecasting. Moreover, the significance of this paper is located in the way of prediction of the GHI irradiance prediction by using different levels of the linear regressors to find the best regressor level that provides the minimum error for the testing set based on cross-validation. Results showed that the regressor method provides a lower error compared with a single vanilla LSTM system for a shorter time computationally.

Applications of negative permeability metamaterials for electromagnetic resonance type wireless power transfer systems

With the development of electric drive systems such as unmanned aerial vehicles and electric vehicles, the charging problem of power supply devices has become increasingly prominent. However, the traditional charging method requires physical circuits, which makes it impossible to achieve freedom of the position in actual use. The wireless power transmission technology, which mainly relies on electromagnetic wave to complete energy transmission, is expected to get rid of the restriction of physical space location and solve the problem of charging location, which has great potential in medical treatment, rescue, detection and other fields. However, the low transmission efficiency and short transmission distance caused by electromagnetic field leakage are the two main problems faced by radio energy transmission systems. In general, with the increase of transmission distance, the transmission efficiency will drop sharply. Fortunately, inserting a negative permeability metamaterial with extraordinary electromagnetic characteristics into the transmitting and receiving coils will greatly alleviate this attenuation trend and can also shield electromagnetic radiation to a certain extent. In this paper, some experiments of negative permeability metamaterials used in electromagnetic resonance type wireless power transfer systems are summarized for reference.

Fundamental Study on Improvement of Transmission Efficiency by Applying α-Coil to Transcutaneous Energy Transmission System

Fundamental Study on Improvement of Transmission Efficiency by Applying α-Coil to Transcutaneous Energy Transmission System

Simulation and Design of Wireless Energy Transmission System Based on Visible Light

Simulation and Design of Wireless Energy Transmission System Based on Visible Light

Dual LCL resonance compensation for the design of electric vehicle wireless energy transmission system topology

Dual LCL resonance compensation for the design of electric vehicle wireless energy transmission system topology

An Optimal Parameterized Fractional-Order PID Controller for the Single Phase Grid Integrated with Solar and Wind System

The hybrid solar/wind power systems are the best renewable energy sources because of their complementary nature. The generation of electricity from wind and solar photovoltaic (PV) systems is greatly reliant on the weather. Their intermittent nature causes output fluctuations. As a result, the need for rapid compensation for energy transmission and distribution systems is becoming increasingly critical. In this article, an optimal parameterized Fractional Order Proportional Integral Derivative (FOPID) controller for a hybrid renewable energy system integrated with a single-phase grid. An amalgamation of solar PV and wind is presented as a way to provide continuous power from alternate sources. Furthermore, it is planned to design a robust output voltage management system that utilizes a FOPID controller for the output voltage regulation of the hybrid system integrated with the grid. A novel Randomly Updated Path Finder Algorithm (RU-PF) is proposed to optimize the FOPID gains. Hence, the proposed FOPID-based control for the single-phase grid connected to PV and wind system is simulated in MATLAB/Simulink, and their performance is examined. In particular, the fitness of the proposed RU-PF algorithm is 5.06%, 1.32%, 7.41%, and 0.88% superior to the extant PSO, FF, WOA, and PFA algorithms at the 25th iteration.

Energy Acquisition Through Wireless Power Transfer

Battery-powered devices face unprecedented technical problems due to limits such as low power density, expensive, and heaviness. Wireless power transfer (WPT) is a revolutionary energization pattern that provides a completely new way for electric-driven devices to acquire energy, reducing their reliance on batteries. This study provides a review of WPT approaches, focusing on their working mechanisms, technical obstacles and traditional applications. This study focuses on WPT systems and highlights current important research areas as well as potential development trends. This unique energy transmission system has important implications for the widespread use of renewable energy in our daily lives.