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Your Position: Home - Electrical Equipment & Supplies - Pro and Con and Info of Low vs High Frequency Transformer

Pro and Con and Info of Low vs High Frequency Transformer

Pro and Con and Info of Low vs High Frequency Transformer

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Mechatrommer

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Pro and Con and Info of Low vs High Frequency Transformer
« on: January 22, , 03:34:15 pm » currently me considering which transformer to be used in PSU design. either the normal 50/60Hz iron cored or high frequency (100KHz-500KHz) ferrite cored transformer. i only know one advantage of hi-freq transformer is its small size and lighter. what about efficiency and other aspects? the PSU planned to be in range somewhere 0-12V, 1-10A, the normal iron cored is heavy at this range, so using hi-freq is tempting. but i'm afraid i will be tricked by another aspect, any thought?

ps: while at it, i will also appreciate any links to high frequency transformer about info, spec, supply, type, pwm control circuit etc, thanks.
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock

IanB

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #1 on: January 22, , 06:35:36 pm » The 50/60 Hz transformers are powered from the mains and are used in linear supplies. The high frequency transformers are used in switch mode designs. Totally different circuit topology and not comparable at all.

Mechatrommer

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #2 on: January 22, , 07:00:54 pm » i dont mean the difference in topology/circuit. but say, power efficiency between two similar rated transformer.
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock

alm

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #3 on: January 22, , 07:05:14 pm » How can you compare the transformers without considering topology? A high frequency transformer will saturate at 50/60 Hz, a 50/60 Hz transformer will be very inefficient at 100 kHz.

Mechatrommer

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #4 on: January 22, , 07:19:20 pm » i mean like this. let say i have 2 transformer, A and B.

A is designed for 50/60Hz operation, iron cored and output 40Vpp 50/60Hz AC. further regulation output 12Vdc driving a load at 10A.
B is designed for 100KHz operation, ferrite cored and output 40Vpp 100KHz AC. further regulation output 12Vdc driving a load at 10A.

which one will give me lesser electricity usage if both is operated at same time duration in a month, A or B? well, rule of thumb answer pls.
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock

IanB

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #5 on: January 22, , 07:25:09 pm » The question is irrelevant as the two transformers are not comparable and can't be substituted.

The only way to answer your question is to look at a complete power supply design from front to back with specific parts identified and then measure the overall power supply performance.

As a rule of thumb, switching supplies will have a higher operating efficiency when higher output currents are needed at regulated voltages (10 A counts as high in this context). The greater efficiency comes at the cost of greater design complexity and possibly more noise on the output.

Neilm

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #6 on: January 22, , 07:26:10 pm » A mains transformer running at 50/60Hz will have very little loss, only in the windings and a small amount of core loss. They are also easy (relevantly) to make / design, and very reliable.

A switch mode supply working in kHz will have not only the losses in the core to consider, but also losses in the switching device and those inherent in the topology it is working in. If there are two FETs switching, then there will be two sets of switching losses. A SPMS will also be most efficient at a specific loading usually about 85% of full (although there are ways of improving things at low loads). A well designed and well laid out supply could be over 90% efficient. The same circuit poorly laid out with only slightly less good components could be only 75% and be prone to going bang.

Yours

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Mechatrommer

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #7 on: January 22, , 07:32:02 pm » ok now i got something. that smps is less efficient as low current load, right? but last time i heard smps can be 90% efficient as neil comfirmed it, but for normal 50/60Hz transformer, its only 50% efficient i heard/read. so is this a myth?
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock

IanB

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #8 on: January 22, , 07:38:59 pm » Everything is a myth.

You are quoting all sorts of random numbers without a clear specification or definition of what you are trying to measure or even that you have a working design.

It's like asking which goes faster, a car or a train?

Neilm

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #9 on: January 22, , 07:41:00 pm » There are many sorts of SMPS chip available. Some of these include techniques for improving the efficiency of the supply. I recently used a dedicated chip to charge a Li-Ion battery. It gets 24V in and charges the battery to 12.6V. When I measured the efficiency, it was over 90% from full load (3A) to when it finished (0.3A). The only problems I had were the FETs that I was originally told to use (we already used it on other products) didn't work at the frequency and got very hot (lowering the efficiency but I never bothered to measure it).

As  I tend to work on hand held / portable stuff, having large heavy mains transformers tends not to be feasable, so I don't really have any experience with 50/60Hz transformers.

Neil Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe. - Albert Einstein
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IanB

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #10 on: January 22, , 07:55:39 pm »
but for normal 50/60Hz transformer, its only 50% efficient i heard/read

What does this even mean? Stop throwing around random factoids and mis-remembered details and start doing science. Produce a specification, consider designs that can meet that specification, and then do a comparative evaluation of them to see which one is most efficient, or cost effective, or other criteria you have to judge them against.

For instance if you take a mains transformer rated at 12 V 10 A RMS on the secondary, you feed that through a bridge rectifier, and use it to drive a resistive load like a lamp or a heater, then the transformer will be very efficient.

If you start saying you want the DC output to be filtered and regulated with a low ripple, then the efficiency of those other parts will start to matter. The transformer itself will also become less efficient because it will now have a more difficult load to drive.

So it all depends. Random factoids won't cut it.

jahonen

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #11 on: January 22, , 08:02:09 pm »
ok now i got something. that smps is less efficient as low current load, right? but last time i heard smps can be 90% efficient as neil comfirmed it, but for normal 50/60Hz transformer, its only 50% efficient i heard/read. so is this a myth?

Maybe true for small transformers, but bigger ones are over 90%. That of course applies to AC/AC conversion efficiency only (just the transformer efficiency) with linear load.

Regards,
Janne

Mechatrommer

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #12 on: January 22, , 08:12:58 pm »
Stop throwing around random factoids and mis-remembered details and start doing science.
science needs money. if i have money, i wont ask
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock

Zero999

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #13 on: January 22, , 09:46:32 pm » I'd say a high frequency transformer has fewer losses.

All right you can't compare them side by side exactly but just look at how efficient an electronic halogen transformer is compared to a traditional mains frequency transformer, the former is 95% efficient, the latter is typically 85%. Given that most of the losses in the electronic transformer will be in the switching transistors, the actual transformer on its own will be much more efficient, although that's purely theoretical.

Mechatrommer

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #14 on: January 22, , 10:12:25 pm »
Given that most of the losses in the electronic transformer will be in the switching transistors, the actual transformer on its own will be much more efficient, although that's purely theoretical.
i believe the bolded quotation is my original question. if we take the topology into account, a linear voltage regulator will have an efficiency of Vout/Vin (Vin is unregulated voltage output on transformer secondary, Vout is PSU regulated output), so say we are regulating 1V from 20V, the efficiency is only 5%!
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock

ejeffrey

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #15 on: January 22, , 10:46:29 pm » Yeah, it is just too complicated to say.  It only makes sense to compare two specific devices under specific operating conditions, or to compare two approaches under a common optimization metric including cost, efficiency, and so forth.  A 50/60 Hz transformer followed by a linear regulator will essentially always be less efficient than a SMPS, but that is due to many factors, not only the transformer itself, and is as much guided by cost effectiveness than anything else.

The advantages for low frequency transformers are: lower eddy current losses, stray capacitances, and antenna losses.  The advantages for high frequency devices is that magnetizing current is much less.  This means you need less inductance so you can use fewer turns of larger gauge copper, reducing copper losses, and cores of lower susceptibility, which allows lower hysteresis losses and higher resistivity for less eddy current losses even at high frequency.

However, this is dwarfed by the main differences between a linear and switch-mode supply.  A SMPS transfers less energy per cycle due to the higher operating frequency, and therefore can store that energy in an inductor or gapped transformer.  This allows efficient regulation through duty cycle control.  A linear supply instead stores the energy in a capacitor and uses a variable resistor to regulate the voltage, dissipating a lot of power in the process.  This makes SMPSs much more efficient than linear power supplies with line frequency transformers, but isn't really related to the losses in the transformer at all.

Finally, an SMPS must consider switching losses in the MOSFETs and diodes.  A line transformer supply simply doesn't have these losses because the AC waveform comes to you from the power company.  These losses get worse with frequency, so generally high frequency SMPSs have more loss than lower frequency SMPS.  It isn't really cut and dry though, because the higher frequency you go, the smaller and cheaper the transformers, inductors, and capacitors can be, allowing for cheaper 'oversizing' for improved efficiency.  A properly cost-optimized design will have to trade off the cost of the silicon vs. the cost of the passive devices vs. the desired efficiency, plus performance requirements like ripple, noise,  regulation, and emissions to find an optimal design.

If I had to give an answer to your relatively meaningless question, I would probably say that the physics favors  low frequency but economics favors high frequency.  If your really want to set a record for minimum transformer losses and aren't concerned with cost or output power, a low frequency transformer will probably win.  That lets you minimize antenna losses and eddy currents, which are a problem even at zero power.  Signal transformers can be really high efficiency at low audio frequency, but are expensive, bulky, and very low power.  If you have to make something cost effective, a high frequency transformer will win every time.

amspire

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #16 on: January 22, , 10:57:43 pm »
ok now i got something. that smps is less efficient as low current load, right? but last time i heard smps can be 90% efficient as neil comfirmed it, but for normal 50/60Hz transformer, its only 50% efficient i heard/read. so is this a myth?

You could probably make steel cored transformers with 98% efficiency  or better, but it is limited by economics. To reduce winding resistance, you need thicker wire, but then you need more bobbin space for the wire, so the whole transformer has to be bigger, which means each winding turn is now much longer so you need to make it even thicker ... You can end up turning a 1Kg transformer into a 20Kg transformer very easily. The ultimate quality steel core transformers end up being relegated to metrology measurement tasks like ultra-precision transformer bridges and dividers.

In practice, weight and economics means you usually design a transformer with as much losses as you can manage comfortably.

Switching power supplies can be over 95% efficiency, but again it comes down to economics. Going from 94% efficiency to 95% efficiency could double the price - who is going to pay for that? Most people are happy for anything over 80% efficiency.

Richard

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #17 on: January 22, , 11:06:31 pm »
currently me considering which transformer to be used in PSU design. either the normal 50/60Hz iron cored or high frequency (100KHz-500KHz) ferrite cored transformer.

Are you planing on using switchmode for either option? Greek letter 'Psi' (not Pounds per Square Inch)

IanB

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #18 on: January 22, , 11:32:50 pm »
You could probably make steel cored transformers with 98% efficiency  or better, but it is limited by economics.

I read that the DOE has mandated new efficiency standards since for power distribution transformers in the USA. New transformers are mandated to be up to 99.5% efficient and never less than 97% efficient depending on size and type. Evidently this increases size, weight and cost, but since it is a government regulation customers have to take the hit.

Zero999

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #19 on: January 22, , 11:40:56 pm »
Given that most of the losses in the electronic transformer will be in the switching transistors, the actual transformer on its own will be much more efficient, although that's purely theoretical.
i believe the bolded quotation is my original question. if we take the topology into account, a linear voltage regulator will have an efficiency of Vout/Vin (Vin is unregulated voltage output on transformer secondary, Vout is PSU regulated output), so say we are regulating 1V from 20V, the efficiency is only 5%!
What's that got to do with it?

It's perfectly possible to use an old fashioned iron transformer/rectifier with a switching regulator on the secondary to achieve a higher efficiency than a linear regulator.

Mechatrommer

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #20 on: January 22, , 11:48:17 pm »
Are you planing on using switchmode for either option?
cant decide yet as i have much unknown parameters right now. the latest idea is to use both linear+smps transformer/regulator (due to low voltage requirement pwm chip unable to cope with). maybe my original question (and my mind) is not very clear about this issue. but now i have to agree with ejeffrey's and amspire's reply, its not about transformer efficiency alone. in the end, the final product that matters. but i think ejeffrey has answered the original question spot onQuote
If your really want to set a record for minimum transformer losses and aren't concerned with cost or output power, a low frequency transformer will probably win
but it differ from Hero's answer about theoritical efficiency of smps transformer but well i guess it doesnt matter as everyone agreed, it doesnt matter. but then, the "weight" issue still a dilemma for me. sorry i didnt mention that portability of the psu is one of my main concern, beside the efficiency.
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock

saturation

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #21 on: January 24, , 01:07:57 pm » One thing that can save you money and time is simply tear down and examine any wall wart PSU made in the past 10 years; at worst its minimal parts and is easy to study.  At best, its well made and you'll see many features added versus the cheapo one.  These PSU are all over the place and are cheaper than buying parts.

https://www.eevblog.com/forum/index.php?topic=.0

There's a lot of SMPS design on the web.  Very recently on eevblog a book has come to light to rival Art of E.  Its huge, but has a lot of expert advice, its been out since , is very well written and its free!

http://www.thetan.plus.com/seekrets/index.html




Best Wishes,

 Saturation

Mechatrommer

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #22 on: January 24, , 01:27:40 pm » Quote
One thing that can save you money and time is simply tear down and examine any wall wart PSU
you got my senses remotely, i'm doing it right now, except not 10 years, most of my stocks are recent, including the cheapo's which i'm concentrating since they are simpler to dechipher. including the one similar to mikeelectricstuff's (link) which i already blown apart, sadly i havent been able to dechipher the blocking oscillator circuit. i will avoid complex design right now to avoid dizziness thanks for the book link.
Nature: Evolution and the Illusion of Randomness (Stephen L. Talbott): Its now indisputable that... organisms “expertise” contextualizes its genome, and its nonsense to say that these powers are under the control of the genome being contextualized - Barbara McClintock

saturation

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #23 on: January 24, , 03:11:33 pm » For safety, since these are mains powered devices its helps to use a variac and an isolation transformer.  They are easy to find internationally and you can see how the PSU responds to lower input voltage and isolate yourself from the mains.  I think them a must have for designing and troubleshooting mains powered PSU, linear or isolated. 

There are many copies of the Staco designed benchtop variac and you can plug this into any isolation transformer.

Chinese copy, about $50-70.  I have one of these, I tore it down the transformer is very well made, electrically functional but the finish is crude.  YMMV depending on what 'clone' you end up with.  If you operate it at 50% its capacity, it very likely safe to use.   Its about 4 x 5 inches in size.

 

Staco Original, about $300-500!




Quote
One thing that can save you money and time is simply tear down and examine any wall wart PSU
you got my senses remotely, i'm doing it right now, except not 10 years, most of my stocks are recent, including the cheapo's which i'm concentrating since they are simpler to dechipher. including the one similar to mikeelectricstuff's (link) which i already blown apart, sadly i havent been able to dechipher the blocking oscillator circuit. i will avoid complex design right now to avoid dizziness thanks for the book link.

Best Wishes,

 Saturation

Zero999

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Re: Pro and Con and Info of Low vs High Frequency Transformer
« Reply #24 on: January 27, , 06:42:37 pm »
The advantages for low frequency transformers are: lower eddy current losses, stray capacitances, and antenna losses.  The advantages for high frequency devices is that magnetizing current is much less.  This means you need less inductance so you can use fewer turns of larger gauge copper, reducing copper losses, and cores of lower susceptibility, which allows lower hysteresis losses and higher resistivity for less eddy current losses even at high frequency
The copper losses tend to dominate in a low frequency transformer so all things being equal, a higher frequency transformer will be more efficient and past a certain frequency an air core transformer becomes a more viable solution but then skin effect losses increase.


Quote
However, this is dwarfed by the main differences between a linear and switch-mode supply.  A SMPS transfers less energy per cycle due to the higher operating frequency, and therefore can store that energy in an inductor or gapped transformer.  This allows efficient regulation through duty cycle control.  A linear supply instead stores the energy in a capacitor and uses a variable resistor to regulate the voltage, dissipating a lot of power in the process.  This makes SMPSs much more efficient than linear power supplies with line frequency transformers, but isn't really related to the losses in the transformer at all.

Finally, an SMPS must consider switching losses in the MOSFETs and diodes.  A line transformer supply simply doesn't have these losses because the AC waveform comes to you from the power company.  These losses get worse with frequency, so generally high frequency SMPSs have more loss than lower frequency SMPS.  It isn't really cut and dry though, because the higher frequency you go, the smaller and cheaper the transformers, inductors, and capacitors can be, allowing for cheaper 'oversizing' for improved efficiency.  A properly cost-optimized design will have to trade off the cost of the silicon vs. the cost of the passive devices vs. the desired efficiency, plus performance requirements like ripple, noise,  regulation, and emissions to find an optimal design.
The comments regarding the linear regulator aren't relevant to the discussion.

Low frequency transformers are more frequently used without a linear regulator than with one and even high frequency transformers are often used outside of a switching regulator for powering halogen lamps. It's true you can't compare them side by side but most of what you've said applies to linear vs switching regulators than anything else.

What is high frequency transformer vs normal transformer?

Transformers are essential components in electrical and electronic systems, serving the fundamental purpose of transferring electrical energy between circuits through electromagnetic induction. While traditional transformers have been in use for over a century, high frequency transformers represent a more specialized development that has become increasingly important in modern power electronics. This article provides a detailed comparison between these two types of transformers, examining their design principles, operational characteristics, applications, advantages, and limitations.

Fundamental Operating Principles

Normal (Low Frequency) Transformers

Traditional transformers, often referred to as "normal" or "low frequency" transformers, typically operate at power frequencies of 50Hz or 60Hz. These transformers follow the basic transformer equation:

= 4.44 × f × N × B × A

Where:

V is the voltage

f is the frequency

N is the number of turns

B is the magnetic flux density

A is the cross-sectional area of the core

At these low frequencies, the transformer design emphasizes large magnetic cores (usually made of silicon steel laminations) to handle the substantial magnetic flux requirements while minimizing eddy current losses.

High Frequency Transformers

High frequency transformers operate at significantly higher frequencies, typically ranging from several kHz to several MHz. The same fundamental transformer equation applies, but the increased frequency allows for dramatic changes in design approach. Higher frequency operation enables:

Reduced size and weight due to smaller core requirements

Increased power density

Faster transient response

Different core material requirements (ferrites instead of silicon steel)

Design Differences

Core Materials

Normal Transformers:

Use laminated silicon steel (electrical steel) cores

Laminations are typically 0.3-0.5mm thick to reduce eddy currents

High saturation flux density (around 1.5-2 Tesla)

Relatively high core losses at high frequencies

High Frequency Transformers:

Employ ferrite materials (Mn-Zn or Ni-Zn) or powdered iron cores

No need for laminations as ferrites are naturally resistive

Lower saturation flux density (0.3-0.5 Tesla)

Excellent high frequency performance with minimal eddy current losses

Winding Techniques

Normal Transformers:

Use relatively thick copper conductors

Often employ layered or helical winding techniques

May use multiple parallel strands to reduce skin effect (though less critical at low frequencies)

Larger insulation requirements due to higher voltages

High Frequency Transformers:

Frequently use Litz wire (multiple individually insulated strands) to combat skin and proximity effects

Employ sectional or interleaved winding techniques to reduce leakage inductance and parasitic capacitance

Often have fewer turns due to the high frequency operation

May use planar winding techniques in PCB-based designs

Size and Weight Considerations

The most noticeable difference between the two transformer types is their physical size relative to their power handling capacity. High frequency transformers can be 5-10 times smaller than their low frequency counterparts for the same power rating. This size reduction comes from two factors:

The increased frequency allows for fewer turns to achieve the same voltage transformation

The reduced flux requirement permits smaller core cross-sections

Performance Characteristics

Efficiency Considerations

Normal Transformers:

Typically achieve 95-99% efficiency at rated load

Losses dominated by:

Copper losses (I²R losses in windings)

Core hysteresis losses

Eddy current losses in the core

Efficiency optimized for a narrow frequency range (50/60Hz)

High Frequency Transformers:

Efficiency generally lower, typically 85-95%

Loss mechanisms include:

Skin and proximity effects in windings

Core losses that increase with frequency

Dielectric losses in insulation

Efficiency varies significantly with frequency and requires careful design optimization

Thermal Management

Normal Transformers:

Larger surface area facilitates natural cooling

Often use mineral oil or other coolants in power applications

Thermal time constants are relatively long

Recommended article:
How Does Explosion Proof Strobe Light Work?

Link to YuYang Magnetic

High Frequency Transformers:

Higher power density creates challenging thermal management requirements

Often require forced air cooling or heat sinks

May use thermal vias or other techniques in planar designs

Thermal time constants are shorter due to smaller mass

Parasitic Elements

Normal Transformers:

Leakage inductance is relatively high but less critical at low frequencies

Winding capacitance is generally not a significant concern

Parasitic effects often modeled as lumped elements

High Frequency Transformers:

Leakage inductance and winding capacitance become critical design parameters

Parasitic elements can significantly affect performance and mu

st be minimized

Often require complex distributed parameter models

May need resonant techniques or snubber circuits to manage parasitics

Applications

Normal Transformer Applications

Power distribution networks (step-up and step-down transformers)

Utility power supplies for industrial and residential use

Audio frequency applications

Line frequency power supplies for traditional electronics

Isolation transformers for safety

High Frequency Transformer Applications

Switch-mode power supplies (AC-DC and DC-DC converters)

RF circuits and communication systems

Induction heating systems

High frequency inverters (for renewable energy systems)

Aerospace and military power systems where size/weight are critical

Electronic ballasts for lighting

Wireless power transfer systems

Advantages and Disadvantages

Normal Transformers

Advantages:

Proven, reliable technology with well-understood characteristics

High efficiency at design frequency

Can handle very high power levels (up to hundreds of MVA)

Simple construction with readily available materials

Long operational life with minimal maintenance

Disadvantages:

Large and heavy for their power rating

Limited to narrow frequency range

Poor performance at frequencies other than design frequency

Difficult to adapt to modern power electronics applications

High Frequency Transformers

Advantages:

Compact size and light weight

Can be integrated into PCB designs (planar transformers)

Enables high power density systems

Faster transient response

More suitable for modern power conversion topologies

Disadvantages:

More complex design process

Higher losses per unit power

Core materials more sensitive to temperature variations

More susceptible to parasitic effects

Limited maximum power handling compared to large power transformers

Future Trends

The evolution of transformer technology continues to push toward higher frequencies and greater power densities. Emerging developments include:

Advanced Core Materials: New nanocrystalline and amorphous materials offering better high frequency performance with lower losses.

3D Printing: Additive manufacturing techniques enabling complex transformer geometries that were previously impossible to fabricate.

Wide Bandgap Semiconductors: Devices using SiC and GaN technologies enabling even higher frequency operation of power converters, driving transformer designs to higher frequencies.

Integrated Magnetics: Combining multiple magnetic functions (transformers, inductors) into single components to reduce size and improve performance.

Smart Transformers: Incorporating monitoring and control electronics directly into transformer designs for improved reliability and performance.

The choice between high frequency and normal transformers depends fundamentally on the application requirements. Normal transformers remain the undisputed solution for utility-scale power distribution and low frequency applications where size and weight are secondary concerns. High frequency transformers, by contrast, enable the compact, efficient power conversion needed in modern electronics, renewable energy systems, and specialized applications where space and weight are at a premium.

As power electronics continue to evolve toward higher frequencies and greater efficiencies, the importance of high frequency transformer technology will only grow. However, both transformer types will continue to coexist, each serving distinct but vital roles in our electrified world. The ongoing development of new materials and manufacturing techniques promises to further enhance the capabilities of both transformer types, ensuring their relevance in future power systems.

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