Kopplungsgrads

Kopplungsgrad, or coupling degree, is a dimensionless measure of the strength of interaction between two subsystems or variables within a coupled system. The term appears in German-language engineering and physics literature and is used in various fields where two parts influence each other.

In general, a higher Kopplungsgrad indicates a stronger interaction, while a lower value suggests weaker coupling. The exact scale and interpretation depend on the context and the definition adopted in a given domain. Some formulations normalize the coupling between 0 and 1, whereas others may yield different ranges or even signs depending on how the interaction is quantified.

In mechanical engineering, the Kopplungsgrad between rotating masses or structural components can be assessed by how effectively energy or motion is transferred through a coupling element. A nearly rigid, ideal coupling yields a high degree near 1, whereas flexible or damped connections reduce the coupling degree and alter dynamic response.

In electrical engineering, the term is closely related to coupling coefficients used for transformers and coupled inductors. The electrical coupling coefficient, often denoted k, ranges from 0 (no coupling) to 1 (perfect coupling) and reflects how much magnetic flux links both windings. This coefficient influences power transfer and impedance characteristics.

In data analysis and control theory, Kopplungsgrad can be estimated from time series or state variables using normalized cross-correlation, coherence, or mutual information to capture linear or nonlinear dependencies between signals.

Calculation approaches are domain-specific. Practitioners select a definition that yields a normalized, comparable measure of interaction strength suitable for design, diagnosis, or control purposes. See also coupling coefficient, coherence, mutual information, and transfer efficiency.