praveen_palaparthi
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Hi friends i am doing single phase sinusoidal PWM inverter using micro controller.I have generated sine wave at output using sine table.My controller is pic 16f886 output frequency is 50Hz,and swicthing frequency is 20Khz and output at no load is 250 volts rms.I used PWM modules in the controller to generate SPWM.
My problem is when i am switching the load of 200W bulb its output voltage is decreasing to 200V rms.How to correct this voltage.Theory says that by changing modulation index Ma=Ar/Ac Ar=peak amplitude of reference wave,Ac peak amplitude of carrier wave,we can get varaible volta ge but how to implement this in code.I mean how to correct(increase or decrease) the duty cycle.I know by using PI tuning we can get but i dont know how to implement i am not getting the logic can anybody help to get the logic.
can anybody give examples code for this to correct duty cycle using PID tuning
Hi friends i am doing single phase sinusoidal PWM inverter using micro controller.I have generated sine wave at output using sine table.My controller is pic 16f886 output frequency is 50Hz,and swicthing frequency is 20Khz and output at no load is 250 volts rms.I used PWM modules in the controller to generate SPWM.
My problem is when i am switching the load of 200W bulb its output voltage is decreasing to 200V rms.How to correct this voltage.Theory says that by changing modulation index Ma=Ar/Ac Ar=peak amplitude of reference wave,Ac peak amplitude of carrier wave,we can get varaible volta ge but how to implement this in code.I mean how to correct(increase or decrease) the duty cycle.I know by using PI tuning we can get but i dont know how to implement i am not getting the logic can anybody help to get the logic.
can anybody give examples code for this to correct duty cycle using PID tuning