Research On Key Technologies Of Powertrain System For Fuel Cell Tram

With the rapid economic development and accelerating urbanization in our country,the energy crisis,environmental pollution and traffic congestion problems brought by car as the main traffic mode have become more and more serious.The high-capacity rail transit is regarded as the development focus of the urban public traffic.Trams have high capacity as subways and are as convenient as buses.Fuel cells have high efficiency,null emission of polluting agents and save energy.Therefore,trams powered by fuel cells have attracted attention by researchers both at home and abroad in recent years.The engineering background of this paper is the development of prototype 1 and 2 for two sections of the project of "hydrogen fuel cell hybrid trams" by Tsinghua University cooperated with CRRC Qingdao Si-fang Locomotive Co.,LTD.By applying methods of system modeling,test verification and optimal control theory,the research was carried forward from power components,power-train systems,a tram,a tram team to the tram industry aspects,aiming at resolving the key techniques of the fuel cell tram to ensure tram safety,improve fuel economy and component durability.The main contents are as follows:(1)Two configurations of the fuel cell trams of "fuel cell + battery+ super-capacitor" and "fuel cell + battery" were comparatively analyzed.Models of each component of the powertrain system were established.Considering the fuel cell tram characteristics such as large weight,high accessory power and braking power,a joint optimization algorithm combining power distribution and parameter matching was proposed.The optimal parameter combination of fuel cell power and battery capacity was then obtained.The research results were applied to the new tram prototype.(2)The powertrain system was arranged on the roof of the fuel cell tram.The hydrogen supply system and the colling system were integrated to save roof space.The control system was developed and the MVB communication between main controller and energy controller was tested.For emergent CAN network failure problem,a fault tolerant control method transferring the control right of the energy controller to the DC/DC controller was carried out.The powertrain system were successfully debugged and the whole system reliability were then verified.(3)Since the catenary was wiped off and on-board hydrogen gas storage is limited,no continuous power was supplied for the fuel cell tram,it requires several times for hydrogen refueling.The paper analyzed the operation modes' switching mechanism of hydrogen refueling,battery recharging and on-line running in daily operation.Dynamic programming strategy was applied to optimize the tram daily operation modes.Genetic algorithm was introduced to solve the tram team scheduling problem on the condition that the team take turns for hydrogen refueling.(4)The life cycle cost model was set up and variable scaling factors were introduced.The comparative analysis of life cycle costs and greenhouse gas emissions for five types of trams including the catenary,the third rail,induction,energy storage and fuel cell trams indicated that the fuel cell tram had minimum cost and minimum emissions.Therefore,the fuel cell tram project is feasible and profitable.