DIY Turbopump Controller

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ArkadiuszGibes
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Re: DIY Turbopump Controller

Post by ArkadiuszGibes » Fri Feb 05, 2021 3:31 pm

Hi

Here is a repository with kicad files: https://gitlab.com/arkadiusz.g/turbotronik1.0hw/
However, that was the first version of this driver, so it has some issues. One of them is LDO regulator, there is to much current that goes trough it and it is getting hot quite fast. I replaced it with Chinese dc/dc reg and it's fine - this is not updated in those pcb files.
This is a dc/dc converter that i used - https://allegro.pl/oferta/modul-przetwo ... 7563986495,
Also, as i built in on top of someones else code, it is using lcd that is driven by i2c -> parallel IC. From what iv'e seen, sometimes it was crashing so I had to repleace it with other type of lcd in my case.

Would be nice to update those files with DC/DC instead of LDO, and rebuild it with standard parallel interface for LCD so it could be used with cheap 2x16 displays. I can do this in free time, but feel free to do any modification you like.

Nikodem, I see that you are from Poland, if we would fix those "bugs" somehow then we could send it to production to china, and share some costs for pcbs.

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Nikodem Czechowski
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Re: DIY Turbopump Controller

Post by Nikodem Czechowski » Sun Feb 07, 2021 10:26 pm

I will download the files tommorow and try to do the updates you have mentioned.

What pump you would want to drive it?

We can share the costs, I would ever need 10 pcbs for that - PM me and we can discuss the details.

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Re: DIY Turbopump Controller

Post by ArkadiuszGibes » Mon Feb 08, 2021 8:47 am

Right now im playing with turbovac 50 pump, but it's damaged and i ordered turbovac360V. I will need to do some changes because TMP 360V works on lower voltage and frequency, but this is in most stuff that can be done by FW modifications. I will also repleace my 200V dc/dc converter to toroid transformer. Please shere the files when you update them.

Thanks

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Nicolas Krause
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Re: DIY Turbopump Controller

Post by Nicolas Krause » Mon Feb 08, 2021 10:29 pm

Hi Akradiusz, thanks for the links and files. If I could ask you to introduce yourself on the welcome forum it'd be a big help. The rules the old timers have setup here really help to preserve the quality of information on the forum!

ArkadiuszGibes
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Re: DIY Turbopump Controller

Post by ArkadiuszGibes » Tue Feb 09, 2021 8:19 am

I already did it.

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Nicolas Krause
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Re: DIY Turbopump Controller

Post by Nicolas Krause » Tue Feb 09, 2021 5:32 pm

Oh geez, I'm super sorry, missed that!

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Re: DIY Turbopump Controller

Post by John Futter » Tue Feb 09, 2021 6:39 pm

Nicolas
I have looked at your circuit
I did not use a micro directly to generate the drive frequency due to the danger of a reset or port hang from it.
There is a huge amount of stored energy in a turbo that is why in my diagram it was driven from the 4046 being used as a voltage controlled oscillator through a low pass filter that delayed abrupt voltage changes to the 4046. This filter should be changed to suit differing turbos ie longer time constant for 150 and 360 model pumps. Of coarse you change the buss rail voltage to suit these bigger pumps ie 14 / 28 volts for the tmp 360 and higher current mosfets and dont forget to lower the zener voltage in the buss protector
Fusor use includes high voltage power supplies and there will be the odd high voltage flashover that may reset your micro.
I certainly would not direct drive from a micro a larger turbo than the tmp50 due to the stored energy being released.
Even our turbo controllers have had the PSOC reset and the pump scream to a stop ( that what the big mosfet is for across the DC buss so that the electronics is saved from overvoltage from the motor back emf

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Nicolas Krause
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Re: DIY Turbopump Controller

Post by Nicolas Krause » Tue Feb 09, 2021 6:56 pm

Thanks for the clarification John, I think I've misunderstood something fundamental about the operation of the circuit. I'm going to have to digest your post and look over things.

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Re: DIY Turbopump Controller

Post by John Futter » Wed Feb 10, 2021 4:07 am

You are doing alright I'm just giving a bit of sage advice learnt from doing wrong it in the first place

ask away and i'll answer

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Nicolas Krause
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Re: DIY Turbopump Controller

Post by Nicolas Krause » Fri Feb 12, 2021 5:43 pm

Hi John

I have a TMP 50 so I'm dealing with one of the smaller pumps. But my general understanding of the circuit is that you use some discrete logic to generate the signals which drive the half bridge connected to the 3-phase motor of the pump. I had assumed that hooking up the microcontroller to the logic chips you'd used would have provided enough of an innate buffer to prevent damage to the microcontroller. Looking at my circuit again and your comments I assume the problem is with the current measurement portion of the circuit correct? I expose the microcontroller to large changes in voltage/current at that point. If I included some sort of opto-isolation on that connection would I avoid the problem? I've never used opto-isolation in a current sensing application before.

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