Research On High Voltage Gain DC-DC Converters In Solar Unmanned Aerial Vehicle

With the development of solar energy conversion technique,the requirements of high endurance time and long mileage require the weight of power system should also be reduced and the efficiency of them should be improved as much as possible.Nowadays,with the emergence of high voltage gain converter technique,it is significant to study the application of this technique in the solar UAV because its advantage to simplify this system.In this paper,a high voltage gain DC-DC converter was analyzed first.Then,its working principle was studied.The advantage of the converter’s voltage gain were calculated and presented in this paper,and this can reduce the size of the power system.In order to verify the performance of the converter in specific application,a maximum power point tracking(MPPT)system based on high voltage gain DC-DC converter is designed.The maximum power point tracking is realized in the simulation system by design appropriate parameter.Similarly,in the actual PV arrays MPPT experiment,the converter also shows a high voltage step-up capacity,proving that it can be used as a suitable photovoltaic cell interface converter.After that,a bidirectional high voltage gain DC-DC converter which can be applied to the battery energy storage system is designed.The proposed converter can realize a high voltage gain with a low turn ratio of the coupled inductor.And the voltage stress of switches were also reduced.By utilizing the synchronous rectifier technique,switches in this converter can achieve zero-voltage switch(ZVS)to reduce system’s losses.This design process also expand the idea of how to design a non-isolated bidirectional DC-DC converter.The specific analysis and calculation process verify the proposed advantages,which shows its broad application prospects in the battery energy storage system.In the end,an energy battery charging and discharging control system with a bidirectional high voltage gain DC-DC converter is designed.And a battery charging and discharging control method is also designed.Finally,the Simulink simulation experiment result and piratical experiment show that the proposed bidirectional DC-DC converter can satisfy the task of battery charging and discharging well in this system.At the same time,it also proves the practicability of the control method.