Voltage transformer ferroresonance

Key Features
1) For the ferromagnetic resonance circuit, in the same loop power supply potential role may be more than a stable working condition. circuit breakers in the end what kind of

work in a stable condition caused by external shocks depends on the situation of the transition process.
2) PT is to produce the non-linear ferromagnetic properties of the root causes of ferromagnetic resonance, the saturation effect ferromagnetic element itself limits

the over Voltage stabilizer amplitude. Moreover return loss also damped resonance over-voltage and limitations. When the loop resistance is greater than a certain value, do not

Will be a strong ferromagnetic resonance over-voltage.
3) series resonant circuits, generate magnetic resonance voltage is a necessary condition ω0 = 1/L0C <; ω. Therefore, ferromagnetic resonance can occur within a

large range.
4) maintain and satisfaction resonant oscillation circuit resistance energy loss by frequency power supply. Frequency of the energy is converted into energy of another

resonant frequency, the conversion process must be periodic and a rhythm that ... 1/2 (1,2,3 ...) times the frequency of resonance.
5) damage to the PT ferromagnetic resonance. Magnetic resonance (divide) should generally have the following three conditions.
① ferromagnetic voltage transformer (PT) nonlinear effect is to produce the main ferromagnetic resonance.
② PT capacitive reactance is 100 times less than that match the parameters in the resonant range.
③ must excitation conditions, such as PT sudden closing, single-phase ground suddenly disappeared, outside interference on the system or systems operating over

voltage generated.
According to tests the resonant frequency of the current is more than 240 times the nominal current, the frequency of the resonant current is the normal current of

about 40 to 60 times, high-frequency resonance current is smaller. In these resonance, the resonant frequency of the destruction of the largest, if PT is well

insulated, frequency and high frequency are generally not

Compromise the safety of the device, and 6kV system has the above conditions.