Review of field acceptance hipot & PD testing of medium voltage underground cables
There are some well-defined guides and standards regarding factory testing of medium voltage shielded cables in laboratories provided by IEEE, IEC, ANSI/ICEA, and CSA. These guides cover AC withstand and PD testing of XLPE and EPR cables and accessories, such as 50/60Hz AC Hipot and PD tests which are routinely conducted on every reel of cable produced at the factory. All terminations, splices, and separable connectors are tested with more or less the same test method using different test levels and timing.
Design of Triangle Loop Antenna for Partial Discharge Impulse Signal Detection
The objective of this study was to evaluate the performance of a triangle loop antenna to assess its use as a potential sensor in partial discharge (PD) impulse signals detection. PD impulse signals were measured over a frequency up to 100 MHz at 3 kV through Needle-Plate Electrode experiment. The experiment was conducted to create an artificial PD acting as a breakdown that causes insulation failure. Subsequently, the characteristic of PD impulse signals was captured by triangle loop antenna with variation of diameters and number of turns. The number of turns is up to three turns and diameters of triangle loop antenna intervals are 6 cm, 8 cm and 10 cm. Then, the Fast Fourier Transforms (FFT) analysis was carried out to measure the frequency bandwidth. The results revealed that an experimental frequency is 32.01 MHz. Then, it can be observed that the amplitude value of peak-to-peak voltage (Vpp) for three turns 10 cm diameter of triangle loop antenna higher than the amplitude value for one turn and two turns of triangle loop antennas.
A Study on Technology Embedded English Classes Using QR Codes
The development of information and technology has brought plenty of changes to the educational environment. The prevalence of smart phones is particularly playing a huge role in shaping learning methods. Smart phones provide the opportunity to scan QR codes, which can greatly ease access to information. Due to a high recognition speed, recognition rate, and restoration rate, they can be useful tools for English teachers to use in their class. In this study, we suggest using QR codes for writing and picture descriptions. Based on this study, more research should invest in Technology Embedded English teaching models to create better English classes for students.