1) 3-harmonic
3次谐波
1.
Estimation of the 3-harmonic from Distortion Electromotive Forces in Auto Alternators;
汽车发电机电动势3次谐波分量的估算
2) third harmonic voltage
3次谐波电压
1.
By analyzing, the fault transient component of third harmonic voltage at neutral is approximately equal to that at terminal.
该保护方案根据单相接地故障后机端和中性点 3次谐波电压的故障暂态分量近似相同的特点 ,把两个故障分量的相量和与相量差分别作为保护动作信号及制动信号 ,通过比较数据窗内相应信号的谱能量检测定子单相接地故障。
2.
The features of transient components of zero-sequence voltage and the third harmonic voltages at generator terminal and at neutral are analyzed.
分析了发电机机端和中性点的零序基波及3次谐波电压故障暂态分量的特点,在此基础上提出了发电机定子绕组单相接地保护的自适应判据。
3) the third harmonic sensing scheme
3次谐波检测法
4) third-harmonic conversion
3次谐波转换
1.
In order to achieve stable and high conversion efficiency,the influence of fundamental pulse shape on third-harmonic generation was analyzed and different physical insights of third-harmonic conversion with flat-top pulse and Gaussian pulse were studied respectively.
为了使谐波转换系统保持高效稳定的3次谐波转换,采用数值模拟的方法,研究了基频光脉冲波形对3倍频转换效率的影响,并对高斯脉冲和平顶脉冲的不同谐波转换特点作了详细分析。
5) 1/3 sub-harmonic resonance
1/3次谐波共振
6) third harmonic injected SPWM
3次谐波注入SPWM
1.
For HVDC transmission system based on two-level voltage source converter(VSC),in order to decrease switching frequency and improve transient control ability as possible while the two-level VSC attains better harmonic characteristic,in this paper a hybrid PWM technology that combines selective harmonic elimination pulse width modulation(SHEPWM) with third harmonic injected SPWM is proposed.
针对基于两电平电压源换流器(voltage source converter,VSC)的HVDC系统,为实现两电平VSC在获得较优谐波特性的同时,尽可能降低开关频率、提高暂态控制能力,文中提出一种将特定次谐波消除脉宽调制(selective harmonic elimination pulse width modulation,SHEPWM)与3次谐波注入SPWM相结合的混合脉宽调制技术。
补充资料：电力牵引高次谐波
电力牵引高次谐波
harmonics of electric traction
d Ionl一qlony旧gooe}x{ebo电j]牵引高次谐波(harmonies of eleetrietraction)整流式交流电力机车在整流过程中将引起交流侧电流、电压波形畸变，按傅立叶级数分析该畸变波形可分解成频率为基波频率整数倍的一系列高次谐波分量的叠加。 高次谐波电流、电压可引起下列不良影响: (1)对通信线产生杂音干扰影响; (2)引起电力系统中其他电力电容器设备的过负荷; (3)当电气化铁路负荷某次谐波电流频率与电力系统自身谐振频率相近时，可产生电流谐振，使该次谐波电流在电力系统中放大，危及电力系统安全运行; (4)使旋转电机、变压器、电力电缆的出力减少并产生过热，影响电气设备寿命; (5)造成继电保护误动或仪表读数误差; (6)使半导体开关元件换相失灵。 为限制谙波的危害，各国都规定了允许谐波含量的标准(见供电质童)。 为降低电力牵引负荷产生的谐波，在电力牵引变电所和电力机车中可装设由电容、电感组成的谐波吸收装置。交流一直流一交流电力机车利用电力电子技术，可实现低谐波分量的负荷特性，使谐波含量降低。
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