Inductor as a current source

[zesla]

Hi,

Is an inductor a current source? If so what it does mean and what are the usages?

Thanks a bunch.

 

[Ian Rogers]

An inductor is an energy storage device.. when an AC current is passed through an inductor a magnetic field is produced that can change the condition of the AC current being passed through it...They are used as 'Chokes' in power supplies to filter noise, or switched mode power supplies they are used to build up a magnetic field and then dump the energy into a capacitor by the use of a power transistor switching at high speed (similar to the coil (inductor) in car ignition systems).

Obviously the largest usage is in transformers where the coil energy is transferred into a parallel inductor of a different size (power conversion).

Lastly they are used in passive filters (same as the choke really) to filter out higher / lower frequencies..


I never seen the used in a current source.

But!!!!! I've been wrong before...... I sure someone will tell me if I am..

Ian

 

[colin55]

An inductor is an energy storage device. We normally use an inductor for its capability to provide an increased output voltage (when the magnetic field collapses) and we say it provides a voltage source (an increased voltage source). At the same time it is providing a current source, but this current source is less than the input current to the circuit, so we normally neglect this feature as it is not an "improvement." However any output from an inductor includes a certain amount of current and this may be what is being referred to.
When an inductor is used as a filter to reduce spikes, the output consists of a voltage and a current. The inductor is only modifying the voltage by reducing the ripple (spikes). It does not change the value of current.

 

[dpj]

If you are expecting it to work like one then its coil..
It can generate a small voltage and current when placed in varying magnetic field..

 

[crutschow]

A current flowing through an inductor will tend to persist due to the inductance and the inductor will generate whatever voltage is required for that current as determined by the load, so it initially acts like a constant-current source. But the current will exponentially decrease at a rate determined by the inductance and the load values, as the inductive energy is dissipated in the load. So you could say it can momentarily provide a constant current but that current immediately starts to decrease.