High Voltage
High voltage testing – Direct current (DC)
DC tests are used mainly to do “pressure tests” on high voltage cables. Although the cables operate with AC, AC testing is not practical. The high capacitance of the cables… Read more
Jun 01, 2013 | By Edvard Csanyi
High Voltage
Erection procedure for HV switchgear (Part 2)
Continued from first part: Erection procedure for HV switchgear (Part 1) Positioning of the cubicles should start near to the centre of the switchboard, installing as early as possible the… Read more
May 01, 2013 | By Edvard Csanyi
High Voltage
Erection procedure for HV switchgear (Part 1)
Before commencing erection of HV switchgear check that all connections are tight on busbars and on main circuits as well as auxiliary circuits. Examine the insulation very carefully, because there… Read more
Apr 29, 2013 | By Edvard Csanyi
High Voltage
Conductor Types Used For Overhead Lines
The international standards covering most conductor types for overhead lines are IEC 61089 (which supersedes IEC 207, 208, 209 and 210) and EN 50182 and 50183 (see Table 1). For… Read more
Apr 20, 2013 | By Edvard Csanyi
High Voltage
Using High-Speed Grounding Switches
Automatic high-speed grounding switches are applied for protection of power transformers when the cost of supplying other protective equipment is deemed unjustifiable and the amount of system disturbance that the… Read more
Feb 15, 2013 | By Edvard Csanyi
High Voltage
High Voltage Substations Overview (part 2)
Continued from first part: High Voltage Substations Overview (part 1) Transformers are used for the transformation of high and medium voltage to low voltage, flanked by specific protective devices and… Read more
Jan 26, 2013 | By Emmanouil Angeladas
High Voltage
High voltage substations overview (part 1)
High voltage substations are interconnection points within the power transmission and distribution systems between regions and countries. Different applications of substations lead to HV substations with and without power transformers: Step… Read more
Jan 25, 2013 | By Emmanouil Angeladas
Cables
Differences Between Earthed and Unearthed Cables
In HT electrical distribution, the system can be earthed or unearthed. The selection of unearthed or earthed cable depends on distribution system. If such system is earthed, then we have… Read more
Jan 21, 2013 | By jiguparmar
High Voltage
Purpose of Disconnect Switches In HV Substation
Switches may be of several types, the common characteristic is that none are designed to interrupt fault currents and the insulation or insulators associated with them must coordinate with the… Read more
Jan 14, 2013 | By Edvard Csanyi
High Voltage
Environmental Stresses On External Insulation
The external insulation (transmission line or substation) is exposed to electrical, mechanical, and environmental stresses. The applied voltage of an operating power system produces electrical stresses. The weather and the… Read more
Jan 07, 2013 | By Edvard Csanyi
High Voltage
7 Golden Safety Rules for Working In HV Laboratory
Employees performing operations and testing work in high voltage laboratory are exposed to a greater hazard than most other employees. Safety rules MUST NOT be seen as a means of limiting… Read more
Dec 26, 2012 | By Edvard Csanyi
High Voltage
Enhance Grid Reliability With Hybrid HVDC Breaker
Introduction to HHVDC How does Hybrid HVDC Breaker work? (VIDEO) Hybrid HVDC Breaker Construction Proactive control Prototype Design Of The Hybrid HVDC Breaker Comparison/Summary The advance of voltage source converter-based… Read more
Dec 15, 2012 | By Edvard Csanyi
High Voltage
Methods of Controlling Lightning Overvoltages in HV
For well shielded transmission lines, the backflashover condition, close to the substation, is of prime concern for determining the location and number of surge arresters required to achieve insulation coordination… Read more
Dec 08, 2012 | By Edvard Csanyi
High Voltage
HV Instrument Current Transformers in T&D
Electrical measurements on a high-voltage transmission and distribution systems cannot be made practically or safely with direct contact to the power carrying conductors. Instead, the voltages and currents must be… Read more
Nov 23, 2012 | By Edvard Csanyi
High Voltage
The Purpose of High Voltage Circuit Switchers
Circuit switchers have been developed to overcome some of the limitations of fusing for substation power transformers. Circuit switchers have SF6 gas interrupters and are designed to provide three-phase interruption… Read more
Nov 16, 2012 | By Edvard Csanyi
