Inverter DC Capacitor Voltage Control

Using PI to control the DC capacitor voltage of the inverter, but there are pulses from 0.4 seconds. I don't know what the cause is.

[Sam Chak]

Do you have the mathematical model of the DC capacitor voltage of the inverter?

Answer 1

[Zuber Khan]

Hi,

I understand that receiving pulsating DC capacitor voltage is not a normal behaviour in case of an inverter. Since you have neither shared the mathematical model nor the Simulink model, it is difficult to find the exact reason behind this issue.

However, there are some general troubleshooting steps as follows that you can try at your end:

1) Check if you are correctly tuning the PI Controller parameters. Improper tuning of the PI controller parameters (proportional gain (K_p) and integral gain (K_i)) can lead to instability or oscillations.

2) Analyze the step response of your system with the PI controller to ensure it is stable and meets required performance criteria.

3) Conduct a frequency response analysis to spot any resonant frequencies that might be causing the oscillations.

4) Run simulations of your system under different conditions. This can help you pinpoint the cause of the pulses and fine-tune the controller parameters accordingly.

5) Make sure your system model accurately reflects the real-world system, including any delays and non-linear characteristics.

I hope it helps.

Regards,

Zuber