In order to study the relationship between the triggering current, deuterium pressure and the excess heat, a series of experiments were made in a D/Pd gas-loading system. By comparing the system constants （k = AT//kP...In order to study the relationship between the triggering current, deuterium pressure and the excess heat, a series of experiments were made in a D/Pd gas-loading system. By comparing the system constants （k = AT//kP） in both nitrogen and deuterium atmosphere we found an optimum current （8 A） and a deuterium pressure （9 x 104 Pa） in which the system could release a maximum excess power （more than 80 W）. The reproducibility was 16/16 and the excess energy released in the longest experiment was about 300 MJ within 40 days, which was corresponding to 104 eV for each palladium atom. Analysis of the palladium surface with a SEM （scanning electron microscopy） and an EDS （energy dispersive spectrometer） revealed that some new surface topographical feature with concentrations of unexpected elements （such as Ag, Sn, Pb and Ca） appeared after the current triggering. The results implied that the excess heat might come from a nuclear transmutation.展开更多
We present a comparison of data obtained during testing of lightning protective system of a residential structure in rocket-triggered lightning experiment at the International Center for Lightning Research and Testing...We present a comparison of data obtained during testing of lightning protective system of a residential structure in rocket-triggered lightning experiment at the International Center for Lightning Research and Testing(ICLRT)at Camp Blanding,Florida,and current surge generator experiment at Rzeszow University of Technology in Poland.Three different configurations of LPS were tested in Poland with the dc grounding resistances of the entire system 4.09 Ω(LPS 1a),1.65 Ω(LPS 1b),and 2.88 Ω(LPS 2).For LPS 1a with three ground rods the value of the peak current entering the electrical circuit neutral was about 56% of the injected current peak,and for LPS 1b with two additional ground rods and two 5 m long buried horizontal conductors it was about 16%.For LPS 2 with five ground rods interconnected by a buried loop conductor this ratio was 21%.The current waveshapes in the ground rods differed from the injected current waveshapes and the current waveshapes in other parts of the test system,especially,for poorer-grounding LPS 1a.The surge-generator results are consistent with those of triggered-lightning experiments at Camp Blanding,Florida(DeCarlo et al.,2008 [2]).展开更多
The characteristics of the triggered vacuum switch （TVS） are obviously influenced by the emission current ie and emission charge of the trigger device. In this paper, an RC charge collector is designed, and the char...The characteristics of the triggered vacuum switch （TVS） are obviously influenced by the emission current ie and emission charge of the trigger device. In this paper, an RC charge collector is designed, and the characteristics of emission current ie and collecting charge Qc of the trigger device are studied. The experimental results indicate that the emission current ie which is produced by the initial plasma has both positive and negative components, and the polarity of the emission current ie depends mainly on the polarity of the bias voltage UBias. The emission current ie and collecting charge Qe increase with the increase of the trigger voltage Utr and the bias voltage UBias. The emission efficient r] increases linearly with the increase of the bias voltage UBias. When the gap distance is 15 mm and bias voltage UBias is 160 V and trigger voltage Utr is 2.6 kV, the emission efficiency r/reaches 6%展开更多
Characteristics of electron emission induced by a surface flashover trigger device in a low-pressure trigger switch were investigated. A test method to measure the emitted charges from the trigger device was developed...Characteristics of electron emission induced by a surface flashover trigger device in a low-pressure trigger switch were investigated. A test method to measure the emitted charges from the trigger device was developed, and the factors affecting the emitted charges were analyzed. The results indicated that the major emitted charges from the trigger device were induced by surface plasma generated by surface flashover occurring on the trigger dielectric material. The emitted charges and the peak emission current increased linearly with the change in the trigger voltage and bias voltage. The emitted charges collected from the anode were affected by the gap distance. However, the emitted charges were less affected by the anode diameter. Furthermore, the emitted charges and the peak emission current decreased rapidly with the increase in gas pressure in a range from 0 Pa to 100 Pa, and then remained stable or changed slightly when the increase in gas pressure up to 2400 Pa.展开更多
A crowbar impulse current circuit for testing the switch-type surge protective device （SPD） is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main dischar...A crowbar impulse current circuit for testing the switch-type surge protective device （SPD） is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main discharging switch, and a crowbar pseudospark switch. The active trigger technology was studied in the crowbar impulse current circuit. The circuit monitors the main discharging current and generates a trigger signal at a proper time for the crowbar pseudospark switch operation. The trigger characteristics of the main discharge switch and the crowbar pseu- dospark switch were investigated. By monitoring the preset applied capacitor voltage, the gap distance of the main discharging switch could be adjusted to ensure a discharging delay time less than 2 μs. Equipped with a surface ttashover trigger device made of high relative perimittivity dielectric material BaTiO3 （εr = 3460）, the discharge delay time of the crowbar pseudospark switch is less than 85 ns, and the minimum operating voltage is less than 1% of its self-breakdown voltage. With a storage capacitor of 9 μF , an inductor of 18 μH and a crowbar pseudospark switch, a load of 30 mΩ and an applied capacitor voltage of 40 kV, an impulse current waveform of maximum 25 kA was generated with a rise time and time to half peak value of 17.2 μs and 336μs respectively.展开更多
The spectra with wavelength range of 390 nm to 660 nm of triggered lightning were observed in Guangdong Area using a slitless spectrograph. The characteristics of the lightning spectra during the initial continuous cu...The spectra with wavelength range of 390 nm to 660 nm of triggered lightning were observed in Guangdong Area using a slitless spectrograph. The characteristics of the lightning spectra during the initial continuous current and return strokes were analyzed, and the differences between the metal section and air section of the lightning channel were compared. The results showed that the metal spectra were contained in the metal section during the initial continuous current. As for the lightning channel of the return strokes, the line spectra for both the metal section and the air section were identical;neither of the two sections contained the metal spectra, but the relative intensity of its emission spectrum was different. Owing to different radiation mechanisms, the spectral structures and luminance of the two sections were not the same. Combined with the current data, it was found that there was a good positive correlation between the total spectral strength and the transferred charge. The total intensity of the lightning channel spectrum increased with the height of the channel, indicating that the radiation sequence of the lightning channel was different. High temporal resolution observations showed that the spectral line duration could be divided into three categories, in which the lines with higher excitation energy appear first and decay rapidly, while those with lower excitation energy appear later but last longer.展开更多
Structure of main air discharging switch and a crowbar TVS （triggered vacuum switch） are designed and their triggering characteristics are investigated. The experimental results showed that for TVS the operating vol...Structure of main air discharging switch and a crowbar TVS （triggered vacuum switch） are designed and their triggering characteristics are investigated. The experimental results showed that for TVS the operating voltage range is from 1.3 kV to 120 kV, its maximum delay time is 400 ns and its jitter is 4-10 ns. Based on these results the crowbar 10/350μs （i.e., with a front time of 10μs and a duration of 350 μs） pulse current circuit and its controlling circuit are designed. With a 10μF stored capacitor C and a 6 μF waveform forming induction, a pulse current is generated with a maximum of 100 kA, front time of 10 ns and duration of 350μs. This pulse waveform can be used for testing SPD （surge protective devices）.展开更多
利用无狭缝摄谱技术获取了中国广东一次人工触发闪电通道等离子体的光谱.基于光谱诊断方法确定了该触发闪电通道电流的最大值与最小值分别为30.9 kA和25.6 kA,并采用线性电流衰减传输线模型(modified transmission line with linear cur...利用无狭缝摄谱技术获取了中国广东一次人工触发闪电通道等离子体的光谱.基于光谱诊断方法确定了该触发闪电通道电流的最大值与最小值分别为30.9 kA和25.6 kA,并采用线性电流衰减传输线模型(modified transmission line with linear current decay,MTLL)对电流进行了模拟.在此基础上,采用时域有限差分方法(finite-difference time-domain,FDTD)和传输线模型研究了不同距离处的电场分布特征,并对58 m处产生的电场进行了比较.结果发现:当回击速度取1.3×10^(8) m/s时,辐射电场与实验垂直电场偏差较大,但与FDTD方法模拟的垂直电场符合一致.进一步,采用FDTD方法、偶极子方法、电荷-磁场极限估算法研究了58 m,90 m,1.6 km的磁场分布.与实验数据比较发现:不同计算方法与实验值在58 m和90 m处有一定差异,但在1.6 km处符合一致.展开更多
文摘In order to study the relationship between the triggering current, deuterium pressure and the excess heat, a series of experiments were made in a D/Pd gas-loading system. By comparing the system constants （k = AT//kP） in both nitrogen and deuterium atmosphere we found an optimum current （8 A） and a deuterium pressure （9 x 104 Pa） in which the system could release a maximum excess power （more than 80 W）. The reproducibility was 16/16 and the excess energy released in the longest experiment was about 300 MJ within 40 days, which was corresponding to 104 eV for each palladium atom. Analysis of the palladium surface with a SEM （scanning electron microscopy） and an EDS （energy dispersive spectrometer） revealed that some new surface topographical feature with concentrations of unexpected elements （such as Ag, Sn, Pb and Ca） appeared after the current triggering. The results implied that the excess heat might come from a nuclear transmutation.
文摘We present a comparison of data obtained during testing of lightning protective system of a residential structure in rocket-triggered lightning experiment at the International Center for Lightning Research and Testing(ICLRT)at Camp Blanding,Florida,and current surge generator experiment at Rzeszow University of Technology in Poland.Three different configurations of LPS were tested in Poland with the dc grounding resistances of the entire system 4.09 Ω(LPS 1a),1.65 Ω(LPS 1b),and 2.88 Ω(LPS 2).For LPS 1a with three ground rods the value of the peak current entering the electrical circuit neutral was about 56% of the injected current peak,and for LPS 1b with two additional ground rods and two 5 m long buried horizontal conductors it was about 16%.For LPS 2 with five ground rods interconnected by a buried loop conductor this ratio was 21%.The current waveshapes in the ground rods differed from the injected current waveshapes and the current waveshapes in other parts of the test system,especially,for poorer-grounding LPS 1a.The surge-generator results are consistent with those of triggered-lightning experiments at Camp Blanding,Florida(DeCarlo et al.,2008 [2]).
基金supported by National Natural Science Foundation of China(No.51177131)the Fundamental Research Funds for the Central Universities of China(No.xjj20100159)
文摘The characteristics of the triggered vacuum switch （TVS） are obviously influenced by the emission current ie and emission charge of the trigger device. In this paper, an RC charge collector is designed, and the characteristics of emission current ie and collecting charge Qc of the trigger device are studied. The experimental results indicate that the emission current ie which is produced by the initial plasma has both positive and negative components, and the polarity of the emission current ie depends mainly on the polarity of the bias voltage UBias. The emission current ie and collecting charge Qe increase with the increase of the trigger voltage Utr and the bias voltage UBias. The emission efficient r] increases linearly with the increase of the bias voltage UBias. When the gap distance is 15 mm and bias voltage UBias is 160 V and trigger voltage Utr is 2.6 kV, the emission efficiency r/reaches 6%
基金supported by the New Century Talent Foundation of Ministry of Education of China (NCET-08-0438)
文摘Characteristics of electron emission induced by a surface flashover trigger device in a low-pressure trigger switch were investigated. A test method to measure the emitted charges from the trigger device was developed, and the factors affecting the emitted charges were analyzed. The results indicated that the major emitted charges from the trigger device were induced by surface plasma generated by surface flashover occurring on the trigger dielectric material. The emitted charges and the peak emission current increased linearly with the change in the trigger voltage and bias voltage. The emitted charges collected from the anode were affected by the gap distance. However, the emitted charges were less affected by the anode diameter. Furthermore, the emitted charges and the peak emission current decreased rapidly with the increase in gas pressure in a range from 0 Pa to 100 Pa, and then remained stable or changed slightly when the increase in gas pressure up to 2400 Pa.
文摘A crowbar impulse current circuit for testing the switch-type surge protective device （SPD） is presented. The crowbar circuit consists of a computer control circuit, a trigger voltage pulse generator, a main discharging switch, and a crowbar pseudospark switch. The active trigger technology was studied in the crowbar impulse current circuit. The circuit monitors the main discharging current and generates a trigger signal at a proper time for the crowbar pseudospark switch operation. The trigger characteristics of the main discharge switch and the crowbar pseu- dospark switch were investigated. By monitoring the preset applied capacitor voltage, the gap distance of the main discharging switch could be adjusted to ensure a discharging delay time less than 2 μs. Equipped with a surface ttashover trigger device made of high relative perimittivity dielectric material BaTiO3 （εr = 3460）, the discharge delay time of the crowbar pseudospark switch is less than 85 ns, and the minimum operating voltage is less than 1% of its self-breakdown voltage. With a storage capacitor of 9 μF , an inductor of 18 μH and a crowbar pseudospark switch, a load of 30 mΩ and an applied capacitor voltage of 40 kV, an impulse current waveform of maximum 25 kA was generated with a rise time and time to half peak value of 17.2 μs and 336μs respectively.
基金supported by the Open Fund of the State Key Laboratory of Severe Weather of the Chinese Academy of Meteorological Sciences (Grant No. 2019LASW-B08)as a Basic Research Project of the Chinese Academy of Meteorological Sciences (Grant No. 2015Z006. 2016Z005)
文摘The spectra with wavelength range of 390 nm to 660 nm of triggered lightning were observed in Guangdong Area using a slitless spectrograph. The characteristics of the lightning spectra during the initial continuous current and return strokes were analyzed, and the differences between the metal section and air section of the lightning channel were compared. The results showed that the metal spectra were contained in the metal section during the initial continuous current. As for the lightning channel of the return strokes, the line spectra for both the metal section and the air section were identical;neither of the two sections contained the metal spectra, but the relative intensity of its emission spectrum was different. Owing to different radiation mechanisms, the spectral structures and luminance of the two sections were not the same. Combined with the current data, it was found that there was a good positive correlation between the total spectral strength and the transferred charge. The total intensity of the lightning channel spectrum increased with the height of the channel, indicating that the radiation sequence of the lightning channel was different. High temporal resolution observations showed that the spectral line duration could be divided into three categories, in which the lines with higher excitation energy appear first and decay rapidly, while those with lower excitation energy appear later but last longer.
基金supported by the New Century Talent Foundation of Ministry of Education of China (NCET-08-0438)
文摘Structure of main air discharging switch and a crowbar TVS （triggered vacuum switch） are designed and their triggering characteristics are investigated. The experimental results showed that for TVS the operating voltage range is from 1.3 kV to 120 kV, its maximum delay time is 400 ns and its jitter is 4-10 ns. Based on these results the crowbar 10/350μs （i.e., with a front time of 10μs and a duration of 350 μs） pulse current circuit and its controlling circuit are designed. With a 10μF stored capacitor C and a 6 μF waveform forming induction, a pulse current is generated with a maximum of 100 kA, front time of 10 ns and duration of 350μs. This pulse waveform can be used for testing SPD （surge protective devices）.
文摘利用无狭缝摄谱技术获取了中国广东一次人工触发闪电通道等离子体的光谱.基于光谱诊断方法确定了该触发闪电通道电流的最大值与最小值分别为30.9 kA和25.6 kA,并采用线性电流衰减传输线模型(modified transmission line with linear current decay,MTLL)对电流进行了模拟.在此基础上,采用时域有限差分方法(finite-difference time-domain,FDTD)和传输线模型研究了不同距离处的电场分布特征,并对58 m处产生的电场进行了比较.结果发现:当回击速度取1.3×10^(8) m/s时,辐射电场与实验垂直电场偏差较大,但与FDTD方法模拟的垂直电场符合一致.进一步,采用FDTD方法、偶极子方法、电荷-磁场极限估算法研究了58 m,90 m,1.6 km的磁场分布.与实验数据比较发现:不同计算方法与实验值在58 m和90 m处有一定差异,但在1.6 km处符合一致.
