Frequency response characteristics of self-integralting capacitive divider
-
摘要: 为了测量电缆中传输的ns量级脉冲高电压,设计了自积分电容分压器并开展了频率响应特性分析。为分压器设计了不同的补偿电阻,并使用含有杂散参数的等效电路进行分析。仿真结果表明:分压器低频特性的主要影响因素是等效取样电阻与低压臂电容乘积得到的时间常数;高频特性主要受电容的杂散电感和取样电阻的杂散电容影响。增大时间常数扩展低频特性时,会导致杂散参数的影响加剧而使分压器高频特性变差。采用方波实验和扫频测量两种方法实测了不同参数分压器的频响特性。结果表明:补偿电阻为550 Ω的电容分压器频响上限超过2 GHz;但是低频特性不足,频率下限约为1.8 MHz;而补偿电阻为6.6 kΩ,且调整结构的电容分压器带宽为0.17~700 MHz,能够满足测试需求。Abstract: A self-integrating capacitive divider has been designed to measure the high voltage pulse transmitting in a cable with rising time of 1ns. The frequency characteristics have been analysed by the equivalent circuit that comprises stray parameters of capacitive divider. The main factor affecting the lower limiting frequency is the time constant, i.e., the product of the capacitance of the low-voltage arm capacitor and the resistance of the equivalent load. The upper limiting frequency is chiefly impacted by some stray parameters which stem from the stray inductance of the low-voltage arm capacitor and the stray capacitance of the compensated resistor. To extend the lower limiting frequency the time constant should be increased by enhancing the capacitance or the resistance, however, this often results in the debasement of the upper limiting frequency. Different compensating resistors have been designed. The amplitude-frequency response of the capacitive dividers were measured by network analyzer, meanwhile, experiment with square pulse response was also performed as a contrast. The results indicate that the upper limit of frequency response for capacitive divider with 550 Ω compensating resistance exceeds 2 GHz, however the lower limit is insufficient and about 1.8 MHz. If the compensating resistor is tuned to 6.6 kΩ, the corresponding capacitive divider will have a bandwidth of 0.17-700 MHz which satisfies the demand of measurement.
-
Key words:
- voltage pulse /
- capacitive divider /
- frequency response
-
表 1 电容分压器杂散参数取值表
Table 1. Stray parameters of capacitive divider
No LR/nH Cg/pF 1 20 8 2 20 16.5 3 20 30 4 100 16.5 5 2000 16.5 表 2 补偿电阻的设计参数
Table 2. Parameters of compensated resistor
No R1/kΩ number of resistor in series/ps 1# 9 1 2# 6.6 2 3# 6 3 4# 0.55 1 -
[1] 曾正中. 实用脉冲功率技术引论[M]. 西安: 陕西科学技术出版社, 2003: 157-167.Zeng Zhengzhong. Introduction to practical high power pulse technology. Xi'an: Shannxi Science and Technology Press, 2003: 157-167 [2] Edson W A, Oetzel G N. Capacitance voltage divider for high-voltage pulse measurement[J]. Rev Sci Instrum, 1981, 52(4): 604-606. doi: 10.1063/1.1136644 [3] Wagoner T C, Stygar W A, Ives H C. Differential-output B-dot and D-dot monitors for current and voltage measurements on a 20-MA, 3-MV pulsed-power accelerator[J]. Phys Rev ST Accel Beams, 2008, 11: 100401. doi: 10.1103/PhysRevSTAB.11.100401 [4] 呼义翔, 郭宁, 韩娟娟, 等. 磁绝缘传输线电压测量用自积分式电容分压器研制[J]. 强激光与粒子束, 2013, 25(7): 1839-1844. doi: 10.3788/HPLPB20132507.1839Hu Yixiang, Guo Ning, Han Juanjuan, et al. Self-integral capacitance divider used for voltage measurement along magnetically insulated transmission lines. High Power Laser and Particle Beams, 2013, 25(7): 1839-1844 doi: 10.3788/HPLPB20132507.1839 [5] 高景明, 刘永贵, 杨建华. 一种电容补偿型高压电容分压器的设计[J]. 高电压技术, 2007, 33(6): 76-79. doi: 10.3969/j.issn.1003-6520.2007.06.019Gao Jingming, Liu Yonggui, Yang Jianhua. Design of capacitance-compensated capacitive divider for high-voltage pulse measurement. High Voltage Engineering, 2007, 33(6): 76-79 doi: 10.3969/j.issn.1003-6520.2007.06.019 [6] 丁德胜, 易灵芝, 喻斌雄, 等. 测量强流电子加速器输出电压的电容分压器[J]. 强激光与粒子束, 2012, 24(10), 2497-2501. doi: 10.3788/HPLPB20122410.2497Ding Desheng, Yi Lingzhi, Yu Binxiong, et al. Capacitive divider used for output voltage measurement of intense electron beam accelerator. High Power Laser and Particle Beams, 2012, 24(10), 2497-2501 doi: 10.3788/HPLPB20122410.2497 [7] 张永辉, 常安碧, 甘延青, 等. 一种同轴高压电容分压器的设计[J]. 高电压技术, 2003, 29(1): 37-39. https://www.cnki.com.cn/Article/CJFDTOTAL-GDYJ200301016.htmZhang Yonghui, Chang Anbi, Gan Yanqing, et al. Design of a high voltage coaxial capacitive voltage divider. High Voltage Engineering, 2003, 29(1): 37-39 https://www.cnki.com.cn/Article/CJFDTOTAL-GDYJ200301016.htm [8] Wang Liangping, Han Juanjuan, Li Mo, et al. A compact capacitive probe for high-voltage diagnostic in Z-pinches[J]. Rev Sci Instrum, 2013, 84: 033504. doi: 10.1063/1.4797460 [9] 卫兵, 方东凡, 卿燕玲, 等. 亚纳秒脉冲高电压测量探头[J]. 强激光与粒子束, 2012, 24(6): 1497-1501. doi: 10.3788/HPLPB20122406.1497Wei Bing, Fang Dongfan, Qing Yanling, et al. D-dot monitor for sub-nanosecond high voltage pulse measurement. High Power Laser and Particle Beams, 2012, 24(6): 1497-1501 doi: 10.3788/HPLPB20122406.1497 [10] 全林, 樊亚军, 张永民, 等. 快脉冲二极管运行监测探头研制[J]. 核电子学与探测技术, 2009, 29(2): 267-270. https://www.cnki.com.cn/Article/CJFDTOTAL-HERE200902008.htmQuan Lin, Fan Yajun, Zhang Yongmin, et al. Development of monitoring detectors for fast pulse diode's running. Nuclear Electronics &Detection Technology, 2009, 29(2): 267-270 https://www.cnki.com.cn/Article/CJFDTOTAL-HERE200902008.htm [11] 卫兵, 傅贞, 王玉娟, 等. 脉冲功率装置中电容分压器的设计和应用[J]. 高电压技术, 2007, 33(12): 39-43. https://www.cnki.com.cn/Article/CJFDTOTAL-GDYJ200712011.htmWei Bing, Fu Zhen, Wang Yujuan, et al. Design and performance of capacitive divider for high-voltage pulse measurement. High Voltage Engineering, 2007, 33(12): 39-43 https://www.cnki.com.cn/Article/CJFDTOTAL-GDYJ200712011.htm [12] GJB6367-2008, 纳秒级分压器和电流线圈的方波标校方法[S].GJB6367-2008, Method of assignation and check by rectangular pulse injection for nanosecond voltage dividers and current measuring coils [13] 卫兵, 卿燕玲, 付佳斌, 等. 宽频带无源积分器的设计和实验[J]. 强激光与粒子束, 2011, 23 (4): 1108-1112. http://www.hplpb.com.cn/article/id/5179Wei Bing, Qing Yanling, , Fu Jiabin, et al. Design and performance of wideband coaxial passive integrator. High Power Laser and Particle Beams, 2011, 23 (4): 1108-1112 http://www.hplpb.com.cn/article/id/5179