Техническая информация

Reducing the risk of failure on high voltage instrument transformers in the transmission system using the application of narrowband dielectric frequency response (NB DFR) on HV CVTs.

This is an easy solution to measure the impedance values for cables, the values are used for calculation of compensation factor in distance protection.The compensation factor is first theoretically calculated and these values can now be compared with the measured values.

The test and maintenance of electrical components on rolling stock is not an easy job to do. Some maintainers dismount some of the parts and bring them to a central location for revision and maintenance. This is a cumbersome and time consuming exercise. In many cases, the electrical parts are replaced only when they break down and are not subject to periodical testing. This of course holds a risk as some parts, e.g. circuit breakers, are crucial for safety reasons.

The Power Grid Corporation of India Limited (PGCIL) is an Indian state-owned company headquartered in Gurugram (North India) engaged mainly in Trans-mission  of  Power  and  transmits  about  50%  of  the  total  power  generated  in  India  on  its  transmission  network.  The  company  owns  and  operates  about  1,61,790  circuit  kms  of  transmission  lines  at  800/765 kV,  400 kV,  220 kV  &  132 kV EHVAC and +500 kV HVDC levels and 248 sub-stations. Also, it has the transformation capacity of about 396 825 MVA as of 30th November 2019.

Transformer equipment manufacturers (OEMs) have a critical need to measure true ratio, as they must confirm proper manufacture of their transformers during construction and final assembly. Improper construction has consequences of higher cost, late delivery, and poor quality. The ability of a ratio instrument to be used for all steps involved makes it a practical valueto OEMs because only one instrument is purchased and used throughout each stage. Only the most reliable and accurate instruments make it to the factory floor. Winding stack under constructionre used: Art Mandigo Winding Service.

Safety warnings for DLRO2

Completing turns ratio tests on all transformer taps can be a cumbersome process. With One Touch OLTC from the TTRU3, anyone can configure and test all taps within a few short minutes.

REQUIREMENTS FOR SAFE WORK ENVIRONMENT WHEN PERFORMING MV or LV POWER CABLE FAULT LOCATING BY DISCHARGING A HIGH VOLTAGE CAPACITOR.

Since the 1950’s vacuum has been used as insulation media in switchgears. Even though that technology has proven to be very reliable, over time air will leak into the vacuum chamber and degrade the insulation. Also, a good practice is to measure after transport or accidents. The accepted way to test the vacuum integrity has always been through a voltage withstand test. For field tests DC test is preferred due to the weight andsize of the instruments.

The is capable of performing turns ratio tests on any phase shifting transformer by allow-ing for phase shifts to be entered with respect to the secondary winding. But with all of the differ-ent ways phase shift is expressed, how do you know if the entered phase shift value is correct?