Control device

Abstract

A control device according to the present invention includes a state acquisition unit and a calculation unit. The state acquisition unit acquires external factor information indicating a state of one or more types of external factors affecting temperature in a device to be air-cooled. The calculation unit calculates a control value corresponding to the external factor information acquired by the state acquisition unit, by using a model indicating correspondence between the state of the external factors and a control value used to control an air cooling device for air-cooling the device, and instructs the air cooling device to perform air-cooling using the calculated control value.

Description

Control device

[0001] The present invention relates to a control device.

[0002] A communication device is equipped with a fan for air cooling. In a conventional technique, the fan's rotation speed is dynamically controlled based on temperature information of the communication device itself and its mounted components (see, for example, Patent Document 1). FIG. 13 is a functional block diagram showing an example configuration of a communication device of the conventional technique. The communication device has a communication unit for performing communication and a configuration for air cooling the communication device. A temperature acquisition unit acquires temperature information of the communication device and its components. A memory unit stores the relationship between the temperature information and the fan rotation speed. A control unit refers to the memory unit to determine the optimal fan rotation speed for the temperature information acquired by the acquisition unit and instructs the fan unit to operate at the determined fan rotation speed. The fan unit rotates the fan in accordance with the instruction from the control unit to air cool the communication device.

[0003] Patent No. 5177896

[0004] The temperature of a device component is determined by the heat balance for that component. For example, when an external factor, such as a change in ambient temperature or an influx of traffic, occurs that affects the heat balance, the heat flow to the component immediately changes in response to the external factor. Meanwhile, the component's temperature gradually rises or falls, converging to the appropriate temperature based on the heat balance. Thus, there is a time lag between the heat flow and the change in temperature. Conventional technology controls the fan speed based on temperature information, so the fan speed changes to track the temperature. However, due to the time lag between changes in heat flow and temperature, it takes time for the fan speed to reach a necessary and sufficient level when an external factor occurs. Therefore, the target temperature must include a margin to account for changes in the upper limit temperature specified. For these reasons, conventional technology was unable to fully reduce the fan speed during normal operation, which sometimes resulted in insufficient power consumption reduction.

[0005] In view of the above circumstances, an object of the present invention is to provide a control device that can control air cooling of a device so as to further reduce power consumption.

[0006] A control device of one embodiment of the present invention includes a status acquisition unit that acquires external factor information indicating the state of one or more external factors that affect the temperature within the device to be air-cooled, and a calculation unit that uses a model that indicates the correspondence between the state of the external factors and the control values ​​used to control the air-cooling device that air-cools the device, calculates a control value corresponding to the external factor information acquired by the status acquisition unit, and instructs the air-cooling device to perform air-cooling using the calculated control value.

[0007] The present invention makes it possible to control the air cooling of the device so as to further reduce power consumption.

[0008] FIG. 1 is a functional block diagram of a communication device according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of a model according to an embodiment. FIG. 3 is a functional block diagram of a communication device according to a first embodiment. FIG. 4 is a functional block diagram of a communication device according to a second embodiment. FIG. 5 is a functional block diagram of a communication device according to a third embodiment. FIG. 6 is a functional block diagram of a communication device according to a fourth embodiment. FIG. 7 is a functional block diagram of a communication device according to a fifth embodiment. FIG. 8 is a flow diagram showing processing of a communication device according to the sixth embodiment. FIG. 9 is a functional block diagram of a communication device according to a seventh embodiment. FIG. 10 is a functional block diagram of a communication device according to an eighth embodiment. FIG. 11 is a functional block diagram of a communication device according to the prior art.

[0009] An embodiment of the present invention will be described in detail below with reference to the drawings. In this embodiment, factors that affect the heat balance of components used in an air-cooled device are defined as "external factors." Examples of external factors include the presence or absence of peripheral devices and changes in outside temperature. If the device is a communication device, other external factors include traffic flowing into the communication device. Furthermore, a formula, algorithm, or the like that determines a fan control value according to the state of each external factor is defined as a model. A control device that controls the air-cooling of the communication device stores predefined models. The control device acquires information indicating the state of each external factor and calculates an optimal fan control value using the state of each external factor indicated by the acquired information and the stored model. The control device controls the fan to rotate using the calculated control value, thereby achieving optimal air-cooling according to the state of the external factors at that time. The following description uses a case in which the control value is the fan rotation speed as an example, but any type of control value for controlling the fan rotation speed can be used.

[0010] 1 is a functional block diagram showing an example of the configuration of a communication device 1 according to this embodiment. Only functional blocks related to this embodiment are shown in FIG. 1. The communication device 1 includes a control unit 2, a fan unit 6, and a communication unit 7.

[0011] The control unit 2 is configured using a processor such as a CPU (Central Processing Unit) and a memory (main storage device). The control unit 2 functions when the processor executes a program. Note that all or part of the functions of the control unit 2 may be realized using hardware such as an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array). The program may be recorded on a computer-readable recording medium. Examples of computer-readable recording media include portable media such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, and a semiconductor storage device (e.g., an SSD: Solid State Drive), as well as storage devices such as a hard disk or semiconductor storage device built into a computer system. The program may be transmitted via a telecommunications line.

[0012] The control unit 2 functions as a control device for the fan unit 6. The control unit 2 includes a state acquisition unit 3, a model storage unit 4, and a rotation speed calculation unit 5.

[0013] The status acquisition unit 3 acquires information indicating the status of external factors that affect the heat balance. Examples of external factors include, but are not limited to, the presence or absence of peripheral devices, changes in outside temperature, and the amount of traffic processed by the communication unit 7. The presence or absence of peripheral devices indicates whether or not other devices are present around the communication device 1. For example, the status acquisition unit 3 may receive information on the presence or absence of peripheral devices from other devices connected to the communication device 1 or read it from a recording medium. The status acquisition unit 3 may also acquire information on the presence or absence of peripheral devices input through an input device (not shown), such as a keyboard. The status acquisition unit 3 may acquire information on changes in outside temperature based on temperature information measured by an external temperature sensor, or based on temperature information or temperature change information received from other devices connected to the communication device 1.

[0014] The model storage unit 4 is configured using a storage device such as a magnetic hard disk drive or a semiconductor storage device. The model storage unit 4 stores a heat balance model that is determined in advance according to the characteristics of the communication device 1. The model represents the correspondence between a combination of the states of one or more external factors and the fan rotation speed.

[0015] The rotation speed calculation unit 5 obtains, as external factor data, information representing the state of the external factor obtained by the state acquisition unit 3. Note that information obtained based on the information representing the state of the external factor obtained by the state acquisition unit 3 may also be used as external factor data. The rotation speed calculation unit 5 calculates the optimal fan rotation speed for the target temperature by substituting the external factor data into the model stored in the model storage unit 4. The rotation speed calculation unit 5 outputs a rotation instruction to the fan unit 6 to rotate the fan at the calculated rotation speed.

[0016] The fan unit 6 is an air-cooling device that cools the communication device 1. The fan unit 6 generates cooling air by rotating the fan based on the rotation instruction received from the rotation speed calculation unit 5, thereby cooling the communication device 1. The communication unit 7 performs communication. The type of communication is arbitrary. For example, the communication unit 7 may perform wireless communication, wired communication, or both.

[0017] Here, a description will be given of an example of calculation of fan rotation by the rotation speed calculation unit 5. The model is expressed by, for example, the following equations (1) and (2).

[0018] F(d)=F(f)-F(t)...(1)

[0019] R=k×F(d)…(2)

[0020] F(d) is the amount of heat dissipated from the device. F(f) is the sum of the heat inflow from the outside and the heat generated within the device. F(t) is the amount of change in the amount of heat held by the device. R is the fan rotation speed. k is a coefficient that derives the required fan rotation speed from F(d).

[0021] Keeping the component temperature constant and maintaining the target temperature, which is the upper limit temperature specified in the specifications of the communication device 1, is equivalent to setting F(t) = 0. In other words, the control unit 2 controls the fan rotation speed so that F(f) - F(d) = 0. This prevents the fan from over-rotating, thereby saving power.

[0022] External factors such as the presence or absence of peripheral devices, changes in outside temperature, and traffic volume are all factors that affect F(f). For example, if the presence or absence of peripheral devices is parameter p1, the change in outside temperature is parameter p2, and the traffic volume is parameter p3, F(f) can be expressed as F(f(p1), f(p2), f(p3)). As described above, F(f) is the sum of the heat inflow from the outside and the heat generated within the device. The presence or absence of peripheral devices and changes in outside temperature are parameters related to the heat inflow from the outside, while the traffic volume is a parameter related to the heat generated within the device. The reason why the traffic volume is related to the heat generated within the device is that components (such as LSIs) within the device generate heat due to traffic processing. Other factors that cause heat generation within the device include all those that generate power in the components within the device, such as data backup from the device and various control processes. However, the degree of impact varies depending on the device and component implementation, so it is desirable to incorporate the factors that have the greatest impact within the device as model parameters.

[0023] The heat generation term in F(f) includes external heat generation and internal heat generation, both of which are difficult to control. On the other hand, as shown in equation (2), the heat dissipation amount F(d) is determined by the fan rotation speed. Therefore, the rotation speed calculation unit 5 controls the fan rotation speed F(d) = k × R according to the value of F(f) so that F(f) - F(d) = F(t) = 0. Specifically, the rotation speed calculation unit 5 calculates F(f) based on the state of each external factor, and, as shown in equation (1), calculates F(d) by subtracting a constant value of F(t) from the calculated F(f). The rotation speed calculation unit 5 then uses the calculated F(d) to calculate the fan rotation speed R according to equation (2). In this way, the heat generation amount is modeled, and the fan rotation speed is calculated so that the heat generation amount = heat dissipation amount is constant.

[0024] The model may also be in tabular form. For example, FIG. 2 is a diagram showing an example of a tabular model. The tables shown in FIGS. 2(a) and 2(b) provide fan rotations per minute (rpm) corresponding to combinations of outside air temperature and the presence or absence of adjacent devices. The rotation speed calculation unit 5 may obtain the fan rotation speed using the table in FIG. 3(a) when the traffic volume is 0 to 1 Gbps (gigabits per second), and may obtain the fan rotation speed using the table in FIG. 3(b) when the traffic volume is 1 to 2 Gbps. Even if the type of external factor used is the same, the characteristics of each external factor, such as the value range and rotation speed, vary depending on the communication device 1 and the fan unit 120.

[0025] According to this embodiment, even when a change occurs in an external factor, the fan rotation speed can be controlled to the optimum value for the heat balance that immediately satisfies the target temperature, so the target temperature can be set to a temperature close to the upper limit of the specifications. Therefore, it is possible to reduce power consumption during normal operation more than with conventional technology. In addition, because this is a technology that reduces the fan rotation speed, it is also possible to extend the life of the fan grease. Each embodiment will be described below.

[0026] 3 is a functional block diagram showing an example of the configuration of a communication device 100 according to a first embodiment. The communication device 100 includes a control unit 110, a fan unit 120, and a communication unit 7.

[0027] The control unit 110 includes a status acquisition unit 111, a model storage unit 112, and a rotation speed calculation unit 113. The control unit 110, the status acquisition unit 111, the model storage unit 112, and the rotation speed calculation unit 113 correspond to the control unit 2, the status acquisition unit 3, the model storage unit 4, and the rotation speed calculation unit 5 of the communication device 1 shown in FIG. 1 , respectively. The status acquisition unit 111 acquires the status of external factors that affect the heat balance. The targets and types of external factors whose status are acquired may be any number depending on one or more device characteristics. The timing at which the status acquisition unit 111 acquires the status may be either a periodic operation or an event operation.

[0028] The model storage unit 112 stores a heat balance model according to the characteristics of the communication device 100. The heat balance model is determined in advance. The predefined model may be in the form of a mathematical formula or a table.

[0029] The rotation speed calculation unit 113 calculates an optimal fan rotation speed for a target temperature by substituting the external factor data obtained by the state acquisition unit 111 into a model stored in the model storage unit 112. For example, the rotation speed calculation unit 113 calculates the fan rotation speed by substituting the external factor data obtained by the state acquisition unit 111 as input parameter values ​​into a mathematical formula for the model. Alternatively, if the model is in a table format, the model storage unit 112 stores a matrix indicating fan rotation speeds corresponding to combinations of ranges of values ​​of the external factor data. The rotation speed calculation unit 113 reads out, from the matrix, the fan rotation speed corresponding to the combination of values ​​of the external factor data obtained by the state acquisition unit 111. The rotation speed calculation unit 113 outputs, to the fan unit 120, a rotation instruction to rotate the fan at the calculated rotation speed or a stop instruction to stop the fan.

[0030] 1 . The fan unit 120 cools the communication device 100 by rotating the fan at a rotation speed according to the rotation instruction received from the rotation speed calculation unit 113. Alternatively, the fan unit 120 stops the rotation of the fan according to the stop instruction received from the rotation speed calculation unit 113.

[0031] According to the control unit 110 of the first embodiment, when an external factor occurs, the fan rotation speed can be controlled to be optimal for the heat balance that immediately satisfies the target temperature, and the target temperature can be set to a temperature close to the upper limit of the specifications of the communication device 100. Therefore, it is possible to reduce power consumption during normal operation more than with conventional techniques.

[0032] Second Embodiment In a second embodiment, a control unit controls a fan of a housing that houses one or more communication devices. The second embodiment will be described, focusing on the differences from the first embodiment.

[0033] Fig. 4 is a functional block diagram showing the configuration of a device housing 200 according to the second embodiment. In the device housing 200 shown in Fig. 4, the same components as those of the communication device 100 of the first embodiment shown in Fig. 3 are given the same reference numerals, and their description will be omitted. The device housing 200 has N communication devices 210 (N is an integer of 1 or more), a control unit 220, and a fan unit 120.

[0034] The communication device 210 has a status acquisition unit 111 and a communication unit 7. The nth communication device 210 (n is an integer between 1 and N) is referred to as communication device 210-n, and the status acquisition unit 111 included in communication device 210-n is referred to as status acquisition unit 111-n. The status acquisition units 111-1 to 111-N perform the same processing as the status acquisition unit 111 of the first embodiment. That is, the status acquisition unit 111-n acquires information on the status of external factors that affect the heat balance of communication device 210-n, and outputs external factor data indicating the acquired information.

[0035] The control unit 220 controls each communication device 210 and the fan unit 120 in the device housing 200. The control unit 220 includes a model storage unit 221 and a rotation speed calculation unit 222. The model storage unit 221 and the rotation speed calculation unit 222 correspond to the model storage unit 4 and the rotation speed calculation unit 5 of the communication device 1 shown in FIG. 1, respectively. The model storage unit 221 stores a heat balance model similar to that of the first embodiment for each communication device 210. When the rotation speed calculation unit 222 receives external factor data from the status acquisition unit 111-n, it selects a model related to the communication device 210-n from the models stored in the model storage unit 221. The rotation speed calculation unit 222 calculates the heat balance using the received external factor data and the selected model, similar to the rotation speed calculation unit 113 of the first embodiment, and obtains the fan rotation speed as a result. Rotation speed calculation unit 222 compares the calculation results of the fan rotation speed required for each of communication devices 210-1 to 210-N and adopts the largest value. Rotation speed calculation unit 222 outputs a rotation instruction to fan unit 120 to instruct the fan to rotate at the adopted fan rotation speed. Fan unit 120 rotates the fan at the rotation speed in accordance with the rotation instruction received from rotation speed calculation unit 222.

[0036] For example, even if the amount of heat generated by communication device 210-1 is the same, the heat generated by other communication devices 210-2 and 210-3 may be large or small. When the heat generated by other communication devices is small, the amount of heat flowing into communication device 210-1 from the surroundings is also small. Therefore, the calculation result of the fan rotation speed is "rotation speed when the heat generated by other communication devices is large > rotation speed when the heat generated by the communication device is small." Therefore, even if the largest value of the fan rotation speed is used, the fan rotation speed will also take into account the heat generated by the other communication devices 210.

[0037] According to the second embodiment, even when there are multiple communication devices in the housing, it is possible to calculate the optimum number of revolutions of the fan and control the rotation.

[0038] Third Embodiment A communication device or a device housing of a third embodiment has a plurality of fans. The third embodiment will be described, focusing on the differences from the first and second embodiments.

[0039] Figure 5 is a functional block diagram showing the configuration of a communication device 300 according to the third embodiment. In Figure 5, parts that are the same as those in the communication device 100 of the first embodiment shown in Figure 3 are given the same reference numerals, and their description will be omitted. The communication device 300 has a control unit 310, M fan units 120, and a communication unit 7. The M fan units 120 will be referred to as fan units 120-1 to 120-M.

[0040] The control unit 310 includes a state acquisition unit 111, a model storage unit 311, and a rotation speed calculation unit 312. The control unit 310, the state acquisition unit 111, the model storage unit 311, and the rotation speed calculation unit 312 correspond to the control unit 2, the state acquisition unit 3, the model storage unit 4, and the rotation speed calculation unit 5 of the communication device 1 shown in FIG. 1, respectively. The model storage unit 311 stores the same models as those in the first embodiment for each of the fan units 120-1 to 120-M. The model for the fan unit 120-m (m is an integer between 1 and M) is referred to as model (m).

[0041] The rotation speed calculation unit 312 reads out each model (m) for m = 1 to M from the model storage unit 311, calculates the heat balance using each model (m) and the external factor data obtained from the status acquisition unit 111, and obtains the fan rotation speed as a result. The rotation speed calculation unit 312 compares the calculation results of the fan rotation speeds calculated using each of models (1) to (M) and adopts the largest value. The rotation speed calculation unit 312 outputs a rotation instruction to each of the fan units 120-1 to 120-M to instruct them to rotate at the adopted fan rotation speed. The fan units 120-1 to 120-M independently rotate their fans at the rotation speeds in accordance with the rotation instructions received from the rotation speed calculation unit 312.

[0042] Fig. 6 is a functional block diagram showing the configuration of a device housing 350 according to the third embodiment. In Fig. 6, the same components as those in the device housing 200 according to the second embodiment shown in Fig. 4 and the communication device 300 according to the third embodiment shown in Fig. 5 are designated by the same reference numerals, and their description will be omitted. The device housing 350 includes communication devices 210-1 to 210-N, a control unit 360, and fan units 120-1 to 120-M.

[0043] The control unit 360 includes a model storage unit 361 and a rotation speed calculation unit 362. The model storage unit 361 and the rotation speed calculation unit 362 correspond to the model storage unit 4 and the rotation speed calculation unit 5 of the communication device 1 shown in FIG. 1, respectively. The model storage unit 361 stores a heat balance model similar to that of the first and second embodiments for each of the fan units 120-1 to 120-M for each communication device 210. A model for the fan unit 120-m (m is an integer between 1 and M) of a communication device 210-n is designated as model (n, m). Note that if a certain fan unit 120-m does not affect the cooling of a certain communication device 210-n, the model storage unit 361 does not need to store the model (n, m).

[0044] The rotation speed calculation unit 362 reads out the model (n, m) of each communication device 210-n, where m = 1 to M, from the model storage unit 361, and calculates the heat balance using the external factor data obtained by the status acquisition unit 111-n and each model (n, m), obtaining the fan rotation speed as a result. The rotation speed calculation unit 362 compares the calculation results of the fan rotation speeds calculated using each of the models (1, 1) to (N, M) and adopts the largest value. The rotation speed calculation unit 362 outputs a rotation instruction to each of the fan units 120-1 to 120-M, instructing them to rotate their fans at the adopted fan rotation speed. The fan units 120-1 to 120-M independently rotate their fans at the rotation speeds in accordance with the rotation instructions received from the rotation speed calculation unit 362.

[0045] In particular, when there are multiple communication devices, the heat balance state of each communication device is often different. According to the third embodiment, by providing multiple fan units, it is possible to appropriately cool each communication device. Therefore, it is possible to reduce power consumption more than in the first and second embodiments.

[0046] (Fourth Embodiment) In the fourth embodiment, a temperature control unit is further provided in the communication device or device housing having the configuration of the first to third embodiments. The fourth embodiment will be described focusing on the differences from the first embodiment, but similar differences can be applied to the second and third embodiments. The fourth embodiment has a configuration that includes a temperature control unit 412 shown in FIG. 7 in addition to the configurations of the first to fourth embodiments.

[0047] 7 is a functional block diagram showing the configuration of a communication device 400 according to the fourth embodiment. In Fig. 7, the same components as those of the communication device 100 according to the first embodiment shown in Fig. 3 are designated by the same reference numerals, and their description will be omitted. The communication device 400 has a control unit 410, a fan unit 120, and a communication unit 7.

[0048] The control unit 410 includes a state acquisition unit 411 , a model storage unit 112 , a rotation speed calculation unit 113 , and a temperature control unit 412 .

[0049] The status acquisition unit 411 has the same function as the status acquisition unit 111 of the first to third embodiments. Furthermore, the status acquisition unit 411 acquires temperature information indicating temperatures measured at one or more arbitrary locations of the communication device 400 in accordance with an instruction from the temperature control unit 412.

[0050] The model storage unit 112 has the same functions as the model storage unit 112 of the first embodiment. The model stored in the model storage unit 112 can be rewritten by the temperature control unit 412.

[0051] The temperature control unit 412 receives the temperature information acquired by the status acquisition unit 411 and determines whether the measured temperature indicated by the received temperature information is within the target temperature range. If the temperature control unit 412 determines that the measured temperature is within the target temperature range, it continues control as is. If the temperature control unit 412 determines that the measured temperature is higher than the target temperature range, it rewrites the model so that the fan rotation speed increases by a predefined amount when a calculation is performed using the same parameter value, and stores the rewritten model in the model storage unit 112 again. On the other hand, if the temperature control unit 412 determines that the measured temperature is lower than the target temperature range, it rewrites the model so that the fan rotation speed decreases by a predefined amount when a calculation is performed using the same parameter value, and stores the rewritten model in the model storage unit 112 again. The rotation speed calculation unit 113 operates in the same manner as in the first to third embodiments using the updated model.

[0052] When the fourth embodiment is applied to the second and third embodiments, the model storage unit 112 and the rotation speed calculation unit 113 shown in FIG. 7 have functions equivalent to those of the model storage unit 221 and the rotation speed calculation unit 222, the model storage unit 311 and the rotation speed calculation unit 312, or the model storage unit 361 and the rotation speed calculation unit 362.

[0053] According to the fourth embodiment, even when changes occur in the device characteristics, such as deterioration over time, or in the sensor information acquisition characteristics, the optimal model for that state can be recalculated, making it possible to continue to optimally control the fan rotation speed.

[0054] Fifth Embodiment In the fifth embodiment, a model is calculated based on past control results by a control unit. The fifth embodiment will be described focusing on the differences from the first embodiment, but similar differences can be applied to the second to fourth embodiments. The fifth embodiment has a configuration including a learning storage unit 511, a learning control unit 512, and a model calculation unit 513 shown in FIG. 8 in addition to the configurations of the first to fourth embodiments.

[0055] Fig. 8 is a functional block diagram showing the configuration of a communication device 500 according to the fourth embodiment. In Fig. 8, the same components as those of the communication device 100 according to the first embodiment shown in Fig. 3 are designated by the same reference numerals, and their description will be omitted. The communication device 500 has a control unit 510, a fan unit 120, and a communication unit 7.

[0056] The control unit 510 includes a state acquisition unit 411 , a model storage unit 112 , a rotation speed calculation unit 113 , a learning storage unit 511 , a learning control unit 512 , and a model calculation unit 513 .

[0057] The status acquisition unit 411 has the same functions as the status acquisition unit 411 of the fourth embodiment. That is, the status acquisition unit 411 acquires information on the state of external factors that affect the heat balance of the communication device 500, and outputs external factor data in which the acquired information is set. The status acquisition unit 411 also outputs measured temperature information indicating temperatures measured at one or more arbitrary locations of the communication device 500 to the learning control unit 512.

[0058] The model storage unit 112 has the same functions as the model storage unit 112 of the above-described embodiment. The model stored in the model storage unit 112 can be rewritten by the model calculation unit 513.

[0059] The rotation speed calculation unit 113 has the same function as the rotation speed calculation unit 113 of the above-described embodiment. The rotation speed calculation unit 113 further stores the calculation result of the fan rotation speed and the model used for calculating the fan rotation speed in the learning memory unit 511.

[0060] The learning memory unit 511 stores, in chronological order, one or more of the fan rotation speeds calculated in the past by the rotation speed calculation unit 113 and the model used, as well as the external factor data and measured temperature information acquired by the status acquisition unit 411.

[0061] The learning control unit 512 determines whether the measured temperature indicated by the measured temperature information acquired by the status acquisition unit 411 is within the target temperature range. If the learning control unit 512 determines that the measured temperature is outside the target temperature range, it acquires external factor data and measured temperature information at that time from the status acquisition unit 411, acquires the model currently being used and the calculated fan rotation speed from the rotation speed calculation unit 113, and stores them in the learning memory unit 511. If the measured temperature is higher than the target temperature, the learning control unit 512 instructs the fan unit 120 to increase the rotation speed by a predefined amount, and if the set temperature is lower than the target temperature, instructs the fan unit 120 to decrease the rotation speed by a predefined amount. The amount of change can be arbitrary. The learning control unit 512 also instructs the model calculation unit 513 to calculate an optimal calculation formula.

[0062] The model calculation unit 513 calculates an optimal model based on instructions from the learning control unit 512, and updates the model stored in the model storage unit 112 with the calculated model. The model calculation unit 513 acquires a model from the model storage unit 112, changes the model parameters in a predefined order, and calculates the temperature by substituting the external factor data and fan rotation speed stored in the learning storage unit 511. If the calculation result is not within the target temperature range, the model calculation unit 513 changes the model parameters and performs calculation again, and if the calculation result is within the target temperature range, updates the model stored in the model storage unit 112 with the model used at that time.

[0063] When the fifth embodiment is applied to the second and third embodiments, the model storage unit 112 and the rotation speed calculation unit 113 shown in FIG. 8 have functions equivalent to those of the model storage unit 221 and the rotation speed calculation unit 222, the model storage unit 311 and the rotation speed calculation unit 312, or the model storage unit 361 and the rotation speed calculation unit 362.

[0064] In the first to fourth embodiments, when defining a model in advance, it is necessary to perform experiments or the like using a large number of combinations of external factor states and temperatures, and to calculate each one manually to obtain the model. This requires a large amount of work for implementation. According to the fifth embodiment, assuming that the model parameter change policy is appropriate, the effort of manual calculations can be eliminated, making it possible to define an optimal model by simply repeating experiments in advance or during operation.

[0065] Sixth Embodiment In a sixth embodiment, artificial intelligence is used for fan rotation speed control as an advanced version of model-based control.

[0066] Fig. 9 is a functional block diagram showing the configuration of a communication device 600 according to the sixth embodiment. In Fig. 9, the same components as those of the communication device 500 according to the fifth embodiment shown in Fig. 8 are designated by the same reference numerals, and their description will be omitted. The communication device 600 has a control unit 610, a fan unit 120, and a communication unit 7. The control unit 610 has a state acquisition unit 411 and an artificial intelligence model unit 611.

[0067] The artificial intelligence model unit 611 learns a model that optimally controls the fan rotation speed based on input data through reinforcement learning, and controls the fan rotation speed using the learned model. The input data for the model is external factor data indicating the state of external factors obtained from the status acquisition unit 411, such as the presence or absence of devices nearby the communication device 600, the external temperature of the communication device 600, and the integrated value of the traffic volume in the communication unit 7, and the output is the fan rotation speed. The artificial intelligence model unit 611 compares the measured temperature obtained by the status acquisition unit 411 after a certain period of time with the target temperature to construct a model that optimally controls the fan rotation speed.

[0068] 10 is a flow diagram showing the model learning process of the communication device 600. The state acquisition unit 411 acquires external factor data indicating the state of external factors, which serves as input data (step S1). The artificial intelligence model unit 611 determines the fan rotation speed using the external factor data acquired in step S1 (step S2). The artificial intelligence model unit 611 outputs a rotation instruction for the determined fan rotation speed to the fan unit 120 (step S3). The fan unit 120 rotates the fan at the instructed rotation speed.

[0069] After a certain period of time has elapsed, the status acquisition unit 411 acquires measured temperature information obtained by performing temperature measurement (step S4). The artificial intelligence model unit 611 compares the measured temperature measured in step S4 with the target temperature range (step S5). The artificial intelligence model unit 611 learns an optimal control model based on the comparison result (step S6). The communication device 600 repeats the process from step S1.

[0070] According to the fifth embodiment, it is necessary to define the policy for changing the model parameters by oneself, and the study and validity of the optimal policy are issues. According to the sixth embodiment, it is possible to autonomously obtain the optimal model, thereby solving the above-mentioned issues.

[0071] Seventh Embodiment In the seventh embodiment, a configuration for outputting a notification is added to the configurations of the fourth and fifth embodiments. The seventh embodiment will be described focusing on the differences from the fifth embodiment, but similar differences can also be applied to the fourth embodiment.

[0072] Fig. 11 is a diagram showing the configuration of a communication device 700 according to the seventh embodiment. The communication device 700 shown in Fig. 11 includes a control unit 710, a fan unit 120, and a communication unit 7. The control unit 710 differs from the control unit 510 included in the communication device 500 according to the fifth embodiment shown in Fig. 8 in that the control unit 710 further includes a notification unit 711. The status acquisition unit 411, the model storage unit 112, the rotation speed calculation unit 113, the learning storage unit 511, the learning control unit 512, the model calculation unit 513, the fan unit 120, and the communication unit 7 have functions equivalent to those of the fifth embodiment.

[0073] The model storage unit 112 has the same functions as in the fifth embodiment, and also has the function of arbitrarily rewriting the structure of the model. In addition to the functions of the fifth embodiment, the model calculation unit 513 notifies the notification unit 711 of a message when the calculation result does not fall within the target temperature range even after performing calculations for all conceivable patterns. The notification unit 711 receives the message from the model calculation unit 513 and notifies people and related external systems.

[0074] In the fourth and fifth embodiments, the types of external factor data used as input are predetermined, so if the types of defined external factors are insufficient or if new external factors to be considered increase due to changes in the state of the device or the external environment, it becomes impossible to define a correct model formula. According to the seventh embodiment, it becomes possible to receive a notification from the communication device 700 and newly define separate external factors manually, by an external system, by external artificial intelligence, or the like. Therefore, even when the above-mentioned problem occurs, it becomes possible to newly define a correct model.

[0075] Eighth Embodiment In the eighth embodiment, in addition to the configurations of the first to seventh embodiments, a switching control unit is provided for switching the control mode of the fan rotation speed. The eighth embodiment will be described focusing on the differences from the seventh embodiment, but similar differences can be applied to the first to sixth embodiments.

[0076] Fig. 12 is a functional block diagram showing the configuration of a communication device 800 according to the eighth embodiment. The communication device 800 shown in Fig. 12 differs from the communication device 700 shown in Fig. 11 in that it includes a control unit 810 instead of the control unit 710. The control unit 810 differs from the control unit 710 in that it includes a rotation speed calculation unit 811 instead of the rotation speed calculation unit 113, and that it further includes a switching control unit 812.

[0077] The state acquisition unit 411, model storage unit 112, learning storage unit 511, learning control unit 512, model calculation unit 513, notification unit 711, fan unit 120, and communication unit 7 have the same functions as those in the seventh embodiment.

[0078] The rotation speed calculation unit 811 has the same functions as the rotation speed calculation unit 113 in the above-described embodiment. Furthermore, the rotation speed calculation unit 811 switches between two control modes, "measured temperature-based control" and "model-based control," based on the difference between the measured temperature acquired by the status acquisition unit 411 and the target temperature. The measured temperature-based control is controlling the fan rotation speed within a predefined change range in accordance with instructions from the switching control unit 812. That is, if the measured temperature is higher than the target temperature, the rotation speed calculation unit 811 instructs the fan unit 120 to increase the fan rotation speed by a predetermined amount, and if the measured temperature is lower than the target temperature, the rotation speed calculation unit 811 instructs the fan unit 120 to decrease the fan rotation speed by a predetermined amount. The model-based control is calculating the fan rotation speed based on the model stored in the model storage unit 112 in accordance with instructions from the switching control unit 812, and controlling the fan unit 120. Furthermore, the rotation speed calculation unit 811 arbitrarily changes the target temperature in accordance with the switching of the control mode.

[0079] The switching control unit 812 constantly monitors whether the status acquisition unit 411 and other functional blocks in the communication device 800 are operating normally. If the switching control unit 812 detects an abnormality, it instructs the rotation speed calculation unit 811 to switch to control based on the measured temperature according to the abnormality. Furthermore, if the switching control unit 812 detects recovery from the abnormality, it instructs the rotation speed calculation unit 811 to switch to control based on the model.

[0080] When the seventh embodiment is applied to the first to sixth embodiments, the model storage unit 112 and the rotation speed calculation unit 811 shown in FIG. 12 have functions equivalent to the model storage unit 112 and the rotation speed calculation unit 113, the model storage unit 221 and the rotation speed calculation unit 222, the model storage unit 311 and the rotation speed calculation unit 312, the model storage unit 361 and the rotation speed calculation unit 362, or the artificial intelligence model unit 611.

[0081] A problem with the previous embodiments was that the fan rotation speed could not be calculated correctly and appropriate cooling could not be performed if an abnormality occurred in any of the functional blocks that handle the series of flows of model calculations, including the status acquisition unit 411. The eighth embodiment has a function similar to a fail-safe that allows cooling by the fan to continue even if the model cannot be calculated, thereby solving the above problem and improving the availability of the device.

[0082] As described above, a control device that controls the rotation speed of an air-cooling fan includes a status acquisition unit, a model storage unit, and a rotation speed calculation unit. The status acquisition unit acquires the status of one or more external factors that affect the temperature inside the air-cooled device. The storage unit stores a model that calculates the fan rotation speed according to the status of the external factors. The rotation speed calculation unit uses the model to calculate the fan rotation speed based on the status of the external factors and issues instructions to the fan. The fan unit rotates or stops according to the instructions of the rotation speed calculation unit.

[0083] As described above, the control device uses a model that defines the correspondence between external factor data affecting the temperature inside the target device and the fan rotation speed to calculate the optimal fan rotation speed corresponding to the current state of external factors and control the fan. This eliminates the time lag between the occurrence of an external factor affecting the heat balance and the transition to the corresponding fan rotation speed, making it possible to completely reduce the fan rotation speed during normal operation. This reduces the power consumption of the device compared to conventional methods.

[0084] According to the above-described embodiment, the control device includes a status acquisition unit and a calculation unit. The calculation unit corresponds, for example, to the rotation speed calculation units 5, 113, 222, 312, and 811 and the artificial intelligence model unit 611 in the embodiments. The status acquisition unit acquires external factor information indicating the status of one or more external factors that affect the temperature inside the device to be air-cooled. The calculation unit calculates a control value corresponding to the external factor information acquired by the status acquisition unit using a model indicating the correspondence between the status of the external factors and a control value used to control the air-cooling device that air-cools the device, and instructs the air-cooling device to perform air-cooling using the calculated control value.

[0085] The air-cooling device may perform air cooling using a fan. For example, the air-cooling device corresponds to the fan unit 6 in the embodiment. In this case, the control value may be the fan rotation speed.

[0086] When there are multiple air-cooling devices, the calculation unit may use models of each of the multiple air-cooling devices to calculate a control value corresponding to the external factor information acquired by the status acquisition unit. The calculation unit instructs the multiple air-cooling devices to determine a control value based on the control value calculated for each model. For example, the calculation unit instructs the multiple air-cooling devices to use a control value that results in the highest fan rotation speed.

[0087] When there are multiple devices to be air-cooled inside the enclosure, the calculation unit may use a device model to calculate a control value for each of the multiple devices corresponding to the external factor information acquired by the status acquisition unit for that device. The calculation unit instructs the air-cooling device inside the enclosure to set a control value determined based on the control value calculated for each device. For example, the calculation unit instructs the air-cooling device to set a control value that results in the highest fan rotation speed.

[0088] The control device may further include an update unit that updates the model if the temperature of the air-cooled device is not within a predetermined range after receiving an instruction from the calculation unit. The update unit corresponds to, for example, the temperature control unit 412, the model calculation unit 513, and the artificial intelligence model unit 611 in the embodiments.

[0089] The control device may include a temperature control unit that, when determining that the temperature of the device to be air-cooled is higher than a predetermined target temperature range, changes the model so that a control value is calculated that increases the air cooling by the air-cooling device by a predetermined amount, and when determining that the temperature of the device to be air-cooled is lower than the predetermined target temperature range, changes the model so that a control value is calculated that decreases the air cooling by the air-cooling device by a predetermined amount.

[0090] The control device may further include a learning memory unit and a model calculation unit. The learning memory unit stores learning data that associates external factor information, control values ​​calculated by the calculation unit using the external factor information, and temperatures of the devices to be air-cooled. The model calculation unit updates the model using the learning data stored in the learning memory unit.

[0091] When an abnormality in the device to be air-cooled is detected, the calculation unit may control the air-cooling device based on the difference between the temperature of the device and the target temperature.

[0092] The control device according to this embodiment can also be realized by a computer and a program, and the program can be recorded on a recording medium or provided via a network.

[0093] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configurations are not limited to these embodiments, and include designs within the scope of the gist of the present invention.

[0094] 1 Communication device 2 Control unit 3 Status acquisition unit 4 Model storage unit 5 Rotation speed calculation unit 6 Fan unit 7 Communication unit 100 Communication device 110 Control unit 111, 111-1 to 111-3 Status acquisition unit 112 Model storage unit 113 Rotation speed calculation unit 120, 120-1 to 120-3 Fan unit 200 Device housing 210-1 to 210-3 Communication device 220 Control unit 221 Model storage unit 222 Rotation speed calculation unit 300 Communication device 310 Control unit 311 Model storage unit 312 Rotation speed calculation unit 350 Device housing 360 Control unit 361 Model storage unit 362 Rotation speed calculation unit 400 Communication device 410 Control unit 411 Status acquisition unit 412 Temperature control unit 500 Communication device 510 Control unit 511 Learning and storage unit 512 Learning control unit 513 Model calculation unit 600 Communication device 610 Control unit 611 Artificial intelligence model unit 700 Communication device 710 Control unit 711 Notification unit 800 Communication device 810 Control unit 811 Rotation speed calculation unit 812 Switching control unit

Claims

1. A control device comprising: a status acquisition unit that acquires external factor information indicating the state of one or more external factors that affect the temperature inside a device to be air-cooled; and a calculation unit that uses a model that indicates the correspondence between the state of the external factors and the control values ​​used to control the air-cooling device that air-cools the device, calculates a control value corresponding to the external factor information acquired by the status acquisition unit, and instructs the air-cooling device to perform air-cooling using the calculated control value.

2. The control device according to claim 1, wherein, when there are multiple air-cooling devices, the calculation unit uses the model of each of the multiple air-cooling devices to calculate a control value corresponding to the external factor information acquired by the status acquisition unit, and instructs the multiple air-cooling devices on the control value determined based on the control value calculated for each model.

3. The control device described in claim 1, wherein, when there are multiple devices to be air-cooled within the enclosure, the calculation unit uses the model of the device to calculate a control value for each of the multiple devices corresponding to the external factor information acquired for the device by the status acquisition unit, and instructs the air-cooling device within the enclosure to use the control value determined based on the control value calculated for each device.

4. The control device according to claim 1, further comprising an update unit that updates the model if the temperature of the device to be air-cooled is not within a predetermined range after the instruction from the calculation unit.

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