This application claims the foreign priority benefit under 35 U.S.C. Section 119 of Korean Patent Application Serial No. 10-2013-0131194, entitled “Power Supply Apparatus” filed on Oct. 31, 2013, which is hereby incorporated by reference in its entirety into this application.
1. Technical Field
The present disclosure relates to a power supply apparatus, and more particularly, to a power supply apparatus capable of improving energy efficiency under a low load that is a half load or less.
2. Description of the Related Art
As energy consumption becomes a social issue, more attention is paid to energy conversion efficiency. In particular, energy efficiency is especially important for server power and thus it is necessary to factor server power technology and an essential factor to consider in order to enter the server market. For example, in the case of CSCI-titanium, for a load of 10%-20%-50%-100%, high efficiency of 90%-94%-96%-91% is required. It is especially difficult to improve efficiency under a half load or less, and there is an increasing demand for high efficiency under a very low load of 10% or less. Incidentally, some server power supplies commonly have a redundant structure in which several power supplies are connected to one load in order to cope with various faults. In this case, efficiency under a low load condition may be increased by performing a cold redundant control that operates a master circuit part only when load becomes smaller. Even in this manner, however, efficiency is not improved more than that of a single module, and it is difficult to improve efficiency under a very low load.
An object of the present teaching is to provide a power supply apparatus capable of improving energy efficiency under a low load that is a half load or less.
According to an exemplary embodiment, there is provided a power supply apparatus, including a master circuit part charging a battery initially, supplying energy to a load that is a light load, and charging the battery when discharged; and a slave circuit part having a common output terminal with the master circuit part and supplying energy to the load that is a heavy load along with the master circuit part by distributing the load among them, wherein the master circuit part includes a rechargeable battery therein.
The master circuit part may further include an initial battery charger for charging the battery initially.
The initial battery charger may include a transformer receiving AC voltage and generating output voltage having an amplitude different from that of input voltage according to a turns ratio between primary and secondary windings; a switch element producing intermittent current flowing in the primary winding of the transformer; and a diode for rectifying AC voltage induced in the secondary winding of the transformer into DC voltage. The switch element may be a MOSFET.
The initial battery charger may include an AC/DC converting unit that receives AC voltage from an AC voltage source and converts it into a DC voltage; a transformer that converts the DC voltage converted by the AC/DC converting unit into DC voltage having a different amplitude according to the turns ratio between the primary and secondary windings; and a rectifying unit rectifying an AC component mixed in the DC voltage induced in the secondary winding of the transformer into a DC component.
The power supply apparatus may further include an inductor that removes a high-frequency noise component mixed in current supplied to the battery through the rectifying unit.
The AC/DC converting unit may be configured as a full bridge circuit that includes a first switch element with its one terminal connected to the AC voltage source; a first diode connected to the first switch element in series, a second diode connected to the first switch element in parallel, and a second switch element connected to the second diode in series. The first and second switch elements may be MOSFETs.
The rectifying unit may be configured as a half bridge circuit that includes a first output diode connected to one terminal of the secondary winding of the transformer in series, and a second output diode connected to a unit circuit consisting of the secondary winding and the first output diode in parallel.
The master circuit part may be configured to supply energy to a load that is a half load or less.
The slave circuit part may be configured to supply power for charging the battery if a voltage of the battery is a reference voltage or less.
Terms and words used in the present specification and claims are not to be construed as a general or dictionary meaning, but are to be construed as meaning and concepts meeting the technical ideas of the present invention based on a principle that the inventors can appropriately define the concepts of terms in order to describe their own inventions in the best mode.
Throughout the present specification, unless explicitly stated otherwise, “comprising” any components will be understood to imply the inclusion of other elements rather than the exclusion of any other elements. The terms “part,” “module,” “device” or the like used in the specification means a unit of processing at least one function or operation and may be implemented by hardware or software or a combination of hardware and software.
Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.
Referring to
The master circuit part 110 charges a battery initially, supplies energy to a load that is a light load, and charges a discharged battery. In the master circuit part 110, a rechargeable battery 112 is provided. Further, the master circuit part 110 includes a buck converter unit 113 for supplying energy to a load that is a half load or less in a normal operation state and charging the battery 112 when it is discharged. Here, the buck converter unit 113 may be a bidirectional synchronous buck converter (BSBC).
The slave circuit part 120 has a common output terminal with the master circuit part 110 and supplies energy to the load that is a heavy load along with the master circuit part 110 by distributing the load among them. The slave circuit part 120 is configured with a phase-shift full bridge (PSFB) and VA
The master circuit part 110 may further include an initial battery charger 111 for charging the battery 112 initially.
As shown in
According to another exemplary embodiment, the initial battery charger 111 may be configured as shown in
In addition, the AC/DC converting unit 111a may be configured as a full bridge circuit that includes a first switch element Q1 with its one terminal connected to the AC voltage source, a first diode D1 connected to the first switch element Q1 in series, a second diode D2 connected to the first switch element Q1 in parallel, and a second switch element Q2 connected to the second diode D2 in series. The first and second switch elements Q1 and Q2 may be MOSFETs. Again, as will be appreciated, the first and second switch elements Q1 and Q2 may be bipolar transistors.
In addition, the rectifying unit 111b may be configured as a half bridge circuit that includes a first output diode Do1 connected to one terminal of the secondary winding Ns of the transformer T2 in series, and a second output diode Do2 connected to a unit circuit comprising the secondary winding Ns and the first output diode Do1 in parallel.
Further, the master circuit part 110 is configured to supply energy to a load that is a half load or less.
Further, the slave circuit part 120 is configured to supply power for charging the battery 112 if the voltage level of the battery 112 is at a reference voltage level or less.
Hereinafter, the operation of the power supply apparatus thus configured according to an exemplary embodiment will be described.
Initially, the battery 112 is charged by the initial battery charger 111 as shown in
As described above, the power supply apparatus according to the present disclosure includes the rechargeable battery in the master circuit part of a power supply circuit such that energy is supplied to a load using the battery being a low load that is a half load or less, thereby increasing energy efficiency.
Although the exemplary embodiments of the present invention have been disclosed for illustrative purposes, the present invention is not limited thereto, but those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Therefore, the true scope of the present invention to be protected should be defined only by the appended claims and it is apparent to those skilled in the art that technical ideas equivalent thereto are within the scope of the present invention.
Number | Date | Country | Kind |
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10-2013-0131194 | Oct 2013 | KR | national |