Chen Weirong

Proton exchange membrane fuel cell modeling based on adaptive focusing particle swarm optimization

According to the modeling principle of proton exchange membrane fuel cell (PEMFC), adaptive focusing particle swarm optimization (AFPSO), which had preferable ability of global search and search rate was proposed to research a set of optimized parameters in the mechanism model. The comparison between experimental results and simulation results demonstrates that AFPSO can make the simulation results fit the experiment data with higher precision and has manifest superiority and validity for estimating the model parameters. Hence AFPSO achieves significant effect for optimizing the model parameters of PEMFC.

Analysis and Evaluation of Three-Stage Twisty Octapole Field Electromagnetic Launcher

In this paper, we propose an improved launch mode called multistage twisty multipole electromagnetic launcher. The twisty multipole magnetic field configuration is resolved, and the group power supply module is considered. The induced eddy current of the projectile is considered, and the analysis of electromagnetic force and torque has been performed. A full 3-D transient motion simulation with multiple degrees of freedom is carried on the three-stage twisty octapole field electromagnetic launcher. The simulation results indicate that the magnetic torque of rotational motion is impressively large and the transverse displacement of the projectile is much little. The torsion option of multistage pole coils makes little influence on axial acceleration force and exit velocity comparing with the appositional configuration. The theoretical analysis and numerical simulations indicate that the projectile is accelerated with spinning motion about its axis which could keep the projectile fly stability. We suggest this launch mode could be applied in the evacuated tube transportation vehicle.

Simulation of traction transformer based on PSCAD / EMTDC

This paper introduces the structures and the principles of three typical models of traction transformer in railway traction power supply system. Through the simulation based on PSCAD / EMTDC, the results show that these models of the traction transformers are reasonable. Furthermore, the traction power supply systems based on autotransformer (AT)model with three traction transformers are simulated respectively in this paper. Also, this paper focuses on the Catenary voltage distribution and the voltage on the train in these traction power supply systems. Compared the theoretical values with the simulation values of these traction power supply systems, the results show the advantages and disadvantages of three traction transformers, and verify the validities of these traction power supply system models which meet the engineering requirements.

Study on integrated automation system of traction substation for express railway lines

The structure and function of integrated automation system of traction substation for express electric railway lines developed by our university are discussed in this paper. The paper mainly describes the function installation of monitoring and communication unit, video monitoring and control unit and intelligent protection, measurement and control unit. Finally, the application of the system to electric railway lines in China is introduced.

Back-to-back PV generation system for electrified railway and its control strategy

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.