不平衡电流
- 网络Unbalanced current;Current Imbalance;Iunb
-
外部短路时,由于电流互感器(CT)饱和所引起的暂态不平衡电流造成的变压器差动保护误动作,一直是变压器差动保护中的一大技术难题。
The misoperation of transformer differential protection caused by transient unbalanced current resulted from saturation of CT is still a difficult technical problem .
-
但是使用高阻继电器时,CT的励磁电流降低了保护的灵敏度,所以低阻继电器又重新被启用,但必须从外部引入闭锁信号或启动信号或延时,以便避越外部故障的不平衡电流。
Now the low resistance relay is used for sensitivity in the resistance earth transformer . It is necessary to use blocking signals to overcome the imbalance current .
-
变压器励磁涌流和电流互感器(TA)饱和产生的不平衡电流是引起差动保护误动的两大因素。
Unbalanced currents generated by transformer inrush current and current transformer ( TA ) saturation are two major factors .
-
3DSVPWM技术合理利用两个零矢量对输出的影响,解决了三相四线制系统中的中线电流问题,实现了对不平衡电流的补偿。
The 3D-SVPWM technique solves the problem of the neutral line current by this influence and realizes the compensation for the imbalance , harmonic and neutral currents .
-
山东电网部分500kV线路不平衡电流偏大的原因分析及改善措施
Analysis on Oversize Unbalanced Currents in Part of 500 kV Transmission Lines of Shandong Power Grid and Corresponding Improvement Measures
-
结果表明,本文所提出的装置采用TTA(基于时域变换)算法,不但具有良好的谐波补偿能力,并且还能补偿无功和抑制不平衡电流和中线电流。
The results show that the device based on TTA ( Time-domain based Transform Algorithm ) has the perfect performance in that it not only decreases largely THD but also compensates effectively the reactive and imbalance current .
-
ip-iq法容易与对称分量法结合,共同分析不平衡电流问题。然后,设计波动滤除环节,解决短网电流存在的电流幅值波动问题。
The ip-iq method is easily combined with symmetrical component method to analysis the problem of the unbalanced current detection . Furthermore , we design filter-link to resolve the problem amplitude fluctuation of the short-net .
-
用原边相电流构成阻抗匹配平衡变压器的差动保护,当阻抗匹配系数KZ≠3+1时产生固有的不平衡电流,易引起误动作。
If impedance matching coefficient K_Z ≠ 3 + 1 for an impedance-matching balance transformer with differential protection based on phase current on primary side , there is inherent differential current , and may result in mal-operation .
-
直流助磁特性能使BCH-2型差动继电器可靠地躲过外部短路时暂态不平衡电流的非周期分量及变压器空载投入时的励磁涌流,从而有效避免保护装置的误动作。
The DC additional magnetic features can make the BCH-2 model differential relay to avoid reliably from the exciting surge produced by non-cycle component of transient unbalanced current under external short-circuit and put-in of idle transformer in order to prevent the protective device from maloperation .
-
调整不平衡电流并补偿功率因数的新型节能设备
New energy-saving equipments for adjusting unbalanced currents and compensating power factor
-
高压直流极母线差动保护不平衡电流分析
Analysis on the Unbalance Current of HVDC Pole Bus Differential Protection
-
主变差动保护不平衡电流产生及应对措施
Unbalanced Current Generated in Differential Protection of Main Transformer and Its Countermeasure
-
转子偏心对凸极同步发电机主保护不平衡电流的影响
Effects of Rotor Eccentricity on Unbalanced Current of Salient-pole Synchronous Generator Main Protection
-
浅析串联补偿电容装置不平衡电流的测试
Measurement for Unbalanced Current of Series Capacitor Compensation Equipment
-
一种具有不平衡电流保护功能的电流互感器
A kind of Current Transformer with Unbalance Current Protection
-
江陵换流站高压电容器组不平衡电流调整试验
The Adjustment Test for Unbalance Current of HV Capacitor Banks in Jiangling Converter Station
-
不平衡电流对船舶应急发电机运行的影响
Affection of Asymmetric Current on Emergency Generator Operation
-
大容量电容器组桥差不平衡电流保护近似计算
Approximate Calculation of Unbalance Protection on Differential Current Bridge of Large Capacity Capacitor Bank
-
不平衡电流无功补偿方法的研究
Research on unbalanced reactive current compensation method
-
浅谈变压器差动保护中不平衡电流的产生原因和克服方法
Discussion on the Cause of Generation and Restraint Measures for Unbalanced Current in Differential Relay Protection
-
双星形中性点不平衡电流保护的公式推导与分析
The Deduction and Analysis of the Protection Formula of the Neutral Unbalanced Current in Double-star Connection
-
传统零差保护均使用高阻继电器,高阻继电器有很高的避越不平衡电流的能力。
Traditionally REF adopts a high resistance relay with very high ability for overcoming the imbalance current .
-
计算结果表明,转子偏心故障达到一定程度时,单元件横差不平衡电流会超过保护动作定值,引起单元件横差保护的动作。
The result shows single element transverse differential protection would operate when the eccentricity reach some extent .
-
在农网或城网民用低压供电系统中,三相间不平衡电流普遍存在。
Unbalanced throe phase currents widely exist in rural electric network and low-voltage power supply for urban buildings .
-
根据试验结果对不平衡电流偏大的电容器组各臂电容值进行了调整。
According to the test results the HV capacitor banks which the unbalance current is larger have been adjusted .
-
在实际调试送电后电容器组的不平衡电流均在允许范围内。
After the energization of station system commissioning , the unbalance current of all HV capacitor banks is within permitted .
-
为了克服这些缺陷,对电容器不平衡电流保护进行了改进方法的研究。
In order to overcome its disadvantages , a study of mended unbalanced current protection scheme for shunt capacitor is made .
-
由于直接选取不平衡电流作为特征信号,可方便地实现定子故障的在线监测;
Since the unbalanced stator currents are used as the fault signs , the stator faults can be conveniently detected on-line .
-
该模型具有捕获系统中的不平衡电流的能力,可以适用于配电网三相不平衡的情况。
This model which can be applied to three-phase unbalanced distribution system has the capacity of capturing unbalanced current in the system .
-
对于传统比率制动式电流差动保护,在外部短路时电流互感器深度饱和误差造成的不平衡电流,及当内部短路时可能存在的流出电流,均可能引起差动保护误动或拒动。
Traditional percentage restraint differential protections may result in malfunction and non-operation owing to unbalanced current of external faults and efflux currents of internal faults .