A transformer type iron core snubber, as a protective device against the stray capacitance during the breakdown in EAST, is analyzed in detail. Three kinds of topology are presented. Then with the analysis for equival...A transformer type iron core snubber, as a protective device against the stray capacitance during the breakdown in EAST, is analyzed in detail. Three kinds of topology are presented. Then with the analysis for equivalent circuit, the ranges of three key parameters, i.e., secondary side resistance, leakage inductance and snubber inductance, are determined. By con- sidering the saturation of the magnetic material, a design principle is Mso presented. A nearly 1:10 core snubber is tested. It is proved that a high permeability core with secondary resistor can restrain the discharge current effectively.展开更多
The transformer core snubber (CS), as one of the most important components in the EAST (experimental advanced superconducting tokamak) NBI (neutral beam injector) system, is designed to limit grid damage and pro...The transformer core snubber (CS), as one of the most important components in the EAST (experimental advanced superconducting tokamak) NBI (neutral beam injector) system, is designed to limit grid damage and protect the ion source during periods of electrical breakdowns. A transformer core snubber is analyzed in detail in this paper. Several kinds of soft magnetic cores are presented and compared. With analysis and experiment on the basic characteristics of the cores, the most suitable materials are suggested. The circuit simulation code is established which could simulate faulty conditions with concentrated and distributed CS concepts. Based on the above work, an ion source CS is developed with series type of distributed topology. The CS has been subjected to experimental validation at 80 kV with a peak short-current of approximately 400 A in a real NBI system, which proves the accuracy of the adopted assumptions and the analysis method.展开更多
The core snubber, as a passive protection device, can suppress arc current and absorb stored energy in stray capacitance during the electrical breakdown in accelerating electrodes of ITER NBI. In order to design the c...The core snubber, as a passive protection device, can suppress arc current and absorb stored energy in stray capacitance during the electrical breakdown in accelerating electrodes of ITER NBI. In order to design the core snubber of ITER, the control parameters of the arc peak current have been firstly analyzed by the Fink-Baker-Owren (FBO) method, which are used for designing the DIIID 100 kV snubber. The B-H curve can be derived from the measured voltage and current waveforms, and the hysteresis loss of the core snubber can be derived using the revised parallelogram method. The core snubber can be a simplified representation as an equivalent parallel resistance and inductance, which has been neglected by the FBO method. A simulation code including the parallel equivalent resistance and inductance has been set up. The simulation and experiments result in dramatically large arc shorting currents due to the parallel inductance effect. The case shows that the core snubber utilizing the FBO method gives more compact design.展开更多
A special winding iron-core is designed to act as the snubber for the neutral beam injection (NBI) power supply (PS) system in EAST, which will limit the fault current and energy caused by occasional sparking in t...A special winding iron-core is designed to act as the snubber for the neutral beam injection (NBI) power supply (PS) system in EAST, which will limit the fault current and energy caused by occasional sparking in the NBI ion source. 50-50 Ni-Fe is chosen as the high-frequency magnetization material for the iron-core. Equations for the snubber is derived from the design of the iron-core. The iron-loss factor and eddy-current losses are found to increase in a sample experiment at a frequency from 1 kHz to 20 kHz. A 1:10 miniature of the iron-core is tested and performs well with a fine capability.展开更多
基金supported in part by Auxiliary Heating Project of EAST upgradein part by Ph. D foundation of State Education Ministry of China(No. 20060248012)
文摘A transformer type iron core snubber, as a protective device against the stray capacitance during the breakdown in EAST, is analyzed in detail. Three kinds of topology are presented. Then with the analysis for equivalent circuit, the ranges of three key parameters, i.e., secondary side resistance, leakage inductance and snubber inductance, are determined. By con- sidering the saturation of the magnetic material, a design principle is Mso presented. A nearly 1:10 core snubber is tested. It is proved that a high permeability core with secondary resistor can restrain the discharge current effectively.
基金supported by National Magnetic Confinement Fusion Science Program of China (Nos.2010GB108003, 2011GB113005-1)in part by the National Magnetic Confinement Fusion Science Program of China (No.2010GB108003)+1 种基金the State Basic Research Development Program of China (973 Program 2011GB113005-1)the Large Scientific Project of EAST Auxiliary Heating Upgrade
文摘The transformer core snubber (CS), as one of the most important components in the EAST (experimental advanced superconducting tokamak) NBI (neutral beam injector) system, is designed to limit grid damage and protect the ion source during periods of electrical breakdowns. A transformer core snubber is analyzed in detail in this paper. Several kinds of soft magnetic cores are presented and compared. With analysis and experiment on the basic characteristics of the cores, the most suitable materials are suggested. The circuit simulation code is established which could simulate faulty conditions with concentrated and distributed CS concepts. Based on the above work, an ion source CS is developed with series type of distributed topology. The CS has been subjected to experimental validation at 80 kV with a peak short-current of approximately 400 A in a real NBI system, which proves the accuracy of the adopted assumptions and the analysis method.
基金supported by National Program on Key Basic Research Project of ITER Core Snubber in China (973 Program) (No.2010GB108003)
文摘The core snubber, as a passive protection device, can suppress arc current and absorb stored energy in stray capacitance during the electrical breakdown in accelerating electrodes of ITER NBI. In order to design the core snubber of ITER, the control parameters of the arc peak current have been firstly analyzed by the Fink-Baker-Owren (FBO) method, which are used for designing the DIIID 100 kV snubber. The B-H curve can be derived from the measured voltage and current waveforms, and the hysteresis loss of the core snubber can be derived using the revised parallelogram method. The core snubber can be a simplified representation as an equivalent parallel resistance and inductance, which has been neglected by the FBO method. A simulation code including the parallel equivalent resistance and inductance has been set up. The simulation and experiments result in dramatically large arc shorting currents due to the parallel inductance effect. The case shows that the core snubber utilizing the FBO method gives more compact design.
文摘A special winding iron-core is designed to act as the snubber for the neutral beam injection (NBI) power supply (PS) system in EAST, which will limit the fault current and energy caused by occasional sparking in the NBI ion source. 50-50 Ni-Fe is chosen as the high-frequency magnetization material for the iron-core. Equations for the snubber is derived from the design of the iron-core. The iron-loss factor and eddy-current losses are found to increase in a sample experiment at a frequency from 1 kHz to 20 kHz. A 1:10 miniature of the iron-core is tested and performs well with a fine capability.