查询词典 neutral point

And then, a neutral-point balancing control method, which is based on the detecti...

实验结果验证了控制方案的正确性和可行性。

The traditional BLDCM mathematical model establishment in the electric motor two-phase breakover foundations, in fact the neutral point is hanging, inevitable existence three-phase breakover at the same time.

传统的直流无刷电机数学模型建立在电动机两两导通的基础上，而实际上由于电动机中性点悬空，不可避免存在三相同时导通的情况。

The resistance products have various types, and are for different lightning arrester, restrictive transformer, capacitor, electric machinery, vacuum switch, transformer neutral point sealed electrical instruments, cable, and railway line overvoltage.

本公司电阻片生产引进日立公司最新配方，工艺装备齐全、先进，采用全自动双向压制，四条窑炉烧制（排胶——预烧——烧成——热处理），侧面绝缘采用无机高阻层与有机绝缘漆相结合，检测设备齐全、准确，保证了电阻片具备优良的性能，各项指标明显优于GB11032标准。

Finally,this paper discusses the problems of neutral point control that exists in the three-level inverter, and adopts two methods to control neutral voltage balance namely judging power direction and detecting instantaneous current value.

最后论文还对多电平逆变器存在的中点电位漂移问题进行了讨论，并采用两种方法来实现中点电压平衡，即判别逆变器功率流向法和检测瞬时电流值方法。

When 10（20）kV electrical source side neutral point adopts low-resistance grounding system,the existing problems of the high-voltage equipment protective grounding and low-voltage neutral point system grounding divided network settings in the distribution substations are analyzed.

摘要对 10（20）kV电源侧中性点采用小电阻接地系统的配电变电所中，高压设备的保护接地和低压中性点系统接地分网设置存在的问题进行了分析。

Directly in the neutral point of the grounding of low voltage power supply system can be used by protective earth, and then use protection neutral line.

在中性点直接接地的低压供电系统中既可采用保护接地，也可采用保护接中性线。

Based on the analysis of the affected extent of the neutral-point potential by every space vector on all kinds of voltage and current conditions the concept named neutral point control grade was proposed for the first time in this paper. The calculation formulas of NPCG were presented as well. Based on NPCG, a novel modulation scheme called optimized 3D space vector modulation (O3DSVM) scheme was proposed in a-b-0 coordinates based on the translation principle of axes, by which the space vectors with higher NPCG values are selected to synthesize the object vector to suppress the unbalance of the neutral-point potential.

该文通过对各种电流电压状态下每个三维空间矢量对直流中点电位的影响进行分析，提出了"中点控制度"(neutral-point control grades，NPCG)的概念，并给出了NPCG的计算公式；基于NPCG，在a-b-0坐标系下提出一种基于坐标平移原理的新型"三维矢量优化选择调制策略"(optimized 3D space vector modulation，O3DSVM)，该调制策略能优化选择NPCG值较高的矢量以合成目标矢量，从而达到最大程度控制直流中点电位偏移的目的。

The neutral-point unbalancing problem is analyzed and the control strategy is proposed which can inhibit the neutral-point shift.

对多电平变流器中的中点电位不平衡机理进行分析，提出一种能有效抑制中点电位偏移的控制算法。

The selection of neutral-point earthing ways of the hydrogenerator of left-bank power station in the Three Gorges Project should be related to one-point earthing protection of the stator of its generator within one hundred percent framework.

三峡船闸高边坡，因地应力释放、渗流条件变化和岩石徐变，使岩坡产生缓慢位移，改变了人字门的支承条件，从而影响到人字门的正常工作。

With analysis on the control model, an improved automatic tuning method for arc-suppression coil is proposed, that is: adopting voltage feed forward control to restrain interfere of 50Hz displacement voltage, which can improve the characteristic of the injected signal significantly, make the injected signal without reference to unbalanced network and neutral displaced system. Another innovation is detecting the magnitude of neutral point signal-frequency voltage to judge the resonant state, which improves the sensitivity and accuracy of resonant judgement effectively.

基于对控制模型的分析，提出了一种新的注入变频信号的消弧线圈自动调谐方法：通过电压前馈校正控制的引入，有效抑制了50Hz工频电压对注入信号的干扰，使得注入信号不受电网不对称及中性点位移电压的影响；提出以中性点注入信号电压幅值最大做为新的谐振判据，有效提高了谐振状态判断的灵敏度和准确度。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。