Why using SVPWM method for three-phase inverter, output sine wave frequency and calculation is always inconsistent???????
Below is about the SVPWM code:


Double t1, t2, t3,//the adjacent two vector and zero vector
Double pwm1=0, pwm2=0, pwm3=0;//each phase of the switch tube conduction time
If (TIM3 - & gt; CR1 & amp; 0 x0010 x0010==0)//the central counting mode determine whether for counting down
{
If (t>=360) t=0;
If (t>=0 & amp; & T<=60)
{
T1=M * sin_num [t] - 60/F;//F each conduction cycle time, use will be lose
T2=M * sin_num [t]/F;
1/F - t1, t2, t3=;
Pwm1=t1 + t2, t3/2;
Pwm2=t2 + t3/2;
Pwm3=t3/2;
}

Else if (t> 60 & amp; & T
=120){
T1=M * sin_num] [120 - t/F;
T2=M * sin_num [60] t -/F;
1/F - t1, t2, t3=;
Pwm1=t1 + t3/2;
Pwm2=t1 + t2, t3/2;
Pwm3=t3/2;
}
Else if (t> 120 & amp; & T
=180){
T1=M * sin_num] [180 - t/F;
T2 * sin_num=M/t - 120/F;
1/F - t1, t2, t3=;
Pwm1=t3/2;
Pwm2=t1 + t2, t3/2;
Pwm3=t2 + t3/2;
}
Else if (t> 180 & amp; & T
=240){
T1=M * sin_num] [240 - t/F;
T2 * sin_num=M/t - 180/F;
1/F - t1, t2, t3=;
Pwm1=t3/2;
Pwm2=t1 + t3/2;
Pwm3=t1 + t2, t3/2;
}
Else if (t> 240 & amp; & T
=300){
T1=M * sin_num] [300 - t/F;
T2 * sin_num=M/t - 240/F;
1/F - t1, t2, t3=;
Pwm1=t2 + t3/2;
Pwm2=t3/2;
Pwm3=t1 + t2, t3/2;
}
Else if (t> 300 & amp; & T
=360){
T1=M * sin_num] [360 - t/F;
T2 * sin_num=M/t - 300/F;
1/F - t1, t2, t3=;
Pwm1=t1 + t2, t3/2;
Pwm2=t3/2;
Pwm3=t1 + t3/2;
}
TIM3 - & gt; CCR1=(pwm1) * F * COUNT;
TIM3 - & gt; CCR2=(pwm2) * F * COUNT;
TIM3 - & gt; CCR3=(pwm3) * F * COUNT;
T +=6;

} each step 6 degrees
This part is placed in the interrupt service function to



The question is: why in addition to each step 1 degree of calculated value and actual value of the same frequency, calculation step of progress after several other will make the output frequency of 100 hz or so

And the output waveform will sometimes have a rush up and down, please bosses to address the problem