JP2007172108A - Power supply device, information processor, and voltage output setting method for output voltage variable power source - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To maximize power supply efficiency of a device adaptively to the operating state thereof to save the power, whereas current consumption characteristic of a logic module is fluctuated depending on the operating state of the device to fluctuate the power efficiency of the device. <P>SOLUTION: A DC-DC power source 100 changes depending on values of input voltage Vm and output current Io. Power Pi at the time of change of Vm of an AC-DC power source 2 is calculated by a control part 21 and an output current measuring part 22 provided in the power source 2, and an algorithm for operation at Vm where the power Pi is minimized is started by operating state information from an autonomous or logic module, whereby delicate optimization control is executed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a power supply apparatus, an information processing apparatus, and a voltage output setting method for an output voltage variable power supply, and more particularly to an energy saving power supply apparatus, an information processing apparatus, and a voltage output setting method for an output variable power supply.

  Conventionally, in the information processing apparatus, the power supply voltage used in the logic module has been mainly 5V. In this case, the information processing apparatus is generally provided with a primary power source that directly generates DC 5V from a commercial power source of AC 100V, and the logic module is generally configured to supply power with a DC 5V fixed voltage.

  In recent years, power supply voltages required by electronic components used in logic modules have been reduced to 3.3V, 2.5V, and 1.8V. On the other hand, it is difficult to unify the supply voltages to the electronic components. Supplying a plurality of power supply voltages from the primary power supply requires a plurality of supply wirings, which is disadvantageous in mounting. For this reason, it has become common for information processing apparatuses to have a configuration in which a DC-DC power supply is mounted on the logic module and a voltage required by the mounted electronic component is generated.

  For the above-described use, a DC-DC power supply that outputs an intermediate voltage Vm output from the primary power supply of 48 volts and outputs a voltage of 48V to 5V on the logic module is commercially available.

  Non-Patent Document 1 describes that the efficiency of a DC-DC power supply (DC-DC converter) depends on a voltage before conversion and an output current. This will be described with reference to FIGS. Here, FIG. 1 is a diagram illustrating symbols. FIG. 2 is a diagram in which the diagram described in Non-Patent Document 1 has been rewritten so as to be easy to see, and is a diagram for explaining the relationship between the output current and the conversion efficiency when the voltage before DC-DC conversion is used as a parameter.

  In FIG. 1, a combined DC-DC power supply 100 receives DC Vm volts and Ii amperes as input and converts them to DC Vo volts and Io amperes. At this time, the conversion efficiency η (eta) of the combined DC-DC power supply 100 is a function η (Vm, Io, T) depending on the input voltage Vm, the output current Io, and the operating ambient temperature T. When operating at a constant temperature Tc, this function is a function η (Vm, Io) of the input voltage Vm and the output current Io. In the following, it is assumed that the apparatus operates at a constant temperature. Note that the combined DC-DC power supply refers to a plurality of DC-DC power supplies as a single DC-DC power supply.

  In FIG. 2, the horizontal axis represents the output current, the vertical axis represents the conversion efficiency, and the input voltage is applied as a parameter. As can be seen from FIG. 2, the output current with the highest conversion efficiency depends on the input voltage. As a result, it can be seen that there is an input voltage that gives a peak of efficiency when the output current is constant at Ioc.

  Patent Document 1 describes a switching power supply that measures the output current of a DC-DC power supply. However, Patent Document 1 does not describe measuring the input current of a DC-DC power supply.

Japanese Patent Laying-Open No. 2005-312141 "PAH75D24 SERIES THERMAL DESIGN", Page 3 Figure 1-2, [online], June 7, 2002, DENSEI-LAMBDA, [November 4, 2005 search], Internet <URL: http: // www .densei-lambda.com / products / sps / ps_pm / pah-d / pdf / thermal_design_75d24.pdf>

  The DC-DC power supply is a power supply that supplies a constant output voltage even if the input voltage fluctuates slightly. However, the conversion efficiency depends on the input voltage and the output current. On the contrary, since the conversion efficiency depends on the input voltage, the input voltage can be set to a voltage for obtaining the optimum conversion efficiency.

  Among information processing apparatuses, communication apparatuses transmit and receive via a communication cable. Therefore, the operation state changes depending on the transmission / reception traffic. The change in transmission / reception traffic occurs due to the influence of the day of the week or the time of day, the influence of switching the routing control information, and the like. This change in traffic changes the current consumption condition in the logic module. This change in current consumption may be caused by a change in the activity pattern of the network user due to the influence of the day of the week or the time, or a change in route information due to a communication path failure.

  However, since the intermediate voltage Vm is fixed in the power supply configuration of the conventional communication apparatus, it is impossible to meticulously cope with fluctuations in the load pattern of the logic module.

  An object of the present invention is to obtain a power-saving power supply apparatus and information processing apparatus, and a voltage output setting method for an output voltage variable power supply.

  The above-mentioned problem is that the direct current of the intermediate voltage supplied from the alternating current to the DC-DC power supply is generated, the output current is measured while changing the value of the intermediate voltage, and the power consumption of the DC-DC power supply is determined to be small. This can be achieved by a power supply device that sets an intermediate voltage.

  In addition, the first power source includes a first power source that generates a direct current of an intermediate voltage from the alternating current and a second power source that generates a direct current of an electronic component supply voltage from the intermediate voltage, and the first power source is an output voltage that adjusts the intermediate voltage This can be achieved by an information processing apparatus including an adjustment unit and an output current measurement unit that measures the current value of the intermediate voltage.

  Furthermore, a first power source that generates a direct current of an intermediate voltage from alternating current, a second power source that generates a direct current of an electronic component supply voltage from the intermediate voltage, and an intermediate voltage of the first power source are set, and the current of the intermediate voltage A control unit that monitors the value, and the control unit monitors the output current while changing the value of the intermediate voltage, and sets the intermediate voltage to a value that determines that the power consumption of the second power source is low. This can be achieved with the device.

  Also, a voltage output setting method for an output voltage variable power supply in which a DC-DC power supply is connected to the load side, the step of measuring a current value at the voltage with at least three voltages within a predetermined voltage range. Determining at least three power consumptions at at least three voltages; selecting a lower power consumption among the at least three power consumptions; and at least one of the at least three powers that have obtained the lower power consumption. And a voltage output setting method for the variable output voltage power supply including the step of setting the voltage output.

  It is possible to realize a power-saving power supply device, an information processing device, and a voltage output setting method for a variable output voltage power supply.

Hereinafter, embodiments of the present invention will be described using examples with reference to the drawings.
First, the operation principle of this embodiment will be briefly described with reference to FIGS. Here, FIG. 3 is a diagram for explaining the relationship between the input voltage and the conversion efficiency when the output current of the DC-DC power supply is constant. FIG. 4 is a diagram for explaining the relationship between the input voltage and the input power when the output current of the DC-DC power supply is constant. Here, FIG. 3 and FIG. 4 are derived from FIG. That is, FIG. 3 is when Io = Ioc in FIG. Further, FIG. 4 is derived from FIG. 3 and shows the lowest input power at the input voltage with the highest conversion efficiency. Since FIG. 3 and FIG. 4 are based on FIG. 2, there is a bottom in FIG. However, more generally, it shows a tendency of monotonic increase, monotonous decrease, bottom, or peak. As a result, if it is monotonously increased, the energy consumption is minimized when the minimum voltage of the DC-DC power supply specification is used. On the other hand, if it is monotonously decreasing, it will be the most energy efficient if the maximum voltage of the DC-DC power supply specification is used. Similarly, the input voltage that gives the bottom is used for the bottom, and the minimum or maximum voltage of the DC-DC power supply specification is used for the peak.

  Next, the configuration of a communication apparatus that is an example of an information processing apparatus will be described with reference to FIG. Here, FIG. 5 is a block diagram of the communication apparatus. In FIG. 5, the communication device 1 includes an AC-DC power supply 2, a plurality of logic modules 30, and a control module 40.

  The AC-DC power supply 2 generates an intermediate voltage Vm in the apparatus from the AC input. The AC-DC power supply 2 includes an output voltage adjustment unit 21 and an output current measurement unit 22 therein. The AC-DC power supply 2 receives the voltage control signal 51 and transmits the current measurement value signal 52 to and from the control module 40.

  The logic module 30 operates using the intermediate voltage Vm as a power source, and includes a logic circuit and a DC-DC power source for generating a power source used in the logic circuit. Here, a DC-DC power supply and a logic circuit mounted on a plurality of logic modules 30 are combined and shown as a DC-DC power supply 100 and a logic circuit 110 on behalf of the logic module 30-1. Here, the DC-DC power supply 100 has input DCVm volts, Im amps, output DCVo volts, Io amps, and conversion efficiency η (Vm, Io). Further, the DC-DC power supply 100 maintains the output Vo in the range of the input VmL to VmH.

  The logic module 30 has an interface with the outside of the apparatus through the communication cable 6, and the current consumption characteristic of the logic module 30 varies depending on the characteristics of data traffic transmitted and received through the communication cable 6. Further, the logic module 30 has an interface of an operation state signal 53 with the control module 40, and the operation state signal 53 is used to transmit / receive a data traffic amount (BPS (Bit Per Second) value) and a transmission / reception packet amount (PPS ( Packet Per Second) value) and the like are transmitted to the control module 40.

  The control module 40 controls the intermediate voltage Vm by the voltage control signal 51 with respect to the AC-DC power supply 2, observes the current value supplied to the logic module 30 by the current value signal 52, and consumes power by the logic module 30. A control operation for minimizing Pi is performed. This control operation can be performed autonomously, or an operation state signal 53 from the logic module 30 can be used as a trigger.

  The control module 40 includes a program execution unit including a microcomputer (not shown), a control signal output, and an observation signal input circuit (not shown). The control module 40 gradually changes the output of the AC-DC power supply 2 in the range of VmL to VmH in which the DC-DC power supply 100 can output a constant voltage, accumulates the product with the measured current value, and stores the power Pi. Find the operating point Vm (kmin) that minimizes. The control module 40 adjusts the output voltage adjustment unit 21 of the AC-DC power supply 2 and optimizes the power consumption efficiency of the logic module 30 by setting the output to Vm (kmin).

  The current consumption characteristics of the logic module will be described with reference to FIG. FIG. 6 is a block diagram of the communication apparatus, and shows the configuration of the logic module of FIG. 1 in detail. In FIG. 6, the communication device 1 includes an AC-DC power supply 2 and a logic module 30. Further, the logic module 30 includes a plurality of DCDC power supplies and a plurality of logic circuits. The plurality of DC-DC power supplies output DC voltages of DC5V, DC3.3V, DC2.5V, and DC1.8V. The plurality of DC-DC power supplies can be regarded as one DC-DC power supply 100. The logic circuit includes a physical layer processing unit 111, a forwarding processing unit 112, a packet processing unit 113, and a control plane unit 114. The physical layer processing unit 111 operates at DC 5 volts, and the forwarding processing unit 112 operates at DC 3.3 volts. The packet processing unit 113 operates at DC 2.5 volts, and the control plane unit 114 operates at DC 1.8 volts.

Generally, the communication processing apparatus is divided into a data plane unit 115 that performs data transfer processing and a control plane unit 114 that controls transfer. The packet processing unit 113, the forwarding processing unit 112, and the physical layer processing unit 111 in FIG. 6 constitute a data plane unit 115.
In FIG. 6, the control module is omitted for convenience of illustration.

  The power consumption characteristics of the processing unit of the logic circuit will be described with reference to FIG. Here, FIG. 7 is a diagram illustrating the power consumption characteristics of the processing unit of the logic circuit. In FIG. 7, the power consumption of each processing unit of the communication device 1 generally changes depending on the data traffic characteristics that change from moment to moment. At that time, the conversion efficiency η of the DC-DC power supply that supplies power to each processing unit also changes. Therefore, the power supply efficiency of the entire logic module also changes from moment to moment. For this reason, if the supply voltage Vm to the logic module is constant, detailed efficiency cannot be achieved.

  An intermediate voltage determination algorithm for obtaining the maximum efficiency will be described with reference to FIGS. 8 and 9. Here, FIG. 8 is a diagram for explaining the relationship between the output voltage (intermediate voltage) of the AC-DC power supply and the output power. FIG. 9 is an operation flowchart of the control module.

  In FIG. 8, the range of the input specifications VmL to VmH of the DC-DC power supply 100 is divided into N (N is an integer of 2 or more) to be Vm (0) to Vm (N). The control module 40 measures Ii (k) at each measurement voltage and calculates electric power Pi (k) = Vm (k) · Ii (k).

  In FIG. 9, the control module 40 sets a parameter k to 0 (zero) (S1). The control module 40 divides the range of the input specifications VmL to VmH of the DC-DC power supply 100 by the division number N (N is a natural number), and calculates a voltage step ΔVm (delta Vm) (S2). The control module 40 sets Vm (0) to Vm (0) (S3). Next, the control module 40 uses the voltage control signal 51 to the output voltage adjustment unit 21 as an intermediate voltage Vm (k) volts. (S4). The output voltage adjustment unit 21 sets the intermediate voltage Vm (k) volts, and the control module 40 grasps the output current Ii (k) measured by the output current measurement unit 22 (S5).

  The control module 40 calculates the power P (k) at that time from Vm (k) · Ii (k) (S6). The control module 40 determines whether or not the parameter k is equal to the division number N (S7). If Yes, k that gives the minimum value from the array of Pi (k) is set to Kmin (S8). Using the voltage control signal 51, the intermediate voltage Vm (kmin) is set to the output voltage adjusting unit 21 (S9), and the process ends.

  In Step 7, if No, the control module 40 increments the parameter k (S10). The control module 40 sets Vm + k · ΔVm to Vm (k) (S11), and returns to Step 4.

  Note that the operation shown in FIG. 9 changes the output voltage of the AC-DC power supply 2 within the range of the input voltage specifications VmL to VmH of the DC-DC power supply 100, so there is no problem in the actual operation of the communication apparatus. Never give. Further, although the voltage variable range VmL to VmH is the input specification of the DC-DC power supply 100, the output voltage variable specification of the AC-DC power supply may be used. That is, as long as the input specification of the DC-DC power supply 100 and the output voltage variable specification of the AC-DC power supply overlap, the voltage may be changed within a predetermined voltage range.

  According to the present embodiment, the control module 40 autonomously performs the detection algorithm of the operating point that maximizes the conversion efficiency at regular intervals, so that it operates optimally with respect to the power consumption characteristics that change every moment. Can do. In addition, when the control module 40 constantly monitors and greatly changes the operation state signal 53 from the logic module 30, an operation point detection algorithm that maximizes the conversion efficiency is executed assuming that the operation state of the logic module 30 has changed. Even in this case, the power consumption efficiency follows the operating state of the apparatus and can always be optimized.

It is a figure explaining a symbol. It is a figure explaining the relationship between output current and conversion efficiency. It is a figure explaining the relationship between an input voltage and conversion efficiency. It is a figure explaining the relationship between an input voltage and input electric power. It is a block diagram of a communication apparatus. It is a block diagram of a communication apparatus. It is a figure explaining the power consumption characteristic of the process part of a logic circuit. It is a figure explaining the relationship between the output voltage (intermediate voltage) of AC-DC power supply, and output electric power. It is an operation | movement flowchart of a control module.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Communication apparatus, 2 ... AC-DC power supply, 6 ... Communication cable, 21 ... Output voltage adjustment part, 22 ... Output current measurement part, 30 ... Logic module, 40 ... Control module, 51 ... Voltage control signal, 52 ... Current Value signal, 53... Operational state signal, 100... DC-DC power supply, 110... Logic circuit, 114.

Claims (9)

In a power supply device that generates a direct current of an intermediate voltage to be supplied to a DC-DC power supply from an alternating current,
A power supply apparatus, wherein an output current is measured while changing the value of the intermediate voltage, and the intermediate voltage is set to a value for determining that the power consumption of the DC-DC power supply is low. In an information processing apparatus including a first power source that generates a direct current of an intermediate voltage from alternating current, and a second power source that generates a direct current of an electronic component supply voltage from the intermediate voltage,
The information processing apparatus according to claim 1, wherein the first power source includes an output voltage adjustment unit that adjusts the intermediate voltage, and an output current measurement unit that measures a current value of the intermediate voltage. A first power source that generates a direct current of an intermediate voltage from an alternating current; a second power source that generates a direct current of an electronic component supply voltage from the intermediate voltage; and the intermediate voltage of the first power supply is set, and the intermediate voltage And an information processing apparatus including a control unit that monitors the current value of
The control unit monitors the output current while changing the value of the intermediate voltage, and sets the intermediate voltage to a value that determines that the power consumption of the second power supply is low. . The information processing apparatus according to claim 2 or 3,
The information processing apparatus, wherein the second power source is mounted on a logic module on which a logic circuit is mounted. The information processing apparatus according to claim 3,
The information processing apparatus, wherein the control unit periodically sets the intermediate voltage. The information processing apparatus according to claim 4,
The information processing apparatus, wherein the control unit sets the intermediate voltage based on a signal from the logic module. A voltage output setting method for an output voltage variable power supply in which a DC-DC power supply is connected to the load side,
Measuring a current value at the voltage with at least three voltages within a voltage range of a predetermined range;
Determining at least three power consumptions at the at least three voltages;
Selecting less power consumption from the at least three power consumptions;
A voltage output setting method for an output voltage variable power supply, including the step of setting one of the at least three powers that have obtained less power consumption as the voltage output. A voltage output setting method for an output voltage variable power supply according to claim 7,
The step of measuring the current value is started periodically, and a voltage output setting method for an output voltage variable power supply. A voltage output setting method for an output voltage variable power supply according to claim 7,
The step of measuring the current value is started based on a signal from a load of the DC-DC power supply, and a voltage output setting method for an output voltage variable power supply.

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