Transformers: Types, Applications, and Measurement Techniques
Why are the grounded side of the transformers?
A: It gets to the secondary grounding that will preclude any dangerous situation in case of a discharge from primary to secondary.
Why not be shorted transformer secondary Measurement of tension?
A: Because currents circulate very intense that may damage the transformer. So when disassembling the measuring instrument should not be shorting the secondary of voltage transformer unit.
What is used transformers?
A: For that high-voltage networks isolate the high voltages to equipment Measure and reduce high voltages and intensities measured values easy measure.
What is called short-circuit voltage?
A: The short circuit voltage is that that applied to the primary causes circulation by this intensity transformer rated Secondary shorted.
How do I get the Short-circuiting the voltage processors is high?
A: Available 2 windings so that only part of the secondary flow skip to primary reactance increase induction of both windings and thereby will also increase the impedance transformer internal and tension will short circuit a high value.
How the output voltage varies of a transformer when loaded with a: Resistor, Capacitor, Coil?
R: Loaded with a capacitor: Increase the output voltage
Loaded with a Resistance: Decreases output voltage
Loaded with a roll: The tension decreases.
Explain 3 types of cooling that can be applied to transformers.
A: / / / / Natural: ambient air
/////// Forced air: a fan impels the air over the processor
/ / / / Natural and oil circulation: oil is pumped through the cooling elements, which cooled by a stream natural air.
/ / / / Forced air and movement oil: oil is pumped through refrigerators elements are cooled by air.
/////// For water and oil circulation: Oil is pumped through the cooling elements, which are r EFRIGERATORS with water.
What is called magnetization current?
A: It is that part of the current in vacuum gives rise to losses in the iron, manifested as heat. Current is generated in the surface of the conductor.
How to determine the polarity of a transformer?
A: To determine the polarity transformer, place a bridge between terminals left side of the transformer and a voltmeter is placed between the terminals on the right side of it, then feed the primary winding with a voltage value (V). View diagram.
If the voltmeter reading is greater that the transformer is additive Vx or if under the transformer is subtractive.
Single Phase Transformers
A single-phase transformer is
> Consists of two coils, the primary and secondary, without electrical contact between them and windings on an iron core
The Powers which is measured transformer in the vacuum is due losses due to magnetization (losses in iron)
Transformer short circuit voltages
Transfer / / short circuit voltage in%
Transfer measurement voltage / / less than 1
Transfer phase / / 4 … .10
Transfer type insulator / / 10
Transfer to toys / / 20
Transfer to ringers / / 40
Transfer experimental (plug) / / 70
Transfer on / / 100
The intensity of the current short-circuit regime depends voltage and short circuit internal impedance Transformer.
If you have the two windings so that the secondary field could object to the primary, the transformer submit a low internal impedance and also a small voltage shorted.
The Party of magnetic flux only through one of the windings is called leakage flux.
When loading a transformer with a resistor or reactance inductive output voltage decreases.
When loading a transformer with a capacitive reactance increases output voltage.
Transformers Voltage measurement
The terminals of the transformer voltage measurements are characterized with U and V (IM) YUYV (secondary). Transformers measure operating voltage virtually an open circuit.
For losses that are less potential windings are wound top of each other.
Transformers Intensity measure
These transformers have a low internal impedance measuring instruments and virtually shorted secondary. As the intensities flows are inversely proportional to the number of turns, far downstream intensity have a primary comprising a single or a few turns.
As in normal far downstream intensity function in short circuit current secondary will result in an influx opposite to the magnetic primary.
Measuring transformers intensity can not hold a protected side overcurrent. Moreover, when removing the instrument measurement must short-circuiting the output terminals
Transformer step to measure intensity.
Caliper for measuring transformer intensity.
PHASE TRANSFORMERS
The three-phase transformers serving to transform alternating voltages triphasic.
Stuff that has a processor distribution phase, rated power:
- High-voltage terminals
- Low Voltage terminals
- Investor
- Boiler Cover
- Nucleus of three columns
- High separate coils of aluminum
- Diecast frame
- Bands winding down Aluminum
- Boiler wings folded (filled with liquid)
In the three-phase transformers >> Cores are often used 3 or 5 columns. In the latter the 3 columns major plants are the carrying windings. The 2 exterior columns serve to close the magnetic circuit.
The coils of both primary and secondary windings are usually top of each other in order to reduce losses and the stress of shunt is small. There several possible arrangements of windings.
The primary windings and the secondary can be connected star and triangle. Hence in a three-phase transformer different connections can be made. % 3