Research On Design And Predictive Control Strategy Of LCL Interleaved Boost Converter

With the excessive consumption of non renewable resources,such as coal,oil and natural gas,and the increasingly serious environmental pollution,it is imminent to study the renewable and environmental new energy.The new energy sources,such as photovoltaic power generation,wind power generation and fuel cell,have been developed very well.The micro network and grid system of new energy sources,such as solar power and fuel cells,have been widely used.In these systems,the DC-DC converter is required to achieve different voltage conversion,and the input voltage range and the quality of the DC-DC converter are higher.How to improve the ratio of output voltage to the input voltage and the optimal control method is of great significance.In order to improve the ratio of the output voltage to the input voltage of the traditional Boost converter,reduce the voltage stress of the switch device and the ripple of the inductor current,an improved LCL staggered parallel Boost converter is designed.The LCL unit is proposed to convert the diode of the switch inductance unit to the capacitor,which makes the boost effect better and integrates the inductance of the LCL unit.Through the analysis of the working principle and performance of the converter,the boost device increases the ratio of the output voltage to the input voltage,the maximum increase when D>0.5 is 4 times that of the traditional Boost converter;the coupling integrated inductor reduces the current ripple by 53.13%,the voltage stress of the switch tube decreases,the D>0.5 decreases MOSFET and is half the output voltage.The fault detection of the converter is also studied.The influence of MOSFET transistor and diode open circuit short circuit on the converter is discussed,and the performance test of the converter is summarized.In order to improve the quality of output power,the model predictive control method is adopted.The state equations of the converter at D<0.5,D>0.5 and the equivalent series resistance of inductance and the equivalent series resistance of inductor are considered respectively.The prediction model of the output voltage VR and inductance current iL is established,and then the VR and iL of the next sampling time of the lift under the different working modes are predicted.The simulation is carried out in the Matlab Simulink simulation environment.The results show that the VR and iL of the next sampling time can be accurately predicted.Finally,an improved 100 W LCL interleaving Boost converter booster is designed to verify the correctness of the theoretical analysis.