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A new multi-resources leveling model with risk float time is established in this paper. With presetting the new variable of risk float time at the end of activity float time, the model can realize the new function that the project risk can be considered at the same time the resource leveling process is calculated. The validity of the improved model in this paper is verified with the help of genetic algorithm.

A hybrid power system for fuel cell electric vehicles(FCEV) was proposed. The fuel cell and the battery and/or ultracapacitor are connected to the same voltage bus through an appropriate unidirectional dc-dc converter (UDC) and a buck/boost bidirectional DC/DC converter(BDC), respectively. The battery and the ultracapacitor are auxiliary energy source, which provides or absorbs the dynamic power when the load varies and the fuel cell cannot respond immediately, so the system dynamic characteristics are improved. A multiple input dc-dc converter (MIDC) devoted to combine the power flowing from combined on-board energy sources is presented; Finally, the analysis and design validation are verified through the simulation and experiment.

Photovoltaic energy has nowadays an increased importance in electrical power applications. However, the output power provided via the photovoltaic conversion process depends on solar irradiation and temperature. Therefore a multiple-input DC/DC converter is proposed for stand-alone photovoltaic lighting system with battery storage in this paper. Compared with the traditional stand-alone photovoltaic system, which merely use one muti-input biderictional DC/DC converter control the battery charge or discharge effectively, protect battery and prolong its natural life as well as have high conversion efficiency and low cost for photovoltaic lighting system. Muti-input converter implements bi-directional energy transfer in the system, so the key of energy management is control bi-directional converter effectively. Finally the simulation and experimental verifications are also presented.

The fuel cell and the accumulator and/or super-capacitor are connected to the same voltage bus through an appropriate multiport DC/DC converter, in fuel cell electric vehicle. The accumulator and/or the super-capacitor are auxiliary energy source, which provides or absorbs the dynamic power when the load varies and the main power supply cannot respond immediately, so the system dynamic characteristics are improved. A multiple port dc-dc converter (MPDC) devoted to combine the power flowing from combined on-board energy sources is presented; Eventually, the analysis and design validation are verified via the simulation and experiment.