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To obtain spray resistance directly, a prismatic planing hull test was conducted in a towing tank in static water. The characteristic angles of the standing line and leading edge line of the spray zone were obtained through the fixed flight test of the whole prismatic planing hull. The prismatic planing hull was divided into front and rear parts along the standing line, and then the fixed flight state test of the split planing hull was carried out, and the spray resistance was directly measured by the front planing hull. The results show that the percentage of splash resistance in the total resistance is from 15.83 % to 30.10 % under the condition of high-speed planing; Split planing hull model test is an effective method for direct measurement of spray resistance.

Ship model seakeeping test measure data included frequency ponderances of syntonic waves, mixed waves, and white noise, which affect the test result. Heave time series and pitch time series of planning hull model seakeeping test are calculated by the three-parameter sine wave curve-fit method. Amplitude, angular frequency, and phase angle are obtained. The result shows that the distortion degrees of heave and pitch decrease gradually with an increase in wavelength; when the test wavelength is 8.8m, the distortion degrees of heave and pitch are the smallest, which reach 2.79% and 4.69%; however, at a wavelength of 11m, the distortion degrees of heave and pitch increase.

Foreign countries have accumulated rich experience in the research of helicopter floating characteristics. From the model test in the 1950s to the current numerical simulation and extrapolation evaluation, its technical maturity is significantly higher than that in domestic related fields. In order to fully study the influence of wave parameters on helicopter floating characteristics, sort out and refine the model test methods suitable for the study of helicopter floating characteristics, this paper takes a helicopter model as the research object, and carries out the research on the helicopter model test technology with emergency buoys, focusing on the influence range of wave parameters and wave direction on helicopter test results. The results show that the motion response of the helicopter under regular wave conditions presents typical periodic changes. When the helicopter encounters the influence of transverse wave, the rolling amplitude decreases with the increase of wavelength, and the acceleration amplitude of the nose and in the aircraft first increases and then decreases with the increase of wavelength; Under other wave direction conditions, the rolling angle, the acceleration amplitude of the nose and in the machine first increase and then decrease with the increase of the wavelength.

For solving added mass of stratospheric airship, take the method of planar motion mechanism numerical simulation, calculate main diagonal added mass of standard ellipsoid model, and then calculate main diagonal added mass and other coupling added mass of stratospheric airship with X-shaped tail. Error between calculated value and theoretical value is 2.94%~4.29%, that validates the method is feasible and effective; stratospheric airship added mass is expressed by matrix. Comparison with wind tunnel test, the calculation error of stratospheric airship with X-shaped tail added mass λ55 and λ66 are -25.8% and -19.7%. The result shows that the method of planar motion mechanism numerical simulation can solve added mass matrix of arbitrary shape stratospheric airship, not just main diagonal added mass; Compared with the added mass on the main diagonal, the coupling added mass at other positions is small.

In this paper, a Transformer-based fast Monte Carlo reliability evaluation method for integrated energy systems is proposed. First, the faults of the system components are sampled and the corresponding minimum cut load amounts are calculated to obtain the sample data for training the machine learning model. Then, Transformer is used as a machine learning algorithm for mining the nonlinear mapping relationship between system component faults and the minimum cut load, and the estimation model of the minimum cut load under different faults is trained. Finally, the model is combined with Monte Carlo simulation method to randomly sample component states, and for each state, the minimum cut load amount is directly given by the trained estimation model, thus realizing fast evaluation of integrated energy system fast reliability. The proposed method is applied to the integrated energy system test case, which verifies its effectiveness.

In order to solve the problem of wind abandonment and light abandonment in DC microgrid, adding hydrogen production equipment in DC microgrid can effectively alleviate this problem. In the DC microgrid for hydrogen production load, a hierarchical control strategy of DC bus voltage is proposed based on the consideration of charging state, aiming at the fluctuation of DC bus voltage. The operation of the system is divided into seven modes, each of which adopts different control strategies. Finally, a model is built on the PSCAD/EMTDC simulation software and the experimental platform of new energy generation. The simulation and experimental results verify the effectiveness and feasibility of the proposed control strategy.

For the intermittent output of wind turbine and photovoltaic power, aming at the problem of abandoning wind and abandoning light, this paper proposes a DC microgrid system model and control strategy based on hydrogen production load. The DC microgrid system consists of a permanent magnet direct drive wind power system, a photovoltaic power generation system, a buffer energy storage system and an alkaline water electrolysis cell hydrogen production load. The hydrogen production load can adapt to the intermittent fluctuation power supply, make better use of the abandoned wind and light power and be environmentally friendly. Both wind power system and photovoltaic power generation system adopt MPPT control. The battery buffer energy storage device adopts constant voltage charge and discharge control. They are all controlled by their own converters to the DC bus, by producting hydrogen to store the unstable electrical energy generated by distributed generation in the DC microgrid. Based on Matlab/Simulink, results show that the system operates flexibly, the control strategy adopted by the system can maintain the stable operation and load of the system under various power fluctuations and different power supply combinations.