2019 - transformer core multipoint earthing fault reasons
30 15:05:21 transformer iron core multipoint earthing transformer is one of the more common fault, according to the statistics, transformer core multipoint earthing faults account for 42% of transformer faults, this kind of minor fault cause local overheating, core core for the person that weigh cause local damage.
The transformer is the core of many electrical components to function properly, therefore, no matter what kind of transformer faults will cause attaches great importance to.
Here, let's see what kind of transformer core multipoint earthing brings harm: when the normal operation of the transformer, it is not allowed to core multipoint earthing.
Around for normal operation of transformer, the windings of alternating magnetic field, due to the effect of electromagnetic induction, between the high voltage winding and low voltage winding, low voltage winding and iron core, there are parasitic capacitance between core and shell, charged winding will through the parasitic capacitance coupling effect, make the core over the ground produces suspension point.
Because the iron core and other metal components do not equal with the distance of the winding, there is a potential difference between the components, when the potential difference between two points to breakdown in the insulation, then produce the spark discharge.
This discharge is intermittent, down for a long time have bad effects on transformer oil and solid insulation, in order to eliminate this kind of phenomenon, the core and shell, reliable, and make it with other potential, but when there are two core or other metal components or multipoint earthing, pick up location will form a closed loop, cause circulation, cause local overheating, lead to oil decomposition, insulation performance, serious when, can make the iron core silicon steel sheet burn out, a serious accident main transformer.
So what are the causes of transformer core multipoint earthing and?
1, neglect the core touch when installation shell, a touch.
2, wear core bolt steel seat cover is too long and short silicon steel sheet.
3, core insulation be affected with damp be affected with damp or damage, leading to a high iron core multipoint earthing resistance.
4, submersible pump bearing wear, produce metal powder, form the bridge road, from the bottom and the iron yoke multipoint earthing.
5, grounding piece of bad cause short circuit for processing technology and design.
6, multipoint earthing caused due to the attachment.
7, from the left in the metal foreign body inside the main transformer and core technology of adverse factors such as burr, rust and welding slag ground.
Thus, the causes of transformer core multipoint earthing is not single, therefore caused multipoint earthing fault in check need to probe, one by one, so to find the real cause of failure, and then suit the remedy to the case, effectively solve the problem.