Anyone tried making a VFD with a prop ??
Igor_Rast
Posts: 357
Hello Fellow Forum Members
I am currently busy with a project that I started about 2 years ago , Building a climate controller to control the environment fully automated.
In my quest to find a microcontroller to do it all for me I remembered that I followed a class long ago about microcontrollers , and we used the basic stamp to get to understand how they work, doing the famous blinking led etc.
Googling around, and remembering the simplicity of programing with the basic stamp, Parallax was the first search. After finding out that the Propeller chip is the next big thing having 8 cores, (8 * basic stamp in on chip , that was my thinking at the time ). I quickly ordered a demo board. The guys at gadgetgangsters had a nice one, the propeller platform usb . Already assembled, Ready to Go ( its now replaced by the propeller quickstart). Nuff said
Time went by, tried different things with it, a lot of Forum reading and a project thats the fruits of all this
Currently I am using this setup .
*Parallax Propeller
*Wizio820 Module ( Wiznet W5200)
*4 digit reflective LCD controlled by 4 HC595 Shift registers
*4 x simple tactile pushbuttons
1 x SHT-11 Sensiron temp&humidity sensor
2 x SSR 8amp230vac.(Zero cross)
NO SD card
I have a Controller built thats gonna keep track of the temp and humidity, and fire up one or 2 relays to keep it under control , turning on eg a fan. or humidifier
With the Wiznet I now have a webpage running (WORK IN PROGRESS , With good Help from Mike G making it more usefull ) Where the same temp and humidity is getting displayed in a HTML5 graph , your able to change some settings, and see whats going on . as mentioned its a work in progress. So its not fully ready . catch a glimpse on the form. Help is much appreciated.
Anyway Its almost coming to a nice ending with a complete plug&play system powered by the propeller.
Having that working you can Imagine that its not the end of it .
Currently the propeller can interfere with the outside word taking action let say , by putting power to the SSR so we can turn stuff on or off ( a nice 230VAC socket)
For most things this is enough, However if we want to controll the speed of a fan , in place of just putting it on or off so we can save some energy.
We will have to use a VFD drive , to let the frequency and amplitude of the power source fluctuate like we want to get the fan running at diferent speeds .
with fan I mean the more commonly stumbled upon 230VAC- 1 phase fan .
Adding this to the current going project will be a nice add on , Any advice or work done on a VFD would be nice
(schematics , The magical formula that calculates everything explanation, work already done, just a link)
Igor
I am currently busy with a project that I started about 2 years ago , Building a climate controller to control the environment fully automated.
In my quest to find a microcontroller to do it all for me I remembered that I followed a class long ago about microcontrollers , and we used the basic stamp to get to understand how they work, doing the famous blinking led etc.
Googling around, and remembering the simplicity of programing with the basic stamp, Parallax was the first search. After finding out that the Propeller chip is the next big thing having 8 cores, (8 * basic stamp in on chip , that was my thinking at the time ). I quickly ordered a demo board. The guys at gadgetgangsters had a nice one, the propeller platform usb . Already assembled, Ready to Go ( its now replaced by the propeller quickstart). Nuff said
Time went by, tried different things with it, a lot of Forum reading and a project thats the fruits of all this
Currently I am using this setup .
*Parallax Propeller
*Wizio820 Module ( Wiznet W5200)
*4 digit reflective LCD controlled by 4 HC595 Shift registers
*4 x simple tactile pushbuttons
1 x SHT-11 Sensiron temp&humidity sensor
2 x SSR 8amp230vac.(Zero cross)
NO SD card
I have a Controller built thats gonna keep track of the temp and humidity, and fire up one or 2 relays to keep it under control , turning on eg a fan. or humidifier
With the Wiznet I now have a webpage running (WORK IN PROGRESS , With good Help from Mike G making it more usefull ) Where the same temp and humidity is getting displayed in a HTML5 graph , your able to change some settings, and see whats going on . as mentioned its a work in progress. So its not fully ready . catch a glimpse on the form. Help is much appreciated.
Anyway Its almost coming to a nice ending with a complete plug&play system powered by the propeller.
Having that working you can Imagine that its not the end of it .
Currently the propeller can interfere with the outside word taking action let say , by putting power to the SSR so we can turn stuff on or off ( a nice 230VAC socket)
For most things this is enough, However if we want to controll the speed of a fan , in place of just putting it on or off so we can save some energy.
We will have to use a VFD drive , to let the frequency and amplitude of the power source fluctuate like we want to get the fan running at diferent speeds .
with fan I mean the more commonly stumbled upon 230VAC- 1 phase fan .
Adding this to the current going project will be a nice add on , Any advice or work done on a VFD would be nice
(schematics , The magical formula that calculates everything explanation, work already done, just a link)
Igor
Comments
Short answer: Yes!
Any info abou schematics builup orso , how and why
Looks like a badd *** vfd , hope you can share some info about it
is this one your work ??
I was kidding. What you see in the picture really looks like a VFD but it's actually a servo drive. The main board with the big electrolytic caps is a rectifier + 3 phase power stage as in a VFD. But the daughter board with the propeller is much more sophisticated. It features a high speed incremental encoder interface, a sin/cos glas scale input, a resolver interface and current vector control. So it would be overdosed and much too complicated for your application.
For controlling the speed of a single phase fan motor I'd suggest using an SCR speed controller. I think there are some "proportional SSRs" available that can be controlled with a PWM signal. Or you could build your own by controlling the gate of a triac with the propeller. It would only require two propeller pins an optocouplers. One for phase detection of the power line and one for output to the triac gate.
the calculations that take place , to get the right amplitude and frequency is where I cant find any good simple explanation that i can understand .
so that frequency plus amplitude of the signal get conditioned right according to the setted speed (1-100%)
any simple explanations you know off on the web somewhere ?
look at this: http://en.wikipedia.org/wiki/Phase_fired_controllers. If your circuit already includes a transformer you could use the AC voltage and a comparator to tell the propeller when the AC line in changing polarity. You then wait for a variable delay (0..10ms for 50Hz or 0.833ms for 60Hz) until you fire the thyristor or triac.
1..100% speed would be hard to do without a closed loop speed control. But I think 1..100% of power should be possible. Power of a fan (airflow times pressure) rises with the square of speed so it would be sufficient to control the speed from 10 to 100%.
There was a spammer here earlier, to which @localroger replied. That's what really re-awoke the thread.
On the upside... Turned out to be a nice reminder of a neat Propeller project from ManatWork !