The current flowing out of the positive electrode is the output power, and the current flowing into the positive electrode is the absorbed power.
The picture below: the voltage at the resistor terminal is 10V (negative on the left and positive on the right), and the voltage on the current source terminal is 15-10=5V (positive on the top and negative on the bottom).
At this time, the voltage source outputs power and the current source absorbs power (the current source terminal voltage is positive up and down).
Top left picture: The current flowing into the resistor (from the top) is 15/5=3A, so the current flowing out of the voltage source=3-2=1A, both the voltage source and the current source are output power (voltage The voltages at the source and current source terminals are both positive up and negative down, 15V).
The picture on the right: similar to the picture on the left, but because the direction of the current source is opposite, the current flowing out of the voltage source is 5A, the voltage source outputs power, and the current source absorbs power (the current source terminal voltage is 15V, the bottom is negative and the top is just).
Extended information:
The internal resistance of the current source is very large relative to the load impedance, and load impedance fluctuations will not change the current size. There is no point in adding a series resistor in the current source loop because it does not change the current flowing through the load, nor does it change the voltage across the load. This type of resistor should be simplified on the schematic diagram. The load impedance is meaningful only when connected in parallel to the current source, and has a shunt relationship with the internal resistance.
Due to various reasons such as internal resistance, the ideal current source does not exist in the real world, but such a model is very valuable for circuit analysis. In fact, if a current source does not fluctuate significantly when the voltage changes, we usually assume that it is an ideal current source.
The internal resistance of the voltage source is very small relative to the load impedance, and fluctuations in load impedance will not change the voltage level. It only makes sense to connect a resistor in series in the voltage source circuit. The resistor connected in parallel to the voltage source cannot change the current of the load, nor can it change the voltage on the load. This resistor is redundant on the schematic diagram and should be deleted. The load impedance is meaningful only if it is connected in series in the voltage source circuit, and has a voltage dividing relationship with the internal resistance.
The voltage source is an ideal component because it can provide a certain amount of energy to the external circuit, so it is also called an active component.
Within the allowable power range, voltage source strings of the same frequency can be equivalent to a voltage source of the same frequency
The terminal voltage of an ideal voltage source has nothing to do with its current. The voltage always remains a constant or a function of a given time.
Power refers to the amount of work done by an object in unit time, that is, power is a physical quantity that describes the speed of work. The amount of work is fixed, and the shorter the time, the greater the power value. The formula for finding power is power = work/time. Power is a physical quantity that represents the speed of work. The work done per unit time is called power, represented by P. Therefore, power is equal to the scalar product of the force and the velocity of the point on which the force is applied.
There are four methods for measuring power:
(1) Diode detection power method;
(2) Equivalent thermal power consumption detection method;
(3) True RMS/DC (TRMS/DC) conversion detection power method;
(4) Logarithmic amplification detection power method.
The characteristic curve of an ordinary logarithmic amplifier is only suitable for sine wave input signals. When the input signal is not a sine wave, the intercept on the characteristic curve will change, thus affecting the output voltage value. The output reading should be corrected at this time.
It should be pointed out that although the AD8362 single-chip RF true RMS power detector produced by ADI also belongs to the logarithmic detection power method, it can be applied to any input signal waveform by using unique patented technology. And the intercept on the characteristic curve does not change with the input signal.
Reference materials: Baidu Encyclopedia - Current Source? Baidu Encyclopedia - Voltage Source