共查询到16条相似文献,搜索用时 125 毫秒
1.
通过对高压交联聚乙烯绝缘电缆进行直流耐压、0.1Hz超低频耐压、工频谐振以及调频串联谐振耐压等试验方法的分析比较,指出直流耐压对交联聚乙烯电缆的危害;超低频试验能有效发现电缆的水树故障;串联谐振的等效性最好;调频揩振试验方法等效性较好,设备轻便,试品长度的范围几乎不受限制。针对高压交联聚乙烯绝缘电缆耐压试验方法提出了建议。 相似文献
2.
介绍电缆常用的试验方法,指出了交联聚乙烯(XLPE)电缆试验存在的主要问题,提出了0.1Hz超低频(SLF)耐压试验方法,给出了0.1Hz超低频(SLF)耐压试验的标准和规范。 相似文献
3.
4.
0.1Hz超低频正弦波耐压试验技术及应用 总被引:3,自引:2,他引:3
介绍了 0 1Hz超低频正弦波耐压试验及耐压测试设备。该设备不增加技术难度 ,重量轻 ,成本低 ,便于在介损测试、局放测试和现场故障定位等领域内应用。还介绍了IEEEP4 0 0 2 /D1标准的核心内容 ,可供现场屏蔽电缆系统的耐压、诊断试验参考 相似文献
5.
6.
7.
8.
高压电机定子绕组的超低频耐压试验与遥控 总被引:2,自引:0,他引:2
超低频0.1HZ交流耐压试验与工频交流耐压试验,当合理确定等价系数β后是完全等价的,超低频0.1HZ交流耐压试验,有设备容量小,灵巧方便,相对延长试品电机寿命并可代替直流耐压试验的优点,应大力推广。现介绍研制的超低频0.1HZ耐压试验装置,采用遥控的交流耐压试验,根本上解决了高压试验人员的安全。遥控应推广至高压试验与测量中。 相似文献
9.
10.
介绍了XLPE/PE电缆现场试验新方法--0.1Hz超低频电压试验的基本原理和测量技术,用它测量电缆tanδ可以敏感地检查电缆绝缘的整体缺陷。给出了XPLE电缆tanδ现场测量结果。 相似文献
11.
12.
High-voltage on-site tests of extruded insulation cables are necessary to check the quality of the installation of the system. The test voltage should simulate the stress under service conditions, and generate the same failure mechanism. With respect to an optimum design of test systems, a frequency range of 20 to 300 Hz, proposed in the latest IEC Draft for on-site testing of extruded insulation cables, seems to be reasonable. The test results on model cables can be used for real cables concerning the influence of the waveform on the breakdown voltage. The withstand voltage decreases with increasing frequency. The withstand voltage and the electrical breakdown field strength are very close together for frequencies between 20 Hz to 300 Hz. Mechanical defects, as well as water trees, reduce the breakdown voltage at 0.1 Hz more than at 20 to 300 Hz, but the absolute test voltage values are higher, and the breakdown mechanism is different compared with voltages of power frequency or adjacent frequencies. For on-site tests, frequency-tuned resonant test systems (ACRF) can be recommended because they have a very good weight-to-test power ratio, and very low power demands 相似文献
13.
14.
Partial discharge (PD) degradation phenomena is one of the most important factors to decide the performance and the lifetime of the high voltage apparatus. During PD degradation tests of an epoxy specimen with an internal void, PD often change to a large number of very small PD known as swarming pulsive microdischarges (SPMD). Because the appearance of SPMD is concerned with the degradation of the insulating materials, the insulation diagnosis with the detection of SPMD becomes possible. However, SPMD cannot be detected with the conventional PD Detector because the PD magnitude of SPMD is too small. The computer-aided partial discharge analyzing system (CAPDAS) has been developed to detect and analyze the SPMD. Furthermore, a new PD parameter, the SPMD ratio has been introduced for quantitative analysis of SPMD. In this paper, the time variation of SPMD characteristics of a CIGRE Method-II specimen are investigated by using the CAPDAS. Further, the effect of the frequency of the applied voltage on SPMD is also investigated at 60 Hz and a very low frequency of 0.1 Hz. As a result, the comparison of PD magnitudes measured at 60 Hz with those at 0.1 Hz enables a quantitative analysis of SPMD characteristics to be possible by using only the conventional PD detector. 相似文献
15.
Eager G.S. Katz C. Fryszczyn B. Densley J. Bernstein B.S. 《Power Delivery, IEEE Transactions on》1997,12(2):565-570
This publication describes a laboratory test program conducted with the objective to develop a test that would replace the existing DC withstand test. The article describes the methodology used to establish the voltage duration and magnitude of VLF (0.1 Hz) high voltage field tests suitable for crosslinked polyethylene (XLPE) insulated power cable. The results show that the voltage breakdown of laboratory aged XLPE cable at 0.1 Hz is approximately equal to that at 60 Hz, that proof tests at 0.1 Hz cause very little damage to the cable, and that 0.1 Hz testing appears to be a satisfactory alternate to DC testing. Preliminary values are suggested for voltage magnitude and time duration of cable acceptance, maintenance and proof tests at 0.1 Hz for XLPE cable rated up to 35 kV. A program is underway to similarly evaluate samples of service-aged XLPE cable; as well as to demonstrate the use of the preliminary test values at typical utility installations 相似文献
16.
VLF电压试验电压(UT)和试验时间(tT)的选取直接影响到有效地发现绝缘缺陷的概率,但目前电力电缆线路VLF电压试验时如何选取UT和tT仍无明确结论。1980年以来各国标准规定值差异很大,试验的有效性和等效性尚在探讨之中,目前一般取UT=2~3.5U0(U0为相电压),tT=15~60 min。长期积累的运行经验和理论及试验研究证实,延长tT和提高UT将对电缆介质造成不可逆损害,导致介质早期击穿。因此结合国内外现场和试验室研究结果并采用数理统计分析的方法优选了VLF(0.1 Hz)UT和tT。结果表明:UT=3U0时,tT取40 min,基本能够满足电力电缆线路绝缘品质判别的现场试验要求。 相似文献