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A new pure rolling-type hole-forming machine for transplanting rapeseed has been developed in accordance with agricultural requirements. The motion of the pure rolling-type mechanism is analyzed to derive parametric equations for the hole-forming mechanism. Computer-aided design and MATLAB are then used to generate theoretical contours and outlines of the transplanting hole. Simulation analysis is conducted to obtain the contours of the transplanting hole, and the resulting structure and motion parameters are verified. Subsequently, a prototype is produced and field testing is performed. Experimental results indicate that, when the machine is in low gear, its forward speed is in the range 1.80–1.96 km/h, corresponding to an operational efficiency of 0.306–0.333 hm2/h. When tested in clay, loamy, and sandy soils, the average qualification rate of hole formation reaches 94.4%, 93.3%, and 90.4%, respectively. These results confirm that the transplanting hole-forming machine developed in this study satisfies the design requirements, representing a significant advance in the provision of technical support for new transplanter designs.

Metro is integral to the urban rail transit with the expansion of the city. Due to the tremendous power consuming of the traction load which is generally considered to be megawatt-class, the attendant problems concerning energy-saving and emission-reduction cannot be neglected. An approach wherein the photovoltaic plants are connected into the metro traction power supply system to provide electrical energy is proposed in this paper. Given the deterioration of power quality brought about by PV connection, the photovoltaic inverter adopts output reactive power control method. The effectiveness of the control strategy which regulates the connection of photovoltaic plants to metro traction power supply system is verified via programming a simulation example in MATLAB/Simulink.

The PV generation application on traction system contributes to promote the nearby accommodation of PV energy and the energy-saving and emission-reduction of traction system. This paper proposed three-phase approach and back-to-back approach for PV generation application on AC powered traction system. Corresponding control principles and energy management strategies were also discussed. The PV energy utilization was simulated using daily traction load data and annual meteorological data. The results showed that back-to-back inverter with improved energy management strategy is of the best performance and the regions with poor irradiation resource could achieve lower abandoned energy ratio.

The integration of PV generation system in traction power supply system contributes to promote the nearby accommodation of PV energy and the energy- saving and emission-reduction of railway system. This paper proposed a back-to-back PV generation system for electrified railway and its control strategy. In the proposed system, PV energy was output using the DC side of back-to-back converter. The optimal power of the two individual converters was calculated dynamically according to the working conditions. Two converters were controlled independently and the PV energy could be output. In the meanwhile, the reactive power and negative sequence current of traction power supply system were compensated to a certain extent taking advantage of the redundant capacity of converters. Simulation model was built in Simulink and the simulation results verified the effectiveness of the proposed system and control strategy.

Test of bench performance to the power of tractor PTO (power take-off ) is a necessary way to evaluate the economic and dynamic performance. So the bracket of engine bench testing is essential equipment, and the effect of DC electric dynamometer used in PTO power test is investigated in this paper. Realizing the process to achieve automatic control and automatic recording, thus greatly reducing the labor intensity of testing personnel and the human error in the testing process, but also greatly increased the accuracy of the test results.

Recently, traditional rules of male sterile lines and restorer lines to regularization planting, with harvesting respectively, labor intensive, uneven pollination, and seriously affecting to the quality and yield of seeds, have been changed by the technology of Engineered Seeding Production, which can reduce the production cost and greatly raise the level of seeds breeding mechanization. But, there are also many problems, in particular, purity of the seeds and high working efficiency are hard to guarantee. So developing a separator is the crux of further popularization. On the basis of parents in different lengths, this paper designs a model Indent Cylinder Separator to study dynamics analysis, and obtains the factors influencing the results of separation are radius, angular velocity and rake angle of the cylinder. Meanwhile, mathematics models between structural, kinetic parameters of the cylinder and different lengths seeds are founded to provide theory basis for further study of structure and parameter design.

There is much difficulty in fault diagnosis because of lacking of system fault samples. So this paper presents a mixed strategy of combining differential evolution algorithm with local enhanced operator with the optimization of the parameters of support vector machine. For the diesel engine valve clearance fault diagnosis, the measured diesel engine valve vibration signals data after wavelet transform are used as the characteristic values of the diagnostic model. Then the diesel engine valve clearance fault diagnosis model of SVM based on MPDE is established and compared with the BPNN, SVM and IQPSO-RBF models, The results showed that the performance of the SVM optimized by MPDE algorithm is better than the models based on the other three algorithms. The method is practical and effective.