When a voltage source is connected in parallel with a current source, who provides the power?

The ideal voltage source, current source and resistance are connected in parallel.

, it should first be made clear that the magnitude and direction of the resistor r current are always locked by the voltage source e: il=e r, and the direction is top-down.

1. The current source is and the voltage source E are connected in parallel in the same direction, see Figure 1. Because we have defined the direction of the voltage source from the negative to the positive.

At this point, the current source is always working, and the voltage source is either working or charging, depending on the situation. According to the magnitude of IS and IL, the current direction is divided into the following three situations:

1. When IS2 and IS=IL, all the current of the current source IS flows to the resistor R, and the voltage source E does not provide current, as if standing by and watching. The power is provided separately by the current source;

3. When IS>IL, all the current of the current source is charged to the voltage source except for the resistance R, and the remaining part (IS-IL). In this case, the charging current of the voltage source E is (IS-IL). The power is provided separately by the current source, and the voltage source absorbs the power.

2. The current source is and the voltage source E are connected in reverse parallel, see Figure 2.

Because the current direction of the resistor R has been locked from the voltage source E to flow downward, although the current source current is has gone to the door of the resistor R, it cannot flow into it, and finally has no choice but to flow from the negative pole of the voltage source to the positive pole, which increases the burden of the voltage source. At this time, the working current of voltage source E is (IS+IL). The power is provided by the voltage source alone, and the current source absorbs the power.

In parallel in the same direction, the voltage source is the load and the current source provides the power;

In reverse parallel, the current source is the load and the voltage source provides the power.

The voltage source and the current source are connected in parallel, and the voltage remains unchanged, and the current increases; i=i1+i2+..

The series current of the voltage source and the current source remains unchanged, and the voltage increases; u=u1+u2+..

The so-called "open-circuit voltage" of the equivalent power supply theorem refers to: the voltage between A and B after the load RL is disconnected from the circuit; The so-called "source removal" refers to the assumption that the power supply in the active two-terminal network is removed (short circuit of the voltage source and open circuit of the balance current source).

For complex circuits, it is impossible to simplify the circuit by resistor series and parallel connection methods, so it is necessary to use the principles and theorems of the network to simplify it.

The equivalent power supply theorem is an important theorem for simplifying linear active two-terminal networks and analytical circuits. Any circuit with two terminals, regardless of its complexity, is called a two-terminal network; If a linear two-terminal network contains power inside, it is called a linear active two-terminal network ns.

The equivalent power supply theorem is expressed as follows: any linear active two-terminal network can always be replaced by an equivalent power model for its external circuitry. Because the power supply model is divided into two types: the voltage source model and the current source model, there are two equivalent power supply theorems, one is called Thevenin's theorem and the other is Norton's theorem.

The internal resistance of the voltage source is bai0, and the voltage is constant.

du, the output current of the current source is constant, the output voltage is uncertain, and the current source version of the current source version of the current is all flowed to the overvoltage source after the two are connected in parallel, and the overall external voltage remains unchanged, which is equivalent to the original voltage source.

An actual power supply, in terms of its external characteristics, can be seen as both a voltage source and a current source. If it is regarded as a voltage source, it can be expressed by the combination of an ideal voltage source ES and a conductance GO in parallel, and if the same amount of current and terminal voltage are supplied to a load of the same size, the two power supplies are said to be equivalent, that is, they have the same external characteristics.

The voltage source and the current source are connected in parallel, which is equivalent to one voltage source; The voltage source and the current source are connected in series, which is equivalent to a current source.

This is because, after the former is connected in parallel, the voltage at both ends is always equal to the voltage of the voltage source; In the latter, the current passing through the series part after series connection is equal to the current value of the current source.

Current source. The current source and the voltage source are non-correlated directions, the current source emits power, and the voltage source absorbs power.

Introduction to the terminology of voltage sources:

1. In circuit analysis, the power supply is generally given as a known condition to give the residual lead. In terms of its working characteristics, the power supply can be divided into independent power supply and controlled power supply.

2. If the current of a two-terminal element is constant, or varies according to a given time function, the two-terminal component is called an independent voltage source, referred to as a voltage source.

A voltage source with a constant voltage retention is called a constant voltage source or a DC voltage source. A voltage source in which the voltage changes over time is called a time-varying voltage source. A time-varying voltage source that periodically destroys over time and has an average value of zero works well and is called an AC voltage source.

4. The characteristic of an independent voltage source is that its terminal voltage is determined by its characteristics, and has nothing to do with the position of the voltage source in the circuit.

The current of an independent voltage source is related to the external circuit to which it is connected. It is determined by both its voltage and the external circuit. <>

When the current source is connected in parallel with the voltage source, their external effect is equivalent to ().

Correct Answer: Voltage source.

When the voltage source is connected in parallel with the current source, the equivalent circuit is the voltage source (the output current of the voltage source is infinite, and the positive current source has no effect on its output voltage); When the voltage source is connected in series with the current source, the equivalent circuit is the current source (the output voltage of the current source is infinite, and the voltage source has no effect on its output current). After the ideal voltage source is connected in series with the ideal current source, the ideal voltage source does not work, the impedance of the ideal current source is infinite, and the ideal voltage source is equivalent to no access; After the ideal voltage source is connected in parallel with the ideal current source, the ideal current source does not work, the impedance of the ideal voltage source is zero, and the current of the ideal current source is not transmitted to the external circuit.

Summary. The size of the equivalent voltage source connected in parallel between the current source and the voltage source can be calculated by the following formula: v=i*r, where v is the size of the equivalent voltage source, i is the current size of the current source, and r is the resistance of the parallel circuit.

This formula indicates that the equivalent voltage source depends on the size of the current source and the size of the resistance of the parallel circuit.

The size of the equivalent voltage source of the parallel connection of the current source and the voltage source can be calculated by the following formula: v=i*r, where v is the size of the equivalent voltage source, i is the size of the collapse current of the current source, and r is the resistance of the parallel circuit. This formula indicates that the difference between the equivalent circle voltage source depends on the size of the current source and the size of the resistance of the parallel circuit.

You've done a great job! Can you elaborate on that?

The size of the equivalent voltage source of the parallel connection of the current source and the voltage source can be calculated by the formula v=i*r, where v is the size of the equivalent voltage source, i is the current of the current source of the line change, and r is the size of the shunt power barrier resistance. The formula illustrates that the equivalent voltage source depends on the resistance of the current source and the parallel circuit.

The parallel connection of the voltage source and the current source can be equivalent to the original voltage source for the following reasons:

The internal resistance of the ideal voltage source is 0, and the internal resistance of the current source is infinite, so after the two are connected in parallel, the internal resistance is 0, which is equivalent to the voltage source is not connected to anything in parallel, and it is still the original voltage source. But in practice, this is not the case, both the voltage source and the current source have internal resistance.

A voltage source, or ideal voltage source, is a model abstracted from an actual power source that always maintains a certain voltage at its ends, regardless of the amount of current flowing. A voltage source has two basic properties: first, its terminal voltage value u or a certain time function u(t) is independent of the current flowing.

Second, the voltage source itself is determined, while the current flowing through it is arbitrary.

The current source, that is, the ideal current source, is a model abstracted from the actual power supply, and its end button can always provide a certain current to the outside regardless of the voltage at both ends, and the current source has two basic properties: first, the current it provides is a fixed value i or a certain time function i(t) and has nothing to do with the voltage at both ends. Second, the current source itself is current-determined, and the voltage across it is arbitrary.

Under the premise of associating the positive direction, if the power: p>0, it means that the component consumes electrical power, and the component is the absorbed power (load); p<0, the component emits electrical power and is used as a power source. As shown below:

Therefore, when the power supply is used as a load, p > do grind 0.

This can be remembered based on the annotation methods that are often used in circuits. If the resistor is definitely an energy-dissipating component in the circuit, its voltage and current generally adopt the correlated positive direction, and at this time: p>0.

For the voltage source, the current flows out from the "+" pole of the voltage source, and the non-correlated forward dismantling direction annotation method is generally adopted. If p>0 at this time, it means that the power supply emits power, and it is used as a power supply in the circuit.

After mastering the above two situations, you can compare the memory in this way to grasp the relationship between the (non-)correlated positive direction, the positive and negative power p, and the receiving (ejecting) power of the sucking car.