Hybrid LC Filter
Encyclopedia
Hybrid LC filter is a kind of LC filter, which typically contains two conductive foil
layers, separated by an insulation material and coiled on a core. One layer, which is placed between the voltage source
, such as inverter
, and a load, is called “the main foil”; this layer forms filter inductance
. Another foil, called “the auxiliary foil”, is connected to a neutral potential (e.g. earth), forming the useful capacitance
between foils. This way the self-capacitance of the main foil is crucially decreased. Filter is characterized by improved high-frequency performance (working frequency range is at least up to tens of MHz). The mutual inductance between foil layers is rather high, coupling factor is typically about 0.95-0.99. Higher the mutual inductance provided, better the damping properties of the hybrid LC filter.
Foil
Foil may refer to:Materials* Foil , a quite thin sheet of metal, usually manufactured with a rolling mill machine* Metal leaf, a very thin sheet of decorative metal* Aluminium foil, a type of wrapping for food...
layers, separated by an insulation material and coiled on a core. One layer, which is placed between the voltage source
Voltage source
In electric circuit theory, an ideal voltage source is a circuit element where the voltage across it is independent of the current through it. A voltage source is the dual of a current source. In analysis, a voltage source supplies a constant DC or AC potential between its terminals for any current...
, such as inverter
Inverter (electrical)
An inverter is an electrical device that converts direct current to alternating current ; the converted AC can be at any required voltage and frequency with the use of appropriate transformers, switching, and control circuits....
, and a load, is called “the main foil”; this layer forms filter inductance
Inductance
In electromagnetism and electronics, inductance is the ability of an inductor to store energy in a magnetic field. Inductors generate an opposing voltage proportional to the rate of change in current in a circuit...
. Another foil, called “the auxiliary foil”, is connected to a neutral potential (e.g. earth), forming the useful capacitance
Capacitance
In electromagnetism and electronics, capacitance is the ability of a capacitor to store energy in an electric field. Capacitance is also a measure of the amount of electric potential energy stored for a given electric potential. A common form of energy storage device is a parallel-plate capacitor...
between foils. This way the self-capacitance of the main foil is crucially decreased. Filter is characterized by improved high-frequency performance (working frequency range is at least up to tens of MHz). The mutual inductance between foil layers is rather high, coupling factor is typically about 0.95-0.99. Higher the mutual inductance provided, better the damping properties of the hybrid LC filter.