How to add delay time for motor(inverter) start?

[yzou_ua]

With dc voltage present, my PWM signals cannot be given to the inverter. I guess this is buz my initial PWMs are inducing a over current so the inverter turn them off. So, I have to run the PWM 1st and then turn on the dc.

So, my solution is to add a delay to dc voltage inside of code. My question is WHERE to add? - "while()" loop? or elsewhere? Pls give some examples code to follow. Thx a lot!!

 

[suvaraj]

send ur coding

 

[Tahmid]

You have to add the delay at the beginning of the code before the while() loop. In the while() loop, you carry out actions that are to be infinitely repeated and the delay is not to be infinitely repeated, instead to be added at the beginning of the code, to be carried out once after the PIC starts / restarts.

What I think you should do is add a soft-start and not just a delay. So, you should have the DC from the start. However, apply the PWM slowly with increasing duty-cycle. So, you can start from 0% duty-cycle, ie full-off. And slowly increase the duty-cycle.

Have you also ensured that the current rush isn't due to bulk capacitor charging to maximum capacity?

Hope this helps.
Tahmid.