Coupling between coils through shared flux, basis of transformers.
Two coils share flux linkage M=k√(L₁L₂), 0≤k≤1. Induced voltage in coil 2: v₂=M di₁/dt. Series aiding L=L₁+L₂+2M. Dot convention shows polarity. It is the basis of transformers and wireless charging.
Qi wireless chargers use coupled coils.
Mutual inductance is the coupling that transfers energy between coils without electrical contact, and it is the basis of transformers and wireless charging.
Coupling between coils through shared flux, basis of transformers.
Mutual inductance is the coupling that transfers energy between coils without electrical contact, and it is the basis of transformers and wireless charging.
It is a number between zero and one that measures how much of one coil's flux links the other. A value near one means tight coupling.
The sign depends on how the coils are wound and connected. Dot notation shows the polarity of the coupling.
Typical applications include estimating the coupling between two coils in a wireless charger, analysing crosstalk between two adjacent PCB traces and designing a current transformer for measuring high currents.
Study "Two-port networks" first (topic 49 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Coupling coefficient k. Leakage inductance. Resonant inductive coupling.
Qi wireless chargers use coupled coils.
The next topic is "Transformers", which builds directly on this one.
It is classed as Intermediate in Electrical Engineering (topic 50 of 106). It is an intermediate topic. Work through the beginner topics in Electrical Engineering first.
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