I have made a control algorithm which gives me reference direct voltage and reference quadrature voltage for my developed system.I wish to to calculate required value for modulation index "m" to obtain 1 pu generated voltage by the converter.
I did a normal google search and came across the formula
m=Vnom * 2*sqrt(2/3) / Vdc
http://maxwellsci.com/print/rjaset/v6-748-753.pdf (given in the matlab model of the paper..Pg 4)
From where is this formula obtained and what is the logic behind this ?
In matlab model power_wind_type_4_det.mdl I again came across this conversion.I am attaching a screenshot of same for reference
In Space Vector Modulation (SVM), I think modulation index is not important and just a way to connect with conventional PWM method. In SVM, you only need the information of magnitude, phase angle of space voltage vector and dc link voltage. Then you can compute the duty cycle for each channel and control the converter easily. The p.u unit is just a way to express the unit in standard range, just divide output voltage by nominal one. I think you can do it by yourself instead of trying to understand this example.
http://scholar.lib.vt.edu/theses/available/etd-2798-1216/unrestricted/chap2.pdf
The above mentioned formula is correct. You have to choose the appropriate value of Vdc, nominal voltages then apply SPWM/ SVPWM technique to get 1pu. While using the technique , make sure that all the design parameters are in pu.
From where do we get this formula?Could you please suggest some reference.
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