03-24-2014 08:25 PM
Hi,
i am working on developing a synchro simulator using NI 9269 in LV 2012. according to theory synchro is a three wire signal S1 S2 S3 with reference voltage R1 R2. at first i am using 26 V 400 Hz refernce. the equations i am implementing are as follows;
S1= - sqrt (2) * (11.8)* sin (theta + 60) * sin(wt) eq (1) w= ref signal frequency 11.8 = rms value for output , theta= the angle
S2= - sqrt (2) * (11.8) * sin (theta) * sin (wt) eq(2)
S3= - sqrt (2) * (11.8)* sin (theta + 120) * sin(wt) eq (3)
i am geenrating the signals as single ended output , using three outputs A0 ,A1 a,nd A2 of NI 9269.
as per the theroy i got from public domain literature it is stated that theta is the angle we want to sent over the signlas S1 S2 S3 such that the signals are some 120 part or phase shift. the LINE - LINE voltage required should be
Voltage (S3 -S1) = (constant value) * sin(wt) * sin (theta)
Voltage (S3 -S2) = (constant value) * sin(wt) * sin (theta+120)
Voltage (S2 -S1) = (constant value) * sin(wt) * sin (theta+240)
i implemnted eq (1) (2) and (3) in FPGA and generate the signals from NI 9269. i use a reference signal 26 V , 400 Hz from synchro reference signla generator.
BUT when i connect all above ono an angle position indicator (API) , It shows me erronous result .
i fixed the synchro angle theta value equal to 15 degree and API should display 15 Degree but it is not happing and it is showing fluctuating results like 100 degree 115 , 89, 67 etc.
how i achive the correct angle position on API and what changes should i made in my equations etc to achive it.
Regards
03-25-2014 09:42 AM
Tirmizi,
This board is more catered towards NI 54xx products. Please post this on the Multifunction DAQ discussion board, or even the cRIO board if you are using a cRIO device.
http://forums.ni.com/t5/Multifunction-DAQ/bd-p/250
http://forums.ni.com/t5/Real-Time-Measurement-and/bd-p/280
Regards,
Jason L.