Research on Grid Planning of Dual Power Distribution Network Based on Parallel Ant Colony Optimization Algorithm

A distribution network plays an extremely important role in the safe and efficient operation of a power grid.As the core part of a power grid’s operation,a distribution network will have a significant impact on the safety and reliability of residential electricity consumption.it is necessary to actively plan and modify the distribution network’s structure in the power grid,improve the quality of the distribution network,and optimize the planning of the distribution network,so that the network can be fully utilized to meet the needs of electricity consumption.In this paper,a distribution network grid planning algorithm based on the reliability of electricity consumption was completed using ant colony algorithm.For the distribution network structure planning of dual power sources,the parallel ant colony algorithm was used to prove that the premise of parallelism is the interactive process of ant colonies,and the dual power distribution network structure model is established based on the principle of the lowest cost.The artificial ants in the algorithm were compared with real ants in nature,and the basic steps and working principle of the ant colony optimization algorithm was studied with the help of the travelling salesman problem(TSP).Then,the limitations of the ant colony algorithm were analyzed,and an improvement strategy was proposed by using python for digital simulation.The results demonstrated the reliability of model-building and algorithm improvement.

Dynamic Power Transmission Using Common RF Feeder with Dual Supply

This paper proposes the design concept of a dynamic charging system for electric vehicles using multiple transmitter coils connected to a common radio frequency(RF)feeder driven by a pair of two power supplies.Using a common RF feeder for multiple transmitter coils reduces the power electronic redundancy compared to a conventional system,where each transmitter coil is individually driven by one switched-mode power supply.Currently,wireless charging of electric vehicles is recommended to operate in the frequency range of 85 kHz and beyond.In this frequency range,the signal wavelength is shorter than about 3.5 km.Therefore,a charging pad longer than several hundred meters is subject to the standing wave effect.In such a case,the voltage significantly varies along the RF feeder,resulting in a variation in the received power level when the receiver moves.Specifically,the received power significantly deteriorates when the receiver is nearby a node of the voltage standing wave.In this paper,we employ a pair of two power sources which are electrically separated by an odd-integer number of the quarter wavelength to drive the RF feeder.As a result,the voltage standing wave generated by one power source is complemented by that of the other,leading to stable received power and transmission efficiency at all the receiver’s positions along with the charging pad.Simulation results at the 85 kHz frequency band verify the output power stabilization effect of the proposed design.It is worth noting that the proposed concept can also be applied to simultaneous wireless information and power transfer(SWIPT)for passive radio frequency identification(RFID)tags by raising the operation frequency to higher industrial,scientific and medical(ISM)bands,e.g.,13.56 MHz and employing similar modulation methods as in the current RFID technology.

Dual Power Allocation Optimization Based on Stackelberg Game in Heterogeneous Network with Hybrid Energy Supplies

In heterogeneous network with hybrid energy supplies including green energy and on-grid energy, it is imperative to increase the utilization of green energy as well as to improve the utilities of users and networks. As the difference of hybrid energy source in stability and economy, thus, this paper focuses on the network with hybrid energy source, and design the utility of each user in the hybrid energy source system from the perspective of stability, economy and environment pollution. A dual power allocation algorithm based on Stackelberg game to maximize the utilities of users and networks is proposed. In addition, an iteration method is proposed which enables all players to reach the Stackelberg equilibrium(SE). Simulation results validate that players can reach the SE and the utilities of users and networks can be maximization, and the green energy can be efficiently used.

Dynamics of a Dual Power-split Transmission Based on Loaded Tooth Contact Analysis

In order to implement the dynamic characteristic of a dual power-split transmission, a dynamic me- chanics model is built. Firstly, according to the method of theoretical analysis of the tooth contact analysis （TCA） and loaded tooth contact analysis （LTCA）, the actual meshing process of each gear pairs is simulated, and the time-varying mesh stiffness excitations are obtained, which can improve the numerical precision. Second- ly, by using the lumped mass method, the bending-torsional coupling three dimensional dynamic model of the dual power-split transmission is established, and the identical dimensionless equations are deduced by elimina- ting the effect of rigid displacement and the method of dimensional normalization. Finally, by the method of the fourth order Runge-Kutta algorithm with variable step lengths, the responses of this system in a frequency domain and time domain are obtained, and the dynamic load change characteristics of each gear pairs are analyzed. The results show that the establishment, solution and analysis of the system dynamics model could provide a basis for the dynamic design, and have an important significance for the dynamic efficiency analysis and dynamic perform- ance optimization design of the dual power-split transmission.

Novel design of a compact tunable dual band wireless power transfer(TDB-WPT)system for multiple WPT applications

In this study we present the design and realization of a tunable dual band wireless power transfer(TDB-WPT)coupled resonator system.The frequency response of the tunable band can be controlled using a surface-mounted varactor.The transmitter(Tx)and the receiver(Rx)circuits are symmetric.The top layer contains a feed line with an impedance of 50Ω.Two identical half rings defected ground structures(HR-DGSs)are loaded on the bottom using a varactor diode.We propose a solution for restricted WPT systems working at a single band application according to the operating frequency.The effects of geometry,orientation,relative distance,and misalignments on the coupling coefficients were studied.To validate the simulation results,the proposed TDB-WPT system was fabricated and tested.The system occupied a space of 40 mm×40 mm.It can deliver power to the receiver with an average coupling efficiency of 98%at the tuned band from 817 to 1018 MHz and an efficiency of 95%at a fixed band of 1.6 GHz at a significant transmission distance of 22 mm.The results of the measurements accorded well with those of an equivalent model and the simulation.

Modification and Optimization of a Baking Oven for Small Scale Bread Production

An existing small-scale single-powered baking oven was modified and optimize into a dual-powered oven. The oven was redesigned to accommodate the initially designed firewood heat source and the newly introduced gas heat source. Four heat exchangers (thermal pipes) were introduced to the baking chamber for effective heat and mass transfer during baking of bread dough. The thermal pipes were made of 2 mm thick hollow galvanized steel pipe of 23 mm diameter and 660 mm length. The performance of the oven was evaluated using the standard performance index, which includes baking capacity, baking efficiency and weight loss of the baked bread. The baked bread’s physical properties were determined and analyzed using Duncan multiple range ANOVA test at significant level of p < 0.05. These properties were optimized to determine the generate regression models using 3D model plot. The baking capacity, baking efficiency, weight loss and optimum baking temperature were: 101.9 kg/h, 46.44% (wood-fired);70.34% (gas-fired), 13.5 g (wood-fired);and 25.5 g (gas-fired), 150˚C, respectively. The physical properties of baked bread, wood-fired were found to correspond with that of gas-fired oven. The modified oven can be used for the baking of dough at domestic, small and medium scale bakery.

On distributed power control in full duplex wireless networks

In this paper, we first consider the problem of distributed power control in a Full Duplex （FD） wireless network consisting of multiple pairs of nodes, within which each node needs to communicate with its corresponding node. We aim to find the optimal transmition power for the FD transmitters such that the network-wide capacity is maximized. Based on the high Signal-to-Interference-Plus-Noise Ratio （SINR） approximation and a more general approximation method for logarithm functions, we develop effective distributed power control algorithms with the dual decomposition approach. We also extend the work to the general FD network scenario, which can be decomposed into subproblems of isolated nodes, paths, and cycles. The corresponding power control problem is then be solved with the distributed algorithm. The proposed algorithms are validated with simulation studies.

Application of CFD-DEM to the study of solid exchange in a dual-leg fluidized bed

The CFD-DEM model was developed to simulate solid exchange behavior between two half beds in a bench-scale two-dimensional dual-leg fluidized bed （DL-FB）. Power spectrum density （PSD） analysis was applied to obtain the dominant frequency （F） of the simulated differential particle number （APLR） between the two half beds. Effects of fluidization velocity （u） and bed material inventory （H） on the solid exchange behavior were studied using the CFD-DEM model. Not only snapshots of the simulated particle flow patterns using the OpenGL code but also the dominant frequency of APLR was similar to the experimental results. The simulation results show that higher fluidization velocity assists the exchange of more particles between the two half beds, but the dispersion of clusters on the bed surface into single particles decreases the cluster exchange frequency. A greater bed material inventory results in more intense cluster exchange. The cluster exchange frequency decreases with an increase of the bed material inventory.