HIGH POWER DENSITY INVERTER (I)

摘要

The present invention relates to a single phase, non-insulated, miniaturized DC/AC power inverter (1) having an output power density higher than 3000 W/dm³, wherein said first (S1_H), second (S1_L), third (S2_H) and fourth(S2_L)switches are made of wide-band semiconductors and preferably of gallium nitride or GaN semiconductors; and wherein said DC/AC power inverter (1) further comprises : -a ripple-compensating active filter comprising a third half-bridge (203) having a fifth switch (S3_H) in series with a sixth switch (S3_L), said fifth switch (S3_H) being connected at one end to the positive terminal (L+) of the DC input, said sixth switch (S3_L) being connected at one end to the negative terminal (L-) of the DC input,the other end of the fifth switch (S3_H) being connected to the other end of the sixth switch (S3_L), defining a third common end, said third common end being connected to a first end of a LC filter, made of at least one inductor (L6) and one storage capacitor(C5), a second end of the LC filter being connected to the negative terminal (L-); -modulation control means of said first (S1_H), second (S1_L), third (S2_H), fourth (S2_L), fifth (S3_H) and sixth (S3_L) switches for providing a switch frequency comprised between 20 and 500 kHz and allowing variable phase shifts between any two of said first (201), second (202) and third (203) half- bridges and allowing dead time modulation of the switches of said half- bridges (201, 202, 203), so that to obtain a switching approaching ZVS switching, in particular to obtain switching when current crosses through zero and further to cancel switching losses and so that to allow high peak-to-peak voltage variations in the active filter, while storing corresponding energy in the storage capacitors (C5), wherein the Y-capacitors of the common mode noise filter (100). are referenced to a shielding being at a reference potential, said shielding being insulated from earth, said Y-capacitors having a value comprised between 100nF and several μF.