 Tellegen's theorem

Tellegen's theorem is a fundamental principle in network theory and electrical engineering, formulated by Bernard Tellegen in 1952. It is a powerful statement about the conservation of energy in electrical networks, which can be applied to both linear and nonlinear circuits. The theorem asserts that for any network of interconnected electrical components, the total power entering the network is equal to the total power leaving the network when considering all the elements simultaneously, assuming that they are in a balanced state.