Patent ID: 8149603

Claim:
A resonance circuit for DC-link voltage control in a DC-to-AC inverter, comprising: two active switches; a coupled inductor comprising two windings; an inductor; five passive switches; and three capacitors; wherein, a first active switch of the two active switches has a positive terminal connected in series with a positive terminal of a first capacitor of the three capacitors and a negative terminal connected in parallel with a negative terminal of a first passive switch of the five passive switches, a positive terminal of the first passive switch is connected with a negative terminal of a second passive switch of the five passive switches and one terminal of the second capacitor, a positive terminal of the second passive switch is connected with one terminal of the inductor, while the other terminal of the inductor is connected in parallel with a negative terminal of the first capacitor, a positive terminal of a third passive switch of the five passive switches is connected with the positive terminal of the first passive switch, the negative terminal of the second passive switch and one terminal of the second capacitor, while a negative terminal of the third passive switch is connected in parallel with the other terminal of the second capacitor, a negative terminal of a primary side of the coupled inductor and one terminal of a second active switch of the two active switches, the other terminal of the second active switch is connected with a negative terminal of the first capacitor, the negative terminal of the first active switch is connected with a positive terminal of the primary side and a negative terminal of a secondary side of the coupled inductor, a positive terminal of a fourth passive switch of the five passive switches is connected with the negative terminal of the first capacitor after a positive terminal of the secondary side of the coupled inductor is connected with a negative terminal of a fourth passive switch of the five passive switches, a positive terminal of a fifth passive switch of the passive switches is connected with the negative terminal of the first capacitor after a third capacitor of the three capacitors is connected in parallel with the fifth passive switch, and a negative terminal of the fifth passive switch is connected with the negative terminal of the first active switch.