sooyassine1
Newbie level 6
Hi,
I'm designing an LC filter for a 3 phase sine wave inverter (7KVA 230V 50Hz) , my inverter is controlled by an SPWM, there are my output quality specifications : THDi<3% & THDv<3% .
I ve calculated the cut off frequency in order to attenuate the first significant harmonic which appears on the carrier frequency(6150Hz), the gain of this harmonic is about 40dB , so with a 2nd order filter i should cut off at 615Hz.
but i see that it s not the good way to find the cut off frequency , because it don't take on consideration the specifications of THDi & THDv.I can do that only on simulation!!! I want to know if there is a method or a document which can help me in this topic
I'm designing an LC filter for a 3 phase sine wave inverter (7KVA 230V 50Hz) , my inverter is controlled by an SPWM, there are my output quality specifications : THDi<3% & THDv<3% .
I ve calculated the cut off frequency in order to attenuate the first significant harmonic which appears on the carrier frequency(6150Hz), the gain of this harmonic is about 40dB , so with a 2nd order filter i should cut off at 615Hz.
but i see that it s not the good way to find the cut off frequency , because it don't take on consideration the specifications of THDi & THDv.I can do that only on simulation!!! I want to know if there is a method or a document which can help me in this topic
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