Application Of SiC MOSFET In Accelerator Power Supply

The High Intensity Heavy-ion Accelerator Facility(HIAF)is one of the "National Twelfth Five-Year" national major scientific and engineering projects proposed by the Institute of Modern Physics,the Chinese Academy of Sciences.The beam quality of the accelerator device is inseparable from the performance of the accelerator power supply.The indicators of current stability,low current ripple,and high efficiency will directly affect the indicators of the magnetic field of the magnet,and then affect the performance indicators of the accelerator beam.Power switching devices,as one of the core components of the power supply,play a large role in power output performance.Compared with Silicon(Si)power switching devices,the third-generation semiconductor switching device silicon carbide metal-oxide-semiconductor field effect transistor(Silicon Carbide Metal-Oxide-Semiconductor Field-Effect Transistor,SiC MOSFET)has a higher band gap width,higher critical breakdown field strength,smaller resistivity,and faster electron saturation drift velocity,which can better adapt to work under high temperature,high pressure,and high frequency conditions.Designing switching power supplies with the same power level,the use of SiC MOSFET switching devices allows the power supply to work at higher switching frequencies.The increase of the switching frequency can not only effectively reduce the volume of the transformer and filter capacitor inductance in the circuit,improve the power density,but also reduce the output current ripple and improve the output current quality of the power supply.In addition to making the system smaller and lighter,SiC MOSFET power devices can also provide higher reliability and overload capabilities with their high-temperature operating capabilities,reducing requirements on cooling systems.The article investigate the related performance of SiC MOSFET and Si IGBT,and design a suitable driver circuit and PCB adapter board for SiC MOSFET based on the differences.According to the needs of the target SiC MOSFET,the article test the driver circuit in various aspects,and then the theoretical calculations and the software simulations were used as the design basis to build a SiC MOSFET / Si IGBT switching power supply prototype test platform.The performance comparison test of the power supply of the two types of switching devices has been carried out.The test results show that compared with the 20 kHz limit switching frequency of the Si IGBT power supply,the SiC MOSFET switching power supply prototype can reach a switching frequency above 50 kHz,and the power loss of SiC MOSFET switching power supply is smaller,the power supply is more efficient.At high switching frequency,smaller ripples can be obtained,which can better meet the requirements of low ripple coefficient of accelerator magnet load.