Development Of Portable Resonant Voltage Doubling Capacitor Charging Power Supply

With the development of pulse power technology,high-power pulse power systems have been widely used in materials,medical and national defense research.A common way to obtain high-power pulses is to charge a high-voltage pulse capacitor,and then quickly discharge it after obtaining a certain amount of energy,thereby generating a high-power pulse.In the project,the mains input is usually used,the voltage is boosted by the power frequency transformer,and then the DC high voltage output is obtained through the rectifier circuit to charge the high voltage pulse capacitor.However,due to the large size,low efficiency of the power frequency transformer,and the immovability of the mains input,this charging method will cause the entire pulse power system to be too large,the cost will increase,and it will also be limited in practical applications.In many special applications,users have strict requirements on the volume and portability of high-power pulsed power systems.Therefore,research on the portable capacitor charging device is of great significance to the miniaturization and portability of high-power pulsed power systems.Series resonant charging power supply is often used as the preferred capacitor charging topology due to its characteristics such as strong load short circuit resistance,high reliability,and the ability to achieve constant current charging.This article uses the series resonance charging circuit topology as the basic circuit.For portable design requirements,this article designs the input voltage of the capacitor charging power supply as 12V or24V,and considers using a battery to supply power.The power supply operates at a switching frequency of 100k Hz and transmits the same power.The volume of the high-frequency transformer is much smaller than the power-frequency transformer,and the leakage inductance of the high-frequency transformer is used as the resonance inductance to participate in the resonance process,which greatly increases the portability of the capacitor charging device.Aiming at the high boost ratio design requirement of 3kV charging voltage,this paper combines the series resonant charging power supply and the voltage doubling rectifier circuit topology to perform two-stage voltage rise,which greatly reduces the transformer ratio,reduces the difficulty of transformer design and the withstand voltage requirements of rectifier devices.Based on the theoretical analysis of the series resonant charging power supply and voltage doubling rectifier circuit theory,the feasibility of the resonant voltage doubling capacitor charging power supply is verified through simulation experiments.The principle design and PCB design of a portable resonant voltage doubling capacitor charging device with an input voltage of 12 V and an output voltage of 3 kV are developed.A prototype of a portable resonant voltage doubling capacitor charging device is developed.The prototype is tested for charging and the test waveform diagram is given.The charging device can charge a 6μF capacitor to 3 kV in 247.4 ms,with a power density of 0.087 W/cm~3 and a peak output power of 227 W,which meets the design specifications.Aiming at the problems of slow charging speed and unstable driving power supply voltage for the first time,the design of the input voltage and PCB structure of the power supply was improved,and a portable resonant voltage doubling capacitor charging device with an input voltage of 24 V and an output voltage of 3 kV was developed.The improved charging device has been tested to charge a 6μF capacitor to 3 kV within 58.87 ms,with a power density of 0.38 W/cm~3 and a peak power of936 W.The test results verify the correctness of the design.