The present disclosure generally relates to the field of power supply systems, and more particularly to a multiple power source power supply.
Electrical energy in the form of Alternating Current (AC) is a commonly available power source found in buildings, including homes. AC power is typically supplied by a central utility via power lines or from a physical plant that is part of a facility. However, many common devices, including electronic circuits and DC motors, utilize electrical energy in the form of Direct Current (DC), which is electrical current that flows in only one direction. Thus, it is often desirable to convert AC power to DC power.
Power supply systems convert AC power to DC power suitable for powering electrical components, also known as a load. It is often desirable to combine multiple redundant power supplies in parallel to supply a given load requirement. When power supplies are combined in parallel, the output of each power supply may be combined to produce a shared output, or common output load. When multiple power supplies are combined in parallel, reliability and efficiency for the power supply system may be improved. Redundant parallel-connected power supplies may increase reliability for the overall power supply system whereby a failure of a power supply will cause other power supplies to supply enough current for support of a maximum load.
Multiple power supplies combined in parallel typically operate at a light load during their normal operation and thus may operate at poor efficiency. Additionally, each power supply of a redundant pair of power supplies are typically a full capacity power supply operable to handle a total load, which causes a power requirement overcapacity and increases a total cost of the power supply system.
Accordingly, the present disclosure is directed to a multiple power source power supply. In one embodiment, a multiple power source power supply may include multiple power inputs fed by separate power sources. A multiple power source power supply may also include multiple electromagnetic interference (EMI) filters, multiple rectifier bridges and multiple power factor correction controllers. A multiple power source power supply may include a single converter that may supply a stable voltage to a load. In an embodiment, a plurality of multiple power source power supplies may be combined to operate in parallel and provide a cost and energy efficient power supply system.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not necessarily restrictive of the present disclosure. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate subject matter of the disclosure. Together, the descriptions and the drawings serve to explain the principles of the disclosure.
The numerous advantages of the disclosure may be better understood by those skilled in the art by reference to the accompanying figures in which:
Reference will now be made in detail to the subject matter disclosed, which is illustrated in the accompanying drawings.
Referring to
Referring to
First PFC circuitry 218 may include an electromagnetic filter 220, a rectifier bridge 230 and a power factor correction controller 240. Second PFC circuitry 219 may include electromagnetic filter 225, a rectifier bridge 235 and a power factor correction (PFC) controller 245. Electromagnetic interference (EMI) filter 220 may be coupled to input 210 and electromagnetic interference filter 225 may be coupled to input 215. Bridge rectifier 230 may receive an output of the EMI filter 220. Bridge rectifier 235 may receive an output of EMI filter 225. Power factor correction controller 240 may be coupled to bridge rectifier 230 while power factor controller 235 may be coupled to bridge rectifier 235. The output of PFC controllers 240, 245 may be combined and supplied to a single converter 250.
The output of PFC controllers 240, 245 may be coupled to an OR diode circuit or similar device for combining redundant power providers, the output of the OR diode circuit being coupled with converter 240. OR diode circuit may provide isolation for power supply 200 and may prevent reverse current flow within power supply 200. OR diodes may be a conventional diode and may be a Schottky diode. In another embodiment, OR diodes may be implemented with a field effect transistor and a driver. For example, OR diodes may be implemented as a body diode of a transistor, such as a MOSFET, whereby the transistor is turned on, shunting the body diode with a very low voltage drop when the current is moving through the body diode. Output 260 may be coupled to converter 250 and may supply a voltage to a load.
Power supply 200 may operate to provide reliable power through operation of a backup power source, such as a second AC power source. For example, first PFC circuitry 218 may provide the DC output to converter 250 when the first AC power source is operable. However, second PFC circuitry 219 may provide the DC output to converter 250 when said first AC power source is un-operable. In this instance, second AC power source may supply power to second input which is received by second PFC circuitry 219.
Referring to
Additionally, power supply systems, including power supply system 300, may include current sharing circuitry. Current sharing circuitry may ensure that each power supply of a multiple power supply system may equally, or approximately equally, supply current to the load. For example, two power supplies may share the current within 10% of its full load current. If the maximum rated output current of an output is 50 amperes (A), then the difference between two or more supplies may be within 5 A.
When power supplies operate at light loads (for example, 20% of full load) current sharing accuracy decreases. Through employing current sharing, a first power supply may operate 17.5% of its rated power while a second power supply may operate at 22.5% of its rated power. Referring to
Referring again to
OR diode circuit may provide isolation for power supplies 310-330 and may prevent reverse current flow within power supplies 310-330. OR diodes may be a conventional diode and may be a Schottky diode. In another embodiment, OR diodes may be implemented with a field effect transistor and a driver. For example, OR diodes may be implemented as a body diode of a transistor, such as a MOSFET, whereby the transistor is turned on, shunting the body diode with a very low voltage drop when the current is moving through the body diode.
Multiple power source power supplies 310-330 may be in communication with each other such that, if one power supply should fail, the other power supplies may supply the full load. It is contemplated that power supplies 310 may employ current sharing circuits. If one power supply fails, the other power supplies may automatically adjust their output current for the same total output current to the common load. Additionally, each power supply 310-330 may be supplied by multiple AC power sources 350, 352. If a first AC power source 350 should fail, a second AC power source 352 may supply power to the power supplies 310-330 which may supply a desired output voltage and power to output bus 340.
Operation of power supply system 300 may result in additional cost savings. In the example of a 1000 Watt power supply system, three multiple power source, 500 W, power supplies may supply power at 11 cents/watt, or $55.00 each for a total of hardware costs of $165.00, less than the $200.00 cost of two 1000 watt, single input power supplies. Additionally, the operating cost may be reduced through greater operating efficiency of each power supply. In the example of a system load of 400 W, an ideal current sharing by each power supply 310-330 may operate at 133 W which is 27% of a maximum load of 500 W. When each power supply is operating at 27% of the maximum load of 500 W, each power supply may operate at 82% efficiency as shown in
It is contemplated that power supply system 300 may be employed with information handling systems, such as computing systems of a data storage system and/or storage rack, shelf and the like. Data storage systems require reliable power to ensure valid read and write access to data on a continuous basis. Power supply system 300 may ensure a reliable power delivery to the data storage system.
Additionally, computing systems and data storage systems that comprise a data center consume a significant amount of power. Since there is a demand for constant access to data, there is an inability to reduce power through reduced consumption. Consequently, power efficiency is desirable. Power supply system 300 may provide reduced power loss through higher operating efficiency while providing a reliable power supply system. A data storage system employing a power supply system 300 of the present invention may increase reliability of the data storage system while reducing power consumption and cost. Power supply system 300 may be modified to employ a number of multiple power source power supplies greater than three for additional flexibility.
Referring to
Method 500 may further include detecting a failure of a first power source of multiple power sources to the first multiple power source power supply, second multiple power source power supply and third multiple power source power supply 530. Method 500 may include supplying a combined output of the first multiple power source power supply, second multiple power source power supply and third multiple power source power supply to a data storage system by utilizing a second power source of multiple power sources 540.
Method 500 may further include detecting a failure of a multiple power source power supply 550. In response, method 500 may include adjusting output of two operating multiple power source power supplies to supply the common output to the data storage system and maintain operation of the data storage system despite the failure of a power supply. It is contemplated that method 500 may allow data storage system to remain reliably operable even in the case of a power source failure or a power supply failure. Additionally, method 500 may be executed in a power efficient manner with the use of multiple power source power supplies 200 as shown in
It is believed that the system of the present disclosure and many of its attendant advantages will be understood by the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the components without departing from the disclosed subject matter or without sacrificing all of its material advantages. The form described is merely explanatory, and it is the intention of the following claims to encompass and include such changes.