Research On Boost Converters With Coupling Inductors Interleaved In Parallel

The development of things undergoes a myriad of changes in the twinkling of an eye.Non-renewable energy will be exhausted,and human beings are facing the problem of energy depletion.The rapid development of green renewable energy makes human beings find hope.At present,the main problem is that the output voltage level of clean energy is low and the output voltage range is large,which is not suitable for direct integration into the power grid system.Non-renewable energy power generation,such as hydropower and thermal power,is obviously different from clean energy power generation,the former can be directly connected with the power grid system,and the generated electricity can be combined into the power grid system,but the output voltage of the new energy power generation system must be converted by a step-up converter with sufficient high voltage gain,and then connected to the grid through inversion.Therefore,how to convert the lower voltage level to the higher voltage level of the green renewable energy power generation system has become an important research direction of the new energy power generation grid-connected technology.Based on the principle of quasi Z-source network converter and the interleaved technology,a novel interleaved Boost converter with coupled inductors is proposed in this paper.The MOSFET of the converter can work in the soft switching mode.This Novel converter can achieve high voltage gain at very small duty cycle D.By using coupled inductor and interleaving technology,it has the advantages of low input ripple current,small voltage and current stresses on the MOSFET under high boost ratio.The problem of diode reverse recovery loss in non-synchronous rectifier is overcome by using reverse coupling auxiliary inductor and auxiliary capacitor.At the same time,in the synchronous rectifying state,the auxiliary circuit makes all the switching MOSFETs work in the soft open state.The novel conversion topology can achieve current sharing in each phase.This paper analyzes the working modes of the novel interleaved coupled inductor Boost converter.Firstly,the derivation from the basic Boost converter to the novel interleaved coupled inductor Boost converter is described.The relationship between voltage and current in converter is analyzed in detail under the condition of continuous current,and the main working parameters and waveforms are given.According to the voltage-second balance principle and the ampere-second principle,the relationship between the input voltage,output voltage and duty cycle of the converter is obtained.Secondly,the small signal model of the novel interleaved Boost converter with coupled inductors is established by using the state-average mathematical modeling method,and then the transfer functions of each part are derived.The PID compensation network is analyzed and designed by using the bode diagram of the transfer functions.After determining the closed-loop PID feedback network,the stability analysis is carried out,and the voltage stress relationship of each device is obtained through stability analysis.The research and analysis show that the novel interleaved Boost converter with coupled inductors can achieve higher voltage gain under small duty cycle,the stress of the switching MOSFET is small,and the switching MOSFET works in soft on and soft off state,which greatly improves the efficiency.In This paper,a new type of interleaved Boost converter with coupled inductors is analyzed in theory,the appropriate parameters are designed,the appropriate devices are selected,and the circuit is simulated by using PSIM,Simulink and TINA.The accuracy and feasibility of the theoretical analysis of the novel interleaved Boost converter with coupled inductors are verified.Then the hardware circuit design and PCB design are carried out,and the digital experimental platform based on TMS320F28027 is built to complete the functions of sampling,voltage closed-loop,generating PWM wave,etc.The upper computer of the digital experimental platform is designed by using Matlab,and DSP data transmission,exchange and control are carried out by the upper computer.Finally,a small 300 W prototype is completed for experimental verification.Finally,the simulation and experimental results of the new coupled inductor interleaved Boost converter are analyzed to verify the correctness of the theoretical analysis and applicability of the new coupled inductor interleaved Boost converter.