In order to perform this analysis we suppose that the current or the currents absorbed by the load are sinusoidal, of the same period with the voltages applied by the inverter.

This hyphotesis supposes the neglection of the currents' harmonics.

We are asked to obtain the decomposition in Fourier series of the current at the input of the inverter by realizing a power balance, supposing that the semiconductor switches are ideal (voltage drop zero in the ON state, residual current zero in the OFF state, instantaneous commutations) so that the instantaneous value of the power at the input of the inverter is equal to the instantaneous value of the power absorbed by the load.

Single-phase inverter application

• If

  express as a sum of terms in sin and cos and determine the amplitude of the pulsatory component

 

Tri phased inverter application

• If

  express as a sum of terms in sin and cos and determine the amplitude of the pulsatory component