Multi-port DC/DC Converter For New Energy Hybrid Power Generation

The hybrid system can combine different types of energy in the same system,which caneffectively alleviate social energy pressure.Multi-port DC/DC converter provide effectivecircuit interface unit for hybrid system,more and more scholars pay attention to it.A series ofmulti-port input pulse width-modulation(PWM) dc/dc converters for high-/low-voltagesources is proposed in this paper.According to the synthesised method of multi-port input DC/DC converter,the pulsatingsource cells can be inserted into the buffer devices of the luo-converters,then a new multi-portinput DC/DC converter will be generated.This kind of converters can arbitrarily extendedinput port number, each input port sharing energy buffer uint make the converter reduce thenumber of components of the sysem.Application of voltage lift technique makes the proposedconverter generate high out-put voltage.While another input port embedded buck typeconverter let the system realize the step-down function.Each input port provides power to theload simultaneously or in the different time without affecting each other.The three-por input DC/DC converter which is base on Buck type PWM converter andself-lift luo-converter is analyzed in the paper.The equivalent circuits of different work typesalso are described and compared.Then mathematical formulae describe the characteristicbetween input ports and output port when each input ports works smultaneously orindividually.The voltage and current of every scenario in the proposed converter also arederived.Two one-cycle controllers are designed for the two input ports.Therefore,the closed loopcontrol makes the system have a strong ability against input voltage disturbance.When theopen circuit fault in one of the input ports happened,there is no affection to the normaloperation of the system,which improve stability of system.Finally,the success of theexperiment in the prototype proves the feasibility of the proposed multi-port input DC/DCconverter.