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The establishment of an integrated charging station with PV, energy storage and battery swapping not only meets the different charging and replacement needs of electric vehicle users, but also takes into account the economic benefits of the charging station operating company and the safety of the power grid. In this paper, by analyzing the electrical structure and operation mode of the integrated charging station, and establishing the operation model of each system, this paper proposes a collaborative optimization Dispatching strategy that aims at the minimum operating cost of the integrated charging station, using particle swarm optimization (PSO) algorithm to solve the problem, and optimize the grid and energy storage output plan according to the relevant constraints and combined with the grid power price and electric vehicle charging and replacement demand and other relevant predicted values, thereby reducing the operating cost of the integrated charging station and reducing the load of the charging station peak-valley difference.

To solve the problem that RBF neural network parameters are difficult to determine, an improved Canopy-K-means algorithm is proposed to optimize the RBF neural network. By using the density-based Canopy algorithm to roughly cluster the data, the cluster centers of the K-means algorithm are initialized, meanwhile the number of cluster centers is obtained, and the Canopy-K-means algorithm based on the density of samples (CKD) is used to optimize the RBF neural network. Three experiments, including nonlinear function approximation, classification of UCI website datasets, the effluent ammonia nitrogen (NH4-N) prediction in wastewater treatment process were used to verify the effectiveness of the algorithm. The results showed that CKDRBF network had high classification accuracy, strong approximation ability.

This work aims at developing a hot sizing process on composite materials to correct the profiles of composite structures during manufacture. Hot sizing experiments were carried out at 150 °C with different sizing loads and hot sizing periods for L-shaped composite beams made of carbon fiber plain-weave fabric and epoxy resin. To predict the springback in hot sizing process, a corresponding finite element simulation method was developed using stress relaxation equations determined at the same temperature. Excellent agreements between the predicted and observed results were obtained. The effects of the component thickness and 45° ply percentage on the springback rate were investigated by simulation. Springback rate in hot sizing process on composite materials ranges from 60% to 95%. In conclusion hot sizing process is proved to be a valid method for compensation for the process-induced deformation (PID) of L-shaped composite beams.

I-shaped stiffened skin was manufactured by a new co-cured resin film infusion process (co-RFI) with fiber preform stiffener and prepreg skin. One kind of epoxy resin film and four kinds of carbon fiber prepreg were used. Resin flow behavior, processing quality, and mechanical performance were investigated for co-RFI stiffened skin. Sole prepreg/autoclave process and resin film infusion process were also adopted for comparison. Resin flow front and resin pressure were detected by self-developed monitoring systems. Optical micrographs and thickness measurement were employed to evaluate processing quality. Moreover, pull-off test was used to analyze the influences of core filler and prepreg systems in skin on the mechanical performance of stiffened skin. The results show that with reasonable processing conditions, good processing quality, and mechanical property at co-curing interface region can be achieved for co-RFI stiffened skin. Co-RFI process is suitable to fabricate composite structure with high flexibility in materials and structures.

In this paper, a LCC series-parallel resonant converter is designed for the electromagnetic launch system, in which, the power supply charges for the energy-storage capacitor in the Pulse Forming Unit. At first, the operational principles of the LCC resonant topology operating in Discontinuous-Current-Mode are analized and the detailed expressions describing the resonant topology are derived. In order to attain the Zero-Current-Switch characteristics in DCM, traditional pulse frequency modulation always restricts the up-band of switches operating frequency, this results in a decrease in output averaged current with the increase of PFU capacitor voltage. This affects the PFU charging efficiency greatly. While, it is an efficient way to solve this problem using the modulation of critical-DCM to extend frequency up-band, which can improve the duty ratio of the output current, ensure the charging efficiency. In this paper, an equivalent simplified linear function is developed to fit with the critical-DCM frequency one, so critical-frequency curve can be tracked online by using Digital-Signal-Processor. The duty ratio of the output current under critical frequency is improved greatly in contrast with traditional PFM. Moreover, in order to obtain a constant current output, a charging current-fed digital PID control scheme in DSP is designed for overcoming the input voltage disturbance and load disturbance. At last, the pictures of energy-storage capacitor charging supply and experiment figures are presented. Simulation and experimental results verify the analysis with good agreement. The designed power supplies realize ZCS soft-switching in the whole operating process, and at the same time, a constant output of charging current is obtained. The expected performance of 0–6kV charging voltage and 1A output current are achieved. The power supply group can be managed by the upper computer through CAN bus.

Given the accuracy of the muzzle velocity of railgun, based on the capacitive energy-stored type of pulse forming network, electromechanical model of railgun is established, a multistage multi-module velocity control strategy based on velocity closed-loop control is proposed. Through the simulate analyze of the multiple of PFU by using electromechanical model of railgun, the best PFU electrical parameters and the best multi-stage control strategy are obtained, test shows that the system model and the control strategy can be applied to the actual system experiment, and achieve good results.

A graded composite strip with elastic variation in span direction is investigated in the paper. So far, studies about materials variation in span direction are rare. Here, the strip is treated as a plane problem, and the modulus varies exponentially with span direction, and Poisson ratio is constant. By using Fourier decomposition in complex form, the series solution for the strip is obtained and is verified by finite element model.

In this paper, we study the application of maximum entropy in engineering structural optimization, and give a detailed analysis on the optimization procedure, the example demonstrates that the algorithm of maximum entropy engineering structural optimization is more accurate and its convergence has been improved