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Based on gearless continuously variable transmission technology, a cascaded wind power generation system with Variable Speed Constant Frequency (VSCF) is presented in this paper. The system has combined the advantages of doubly-fed and direct-drive wind power generation system. The raising-speed gear box has been done away with, and the system reliability has been improved. Reducing the power capacity of the aspects of the variable frequency speed regulation, the function of grid-connected electricity generation can be achieved with less cost. Synchronous generator directly connects to grid, which helps to optimize power quality. The topological structure of system is discussed in this paper, and its operating principle is analyzed, revealing its characteristics and engineering application prospects.

Uninterrupted Shift Transmission (UST) is a novel vehicle transmission and which is introduced as the research object in this paper. It realizes torque uninterrupted shift by controlling dual multimode controlled shifter (MCS) modes and synchronizers. Fuzzy control technology is adopted in shift control strategy in order to improve its shift quality. Experimental results show that the fuzzy control strategy can improve the shift quality of UST effectively.

In this paper, the virtual instrument technology is used in torsional vibration study to create a set of torsional vibration natural frequency detection scheme for rotating machinery which is based on the characteristics of controllable one-way overrunning clutch. Also, a test system that is highly sampling frequency, good accuracy and fast data processing capability is developed. This system consists of high-precision dynamic torque sensor, microprocessor-based high-speed data relay module, IPC-based workbench. Finally, the measured results and the calculated results were compared, and it shows that the measured and the calculated results come very close.

In order to make the front and rear axle braking force close to the ideal braking force distribution curves, this paper presents a new idea about the design of automotive brake systems. Firstly, the paper has studied the mathematical conversion relationship from the coordinate of utilization adhesion coefficient and braking strength to the coordinate of the front and rear axle braking force. On this basis, the optimal parameters and constraints complying with ECE regulation are determined. And the optimization objective is the degree of deviation between the curve of actual braking force distribution and the curve of the ideal braking force distribution. Taking a light truck for example, genetic algorithm is used to optimize the vehicle front-rear braking force distribution in the platform of MATLAB. Finally, it is proved that the result of global optimization can meet the design goals.

Working principle of an uninterrupted shift transmission (UST) based on overrunning mechanism and its driveline dynamic model, as well as shift control strategy are studied. For shift quality optimization, the throttle control parameters are calculated based on simplex method and genetic algorithm. Using the control strategy and optimized parameters, simulation results show that jerks and clutch slip during shift are controlled well, satisfactory shift quality is obtained without power flow interruption.

Permanent-magnet synchronous-motor is a muti-variable, non-linear, strong coupling system that is highly sensitive to the outer interfere and inter perturbation. To improve the system robustness, the non-linear mapping is built based on the properties of local time frequency characteristics, zooming index, adaptive study, strong robustness and non-linear approaching of wavelet neural network. By the wavelet neural network the position and speed of rotor is estimated. In the control strategy the sliding mode control is introduced. In this paper the simulation of control strategy is compared with the PI control strategy of PMSM under the same condition. The simulation result shows that the strategy can improve the dynamic and static performance of system.