Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Is flux-leakage or leakage-inductance useful?

Status
Not open for further replies.
picotube

picotube

Member level 5
Joined
Sep 24, 2004
Messages
84
Helped
6
Reputation
12
Reaction score
0
Trophy points
1,286
Activity points
781
leakage inductance

Is flux-leakage or leakage-inductance useful in electronic circuit/device design? For example, in which situation that a designer purposely increases the flux-leakage so that his design works better?
 

ac power control using leakage inductance

No. Work at high frequencies can become unstable with great leakage inductances.
These terms you mentinoed are usually used with electrical machines and with electronics one use term parasitic inductance. Of course, there exists some adjustment of this parasitic parameters to make circuit work well.
 

improve leakage inductance

Leakage inductance is due to magnetic flux lines that do not reach from primary to secondary. Low leakage inductance is always desireable because it indicates proper coupling. It is measured in transformers on a winding with the other windings shorted.

Parasitic inductance is the result of magnetic coupling where it is not desired - such as the leads of a resistor, capacitor, IC, etc. In the real world it cannot be avoided, but it is undesirable because it complicates the design of high frequency equipment.
 

transformer dc-dc converter leakage inductor

There are cases where the leakage inductance is intentionally used for specific purposes. In the old days of inductively coupled tuned circuits used as band pass filters in IF amplifier chains, the coupling coefficient was intentionally made less than 1.0 to produce the desired frequency response.

I have seen broad band transformers with shunt capacitors across primary and secondary. This is called "building out" the transformer. These in conjunction with the intentionally set leakage inductance form a low pass filter which extends the transformer bandwidth. It trades a wider flat response region for a faster falloff out of band.
 

leakage flux

it is mostly bad....in switching circuits it causes spikes over the switching element(mosfet, igbt etc..)..
leakage-inductance some times used in switch mode power supplies achieve zero voltage or zero current switching...
phase shifted dc dc converter one of them(i don't know the others:))but probably there are some topologies using leakage inductance for this purpose)...
in phase shifted dc dc converter ZVS is achieved via resonance beetven mosfet output capaticance and leakege inductance...
 

as a second answer leakage was using in old welding machinaries(today also in production in low quantities) to control welding current.............(a big machine whic has a rotating bar..with this bar you are moving the centre of the transformer...so you are changing leakage...very inefficent way but it has worked very well for years...)
 

The concept of leakage inductance is used to model the flux coupled with wone of the winding but not with the other. So the energy stored into the leakage inductance is not delivered across the transformer.

Usually Leakage inductance is bad but it can somehow useful in multiple output Switching power supply to improve cross regulation.

National and TI have several papers on this topic
 

The leakage inductance can be useful in DC/AC converters to creation of sine wave output voltage. In this case leakage inductance of a secondary winding of the transformer is an element of the low-pass filter.
For example, it is used in DC/AC converters for cold cathode fluorescent lamps.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top