For an all solid-state Marx modulator applied in dielectric barrier discharges（DBDs）,hard switching results in a very low efficiency.In this paper,a series resonant soft switching circuit,which series an inductance ...For an all solid-state Marx modulator applied in dielectric barrier discharges（DBDs）,hard switching results in a very low efficiency.In this paper,a series resonant soft switching circuit,which series an inductance with DBD capacitor,is proposed to reduce the power loss.The power loss of the all circuit status with hard switching was analyzed,and the maximum power loss occurred during discharging at the rising and falling edges.The power loss of the series resonant soft switching circuit was also presented.A comparative analysis of the two circuits determined that the soft switching circuit greatly reduced power loss.The experimental results also demonstrated that the soft switching circuit improved the power transmission efficiency of an all solid-state Marx modulator for DBDs by up to 3 times.展开更多
The purpose of impedance matching for a Marx generator and DBD lamp is to limit the output current of the Marx generator,provide a large discharge current at ignition,and obtain fast voltage rising/falling edges and l...The purpose of impedance matching for a Marx generator and DBD lamp is to limit the output current of the Marx generator,provide a large discharge current at ignition,and obtain fast voltage rising/falling edges and large overshoot.In this paper,different impedance matching circuits（series inductor,parallel capacitor,and series inductor combined with parallel capacitor） are analyzed.It demonstrates that a series inductor could limit the Marx current.However,the discharge current is also limited.A parallel capacitor could provide a large discharge current,but the Marx current is also enlarged.A series inductor combined with a parallel capacitor takes full advantage of the inductor and capacitor,and avoids their shortcomings.Therefore,it is a good solution.Experimental results match the theoretical analysis well and show that both the series inductor and parallel capacitor improve the performance of the system.However,the series inductor combined with the parallel capacitor has the best performance.Compared with driving the DBD lamp with a Marx generator direcdy,an increase of 97.3%in radiant power and an increase of 59.3%in system efficiency are achieved using this matching circuit.展开更多
Solid-state circuit breakers(SSCBs)are critical components in the protection of medium-voltage DC distribution networks to facilitate arc-free,fast and reliable isolation of DC faults.However,limited by the capacity o...Solid-state circuit breakers(SSCBs)are critical components in the protection of medium-voltage DC distribution networks to facilitate arc-free,fast and reliable isolation of DC faults.However,limited by the capacity of a single semiconductor device,using semi-conductor-based SSCBs at high voltage is challenging.This study presents the details of a 1.5 kV,63 A medi-um-voltage SSCB,composed primarily of a solid-state switch based on three cascaded normally-on silicon car-bide(SiC)junction field-effect transistors(JFETs)and a low-cost programmable gate drive circuit.Dynamic and static voltage sharing among the cascaded SiC JFETs of the SSCB during fault isolation is realized using the pro-posed gate drive circuit.The selection conditions for the key parameters of the SSCB gate driver are also analyzed.Additionally,an improved pulse-width modulation cur-rent-limiting protection solution is proposed to identify the permanent overcurrent and transient inrush current associated with capacitive load startup in a DC distribu-tion network.Using the developed SSCB prototype and the fault test system,experimental results are obtained to validate the fault response performance of the SSCB.Index Terms—Solid-state circuit breaker,DC distribu-tion network,SiC JFET,voltage balancing,inrush current.展开更多
A design scheme of the intelligent SSB (Solid State Breaker) based on the IGCT (Integrated Gate Commutated Thyris- tor) is presented. The topology of switch module and the structure of the SSB are proposed. Firstly, t...A design scheme of the intelligent SSB (Solid State Breaker) based on the IGCT (Integrated Gate Commutated Thyris- tor) is presented. The topology of switch module and the structure of the SSB are proposed. Firstly, to the IGCT’s over-voltage sensitivity problem, a new technique of reducing the over-voltage is introduced, which releases the elect romantics energy of faulty line by a capacitive current branch to reduce the amplitude of over-voltage. Secondly, the principle of over-voltage suppression with current release branch is analyzed, and the overall control scheme of solid- state breaker is put forward. Finally, the simulation results also demonstrate its obvious effectiveness in over-voltage suppression after adding a current release branch into the SSB.展开更多
基金supported by the Engineering Research Center of Advanced Lighting Technology Ministry of Education
文摘For an all solid-state Marx modulator applied in dielectric barrier discharges（DBDs）,hard switching results in a very low efficiency.In this paper,a series resonant soft switching circuit,which series an inductance with DBD capacitor,is proposed to reduce the power loss.The power loss of the all circuit status with hard switching was analyzed,and the maximum power loss occurred during discharging at the rising and falling edges.The power loss of the series resonant soft switching circuit was also presented.A comparative analysis of the two circuits determined that the soft switching circuit greatly reduced power loss.The experimental results also demonstrated that the soft switching circuit improved the power transmission efficiency of an all solid-state Marx modulator for DBDs by up to 3 times.
基金supported by National Natural Science Foundation of China under the Grant No.51277033
文摘The purpose of impedance matching for a Marx generator and DBD lamp is to limit the output current of the Marx generator,provide a large discharge current at ignition,and obtain fast voltage rising/falling edges and large overshoot.In this paper,different impedance matching circuits（series inductor,parallel capacitor,and series inductor combined with parallel capacitor） are analyzed.It demonstrates that a series inductor could limit the Marx current.However,the discharge current is also limited.A parallel capacitor could provide a large discharge current,but the Marx current is also enlarged.A series inductor combined with a parallel capacitor takes full advantage of the inductor and capacitor,and avoids their shortcomings.Therefore,it is a good solution.Experimental results match the theoretical analysis well and show that both the series inductor and parallel capacitor improve the performance of the system.However,the series inductor combined with the parallel capacitor has the best performance.Compared with driving the DBD lamp with a Marx generator direcdy,an increase of 97.3%in radiant power and an increase of 59.3%in system efficiency are achieved using this matching circuit.
基金supported in part by Hunan Provincial Natural Science Foundation of China(No.2021JJ40172).
文摘Solid-state circuit breakers(SSCBs)are critical components in the protection of medium-voltage DC distribution networks to facilitate arc-free,fast and reliable isolation of DC faults.However,limited by the capacity of a single semiconductor device,using semi-conductor-based SSCBs at high voltage is challenging.This study presents the details of a 1.5 kV,63 A medi-um-voltage SSCB,composed primarily of a solid-state switch based on three cascaded normally-on silicon car-bide(SiC)junction field-effect transistors(JFETs)and a low-cost programmable gate drive circuit.Dynamic and static voltage sharing among the cascaded SiC JFETs of the SSCB during fault isolation is realized using the pro-posed gate drive circuit.The selection conditions for the key parameters of the SSCB gate driver are also analyzed.Additionally,an improved pulse-width modulation cur-rent-limiting protection solution is proposed to identify the permanent overcurrent and transient inrush current associated with capacitive load startup in a DC distribu-tion network.Using the developed SSCB prototype and the fault test system,experimental results are obtained to validate the fault response performance of the SSCB.Index Terms—Solid-state circuit breaker,DC distribu-tion network,SiC JFET,voltage balancing,inrush current.
文摘A design scheme of the intelligent SSB (Solid State Breaker) based on the IGCT (Integrated Gate Commutated Thyris- tor) is presented. The topology of switch module and the structure of the SSB are proposed. Firstly, to the IGCT’s over-voltage sensitivity problem, a new technique of reducing the over-voltage is introduced, which releases the elect romantics energy of faulty line by a capacitive current branch to reduce the amplitude of over-voltage. Secondly, the principle of over-voltage suppression with current release branch is analyzed, and the overall control scheme of solid- state breaker is put forward. Finally, the simulation results also demonstrate its obvious effectiveness in over-voltage suppression after adding a current release branch into the SSB.
