JP2020067760A - Computer system and computer system power supply method - Google Patents

Abstract

To appropriately prevent voltage drop in starting with a simple configuration in a system including a plurality of computers.SOLUTION: A computer system comprises: a power supply device 90 for outputting DC power; and N computers 100 to 400 (N is an integer of 2 or more) driven by the DC power that is supplied via power cables. The DC power is output from the power supply device 90. The power cables are power supply cables 81 to 84 and a device connection cable 85. The power supply cables 81 to 84 connect the power supply device 90 to the computers 100 to 400 to supply the DC power from the power supply device 90 to each of the computers 100 to 400. The device connection cable 85 connects between the N computers 100 to 400 so that the DC power can be supplied via another computer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a computer system and a computer system power supply method, and more particularly to a technique for supplying power to a plurality of computers.

  In industrial systems, various systems having a plurality of computers have been put into practical use. For example, in a printing system including a plurality of printing machines (image forming apparatuses), there is a printing system including a plurality of computers that control each printing machine and store and transfer printing data.

FIG. 7 is a diagram showing an example of a power supply configuration of a conventional system including a plurality of computers.
In the example shown in FIG. 7, four computers 10, 20, 30, and 40 perform distributed control and data processing required for the printing system, such as control for printing and storage of print data.

The four computers 10 to 40 are operated by the DC power supply from the power supply device 90.
That is, the power supply device 90 includes a terminal portion 91 that outputs a power source of DC 12V and a terminal portion 92 that is at the ground potential GND, and the terminal portions 91 and 92 and the computers 10 to 40 are connected to the individual power cables 81 and Connect at 82, 83, 84.
For example, the power supply input terminal 11 of the first computer 10 is connected to the DC 12V terminal portion 91 of the power supply device 90 using one line 81a of the power supply cable 81. Further, the ground terminal 12 of the first computer 10 is connected to the terminal portion 92 of the ground potential GND of the power supply device 90 using the other line 81b of the power cable 82.

Similarly, the power input terminal 21 and the ground terminal 22 of the second computer 20 are connected to the terminal portions 91 and 92 of the power supply device 90 by using the lines 82a and 82b of the power cable 82. The power input terminal 31 and the ground terminal 32 of the third computer 30 are connected to the terminal portions 91 and 92 of the power supply device 90 using the lines 83a and 83b of the power cable 83. Further, the power input terminal 41 and the ground terminal 42 of the fourth computer 40 are connected to the terminal portions 91 and 92 of the power supply device 90 by using the lines 84a and 84b of the power cable 84.
By connecting in this manner, the DC 12V power from the power supply device 90 is supplied to the computers 10 to 40, and the computers 10 to 40 are operated by the DC 12V power.

By the way, normally, a computer requires a larger current when it is started than when it is stationary. For example, in the case of a configuration in which a DC 12 V power source is supplied as in the configuration shown in FIG. 7, a current of several hundred mA to 1 A may be sufficient in the steady state, but a large current of several times that in the steady state, which is several A, may be generated at startup. You will need it.
As described above, when a large current flows at the time of startup, the power supply voltage of the power supply device 90 cannot maintain the specified value of 12 V due to the resistance of the cable. If the power supply voltage at start-up cannot maintain the specified value, the computer may not start properly. Generally, the power supply voltage of a computer is required to suppress fluctuation from a specified value such as 12 V to 5% or less, and depending on conditions such as cable length, a voltage drop of more than 5% may occur. is there.

  In Patent Document 1, a power supply cable for supplying a DC power supply from a power supply device (power supply unit) to a plurality of computers (servers) is limited to a predetermined length, and the voltage of the power supply supplied to the computers is reduced. The technology to prevent this is described.

JP, 2011-2229281, A

As described in Patent Document 1, by limiting the length of the power cable, the voltage drop of the power supplied to the computer can be suppressed to some extent. However, if the length of the power supply cable is limited, the installation position when installing a plurality of computers is restricted to the vicinity of the power supply device, so that there is a problem that the computers cannot be freely installed. In addition, there is a limit to the effect of suppressing the voltage drop that can be realized by limiting the length of the power cable, and there is a problem that it cannot be said that the voltage drop at the time of startup is sufficiently prevented.
Further, as another method for preventing the voltage drop at the time of starting, it is known to use a thick power cable that can withstand a large current at the time of starting. However, a thick power cable that can withstand a large current at startup is more expensive than a normal power cable, and there is a problem that the cost required to build a system increases.

  An object of the present invention is to appropriately prevent a voltage drop at startup with a simple configuration in a system including a plurality of computers.

The computer system of the present invention includes a power supply device that outputs a DC power supply, and N DC power supplies output from the power supply device via a power cable and driven by the supplied DC power supply (N is 2 or more). (Integer) computer.
The computer system of the present invention has a power supply cable and an inter-device connection cable as a power cable, and connects the power supply device and a plurality of computers with the power supply cable, and respectively connects the power supply device to the computer. In addition to supplying DC power to the computer, the N computers are connected by a cable for connecting devices, and DC power is supplied via another computer.

The computer system power supply method of the present invention is a power supply method for supplying DC power from a power supply device to a computer system equipped with N (N is an integer of 2 or more) computers driven by a DC power supply. is there.
In the computer system power supply method, a power supply process of directly supplying DC power from a power supply device to the N computers by using a power supply cable, and connecting the N computers to each other between devices. Power distribution processing that distributes DC power using cables is performed.

  According to the present invention, since a plurality of (N) computers are connected using a cable for connecting devices, it becomes possible to distribute DC power from the power supply device via each computer. You can start the computer with a large current while preventing the voltage drop.

It is a block diagram which shows the example of a system by the example of one Embodiment of this invention. It is a flow chart which shows the example of the starting processing by the example of one embodiment of the present invention. It is a characteristic view which shows the example of a change of the power supply voltage by one embodiment of this invention. It is a characteristic view which shows the example of a change of the power supply voltage when this invention is not applied. It is explanatory drawing which shows the example of the electric current of each cable at the time of starting by one Embodiment of this invention. It is a block diagram which shows the example of a system by the other example of embodiment of this invention. It is a block diagram which shows an example of the conventional system.

Hereinafter, an embodiment of the present invention (hereinafter referred to as “this example”) will be described with reference to FIGS. 1 to 6.
[System configuration]
FIG. 1 shows the computer system configuration of this example.
The computer system of this example includes four computers 100, 200, 300, 400. Then, the four computers 100 to 400 perform control and data processing necessary for the printing system in a distributed manner, such as control for printing and storage of print data.

The four computers 100 to 400 are operated by the DC power supply from the power supply device 90.
That is, the power supply device 90 includes a terminal portion 91 that outputs a DC 12V power source and a terminal portion 92 that has the ground potential GND. The terminal portions 91 and 92 are connected to the DC power supply circuit 93, and a DC 12V power source is output from the DC power supply circuit 93 via the terminal portions 91 and 92, and power supply processing to each of the computers 100 to 400 is performed. .
The terminal portions 91 and 92 of the power supply device 90 and the computers 100 to 400 are connected by individual power supply cables 81, 82, 83 and 84.

  For example, the power input terminal 110 of the first computer 100 is connected to the DC 12V terminal portion 91 of the power supply device 90 using one line 81 a of the power cable 81. In addition, the ground terminal 120 of the first computer 100 is connected to the terminal portion 92 of the ground potential GND of the power supply device 90 using the other line 81b of the power cable 82.

  Similarly, the power supply input terminal 210 and the ground terminal 220 of the second computer 300 are connected to the terminal portions 91 and 92 of the power supply device 90 using the lines 82a and 82b of the power supply cable 82. The power input terminal 31 and the ground terminal 32 of the third computer 300 are connected to the terminal portions 91 and 92 of the power supply device 90 using the lines 83a and 83b of the power cable 83. Further, the power input terminal 410 and the ground terminal 420 of the fourth computer 400 are connected to the terminal portions 91 and 92 of the power supply device 90 by using the lines 84a and 84b of the power cable 84.

Up to this point, the configuration is the same as the conventional system configuration described in FIG. 7, but in the case of the computer system of this example, the power input terminals 110, 210, 310, 410 of the four computers 100 to 400 and the ground. The terminals 120, 220, 320 and 420 are connected to each other by a power cable 85.
That is, the power input terminals 110, 210, 310, 410 of the computers 100 to 400 are connected to each other through one line 85 a of the power cable 85. Further, the ground terminals 120, 220, 320, 420 of each of the computers 100-400 are connected to each other via the other line 85b of the power cable 85.

As described above, in the computer system of this example, the power cable 85 is connected to the power input terminals 110, 210, 310 and 410 in addition to the power cables 81 to 84. Therefore, each of the power input terminals 110, 210, 310, 410 and the ground terminals 120, 220, 320, 420 of the computers 100 to 400 has a terminal shape capable of connecting two lines.
The power cables 81 to 84 that connect the power supply device 90 to the four computers 100 to 400 are set to be relatively long. For example, the power cables 81 to 84 are set to have a maximum length of about 5 m so that the four computers 100 to 400 can be installed with some distance therebetween.

  In the following description, when it is necessary to distinguish the power cables 81, 82, 83, 84 and the power cable 85, the power cables 81, 82, 83, 84 are referred to as power supply cables, and the power cable 85 is referred to as the power supply cable 85. It is called a cable for connecting devices.

  The power input terminal 110 and the ground terminal 120 of the first computer 100 are connected to the power input section 101, and the DC 12V power obtained at the power input terminal 110 is supplied to the power input section 101. The power supply input unit 101 converts the input DC 12V power supply into a power supply of a voltage that operates each unit in the first computer 100. Then, the power input unit 101 supplies the obtained power to each unit (the processing unit 102, the interface 103, etc., which will be described later) in the first computer 100.

  Similarly, the power supply input terminals 210, 310, 410 and the ground terminals 220, 320, 420 of the second, third and fourth computers 200, 300, 400 are connected to the power supply input sections 201, 301, 401 to input power. The units 201, 301, and 401 are converted into a power supply of a voltage for operating each unit in each of the computers 200, 300, and 400.

The first computer 100 includes a processing unit 102 that performs arithmetic processing and data storage processing, and an interface 103 that communicates with the outside. Similarly, the second, third and fourth computers 200, 300, 400 also include processing units 202, 302, 402 and interfaces 203, 303, 403.
The interfaces 103, 203, 303, and 403 of the computers 100, 200, 300, and 400 are connected to the network 70, and data transfer between the computers 100 to 400 is performed via the network 70.

  Note that each computer 100 to 400 stands by in a standby state in which it performs minimum processing such as communication with other devices when it is not activated, and shifts to the activated state to perform arithmetic processing, data storage processing, etc. become. In each of the computers 100 to 400, the current consumption temporarily increases to several times (for example, about 5 times) that during the start-up in the steady state during the start-up processing in which the standby state is switched to the start-up state.

Here, in the computer system of the present example, the individual power supply cables 81 to 84 for supplying power to the respective computers 100 to 400 have a current of at least a steady state current plus a certain amount of current. A power cable with a permissible current that can withstand is used. However, the current obtained by adding a certain amount of current to the current in the steady state may be a value smaller than the current value that flows when one computer is started.
Specifically, in the computer system of this example, a power cable that can withstand a current about three times the current in a steady state is used. As the inter-device connection cable 85, a power supply cable having an allowable current equivalent to that of the power supply cables 81 to 84 is used.

[Startup processing]
FIG. 2 is a flowchart showing a processing example when starting each of the computers 100 to 400 in the computer system of this example.
The activation of the entire computer system of this example is performed by inputting an activation instruction from the outside to the first computer 100, for example. The flowchart of FIG. 2 shows an example in which the first computer 100 activates each computer 100 to 400 in the system.

First, the first computer 100 determines whether or not there is an input from the outside that gives a system startup instruction (step S11). When the boot instruction is not input (No in step S11), the first computer 100 waits until the boot instruction is input.
Then, when the activation instruction is input (Yes in step S11), the first computer 100 starts the process of activating the first computer 100 itself (step S12). After that, the first computer 100 waits for a fixed time (for example, about 500 msec) (step S13), and then sends an activation instruction to the second computer 200 (step S14).

  Furthermore, the first computer 100 waits for a fixed time (the same time as step S13) (step S15), and then sends a boot instruction to the third computer 300 (step S16). Furthermore, the first computer 100 waits for a fixed time (the same time as step S13) (step S17), then sends a boot instruction to the fourth computer 400 (step S18), and finishes the boot process.

  FIG. 3 shows changes in the power supply voltage of four computers 100 to 400 included in the computer system of this example at the time of startup. 3A, 3B, 3C, and 3D are supplied to the power input units 101 to 401 of the first computer 100, the second computer 200, the third computer 300, and the fourth computer 400, respectively. The change in the voltage of the power supply is shown. The horizontal axis of FIG. 3 is time, and the broken line shown in each voltage waveform shows the level at which the voltage has dropped by 5% from the specified value (here, 12 V).

  In FIG. 3, times t1, t2, t3, and t4 indicate timings at which the first computer 100, the second computer 200, the third computer 300, and the fourth computer 400 start the boot process, respectively. By performing the activation control process as shown in the flowchart of FIG. 2, the timings t1, t2, t3, and t4 at which the computers 100 to 400 are activated are set to be different by about 500 msec for each computer.

  Here, in the computer system of the present example, the device-to-device connection cable 85 is provided and connected so that the power can be distributed among the computers 100 to 400, so that a large current flows when the computers 100 to 400 are activated. Also, the voltage drop of the power supply can be suppressed to 5% or less. However, in the case of the computer system of this example, one of the computers is connected because the inter-device connection cable 85 is provided and the power input terminals 110 to 410 and the ground terminals 120 to 420 of the computers 100 to 400 are connected. At the time of startup, the voltage drop of 5% or less similarly occurs for the other remaining computers.

Here, for comparison, in the computer system of the present example, in the case where the inter-device connection cable 85 is not provided (that is, the connection configuration similar to that in FIG. 7), the start timing shown in FIG. 2 is shifted. FIG. 4 shows the fluctuation of the power supply voltage of the four computers.
4A, 4 </ b> B, 4 </ b> C, and 4 </ b> D show variations in the power supply voltage of the four computers 100 to 400, respectively, as in the example of FIG. 3.

For example, when the first computer 100 starts up at the timing t1, a large current flows, and the power supply voltage of the first computer 100 drops significantly beyond 5%. Similarly, when the second computer 200, the third computer 300, and the fourth computer 400 are activated at timings t2, t3, and t4, the power supply voltage of each of the computers 200, 300, and 400 is greatly reduced to more than 5%. .
However, in the case of the example of FIG. 4, the voltage drop is only in the activated computer, and the voltage drop does not spread to other computers.

FIG. 5 shows, in the computer system of this example, the currents flowing through the cables 81 to 85 when the first computer 100 is activated.
In FIG. 5, the current i indicates the value of the current flowing through each of the computers 100 to 400 in the steady state. Further, when one computer (for example, the computer 100) starts up, a current 5i that is about 5 times that in a steady state flows.

Here, in the computer system of this example, by providing the inter-device connection cable 85, the power supply flows from the power supply device 90 to the four computers 100 to 400 are equalized. Then, the current 2i flows through any of the power supply cables 81 to 84. Then, from each of the three computers 200 to 400 other than the activated first computer 100, the current i is distributed to the first computer 100 via the inter-device connection cable 85, and the total current 3i is the inter-device connection. It flows to the first computer 100 via the cable for use 85.
Therefore, a current 5i obtained by adding the current 2i obtained via the power supply cable 81 and the current 3i flowing through the inter-device connection cable 85 is obtained to the first computer 100 which is in operation.
In the example of FIG. 5, it is assumed that the current i is flowing in the steady state as the three computers 200 to 400 other than the first computer 100, but when the computers 200 to 400 are in the standby state. The current flowing through these computers 200 to 400 has a value smaller than the current i.

  As described above, according to the computer system of the present example, by connecting the computers 100 to 400 with the inter-device connection cable 85 so that the power can be distributed, even when a large current is required at startup, Large current does not concentrate on one cable. Therefore, a large voltage drop (a voltage drop exceeding 5% as shown in FIG. 4) at the time of starting each of the computers 100 to 400 does not occur, and the starting process of each of the computers 100 to 400 can be properly executed. .

  In addition, since a large current does not flow concentrated on one cable at the time of startup, the power supply cables 81 to 84 can be made relatively long. Specifically, the power supply cables 81 to 84 for supplying a DC 12V power supply can be long-distance cables of about 5 m, so that the four computers 100 to 400 have only that degree of freedom in installation. improves.

[Modification]
In the configuration shown in FIG. 1, the inter-device connection cable 85 is a power cable that connects the four computers 100 to 400 to each other. Alternatively, two computers may be connected in sequence. That is, as shown in FIG. 6, three inter-device connecting cables 86, 87, 88 are prepared. Then, the power input terminal 110 of the first computer 100 and the power input terminal 210 of the second computer 200 are connected by one line 86a of the cable 86 for connecting the devices. Further, the ground terminal 120 of the first computer 100 and the ground terminal 220 of the second computer 200 are connected by the other line 86b of the inter-device connection cable 86.

Further, the power input terminal 210 of the second computer 200 and the power input terminal 310 of the third computer 300 are connected to each other via one line 87a of the cable 87 for connecting between devices. In addition, the ground line 220 of the second computer 200 and the ground line 320 of the third computer 300 are connected by the other line 87b of the cable 87 for connecting between devices.
Further, the power input terminal 310 of the third computer 300 and the power input terminal 410 of the fourth computer 400 are connected by one line 88a of the cable 88 for connecting devices. Further, the ground terminal 320 of the third computer 300 and the ground terminal 420 of the fourth computer 400 are connected by the other line 88b of the inter-device connection cable 88.
In the case of the example shown in FIG. 6, at least the power input terminals 210 and 310 and the ground terminals 220 and 320 of the second computer 200 and the third computer 300 need to have terminal shapes capable of connecting three lines. There is.

  As shown in FIG. 6, even when two devices are sequentially connected with the inter-device connecting cables 86, 87, 88, the current is distributed under the same conditions as the system of the example of FIG. It is possible to prevent excessive voltage drop.

  Further, in the above-described embodiment, the system is provided with four computers, but the present invention is also applicable to a system with a plurality of computers other than four computers. That is, the present invention can be applied to a system that includes N computers (N is an integer of 2 or more) and supplies DC power from one power supply device to the N computers.

  Further, in the above-described embodiment, the start timing is sequentially shifted in all the computers in the system. However, when the voltage drop is within the specified range even if two or more machines are simultaneously started, A plurality of units may be simultaneously activated. Specifically, in a system including N computers, the number of M units (M is less than N and 2 or more when N is less than N is within a range in which the voltage reduction rate of the DC power supply supplied to the computers at startup does not exceed a prescribed reduction rate. It is also possible to simultaneously activate all the computers) and shift the activation timing at the time of activation in units of M computers.

  Further, in the example shown in FIG. 2, although one computer in the system is made to start another computer in order in response to an instruction, another method is used as a process for shifting the start timing of each computer in the system. May be applied. For example, an activation instruction may be sequentially delivered to the four computers 100 to 400 from an external control device other than the four computers 100 to 400 shown in FIG. Alternatively, each computer 100 to 400 may be activated after waiting for a different period after the activation instruction arrives.

  Further, in the above-described embodiment, the example is applied to the computer system including a plurality of computers for the printing system. On the other hand, the present invention may be applied to computer systems for other various industries.

  70 ... Network, 81, 82, 83, 84 ... Power supply cable (power supply cable), 85, 86, 87, 88 ... Power supply cable (device connection cable), 90 ... Power supply device, 91, 92 ... Terminal, 100 ... First computer, 110 ... Power input terminal, 120 ... Ground terminal, 200 ... Second computer, 210 ... Power input terminal, 220 ... Ground terminal, 300 ... Third computer, 310 ... Power input terminal, 320 ... Ground terminal , 400 ... Fourth computer, 410 ... Power input terminal, 420 ... Ground terminal

Claims (5)

A power supply device that outputs a DC power supply, and N (N is an integer of 2 or more) computers that are supplied with DC power output from the power supply device through a power cable and that are driven by the supplied DC power supply. A computer system comprising:
As the power cable, having a power supply cable and a device-to-device connection cable,
The power supply cable is used to connect the power supply device to a plurality of computers so that DC power is supplied from the power supply device to each computer, and the inter-device connection cable is used to connect N computers. A computer system in which DC power is supplied via another computer by connecting the two. The computer system according to claim 1, wherein the N computers are configured to shift a startup timing at startup. The computer system according to claim 2, wherein the N computers communicate with each other so that the respective computers are activated at a shifted timing. Within a range in which the voltage reduction rate of the DC power supply supplied to the computer at the time of startup does not exceed the prescribed rate of decrease, M (M is an integer less than N and 2 or more) computers are simultaneously activated to generate M computers. The computer system according to claim 2, wherein the activation timing at the time of activation is shifted in units of the computer. In a computer system power supply method for supplying DC power from a power supply device to a computer system equipped with N (N is an integer of 2 or more) computers driven by a DC power supply,
A power supply process for directly supplying DC power from the power supply device to the N computers by using a power supply cable;
A computer system power supply method for performing a power distribution process for distributing DC power between N computers by using a cable for connecting devices.

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