Research On A Novel Three-port Converter

Three-port converters have some advantages such as high efficiency,high power density,high reliability and low cost.In this paper,a novel three port converter(TPC)is proposed,which is applied to a stand-alone renewable power system with high voltage gain.Firstly,this paper introduces the background and significance of the research,and the development status and direction of three port converter at home and abroad.A novel three port converter is proposed,which is applied to a stand-alone renewable power system with high voltage gain.This converter uses only three switches to realize power flow control,and two input sources share one inductor.Thus,the volume will be reduced.Besides,the conversion rate of the converter is also higher than that of the other three port converters.Phase-shift control strategy with UC3875 is described in detail in this article,driven by opto-isolator to achieve conversion to get meet the PWM pulse signal to the main circuit.The proposed converter can draw power from two different sources and transfer it to the load simultaneously and individually.Moreover,the feasibility of the new three port converter is verified by simulation in Multisim.In this paper,the topology and operational principle of several common three port converters are listed.The operational principle of the three port converter is analyzed,and its advantages and disadvantages are analyzed.Secondly,the working principle and working mode of the converter are analyzed,including the single input single output mode(SISO),the dual input single output mode(DISO)and the single input dual output mode(SIDO)under different working modes.Thirdly,the logic control of the converter is designed based on the phase-shift PWM phase shift control.Finally,the main components of the converter are designed,and the experimental prototype is built.The logic controller STM32 is used to realize the control,and the experimental results verify the working principle of the converter and the effectiveness of the control.In this paper,the operation principle,steady state analysis and control method of the three port converter are presented.In order to verify the feasibility of the theoretical analysis,a prototype with a low input voltage 24 V for photovoltaic source,a battery port voltage 48 V,and an output voltage 400 V is implemented.