Wiki article · Collection 02

Series Resonance

Engineering reference on Series Resonance for wireless power system design, integration, and deployment.

6 minArticle 05/16Resonant WPT

Series Resonance — educational diagram — Fig.: Educational diagram for “Series Resonance”.

In a series-resonant tank, L and C are in series with the load path. At the resonant frequency the reactances cancel and the impedance magnitude reaches a minimum set mainly by resistance. Driven by a voltage-source inverter, series resonance tends to produce a current that rises as the load resistance falls — a behavior designers use carefully with battery loads.

01Characteristics

Natural current peaking near resonance for a voltage-fed inverter.
Simple capacitor count on each side when used as pure series compensation.
Sensitive to shorted or very light loads depending on the full topology.
Often combined into hybrid networks (for example series primary + parallel secondary).

Series Resonance — supporting diagram — Fig.: Supporting illustration for “Series Resonance”.

02In wireless docks

Pure series–series (SS) compensation is a classic teaching topology and still appears in products. It offers strong power capability when k is reasonable, but gain and bifurcation behavior must be mapped across misalignment. Many industrial designs move to LCC or other hybrids for a flatter gain and easier inverter current shaping.