does somone hve n idea of how to do a control of n induction single phase motor?

[shailesh5]

does somone have an idea of how to do a control of an induction single phase motor , i ve done one project in my course , it was depending on the phase angle i think been a long time ive done it, do ou think i can use this priciple with a single phase motor that is monitor the phase via an opto coupler fed to a pic and the pic drive an optocoupler to drive a triac by pwm?, my pump is is rated 0.5hp my problem is that i have installed a pump for my bathroom and the maximum pressure for my shower heater is 3 bars and my pump is working at 4 bars, the main problem i fear is that the pipes in my shower get damaged quickly and secondly the frequent start of the automatic pump will damage the stator of my motor.

thanks in advance
shailesh

[samir]

does somone have an idea of how to do a control of an induction single phase motor , i ve done one project in my course but it was for three phase, it was depending on the phase angle i think been a long time ive done it, do ou think i can use this priciple with a single phase motor that is monitor the phase via an opto coupler fed to a pic and the pic drive an optocoupler to drive a triac by pwm?, my pump is is rated 0.5hp my problem is that i have installed a pump for my bathroom and the maximum pressure for my shower heater is 3 bars and my pump is working at 4 bars, the main problem i fear is that the pipes in my shower get damaged quickly and secondly the frequent start of the automatic pump will damage the stator of my motor.

thanks in advance
shailesh

It is simple phase control ckt used in home fan regulator using PUT amd TRIAC

[zuisti]

And my proposition is an additional soft-start circuit with an R-C and an Si-diode ...

[scubadoo]

use a dimmer switch to control single phase induction motor....works on the phase shifting principal

[_Legolas]

... and the pic drive an optocoupler to drive a triac by pwm?

Not exactly, if it's not a reversed pwm and synchronized with the zero-crossing AC line.


For the first problem, if the single-phase AC motor is a PSC motor and the load is a pump/fun, you can implement a sensor-less closed-loop RPM control monitoring the RMS voltage across the motor, that only in these cases, will track (within 6%) with the speed of the pump/fun (RPM). Practically the microcontroller provides a non-linear phase-angle control to keep the speed changes linear. At this point, you can reduce the pressure pump from 4 to 3 bars.

For the second problem you need to implement a feature of soft-starting by microcontroller, creating a RPM ramp that start from a "boost" value and ends to a desired value in a certain time.

[microkid]

Hi

I think i saw a material of same spec in PIC site.

Try searching in google with PIC in front

Regards
MicroKid

Sorry I have no time to search