The modeling and simulation research of fuel cell buses’ power system is an important part of accelerating the process of industrialization. This paper firstly analyzes the advantages and disadvantages of different topologies of power systems to determine the optimal configuration, then conducts the parameter matching study of the power system, derives and determines the main vehicle dynamics parameters and the total power demand of the power system, and further completes the parameter matching of the drive motor, gear ratio and power supply, as well as the design of the fuel cell stack. On the Matlab/Simulink platform, the forward-backward energy flow balance method is used to establish a fuel cell power system model divided into power calculation modules and power shunt modules. Finally, model simulation and comparative analysis was car-ried out. The simulation results of the power system model in this paper were compared with the data of the 2010 World Expo FCB real-vehicle test. The result shows that the simulation results of the dynamic system is in good agreement with the real vehicle data. The power system model conforms to the actual situation, has feasibility and high engineering value.

Unbalanced regional development in China has always been the focus of the government's attention. Agricultural development in China's main agricultural regions is characterized by relatively obvious features, which are mainly manifested in the excessive concentration of agricultural production on one crop or a few agricultural products. Whether this trend of concentration will help to improve the inequalities in China's educational development is an important question for this study. Based on China's population, education and agricultural data over the past 20 years, this paper provides an in-depth analysis of educational inequalities in five typical agricultural-producing provinces by calculating indicators such as the rationalization index of agricultural production structures, the average number of years of schooling of residents and the Gini coefficient of education, in order to analyze the essential reasons for the development of education inequality in major agricultural producing areas. The results show that the urban-rural gap is an important factor affecting the equality of educational development in the main agricultural production areas; the reduction of the rationalization index of agricultural production structure can promote the improvement of inequality in educational development and narrow the urban-rural educational development gap; it also shows that the improvement of specialization in major agricultural producing areas is conducive to reducing educational inequality in major agricultural producing provinces; these conclusions provide a useful reference for narrowing the urban-rural education gap in the main agricultural production areas.

Focusing on Polymer Electrolyte Membrane (PEM) Fuel Cell hybrid Bus (FCB) powertrain integration, this paper presents a quasi-parallel dual-powertrain topology that can enhance powertrain reliability and extend optimization of energy distribution. This paper analyzes the redundancy of three practical topological structures for a dual-powertrain FCB, including a full-parallel structure, a quasi-serial structure, and a quasi-parallel structure. By calculation and comparison, the reliability of the quasi-parallel dualpowertrain structure and its corresponding fault redundancy is shown to be the highest. This paper also carries out an optimization design of FCB powertrain parameters by analyzing the power index and typical Chinese bus cycle. Furthermore, the innovative method of designing power sources is discussed in this paper. Not only power characteristics but also energy characteristics of batteries are fully taken into consideration in this paper. Off-board and on-board experiments verify the feasibility and redundancy of the quasi-parallel dual-powertrain. This research is of reference value for the study of FCB powertrains.

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