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Hello,
Recently I have successfully designed a 3 phase pulse width modulated DC-AC power source using PIC18F4431 micro controller and Power Controlled PWM (PCPWM) scheme. Now I want to compare its output voltage (phase voltage or line voltage) level with expected theoretical value. But I am...
Reducing duty cycle values is reducing the magnitude of sine wave. But the waveform is getting a dc shift. Why is that?
For lower lower % of 2^10.2877 the DC shift is even more
Fixed Vbus = 96v
I can always reduce the duty cycle value from 1225 (all other duty cycle values as well). Right?
Did you calculate the duty cycle in excel sheet or with the help of some sine look up table generator like SMARTSINE?
Code is same as before. Output voltage level can be varied by varying modulation index. Is it possible to vary modulation index in open loop configuration?
And also in PCPWM which register controls these voltage or freq modulation index?
I am designing a 3 phase DC-AC inverter with PIC18F4431. But I am having difficulties while changing voltage level at the inverter output. I am using PCPWM. How to vary the modulation index ?
The circuit I used (Inverter output filter may be different) and waveform I got are as follows:
Is it explained in the Data sheet? (Page no?)
Whats wire got to do with this?
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Probe was connected between marked terminals and the ground probe was properly set before connection
In this PWM out put waveform (whic is collected from pin PWM0 of a PIC18F4431) there is a 0.2 volt drop below zero in the pwm output waveform. In the output waveform of the PWM I see that there is a +5v rise during ON period. But also there is a -0.2 volt fall during OFF period. Whts the reason...
Hello everyone,
I am designing a variable frequency output 3 phase inverter using PCPWM mode of PIC18F4431. But I am having difficulties in finding modulation indices(voltage and freq). Also in PCPWM which register controls the carrier wave and which register controls...
I have some questions:
1> Why did you divided PDCxH by 2^8
2> What is the purpose of : int argc and char** argv in int main( int argc and char** argv)
3> and why did you use:
asm("CLRWDT")
...
while(1){
asm("CLRWDT")
}
4) If I use different PR2 value if I want different set of frequency?
5> I...
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