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Delay on execution

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Hello, I am new on this forum and also new into the NI Labview world, I hope to be helpful in the future but first, I need some help with many things.

 

First problem is, I have a project on Labview 2012 which I execute using a host that calls a FPGA vi with the FPGA interface, thing is my program takes around 2-4 miliseconds to execute. What do I mean by this? I will explain. 

 

The project I am working on, is to activate some TRIACs that are on an AC 240V three phase line (each line has a TRIAC, so there are 3 TRIACs)  by having output pulses from the module NI 9263 so I can vary an output DC voltage at a rectifier bridge of the three phase. The zero crossing I get it by measuring the three phase current of each line with the NI 9227 and the output voltage feedback I  monitore it with the module NI 9215 (max DC voltage around 18.5 volts, using a resistor tu get max 6.54 DC voltage on the NI 9263 and vary voltage from that reference). The program runs with a FPGA PID in order to control the firing angle depending of the set point voltage I want/need

 

Now, my two issues right now are:

 

1.- Regardless what angle I get, it always start sending signals at 2.3 - 4.2 ms from the zero cross, In other words, my program starts shooting at 60-90 degrees thinking it is at the exact zero cross. since I am having this delay, I cannot fire in the first 0 - 90 degrees and I am not sure why it is having such delay.

 

2.- I think this is more of a hardware issue but still, once the program fires a pulse to the optocouple to activate the TRIAC, the sinusoidal signal of each three phase line doesn't cuts. it starts to cut after 1 semicicle and with a lot of noise.

 

I attach the project in a zip file for a labview 8.6 version. any other information needed please let me know. 

 

PS: I haven't had any time to take a course, so I have been learning all ober by myself with examples from the Labview example list and the material I have found on NI. In advance Thanks, and sorry for the messy code. 

 

 


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