Theveninlähde

Theveninlähde, often referred to as the Thevenin equivalent circuit, is a simplified representation of a complex linear electrical network. It allows engineers to analyze the behavior of a circuit from the perspective of a specific load connected to it. Thevenin's theorem states that any linear electrical network, viewed from two terminals, can be replaced by an equivalent circuit consisting of a single voltage source in series with a single impedance (or resistance in DC circuits).

The voltage source in the Thevenin equivalent circuit is known as the Thevenin voltage (Vth). It represents the open-circuit voltage measured across the terminals of the original network. The impedance is called the Thevenin impedance (Rth or Zth). It is calculated by turning off all independent sources within the original network (voltage sources become short circuits, and current sources become open circuits) and then finding the equivalent impedance seen looking into the terminals.

The advantage of using the Thevenin equivalent is that it significantly simplifies circuit analysis, especially when the behavior of the circuit with respect to varying loads needs to be determined. Instead of re-analyzing the entire complex network for each different load, one can simply connect the load to the much simpler Thevenin equivalent circuit. This principle is widely used in electronics and electrical engineering for simplifying circuit designs and troubleshooting.