| 摘要 |
Provided is a switching power-supply device capable of balancing a plurality of converter blocks operated in parallel. The switching power-supply device includes a first series circuit of first and second switching elements, a second series circuit of third and fourth switching elements, which circuits are connected in parallel with a power supply, and a control circuit that turns on-and-off the first and second switching elements, alternately, with an arbitrary frequency and turns on-and-off the third and fourth switching elements, alternately, with the same frequency as the arbitrary frequency. The control circuit controls a phase difference of switching signals of the first and second series circuits. |
| 主权项 |
1. A switching power-supply device comprising:
a plurality of converter blocks each of which includes:
a series resonance circuit comprising: a transformer having a primary coil and a secondary coil that is magnetically coupled with the primary coil; a first series circuit of a first switching element and a second switching element, a capacitor that is connected to one end of the second switching element, and the primary coil that is connected between the capacitor and the other end of the second switching element, anda rectification circuit connected to a secondary coil,wherein the first series circuit being connected in parallel with a direct-current power supply, a smoothing circuit to which the rectification circuit of each of the converter blocks is connected; a control unit that controls a switching operation of the first series circuit of alternately turning on-and-off the first switching element and the second switching element with dead time in which the first switching element and the second switching element are turned off, for each of the converter blocks; and a current detection unit that detects currents flowing in each of the converter blocks, wherein at least one of the converter blocks further comprises: a second series circuit of a third switching element and a fourth switching element connected to the direct-current power-supply; and a reactor that is connected between a connection point of the third switching element and the fourth switching element and a primary coil-side terminal of the capacitor, and wherein, for each of the converter blocks having the second series circuit and the reactor, the control unit: performs controlling of a switching operation of the second series circuit of turning on-and-off the third switching element and fourth switching element, alternately, with dead time in which the third and fourth switching elements are turned off, to be the same as a frequency of switching operation of the first series circuit; and controls a phase difference between the switching operation of the first series circuit and the switching operation of the second series circuit, based on a difference between current flowing in the converter block, which is detected by the current detection unit, and current flowing in another converter block. |
