Research On Power Conditioning System For The Laser Thermonuclear Fusion

Research and development for the facilities of laser thermonuclear fusion is the national science project.The power conditioning system is one of the most important parts. With the capacity increment of thepower conditoning system, better reliability and better technical characteristics are required and higherpower density and easier maintainability of the system are needed. The existent power conditoning systemsof the laser nuclear fusion are small. They usually have simple functions and low density of integration andpoor reliability. The research work of this dissertation is mainly based on the higher performance of thelarger power conditoning system. The merits and drawbacks of traditional power conditoning system are analysed in this dissertation. Thenecessity of employing novel power conditoning system structure is presented. All functions of the powerconditoning system are decompounded according to the requirments of the system for the first time.Self-flashing reason of the ignitron in the new configuration is analysed. The coaxial configuration is usedto improve the ignitron. The operation theory of the coaxial configuration is analysed. An approach for thefast fuse box parameter design is given and the electrical parameter design of discharge loop are alsopresented. Considering the requirement of EMC, layout design of the power conditioning module ispresented. It is proved that the average charge current of high-frequency series resonant capacitor charging powersupply (CCPS) is invariable. The series resonant CCPS possesses strong ability of resiting short circuit Itcan be used in the sence of high voltage. The voltage precision can be improved by adopting three-levelseries resonant CCPS. Several driving control schemes are proposed and compared in this dissertation. A novel double series resonant CCPS and its control schemes are firstly put forward. The electricalcharacters of different control schemes are analyzed. It is also indicated that the average charging current isconstant and possesses strong ability of resiting short circuit. The resonant current is independent of theoutput voltage. Because the toplogy have a couple of resonant circuits and each resonant circuit can workindependently and the average charging current is constant, the charge current can be changed by selectingrensonant circuit even if the switching frequency is fixed. And the charge accuracy can be improved byselecting diferent resonant parameters because the resonant circuits are independent. Because the time ofthe charging current is a half period in each resonant period, the precision of charging current is improvedessentialy. And low current harmonics and high efficiency and low resonant current can be achieved byusing the novel topology and control schemes. It can be used in the scenes which require higher precisionand higher power grade. Systematic analysis of the series-parallel resonant capacitor charging power supply is firstly given. IIISome useful characteristics of the series-parallel resonant charging power supply are obtained. If the ratioof the parallel resonant capacitor and the series resonant capacitor is equal, the ratio of the average workingcharging current and the average charging current when the output is short is the function of the ratio of theoutput voltage and the input voltage. The ratio of the positive period or the negative period of the resonantcurrent and the resonant period when the output is short is the function of the ratio of the output voltage andthe input voltage. The average charging current lessens when the output voltage increases. Diagram methodfor designing resonant parameters design fleetly is proposed. Also, the proposed method can be used in theseries resonant CCPS parameters design and power supply debugging. So the defect of the traditionalseries-parallel resonant parameters design method can be overcome. Influences of the step-up transf...