Thursday, October 4, 2007

Partial discharge analysis prevents high voltage equipment failure

The partial discharge process occurs in electrical equipment submitted to high voltage stress. It represents the dielectric breakdown of an electrical insulation and usually has a sporadic character. Because partial discharge occurs randomly and unexpectedly, regular partial discharge analysis is highly recommended with any piece of high voltage equipment. The effects of the partial discharge phenomenon can be very grave and even lead to a complete breakdown. Timely detection can help you avoid very unpleasant situations. Find out more about avoiding the extremely hazardous effects of partial discharge, with the aid of partial discharge switchgear and other devices, at elec-di.com

The partial discharge process can be very hazardous to high voltage equipment. It usually starts within cracks, voids, bubbles in liquid dielectrics or enclosures within solid dielectrics. Partial discharge within insulating materials commences in the dielectric, within gas-filled voids. In this particular situation, the partial discharge phenomenon is the result of high voltage stress across the void. Partial discharge can sometimes be relatively harmless, but in most cases its effects are devastating. For instance, discharges which take place within polymeric cables are extremely hazardous. Once partial discharge begins, it progressively deteriorates the insulating materials up to the point where it causes a complete breakdown of the equipment. Partial discharge switchgear can help you escape the devastating consequences this process may have.

Once the partial discharge process commences there is a high probability that the high voltage equipment will end up failing entirely. If you want to avoid the destruction of your electrical equipment you should use partial discharge analysis and monitoring devices. Partial discharge can also be prevented through thorough design and careful material selection. Manufacturers should use partial discharge detectors in all of the production stages. Periodical check ups are also important when trying to avoid any unpleasant surprises. If you want to make sure your high voltage equipment will function perfectly on the long run, thorough partial discharge analysis is the only reliable solution.

There are several commonly used methods of accurately detecting partial discharge. For instance, a very widespread detection method is by using a calibrator. Partial discharge current flows are usually very brief and discharges take the form of random pulses. With the help of a calibrator, the intensity of the pulses is measured against the voltages obtained from a calibration unit and is then discharged onto a measuring device. Another frequent detection method is the so-called wideband detection. In this situation, the pairing impedance consists of a small Q parallel-resonant RLC circuit which leads to a decrease in the existing voltage and an amplification of the discharge generated voltage. Other partial discharge analysis and detection methods include field testing, laboratory testing, narrow band detection or differential discharge bridge methods.

The importance of preventing complete system failure as a consequence of partial discharge occurrences has been fully acknowledged at the beginning of the past century. Electrical discharges usually occur across a portion of insulation between two conducting electrodes and lead to the so-called partial discharge phenomenon. Once the process is triggered, it can have extremely destructive consequences if left undetected. The high voltage equipment may even completely fail after such an occurrence. Using partial discharge analysis methods and devices, such as partial discharge switchgear, can help you save a lot of time and money along the way. At elec-di.com you will find a full range of products such as partial discharge switchgear to help you avoid problematic situations.


http://www.articleco.com/Article/Partial-discharge-analysis-prevents-high-voltage-equipment-failure-/42608