Solving Series Transformers Problem with Lumped Resistance

In summary, the conversation discusses a problem with measured current not matching the expected turns ratio of two 50:5 nominal turn toroidal CTs. The person wonders if complex models or lumped wire resistance should be used to analyze the situation and suggests looking at the dot convention and transformer efficiency. They also mention the possibility of the two transformers behaving as one large transformer and the presence of a strong magnetic field in cheesy E-lams.
  • #1
MRKN
6
0
This is a problem I stumbled upon after noticing a pattern in the lab- the measured current was never quite what you'd expect from the turns ratio of either transformer alone, but somewhere in the middle.

I used 50:5 nominal turn toroidal CTs with 15 turns in one CT primary and 5 turns in the other primary.

This is not a homework question but rather an inquiry as far as whether or not I'd need to use complex models to analyze this situation, or rather lumped wire resistance.

To get a good start, notice the opposition of KVL in the secondary with the dot convention. This suggests zero flux in the transformer with the lesser amount of turns and thus simply Is = N1(Ip).
 

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  • #2
Cannot be answered without knowing transformer efficiency (function of frequency, windings, core material).

An average current would be expected if the two transformers were magnetically coupled and behaving as one large transformer. Cheesy E-lams at 50-60Hz have a huge field...
 
  • #3
you can find at basic electronic and tutorial..
 

Related to Solving Series Transformers Problem with Lumped Resistance

1. What is a series transformer?

A series transformer is a type of transformer where the primary and secondary windings are connected in series, as opposed to parallel. This allows for the voltage to be stepped up or down, depending on the turns ratio between the windings.

2. How do you solve a series transformer problem?

To solve a series transformer problem, you will need to use the formula Vp/Vs = Np/Ns, where Vp is the primary voltage, Vs is the secondary voltage, Np is the number of turns in the primary winding, and Ns is the number of turns in the secondary winding. You will also need to take into account the resistance of the windings and any external resistance in the circuit.

3. What is lumped resistance in a series transformer?

Lumped resistance refers to the total resistance in a circuit, including the resistance of the transformer windings and any external resistors in the circuit. It is important to consider this resistance when solving series transformer problems, as it affects the voltage output.

4. How does the turns ratio affect the output voltage in a series transformer?

The turns ratio, represented by Np/Ns, determines the relationship between the primary and secondary voltages in a series transformer. A higher turns ratio (more turns in the secondary winding) will result in a higher output voltage, while a lower turns ratio will result in a lower output voltage.

5. What are some common applications of series transformers?

Series transformers are commonly used in electronic devices, such as power supplies, to step up or step down voltage levels. They are also used in electrical transmission systems to adjust the voltage for efficient transmission over long distances.

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