Ideal and practical voltage sources are two concepts commonly used in electrical engineering to describe the behavior of voltage sources in electronic circuits. They represent different levels of abstraction and realism when modeling real-world components.
Ideal Voltage Source:
An ideal voltage source is a theoretical concept used to simplify circuit analysis. It is assumed to provide a constant voltage across its terminals regardless of the current flowing through it or any other external conditions. In other words, an ideal voltage source maintains a fixed voltage output regardless of the load connected to it or the amount of current it needs to deliver. This simplification is useful for mathematical calculations and understanding basic circuit principles.
Key characteristics of an ideal voltage source:
Voltage remains constant regardless of the connected load.
It can provide any amount of current required by the load.
It has zero internal resistance.
It is not affected by changes in temperature, aging, or other real-world factors.
Practical Voltage Source:
A practical voltage source is a more realistic representation of a voltage source found in real-world applications. It takes into account the limitations and imperfections of actual devices. Practical voltage sources have internal resistance and are affected by factors such as load current, temperature, and aging.
Key characteristics of a practical voltage source:
Voltage drops under load: When a load is connected, the voltage across the terminals of the source may drop due to its internal resistance.
Limited current capability: A practical source has a maximum current it can provide before its voltage output starts to drop significantly.
Temperature effects: Temperature changes can influence the source's voltage output.
Aging and degradation: Over time, the source's voltage output might decrease due to component aging or wear.
In summary, the main difference between ideal and practical voltage sources lies in their level of abstraction and realism. Ideal voltage sources are theoretical constructs that provide a constant voltage regardless of any external conditions, making circuit analysis easier. Practical voltage sources, on the other hand, consider real-world factors like internal resistance, load effects, temperature, and aging, providing a more accurate representation of how voltage sources behave in actual circuits.