Power factor correction device and apparatus for converting a three-phase alternating current into a direct current
A power factor correction device includes a power supply side which can be connected to an alternating current source, an output side which can be connected to a direct current load, at least a first power inductor electrically connected in series to a first terminal of the power supply side, and a rectifier operatively interposed between the power supply side and the output side. The rectifier includes a diode bridge configured to convert the alternating current from the source into a direct current towards the load, and one or more switches which can be selectively switched between an open configuration and a closed configuration in order to switch the rectifier between a first configuration, in which it interrupts the current flow towards the output side and charges the first inductor, and a second configuration, in which it allows the transfer of current to the load and discharges the first inductor. A second power inductor is electrically connected in series to a second terminal of the power supply side.
1 . A power factor correction device comprising:
a power supply side which is connectable to a source of alternating current, the power supply side including at least a first terminal and a second terminal, which are connectable to a phase and to a neutral of said source, respectively;
an output side which is connectable to a direct current load and which includes a positive voltage terminal and a negative voltage terminal;
at least a first power inductor electrically connected in series to said first terminal of the power supply side;
a rectifier operatively interposed between said power supply side and said output side and comprising:
a diode bridge configured to convert the alternating current into a direct current towards the load;
one or more switches which are selectively switchable between an open configuration and a closed configuration to switch the rectifier between a first configuration, in which said rectifier interrupts a current flow towards the output side and charges said first power inductor, and a second configuration, in which said rectifier allows the current flow to the load and discharges said first power inductor;
a second power inductor electrically connected in series to said second terminal of the power supply side;
wherein said first power inductor and said second power inductor are magnetically coupled to each other such that the current flowing in the first power inductor flows in a same direction as a current flowing in the second power inductor.
2 . The device according to claim 1 , comprising:
two of the first power inductor connected together in series,
two of the second power inductor connected together in series,
wherein one of said first power inductors and one of said second power inductors are magnetically coupled to each other.
3 . The device according to claim 1 , wherein the first power inductor and the second power inductor, which are coupled together, are concentrically wound around a same ferromagnetic core.
4 . The device according to claim 1 , wherein said rectifier has one of the following configurations:
Vienna,
Totem pole.
5 . An apparatus for converting a three-phase alternating current into a direct current, comprising:
three devices according to claim 1 ,
wherein the source of alternating current is a source of three-phase alternating current;
wherein the three devices are arranged in parallel, with each having:
the first terminal of the power supply side connected to a respective phase of the three-phases of the source;
the second terminal of the power supply side connected in parallel with the other second terminals and to the neutral of the source;
the positive voltage terminal of the output side connected in parallel with the other positive voltage terminals to form a positive voltage branch;
the negative voltage terminal of the output side connected in parallel with the other negative voltage terminals to form a negative voltage branch.
6 . The apparatus according to claim 5 , and further comprising a charging stage operatively arranged downstream of said three devices and connected to said positive voltage branch and said negative voltage branch; said charging stage comprising a capacitor bank configured to be charged when said rectifier is in said second configuration.
7 . The apparatus according to claim 6 , wherein the capacitor bank includes at least two capacitors connected in series and between which a central tap is interposed; said second terminals of the power supply side of the devices being connected to the central tap of the capacitor bank.