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I am assuming that we are referring to an ordinary power transformer working at 50-60 Hz of alternating current circuit system. Saturation in these Transformers is the result of the magnetic field in the iron core reaching the saturation phase. At low current levels on the input side (currents are measured in amperes or amps) the magnetic filed produced in the core increases linearly with the current. Consequently, the current produced in the output coils is proportional to the input currents. If the amount of current in the input coil is large, the magnetic field in the core will not be a smooth sine wave, but a sine wave with tops and bottoms chopped as the magnetic core reaches saturation at the peak current level. This happens even if the input current remains a sine wave. The current induced in the output is directly proportional to the magnetic field and hence has the same shape - chopped off sine wave. Here are some of the implications:
1. Energy transfer from input to output is now limited by the chopping process which limits the peak current that can be induced into the output coil.
2. Energy transfer efficiency goes down - more energy may be poured in, but output energy does not increase significantly. Transformer will heat up as input coils experience greater currents. There will also be greater heating of the magnetic core due to magnetic hysteresis effects.
3. The output current has a chopped sine wave shape and hence has more 'harmonics' - waves with frequencies that are multiples of the input waves. The output current wave shape resembles a square wave more than the input sine wave. This is akin to waves produced by Electric Guitar distortion equipment. While this may not be important in some applications such as heating, it is usually unacceptable in audio transformers.
Wiki User
∙ 13y ago
Wiki User
∙ 12y agoSaturation describes the condition when a magnetic circuit (e.g. the core of the CT) reaches its maximum flux density (B). Any further increase in its magnetic field strength (H) will have no effect on the flux density. Since magnetic field strength is directly proportional to the current flowing through the primary winding, once saturation is reached, the CT's secondary current will no longer be proportional to the primary current.
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Why dc current cannot be used in transformers?
Transformer are passive devices thattransform AC to AC by magnetics and coupling. DC IS UNIDIRECTIONAL it does not change POLARITY. While it is possible to saturate a transformer primary it output cannot reflect the change since it has reached steady state
What will happen to frequency of current when voltage is changed using a step up or step down transformer?
Frequency does not change when you use a step-up or step-down transformer. Only current and voltage is changed.
What usually happens at consumer end when the current carrying capacity of transformer is exceeded?
What should happen is that the circuit-breaker should trip to cut off the current before the transformer becomes damaged by overheating.
What happen when 220v dc is applied to a 220v ac single phase transformer?
The current would rise until it blows the fuse or breaker and that would produce an arc as the transformer's inductance tries to maintain the current.
How is current controlled in welding transformer?
in welding machine, the transformer used is basically a current transforrmer. so by changing the tap of secondary side of transformer, we can increase or decrease the current in the transformer.
How you can find positive and negative in a transformer?
There is no positive and negative on a transformer. Transformers will only pass AC (alternating current), due to the fact that induction will only occur with a moving field. The current has to be changing polarity and intensity continuosly, for the current to be induced in the windings. Both terminals on the output vary, with relation to each other. Put DC into a transformer and the coils will saturate, overheat and probably burn out.
Why the output voltage from a transformer is zero if a direct current flows through the primary coil?
A transformer relies on AC current flowing through the primary to set up changing magnetic fields in the core. The field flows through the core and in to the secondary of the transformer, generating an AC current. The current must be AC, otherwise the magnetic field in the core of the transformer will saturate. In the same way, the armature of a dynamo or alternator must be moving in order to create a changing magnetic field to create current through the windings.
Why dc current cannot be used in transformers?
Transformer are passive devices thattransform AC to AC by magnetics and coupling. DC IS UNIDIRECTIONAL it does not change POLARITY. While it is possible to saturate a transformer primary it output cannot reflect the change since it has reached steady state
Can transformer be used 225 percent of capacity?
Yes, but not continuously and not for long. That transformer's core will saturate and get hot, possibly to the point of becoming a fire hazard.
What will happen to frequency of current when voltage is changed using a step up or step down transformer?
Frequency does not change when you use a step-up or step-down transformer. Only current and voltage is changed.
What usually happens at consumer end when the current carrying capacity of transformer is exceeded?
What should happen is that the circuit-breaker should trip to cut off the current before the transformer becomes damaged by overheating.
What will happen if you pass AC current through a transformer?
If the transformer was designed for the specific frequency in use, it will step up or down voltage and current as it was designed to do. Transformers transform how power "looks" by increasing and decreasing voltage and current, while keeping power output equivalent to input (if you ignore the transformer losses).
What is meant by transformer charging?
Most likely this is referring to the initial inrush that occurs when a transformer is energized. The core of a transformer is designed for a specific magnetic field strength; When a transformer is switched into a circuit, it usually will not be switched at exactly a voltage peak. When the voltage is at its' peak, the induced magnetic field will be at zero. If the switching occurs at a voltage zero, the magnetic field strength will attempt to climb to double the designed value; since the transformer core is not generally oversized to this degree, it will saturate. This causes large inflows of current to the transformer, and shows up as even harmonics (mainly second harmonics) in the current waveform. This settles out within a few seconds (generally) to a small energizing current, usually less than 1% of the transformer's rated current.
What happen when 220v dc is applied to a 220v ac single phase transformer?
The current would rise until it blows the fuse or breaker and that would produce an arc as the transformer's inductance tries to maintain the current.
How is current controlled in welding transformer?
in welding machine, the transformer used is basically a current transforrmer. so by changing the tap of secondary side of transformer, we can increase or decrease the current in the transformer.
What is principle of Current transformer?
why does have to short-circuit secondary wire of current transformer ?
What must happen to the electric current in power lines before it can safely enter your home?
step-down transformer
