Triac Motor Speed Control Arduino

Simple ac motor speed control circuit using bt136 triac.

Triac motor speed control arduino.

Thus the applied voltage to induction motor stator terminals is controlled by triac and its gate pulses 2. The same motor i had in my workshop. So far we have shown how to control on off status of an ac powered appliance with ibm watson iot that guide is important to use http s post request instead of using mqtt. Next inside setup function declare the triac pin as output as pwm output will be generated through this pin.

There are times when devices running on ac current also needs to be controlled by the microcontroller for switching control the ac appliances are usually interfaced to. Pulses synchronized to the ac sinewave half cycle are output from arduino digital pin 5 to the led in the moc3011 which also serves to isolate the high voltage ac from the low voltage components. And the variable speed val is declared to store the value of speed step. Fig 3 shows the triac firing circuit.

The complete control circuitry depends on only one parameter i e voltage. As the width of ic555 output pulse is varied using potentiometer the firing angle of triac. Diac triac phase angle control circuit it applies chopped ac waveform to motor and varies speed of ac motor. Over 3 years ago i published a simpel triac ac dimmer for the arduino.

A lot of arduino projects involve controlling devices running on dc voltage. To control the motor peed we could use a scr voltage regulator but at low rpm the motor will be weak with no torque. In which single phase induction motor speed control by using triac and 555 timer. We know that torque developed is proportional to square of the voltage.

Only one thing left the motor speed controller. This ac motor speed controller circuit is working based on the triac and diac. Int triac 6. The devices running on dc voltage are usually controlled by changing logic at gpio pins for switching control or by pwm for operational control.

Here the bt136 triac is connected to pin 6 of arduino. Yet in spite of the simplicity of the circuit the software needed was a bit complicated as it needed to keep track of the zero crossing of the ac signal then keep track of the time and then finally open the triac. The moc3011 opto coupler uses a photo triac as opposed to a transistor. You can use household equipment like a drilling machine to control the rotating speed of it.

Http post and mqtt has difference of use case in this present article we only restrict ourselves to discussions around esp32 arduino ac motor speed control module and circuit. So the circuit varies speed of ac motor by changing firing angle of triac by applying pwm generated using ic555 connected in monostable mode.