What are the conditions for the equivalent conversion between the actual voltage source and the actu

1) The internal resistance of the actual voltage source is numerically equal to the internal resistance of the actual current source;

2) The conversion relationship between the voltage us of the actual voltage source and the current is of the actual current source is: us=isrs

On the equivalent transformation of the power supply model diagram, the "+" polarity of the constant voltage source us corresponds to the outflow direction of the constant current source IS.

There are also two equivalent transformations of the power supply model, which are equivalent to circuits other than their ports, but not for cases where the quantity to be sought is inside its port, i.e., "externally equivalent, internally non-equivalent".

The internal resistance of the current source is not infinity, and the internal resistance of the voltage source is not 0That is, the current source and the voltage source are not ideal power sources.

Equivalent transformation.

e0=is·rs

r0=rs or.

is=e0/r0

rs=r0.

From the above transformation formula, when rs= and e0 = infinity. When r0=0, is= . Therefore, the ideal power supply cannot be converted equivalently.

The ideal current source and the ideal voltage source cannot be converted equivalently. In addition, the equivalent conversion is only equivalent to the external circuit, not to the internal circuit of the power supply.

Equivalent conversion between voltage and current sources, which is often used in circuit analysis.

In the actual electronic application technology, I have done the actual voltage source, and I have also done the actual current source.

However, the equivalent conversion between the actual voltage source and the actual current source has never been heard of in my more than 40 years of experience.

In my opinion, the equivalent transformation is just a way to analyze the problem, and the actual voltage source is the voltage source, which can be designed as a current source, but it is not a current source itself.

<> solution: 12V voltage source series 3 resistors, equivalent to 12 3 = 4A current source, parallel 3 resistors, staring at the macro map.

3 resistors in parallel 6 resistors, the equivalent is: 3 6=2 resistors; 2 resistors in parallel 4A current source, equivalent to 2 4=8V voltage source, series 2 resistors, below:

Two 2 resistors are connected in series, equivalent to 4 resistors; 8V voltage source series 4 resistors, equivalent to 8 4 = 2A current source, parallel 4 resistors, below:

2A current source is connected to 5A current source in parallel, equivalent to 2+5=7A current source; 7A current source in parallel 4 resistors, equivalent to: 7 4 = 28V voltage source, series plexus call 4 resistors:

So: i=28 (4+2)=14 3(a).

It takes several transformations to have a result, and the excitement is carried out and seen, and the final macro has a clear fruit.

1.Conversion of the voltage source to an equivalent current chatter source: known:

us, rs, seeking: is, r's。Let r=rs ; is=us rs to find the equivalent current source.

Note: The flow direction of i should be consistent with the flow direction of u, and the internal current flow direction.

2.Conversion of the current source to an equivalent voltage source: Known:

is, rs, seeking: us, rs. Let r=rsus=is'rs can be found to find the equivalent voltage source.

Note: The internal current flow direction of the us should be consistent with the flow direction of the IS.

Equivalent transformation of the power supply.

Power supply is an indispensable and important part of any circuit, it is the first of the electrical energy in the circuit. The actual power sources include batteries, generators, signal sources, etc. Voltage sources and current sources are circuit models abstracted from the actual power supply.

Equivalent Transformation Steps:

1 Convert a voltage source equivalent to a current source or a current source to a voltage source.

2 Merge several parallel current sources (or voltage sources in series) into a single current source (or voltage source).

3 Apply the shunt formula (or partial pressure formula) to find the unknowns.

Precautions for the use of equivalent transformations

1. The equivalent conversion between the voltage source and the current source is only equivalent to the external circuit, and not to the internal circuit.

2. After the equivalent conversion of the voltage source and the current source, the polarity of the voltage source and the current source must be the same.

3. There can be no equivalent conversion between the ideal voltage source and the ideal current source.

Hope mine can help you.

Solution: This question is obviously asking you to find the left circuit.

The equivalent circuit of the Thevenin. Start by putting the 2A current source with.

Back 1 electrical resistor parallel is equivalent to a 2V voltage source in series with 1 resistor. Redraw.

Find the voltage UOC at both ends.

uoc=uab, when the current in the dry circuit is 0, the current flowing through the two 1 ohm resistors is 0. So the current in the left loop is.

12-6=(3+6)i, i.e. i=2 3 a, the direction is counterclockwise, so the voltage at both ends of the two parallel branches is.

12-6i=6+3i=8v。So uoc = 8-2 = 6v.

Find the req. The independent voltage source is short-circuited and the independent current source is disconnected. Yes, req=1+1+3*6 (3+6)=4 ohms.

So the left circuit is equivalent to a 6V voltage source connected in series with a 4 ohm resistor. There will be i=6 (4+2)=1a

The conditions are:

The internal resistance of the actual voltage source and the actual current source is RS;

If the parameters of the actual voltage source are us and rs are known, the parameters of the actual electricity and early current source are is=us rs and rs;

If the parameters of the actual current source are known to be is and RS, the parameters of the actual voltage source are us=isrs and RS.

An actual power supply, in terms of its external characteristics, can be regarded as both a voltage source and a current source. If it is regarded as a voltage source, it can be represented by a voltage source us and a resistor RS in series; If it is considered a current source, it can be represented by a current source is in parallel with a resistor RS. If they supply the same amount of current and terminal voltage to the same size load, the two power supplies are said to be equivalent, i.e., they have the same external characteristics.

The internal resistance of the current source is not infinity, and the internal resistance of the voltage source is not 0That is, the current source and the handshed make the voltage source not an ideal power source.

Equivalent transformation.

e0=is·rs

r0=rs or.

is=e0/r0

rs=r0.

From the above transformation formula, when rs= and e0 = infinity. When r0=0, is= . Therefore, the ideal power supply cannot be converted equivalently.

The ideal current source and the ideal voltage source cannot be converted equivalently. In addition, the equivalent conversion is only equivalent to the external circuit, not to the internal circuit of the power supply.

The internal resistance of the actual voltage source is numerically equal to the internal resistance of the actual current source;

The conversion relationship between the voltage us of the actual voltage source and the current is of the actual current source is: us=isrs

On the equivalent transformation of the power supply model diagram, the "+" polarity of the constant voltage source us corresponds to the outflow direction of the constant current source IS.

There are also two equivalent transformations of the power supply model, which are equivalent to circuits other than their ports, but not for cases where the quantity to be sought is inside its port, i.e., "externally equivalent, internally non-equivalent".

As shown in the figure below, the equivalent transformation of the collision search condition is calculated to be a good transformation: friend quarrel.