Research On The Key Technologies Of Cascaded Pulse Power Supply

In recent years,pulse power technology has not only played an important role in the field of national defense,but has also received extensive attention from scholars at home and abroad in the field of civilian use.Among them,the technology of generating lowtemperature plasma by the pulse power source as the excitation source has become a research hotspot in the industry.Low temperature plasma has many applications in the surface modification of materials,environmental dust removal,and ignition and combustion support.The output characteristics of the pulsed excitation source have a great impact on the generation of low-temperature plasma.Therefore,the development of highperformance pulsed power supplies has become a key technology for low-temperature plasma applications.In addition,the control and trigger system is also a key technology that restricts the output performance of the pulse power supply.In order to better achieve the flexibility and accuracy of the pulse output,the development of the control and trigger technology has become an important factor.In order to improve the voltage level of the high-voltage pulse power supply and the flexibility of the output pulse voltage,a voltage cascade high-voltage pulse power supply is designed based on the voltage superposition technology.Firstly,based on the principle of source main circuit with an output voltage up to 20 k V was designed.The main circuit consists of 40 identical functional modules,and the output voltage of each module is500 V.Each module realizes DC output by rectifying and filtering the power frequency input voltage,and controls its voltage output through power electronic switches.Secondly,the FPGA is used as the controller,and the man-machine interface is designed to realize the flexible setting of the pulse control and trigger parameters.The photoelectric conversion technology is used to implement the synchronous and asynchronous trigger control of the multi-modules of the main circuit and the effective isolation of high and low voltage.Finally,in order to further reduce the size of the power supply and improve its economy,a new technical solution for the power supply circuit was proposed based on the highfrequency AC-Link technology.The power supply circuit uses high-frequency AC-Link technology to increase the working frequency of the isolation transformer at the power supply end,which can greatly reduce the volume of the transformer and the size of the filter energy storage device.Finally,based on specific design case parameters,simulation experiments and physical experiment verifications were performed for pulsed power supplies with a power frequency Pulse width of 0-50 μs and adjustable repetition frequency between 0-5k Hz.Simulation experiments were performed on the power supply.The experimental results showed that the expected design goals were achieved.