A central solenoid model coil will be set up to develop and verify the technique for the full-size central solenoid coil of the China Fusion Engineering Test Reactor.In case of quench and failures of superconducting c...A central solenoid model coil will be set up to develop and verify the technique for the full-size central solenoid coil of the China Fusion Engineering Test Reactor.In case of quench and failures of superconducting coils,the quench protection(QP)system,which employs fuse-based commutation technology,is designed.This paper presents an analytical model to investigate the commutation process in the QP circuit.The model consists of the QP circuit equations,the breaker arc model,the fuse pre-arc model,and the fuse arc model.The model is employed in the whole commutation process including current transfer from breaker branch to the fuse branch model,then from fuse branch to the discharge resistor branch,and current decrease to zero in the discharge resistor.The experiment result verified the effectiveness of the presented model.The model might be helpful for design of the fuse and optimization of the commutation circuit.展开更多
The effects of an external magnetic field originating from two solenoid coils on the magnetic field configuration, plasma state of a dual unbalanced magnetron sputter system and the structure of nanocrystalline Si fil...The effects of an external magnetic field originating from two solenoid coils on the magnetic field configuration, plasma state of a dual unbalanced magnetron sputter system and the structure of nanocrystalline Si films were examined. Numerical simulations of the magnetic field configuration showed that increasing the coil current significantly changed the magnetic field distribution between the substrate and targets. The saturated ion current density Ji in the substrate position measured by using a circular flat probe increased from 0.18 to 0.55 mA/cm2 with the coil current ranging from 0 to 6 A. X-ray diffraction and Raman results revealed that increasing the ion density near the substrate would benefit crystallization of films and the preferential growth along [lI1] orientation. From analysis of the surface morphology and the microstructure of Si films grown under different plasma conditions, it is found that with increasing the Ji, the surface of the film was smoothed and the alteration in the surface roughness was mainly correlated to the localized surface diffusion of the deposited species and the crystallization behavior of the films.展开更多
文摘A central solenoid model coil will be set up to develop and verify the technique for the full-size central solenoid coil of the China Fusion Engineering Test Reactor.In case of quench and failures of superconducting coils,the quench protection(QP)system,which employs fuse-based commutation technology,is designed.This paper presents an analytical model to investigate the commutation process in the QP circuit.The model consists of the QP circuit equations,the breaker arc model,the fuse pre-arc model,and the fuse arc model.The model is employed in the whole commutation process including current transfer from breaker branch to the fuse branch model,then from fuse branch to the discharge resistor branch,and current decrease to zero in the discharge resistor.The experiment result verified the effectiveness of the presented model.The model might be helpful for design of the fuse and optimization of the commutation circuit.
基金partly supported by the project from the State Key Laboratory of Electronic Thin Films and Integrated Devices under grant No.KFJJ200902
文摘The effects of an external magnetic field originating from two solenoid coils on the magnetic field configuration, plasma state of a dual unbalanced magnetron sputter system and the structure of nanocrystalline Si films were examined. Numerical simulations of the magnetic field configuration showed that increasing the coil current significantly changed the magnetic field distribution between the substrate and targets. The saturated ion current density Ji in the substrate position measured by using a circular flat probe increased from 0.18 to 0.55 mA/cm2 with the coil current ranging from 0 to 6 A. X-ray diffraction and Raman results revealed that increasing the ion density near the substrate would benefit crystallization of films and the preferential growth along [lI1] orientation. From analysis of the surface morphology and the microstructure of Si films grown under different plasma conditions, it is found that with increasing the Ji, the surface of the film was smoothed and the alteration in the surface roughness was mainly correlated to the localized surface diffusion of the deposited species and the crystallization behavior of the films.
