As per my understanding, you are trying to design an "LCL filter" for an induction machine, driven by an inverter. I want to add some suggestion based on my understanding. The "LCL filter" are more commonly used for grid connected inverters because the inductance of a stiff grid is very less and you cannot directly connect a capacitor across a stiff voltage source. In an induction machine, the leakage inductance is relatively significant and effectively functions as the second inductor. Therefore, only "LC filter" is sufficient for an induction motor. You can connect "LC filter" banks across all the three phases of the motor as shown in the below Simulink screenshot.
Procedure to design a LC filter for an induction machine:
- First select the value of filter capacitor by using the below formula:
(
) is the magnetising inductance of the induction machineLm is the magnetising inductance of the induction machine
) is the magnetising inductance of the induction machineLm is the magnetising inductance of the induction machine - Then calculate the value of filter inductance using the formula:
Here, "
" value is decided by you as a design specification. Generally, it is taken as 20% of full load current.
" value is decided by you as a design specification. Generally, it is taken as 20% of full load current. You can refer to the below given research paper in order to have understanding of how the design equations are derived.
P. Mishra and R. Maheshwari, "LC filter design method for pulse width modulated inverter Fed induction motor drive," 2017 IEEE Transportation Electrification Conference (ITEC-India), Pune, India, 2017, pp. 1-6, doi: 10.1109/ITEC-India.2017.8356945.
I hope it helps !
