40# 🚀 How good are Würth Inductors?
SuperPowers for Electrical Engineers 🦸🏻♂️
👋 Hello Supergineers! Dr. Molina here! 👨🔧
Welcome to Dr.Molina Newsletter, where I break down Magnetic designs for you every week, in 4 minutes.
In the old times, most engineers need to wind every inductor. However, today, there are some manufacturers producing very interesting stuff. Especially power inductors.
There are engineers who criticize manufacturers. Most cases are due to low informative datasheets.
Since Würth doesn´t pay me or Frenetic, I can speak freely.
Today, I will analyze a specific power inductor of Wurth Electronik which is in our Library.
RedExpert Simulation
The component under test will be the WE-HCF 7443640680.
This is a typical power inductor of 6,8 uH rated current of 30 A (55A saturation).
The test consists of applying 25A of DC current.
According to with RedExpert, the resultant losses are 1,5W and 30,9ºC of increment of temperature. If we consider Tamb= 30ºC, the max. the temperature will be Tmax=60,9ºC.
Frenetic Simulation
I have simulated the inductor at Frenetic, you can simulate it by visiting Frenetic’s library.
The simulated temperature is 43ºC and 1,68W of losses. This simulation considers an Rdc=2,67 mOhm. Since there is no AC current, core losses are zero.
Lab Test
We have run an experiment in the Lab with the following results.
Temperature = 52 ºC
Plosses= 1,58W (basically, the energy provided by the power supply)
Summary
As you can see in the table, all the simulations are very close to the lab experiments. The difference is in the heat dissipation models. Redexpert is more conservative with heat dissipation. To be honest, I’m not an expert in temperature models. At Frenetic, there is a specific group of engineers investigating this topic in detail.
However, I want to highlight the good prediction of Redexpert. I’m not a fan of Redexpert, especially because is very limited and the interface is very old style, but the data of this inductor is fulfilling my expectations as an engineer.
Well done Würth!! 👏
This inductor provides a reasonable power density and its dissipation area is considerable.
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Nice comparison article! In my personal judgement, if I would have daily work as HW engineer, to prevent quality issues, I would prefer simulation tool that is providing losses or self heating temperature predictions higher than actual measurements instead of lower ( provided that difference is similar ) to avoid under engineered selection of components that can lead later on in component failure when working close to it’s rated functional specs.