Study On Theory And Experiment Of Laser Feedback Power Transmission

System F6attracted more and more interest of researchers with the developmentof satellite technology and aerospace applications growth. Wireless power transmission(WPT) is a key technology of System F6. Laser power transmission which can realizelong-range power transmission is an important method of WPT. It has small systemsand high power density and suitable for space WPT.Laser power transmission is working as application-answer mode in System F6.Energy distribution and transmission are controlled by an energy control center. Intraditional laser power transmission, reducing reflection loss of light injected intophotocell by texturing is one of the most important ways to improve powertransmission efficiency. Nevertheless, this way will increase photocell cost anddifficulty of using and adjustment. It will also increase photocell temperature in space.This paper presents a laser power transmission method which can reuse reflection lossby laser feedback and improve laser power transmission efficiency. The main idea ofoptical feedback laser power transmission is forming a laser resonant cavity betweenthe power transmitter and the power receiver. All of the laser light including thereflection light is constrained in the cavity. The reflection light which is feedback intothe laser will excite more photons and improve efficiency of the laser. It will alsodecrease calorific of the laser.A theoretical model of laser feedback power transmission is set up in this paper.The efficiency of laser feedback power transmission is simulated. By the simulationresult, the threshold current of the laser is reduced by25%with laser feedback powertransmission. The optical power is increased by48%at laser driving current of30mAand receiver reflection of10%.A laser power transmission experiment has been done using a semiconductor laserand a Si photocell with reflection of6%@940nm. The experimental result shows thatthe efficiency of laser power transmission is improved from4.7%to6%with laserfeedback.Constraining all of the laser beam in the laser resonant cavity is the key factor oflaser feedback power transmission and we hope more light can be feedback into the transmitter. The energy feedback rate of a spherical reflector and a cube-corner prismat a situation of long-distance and disorder is simulated by ZEMAX. The simulationresults show that, the spherical reflector has a high reflection rate but pooranti-disorder performance. It is suitable for laser power transmission with high attitudecontrol and orbit control ability. The cube-corner prism has lower reflection rate,however, strong anti-disorder performance. So it is suitable for satellite laser powertransmission with weak attitude control and orbit control ability.