In the reversely switched dynistor(RSD)-based pulse power circuits,a magnetic switch is usually necessary to be applied together with a main switch.It occupies space and needs a magnetic reset.In this paper,a method o...In the reversely switched dynistor(RSD)-based pulse power circuits,a magnetic switch is usually necessary to be applied together with a main switch.It occupies space and needs a magnetic reset.In this paper,a method of designing a RSD-based pulse circuit without a magnetic switch is proposed.In the pulse circuit,a RBDT(reverse blocking diode thyristor)is used to separate the two capacitors and provide an energy branch.The pre-charge time of the RSD can be guaranteed by the energy conversion between the capacitors and inductors,instead of the saturation of the magnetic switch.In addition,the energy which is reused to trigger the RSD is based on an inductor.The pulse circuit is evaluated by simulations and practical experiments.According to the experimental results,the factors affecting the load pulse current and triggering of the RSD and RBDT are studied.Meanwhile,a method to reduce the current in the trigger switch,which is a potential problem in the pulse circuit,is proposed.展开更多
To date, the high power arc plasma technology is widely used. A next generation high power arc plasma system based on building block structure is presented. The whole arc plasma inverter system is composed of 12 paral...To date, the high power arc plasma technology is widely used. A next generation high power arc plasma system based on building block structure is presented. The whole arc plasma inverter system is composed of 12 paralleled units to increase the system output capability. The hierarchical control system is adopted to improve the reliability and flexibility of the high power arc plasma inverter. To ensure the reliable turn on and off of the IGBT module in each building block unit, a special pulse drive circuit is designed by using pulse transformer. The experimental result indicates that the high power arc plasma inverter system can transfer 300 kW arc plasma energy reliably with high efficiency.展开更多
A few traditional pulse-forming circuits are implemented in a commercial 0.13 μm digital complementary-metal-oxide-semiconductor （CMOS） technology. These circuits, based on a coplanar waveguide, are analyzed and co...A few traditional pulse-forming circuits are implemented in a commercial 0.13 μm digital complementary-metal-oxide-semiconductor （CMOS） technology. These circuits, based on a coplanar waveguide, are analyzed and compared through CadenceTM Spectre simulations. The results show that these traditional pulse-forming-line （PFL） based circuits can be implemented in standard CMOS technology for short pulse generations. Further work is needed to explore the potential of the circuit techniques and to minimize parasitic effects.展开更多
Two new kinds of ultra-narrow trigger frequency alterable picosecond pulse generator are presented.One can produce positive pulses and the other can produce negative pulses.The two pulse generators are subdivided into...Two new kinds of ultra-narrow trigger frequency alterable picosecond pulse generator are presented.One can produce positive pulses and the other can produce negative pulses.The two pulse generators are subdivided into three parts:signal driving circuit,differentiator network and pulse shaping circuit.The pulse shaping circuit is made of step recovery diode(SRD) and short-circuit microstrip line.A positive pulse with width of 54 ps(50%-50%),rising time of 30 ps(10%-90%) and falling time of 32 ps(90%-10%),and a negative pulse with width of 54 ps(50%-50%),rising time of 30 ps(90%-10%) and falling time of 30 ps(10%-90%) are achieved in simulation.All of the components are ready-made and inexpensive.They can be applied in ultra-wideband(UWB) communication system,such as transmitters and receivers.展开更多
A nanosecond square pulse fiber laser based on the nonlinear amplifying loop mirror （NALM） is numerically analyzed by the nonlinear SchrSdinger equation. The fiber cavity with a NALM has a tendency to provide pulse ...A nanosecond square pulse fiber laser based on the nonlinear amplifying loop mirror （NALM） is numerically analyzed by the nonlinear SchrSdinger equation. The fiber cavity with a NALM has a tendency to provide pulse shaping effect with nonlinearity increasing in the NALM, and the nanosecond square pulse is generated by the pulse shaping effect. The numerical results show that the stable square pulse can be obtained when the parameters of the NALM are chosen appropriately. The generated square pulses have fiat top and no internal structure.展开更多
The multi-phase particle swarm optimization （MPPSO） technique is applied to retrieve the particle size distribution （PSD） under dependent model. Based on the Mie theory and the Lambert-Beer theory, three PSDs, i.e...The multi-phase particle swarm optimization （MPPSO） technique is applied to retrieve the particle size distribution （PSD） under dependent model. Based on the Mie theory and the Lambert-Beer theory, three PSDs, i.e., the Rosin-Rammer （R-R） distribution, the normal distribution, and the logarithmic normal distribution, are estimated by MPPSO algorithm. The results confirm the potential of the proposed approach and show its effectiveness. It may provide a new technique to improve the accuracy and reliability of the PSD inverse calculation.展开更多
基金This work was supported by the National Natural Science Foundation of China(51877092,51377069).
文摘In the reversely switched dynistor(RSD)-based pulse power circuits,a magnetic switch is usually necessary to be applied together with a main switch.It occupies space and needs a magnetic reset.In this paper,a method of designing a RSD-based pulse circuit without a magnetic switch is proposed.In the pulse circuit,a RBDT(reverse blocking diode thyristor)is used to separate the two capacitors and provide an energy branch.The pre-charge time of the RSD can be guaranteed by the energy conversion between the capacitors and inductors,instead of the saturation of the magnetic switch.In addition,the energy which is reused to trigger the RSD is based on an inductor.The pulse circuit is evaluated by simulations and practical experiments.According to the experimental results,the factors affecting the load pulse current and triggering of the RSD and RBDT are studied.Meanwhile,a method to reduce the current in the trigger switch,which is a potential problem in the pulse circuit,is proposed.
基金supported by National Natural Science Foundation of China (50805051)Guangdong Provincial Science and Technology Project (2008B010400041)
文摘To date, the high power arc plasma technology is widely used. A next generation high power arc plasma system based on building block structure is presented. The whole arc plasma inverter system is composed of 12 paralleled units to increase the system output capability. The hierarchical control system is adopted to improve the reliability and flexibility of the high power arc plasma inverter. To ensure the reliable turn on and off of the IGBT module in each building block unit, a special pulse drive circuit is designed by using pulse transformer. The experimental result indicates that the high power arc plasma inverter system can transfer 300 kW arc plasma energy reliably with high efficiency.
文摘A few traditional pulse-forming circuits are implemented in a commercial 0.13 μm digital complementary-metal-oxide-semiconductor （CMOS） technology. These circuits, based on a coplanar waveguide, are analyzed and compared through CadenceTM Spectre simulations. The results show that these traditional pulse-forming-line （PFL） based circuits can be implemented in standard CMOS technology for short pulse generations. Further work is needed to explore the potential of the circuit techniques and to minimize parasitic effects.
基金the National Natural Science Foundation of China (No.60970058)the Natural Science Foundation of Jiangsu Province (No.SBK200930425)+1 种基金the fund of the State Key Laboratory of Millimetre Waves of Southeast Universitythe Student Research Training Program (SRTP) of Southeast University
文摘Two new kinds of ultra-narrow trigger frequency alterable picosecond pulse generator are presented.One can produce positive pulses and the other can produce negative pulses.The two pulse generators are subdivided into three parts:signal driving circuit,differentiator network and pulse shaping circuit.The pulse shaping circuit is made of step recovery diode(SRD) and short-circuit microstrip line.A positive pulse with width of 54 ps(50%-50%),rising time of 30 ps(10%-90%) and falling time of 32 ps(90%-10%),and a negative pulse with width of 54 ps(50%-50%),rising time of 30 ps(90%-10%) and falling time of 30 ps(10%-90%) are achieved in simulation.All of the components are ready-made and inexpensive.They can be applied in ultra-wideband(UWB) communication system,such as transmitters and receivers.
文摘A nanosecond square pulse fiber laser based on the nonlinear amplifying loop mirror （NALM） is numerically analyzed by the nonlinear SchrSdinger equation. The fiber cavity with a NALM has a tendency to provide pulse shaping effect with nonlinearity increasing in the NALM, and the nanosecond square pulse is generated by the pulse shaping effect. The numerical results show that the stable square pulse can be obtained when the parameters of the NALM are chosen appropriately. The generated square pulses have fiat top and no internal structure.
基金the National Natural Sci-ence Foundation of China (No.50576019)the Pro-gram for New Century Excellent Talents in University from the Ministry of Education of China.
文摘The multi-phase particle swarm optimization （MPPSO） technique is applied to retrieve the particle size distribution （PSD） under dependent model. Based on the Mie theory and the Lambert-Beer theory, three PSDs, i.e., the Rosin-Rammer （R-R） distribution, the normal distribution, and the logarithmic normal distribution, are estimated by MPPSO algorithm. The results confirm the potential of the proposed approach and show its effectiveness. It may provide a new technique to improve the accuracy and reliability of the PSD inverse calculation.
