1) breaking DC-component
开断直流分量
2) DC interruption
直流开断
1.
This paper performs an analysis on the essential question——DC interruption,and summarizes most of the interrupting methods used by DC circuit breaker.
对直流断路器研制的关键问题——直流开断进行了分析,综述了直流断路器采用的典型开断方法,并对实际系统中比较有代表性的3种直流断路器进行了介绍。
3) DC component
直流分量
1.
Effects of water trees on insulation resistance and DC component of XLPE cable;
水树对XLPE电缆绝缘电阻与直流分量的影响
2.
It includes two parts: (A) the transient recovery voltages after circuit breakers interrupt the short-circuit currents or the current is out of phase condition;(B) the time constant of DC component of short-circuit currents and current-zero offset.
结合1000kV特高压试验示范工程及规划的中国特高压电网,研究了交流1100kV断路器瞬态问题中的短路电流直流分量衰减时间常数及交流电流过零点的漂移现象,在此基础上提出了我国交流1100kV特高压断路器的工作条件建议,如特髙压断路器试验的短路电流直流分量衰减的时间常数等。
3.
In the light of the DC components existing in active filters(APFs) based on one-cycle control(OCC), the OCC and its various improvement approaches are presented.
针对基于单周控制的有源电力滤波器存在的直流分量问题,介绍了单周控制及其各种改进方法,说明了引入纹波法、双环控制、双向互补策略、单极调制和双边积分控制在单相有源电力滤波器中的应用情况,并根据级数收敛判据对上述单周控制策略的稳定性进行分析比较。
4) DC components
直流分量
1.
A new algorithm for blind watermarking based on DC components of DCT;
一种基于DCT域直流分量的盲水印算法
2.
The algorithm selects adaptively the embedding intensity to embed the watermark bits by modifying some AC components and DC components via the human visual system model and local characteristics of image,synthetically making use of the advantage of the AC components and DC components.
该算法利用视觉系统HVS特性和图像的局部特点,自适应地选择嵌入强度对载体图像各个分块的部分低频系数和直流系数嵌入水印,综合了交流分量和直流分量的嵌入优势,使水印的稳健性和不可见性达到较好的平衡。
5) DC off-set
直流分量
1.
The analysis of the whole region stability condition and the mechanism of the DC off-set in the compensated current of the system is proposed.
分析了系统的全局稳定条件和补偿后电流中直流分量的产生机理,研究了系统带不平衡负载和动、稳态补偿性能以及稳定性。
2.
There are DC off-sets in the compensated source current of the APF with one-cycle control under bipolar modulation.
采用双极调制方式单周控制APF补偿后的电源电流中存在直流分量。
3.
There are DC off-sets in the compensated source current of the traditional APF with one-cycle control due to the existent ripple and the peak current detection.
传统的单周期控制有源电力滤波器以峰值电流检测的控制方式和纹波电流的存在导致补偿后的电源电流中含有直流分量。
6) direct current component
直流分量
1.
A protection algorithm can be judged as having strong capability of anti-interference if it can eliminate decaying direct current component and high harmonic whose frequency is not the integer times of system base-frequency.
能否滤除非系统频率整数倍的谐波和衰减的直流分量是衡量保护算法抗干扰能力的重要特征。
2.
The article analyses the transient state of the unbalanced three-phase circuit on industial frequency and puts forward the concept that there are two direct current components with different attenuation coefficients.
分析了三相工频不平衡电路的暂态过程,提出了电流的直流分量中存在两个衰减系数不同的直流分量的概念。
补充资料:电力系统开断电感负载过电压
电力系统开断电感负载过电压
inductance switching-off overvoltage in electric power system
d一onl一x一tong kolduond旧ngan fuzo一guod旧nyo电力系统开断电感负载过电压(inductanceswitehing一off overvoltage in electrie powersystem)开断电感负载时由于电流在自然过零之前被强制截断导致瞬态振荡所引起的过电压。电感负载可以是空载和轻载变压器、并联电挽器和电动机等。 开断电感负载过电压的机理如图所示:电感电流i(t)在10处被截断,截流瞬间,电感负载L中储有磁场能LI02/2,负载杂散电容C中储有电场能CUoZ/2,截流后,这些能量将在LC回路中振荡,在全部能量转化为电场能的瞬间,电容上电压(即电感负载两端的电压)将达最大值u。一刃万不不Z夕万。如果电流在幅值I二处被截断,则过电压可达um二I,丫Z万。丫Z夕万为电感负载的特征阻抗。开断感性负载时的过电压(a)等值电路;(b)波形示意 开断电感负载过电压的幅值与负载的特性、断路器的截流能力有关。电感负载的杂散电容C值一般很小,特征阻抗很大,所以过电压有较高的值。断路器截流能力愈强,过电压幅值越高。如有的真空断路器在合闸电感负载时,由于过流保护动作将较大的激磁涌流截断,引起很高的过电压而将断路器损坏。由于断路器灭弧过程的分散性,开断电感负载的过电压具有统计性。 限制开断电感负载过电压的措施有:减小电感线圈的励磁电流(例如采用冷轧矽钢片),增大与电感并联的电容C(例如在变压器中采用纠结式绕组),可降低开断电感负载过电压。开断电感负载过电压的最大能量为众mZ/2,其绝对值不大,可用为防止雷电过电压的进雷器加以限制。
说明:补充资料仅用于学习参考,请勿用于其它任何用途。
参考词条