Transformers are widely used in power distribution systems to control and protect circuits. Due to the complexity of the transformer structure and the type of failure, it is difficult for maintenance personnel to determine the failure. In order to facilitate maintenance personnel to accurately determine the type of failure, the cause of the failure, and timely maintenance, shorten the failure time. The transformer manufacturer introduces several common faults for your reference.
(1) Rejection or failure
This kind of fault is an important fault of the transformer, and its causes can be divided into two categories. One type is caused by mechanical failure of the operating mechanism and transmission system. The specific performance is that the mechanism is stuck, the parts are deformed, displaced or damaged, the closed and closed core is loose, the clip is loose, the shaft pin is loose and the trip is abnormal. The other type is caused by electrical control and auxiliary circuits. It is characterized by poor secondary wiring contact, loose terminals, wrong wiring, burning of the closing and closing coils due to poor mechanism or switch, failure and operation of auxiliary switches. Power supply, closed contactor, micro switch, etc.
(2) Breaking fault
This type of failure is caused by the main body of the circuit breaker. For oil-free circuit breakers, the main performances are fuel injection short circuit, burnout of the arc extinguishing chamber, insufficient breaking capacity and explosion when closed. The vacuum circuit breaker is characterized by air leakage from the arc-extinguishing chamber and bellows, reduced vacuum, re-ignition of the capacitor bank and rupture of the ceramic tube.
(3) Poor insulation
Insulation class should correctly handle the relationship between various voltages (including working voltage and various overvoltages) acting on the insulation, various voltage limiting measures and dielectric strength. Make efforts to make products safe and economical, and obtain economic benefits. In the case of insulation failure, the main performances are external insulation flashover breakdown to ground, internal insulation flashover breakdown to phase, phase insulation flashover breakdown, lightning overvoltage flashover breakdown, porcelain shell, capacitor shell flashover, pollution Flashes, breakdowns, explosions, arcing of lifting rods, breakdowns, explosions, broken porcelain bottles.
(4) Current-carrying fault
The main reason for the current-carrying failure when the voltage is 72 ~ 12KV is that the contacts of the transformer isolation plug cause the contacts to melt.
(5) External force and other faults
Including foreign body impact, natural disaster, small animal short circuit and other unknown external forces and unexpected failures.