Research On High Voltage Gain Floating-output Interleaved-input Boost Converter Using Coupled-inductor

Renewable energy power generation system requires high gain boost converter.The conventional boost converter can not achieve a high voltage gain due to the equivalent series resistance,and it always used in applications where on need high voltage gain.Therefore,it is valueable to study high gain boost converter.Floating-output Interleaved-input Boost Converter possesses higher voltage gain without extreme duty cycle.Firstly,the working principle and steady state analysis of the Floating-output Interleaved-input Boost Converter are studied.The parameter design process of the converter is given.A comparison is made between four boost converters.Theoretical analysis shows that:(1)Compared with basic interleaved boost converter,Floating-output Interleaved-input Boost Converter has higher voltage gain,and lower voltage stress.(2)Compared with the input-parallel output-series boost converters,Floating-output Interleaved-input Boost Converter has the feature that voltage and current stress of the switches and diodes are more balanced.(3)The input current of all converters is interleaved at the input,reduced the input current ripple.The correctness of the theoretical analysis is verified by Simulation results.Secondly,combined coupled-inductor with Floating-output Interleaved-input Boost Converter,a high voltage gain Floating-output Interleaved-input Boost Converter using coupled-inductor is presented.The ideal working principle and steady state analysis of the converter are studied,and the design procedure of circuit parameters is deduced.Theoretical analysis shows that:(1)The presented converter can achieve high gain by adjusting the coupled-inductor ratio and the duty ratio,respectively.(2)By designing a rational ratio can alleviate device voltage stress effectively.(3)The leakage energy of the coupled-inductor is recycled through the clamp circuit,avoid the voltage spike when the switch turns off.Simulation results verified the correctness of the theoretical analysis.Then,combined the secondary winding of coupled-inductor with voltagedoubler-cell,a improved high voltage gain Floating-output Interleaved-input Boost Converter using coupled-inductor is presented.The ideal working principle and steady state analysis of the converter are studied,and the design procedure of circuit parameters is deduced.Theoretical analysis shows that:(1)The voltage gain of presented converter can be enhanced.(2)The voltage stress of the switches and output diodes are reduced.(3)Improve the utilization of coupled-inductor,the energy can be transferred to the secondary winding no matter the switch in the ON state or OFF state.The correctness of theoretical analysis is verified by simulation.Finally,the closed-loop control system of improved Boost Converter is designed.Completed the design of the control system circuit and software program,and an experimental prototype is builted to verify the correction of the theory analysis.