Research On High Frequency Low Disturbance Pulsed-power Supply

Pulsed power technology is aimed to transmit vast amounts of energy in the storage device to the load quickly and reliably through the switch to make the load work normally.At present,the research on pulsed power technology mainly focuses on the research of pulsed power supply and pulsed power load.Pulsed power load has been widely used in spacecraft,radar,communication power supply and other fields.The pulsed power load has the characteristics of high peak power and low average power.When the power supply works under pulsed load conditions,the output voltage will have a large amplitude voltage drop,and also cause low-frequency pulsation of the input current,generating current electromagnetic interference,affecting the normal operation of other equipments.At the same time,the pulsed power converter is aimed to realizing high frequency,high efficiency and miniaturization.In order to solve the above problems,this subject designed a cascade pulsed load power supply with high switching frequency and implement simulation research.Aiming at the problems that may occur in pulsed power converters under pulsed load conditions,this dissertation uses floating voltage capacitors as pulsed energy buffer devices,and uses Boost converter and double-switch forward converter in cascade to form isolated pulsed power converters.The pre-stage Boost converter provides the average power required by the pulsed load,its' output capacitor is the floating voltage capacitor and provides the dynamic power required by the pulsed load,and the post-stage two-switch forward converter is used for output voltage regulation.An improved peak current control method is proposed to directly control the input current of Boost converter to solve the low-frequency disturbance of input current,.In order to improve the dynamic response of the pulsed power converter,while the post-stage double-switch forward converter uses GS61008 P Ga N devices work at the switching frequency of 1 MHz,a variable inductance double-switch forward converter structure is proposed.The small output inductance mode works in the transient process and the large output inductance mode works in the steady state process,thereby accelerating the transient process of the power supply and improving the dynamic response.The double-switch forward converter uses a passive and lossless soft-switching double-switch forward converter structure to realize soft turn on/off,in order to reduce the switching loss of Ga N switchs and improve the reliability and efficiency of the pulsed power supply.The first generation low switching frequency prototype is used to verify the pulse load characteristics,and the drive circuit of GS61008 P gallium nitride transistor based on SI8271 isolated drive chip is designed.The designed high frequency cascade pulsed power converter circuit is built in Saber simulation software,and the time domain simulation is carried out.It is proved that the designed pulsed power converter can effectively suppress the disturbance of the input current,and has high dynamic response and low switching loss.