need help on controlling ac motors with microcontroller

controlling a 230v ac with a microcontroller

pls, i need help on controlling AC motors using microcontroller with pulsewidth modulation. please any idea, circuit diagram, source code will be appreciated. thanks in anticipation.

ac motor microcontroller

3 phase or single phase motor ??
there are even lot more specs you need to say like power rating,frequency,type of control(speed or direction) etc...
pls be specific with your questions.

how to build a variation of speed triphasic motor

cameo_2007 said:

3 phase or single phase motor ??
there are even lot more specs you need to say like power rating,frequency,type of control(speed or direction) etc...
pls be specific with your questions.

Click to expand...

thanks for your response.

this are my specs

1. 50hz
2. speed
3. direction
4. single phase
5. from 1kw upward
6. nominal voltage of 230 volts.

thanks for your help.

ac motor with microcontroller

can just mention what is your application??
because there are different kind of controls suiting the applications.
As if you want some basic control,you can go with a simple triacs etc or if you need a proffessional sophisticated control,then you need to go with microcontroller based/pwm based/H-bridge topologies.
pls mention your application and what is that you are looking for in terms of budget and your resources including your knowledge in electronics.

controls of ac motors using microcontrollers

I have a small home device which i used to wind and unwind coils for transormer etc. its a motorised coil winder. which have been using a DC motor before. but now i wish to change the design and incoporate a single phase induction motor for more efficiency.

iwould prefer to use microcontroller based PWM and H-Bridge topology as the whole circuit will be controlled by PIC16f877A.

it is going to have a keypad for for inputing and control of the speed and direction, lcd and seven segment display

i hope you can get the overview of what i have. the first constrution is controlled via a parrallel porrt on my computer but now i want to use a microcntroller so that i can make it mobile and more versatile

single phase ac drive using microcontroller

babatundeawe, regarding AC induction motor there are a lot of staff on freescale TI and similar manufacturers sites. You can get source code schematics to start your project.

BTW, why are you shifting from dc motor to ac ?

If you are new to this field i would recommend to buy VFD driver which costs 100-200 usd. Otherwise be prepared to sacrifice some amount of money on burnt mosfet and/or igbt transistors.

microcontroller based ac motor drives

artem said:

babatundeawe, regarding AC induction motor there are a lot of staff on freescale TI and similar manufacturers sites. You can get source code schematics to start your project.

BTW, why are you shifting from dc motor to ac ?

If you are new to this field i would recommend to buy VFD driver which costs 100-200 usd. Otherwise be prepared to sacrifice some amount of money on burnt mosfet and/or igbt transistors.

Click to expand...

yeah thanks.
but can you kindly give me the link to the site i am not in the US so i have to make do with the available components here.

single phase ac winder drive

babatundeawe said:

cameo_2007 said:

3 phase or single phase motor ??
there are even lot more specs you need to say like power rating,frequency,type of control(speed or direction) etc...
pls be specific with your questions.

Click to expand...

thanks for your response.

this are my specs

1. 50hz
2. speed
3. direction
4. single phase
5. from 1kw upward
6. nominal voltage of 230 volts.

thanks for your help.

Click to expand...

I've seen such design (PWM based) on a washing machine.
Usually you will need an 230V inverter (it generate sinusoidal output voltage with variable frequency between 10Hz and 150Hz) which is difficult for manufacturing (but not impossible even in Nigeria)

No I'm not nigerian but when I'm working for some rich people I have the feeling I am (even I'm white)... so I understand your life quite well.

For the PWM AC variation, you need a motor with two coils (one for capacitor called in folcklore as "fake phase" and another one for the 230V supply).
Changing the capacitor position will change the motor direction (ie clockwise if the capacitor is in series with coil 1, the coil1 + capacitor and coil2 is connected directly to de 230V, anticlockwise if the capacitor is connected in series with coil2 while coil1 and coil2 assembly is connected directly to 230V)

The speed can be modified if the coil connected to 230V gets a PWM instead of a permanent AC voltage. However the mechanical couple is poor and the PWM must have a small frequency (around a few Hz, less than 50Hz anyway).

I found an application note describing in figures what I said in words:
https://ww1.microchip.com/downloads/en/AppNotes/00887a.pdf
The schematic about is figure6 page4. If you change the capacitor position from starting winding to main winding you've got reversal direction. On 1KW motors, there is a small diameter wire difference between start winding and main winding. You mai use even a triphasic motor and use only two phases, but then the starting scheme is the one from figure7.

Controlling the main winding in PWM is a challenge. Solutions could be Gate Turn Off (hard to find I've guess)
https://en.wikipedia.org/wiki/Gate_turn-off_thyristor
a simple thyristor with turn off at zero load (difficult because the motor is an inductive load and you need to sense the current) or even a relay with a PWM with max frequency of 1Hz. In this last way you need a gear coupled at the motor shaft and a mechanical load at the end of the gear (looking like the rotor of a gyroscope: https://en.wikipedia.org/wiki/Gyroscope), to keep constant the motor speed.

Success,

how to give plus on triac gate by microcontroller

babatundeawe said:

artem said:

babatundeawe, regarding AC induction motor there are a lot of staff on freescale TI and similar manufacturers sites. You can get source code schematics to start your project.

BTW, why are you shifting from dc motor to ac ?

If you are new to this field i would recommend to buy VFD driver which costs 100-200 usd. Otherwise be prepared to sacrifice some amount of money on burnt mosfet and/or igbt transistors.

Click to expand...

yeah thanks.
but can you kindly give me the link to the site i am not in the US so i have to make do with the available components here.

Click to expand...

Look to bottom of this link for manufacturer list:
https://en.wikipedia.org/wiki/Variable-frequency_drive

imho you will need 3 phase ac induction motor as changing speed in wide range can not be properly done for single phase ac motors (phase shifting capacitor value must be changed ).

triphasic ac motors

You can use Triac drive that is a simple control for AC single phase induction motor, by using phase control method plus the PID controller. You must using the external interrupt for dtect the zero crossing of AC, then using the timer to make the signal for control phase, the PID will help you to adjust the timing of phase control.

controlling ac

Sir I Want help for key points for single phase induction motor drive design in microcontroller