Control devices, control methods, and control programs.

Abstract

DEPCT68 The ECU of heater 10, which serves as an example of a control device, has: control section 16, Even when the heating control is stopped, it controls the power supplied to the heater. Heat in the form of a ratio of the operating voltage and current of the heater. It became higher than 0%; and the percentage obtained was 18, which was the resistance value of the heater based on... Voltage and current specifications of the heater;

Description

Control device, control method, and control program

[0001] The present disclosure relates to a control device, a control method, and a control program.

[0002] Conventionally, techniques have been disclosed in which the resistance value of a heater is calculated from the voltage and current values ​​of the heater, and an abnormality in the heater is detected based on the calculated resistance value. For example, Japanese Patent Application Laid-Open No. 2002-215246 discloses a temperature control method for a heater made of a resistance wire. In this temperature control method, the voltage value applied to the heater and the current value flowing through the heater are measured, and the power supplied to the heater is adjusted based on these measured voltage and current values, so that the heater reaches a predetermined temperature.

[0003] When the heater control device stops controlling a heater, if the output of power to the heater is stopped, the resistance value of the heater cannot be measured during the period when the output of power is stopped, and therefore an abnormality in the heater cannot be detected.

[0004] The present disclosure has been made in consideration of the above points, and provides a control device, a control method, and a control program that are capable of detecting an abnormality in a heater even when control of the heater is stopped.

[0005] The control device of the first aspect includes a control unit that controls the power supplied to the heater so that the duty ratio of the voltage value and current value of the heater is higher than 0% even when control of the heater is stopped, and a derivation unit that derives the resistance value of the heater based on the voltage value and the current value.

[0006] According to the control device of the first aspect, even when control of the heater is stopped, it is possible to detect an abnormality in the heater.

[0007] A control device of a second aspect is the control device of the first aspect, wherein the heater includes conductive fine carbon structures.

[0008] A control device of a third aspect is the control device of the second aspect, wherein the heater is a planar heater configured to include carbon nanotubes.

[0009] According to the control device of the third aspect, not only can the entire area be heated uniformly but also the heater heats up quickly, making it possible to provide a heater that is comfortable to use.

[0010] The control device of the fourth aspect is a control device of any one of the first to third aspects, and further includes an acquisition unit that acquires the environmental temperature around the heater, and a stop unit that stops control of the heater when the environmental temperature exceeds a predetermined set temperature.

[0011] According to the control device of the fourth aspect, it is possible to prevent the environmental temperature from rising excessively.

[0012] The control device of the fifth aspect is a control device of any one of the first to fourth aspects, and when the engine of a vehicle equipped with the heater is started, it controls the power supplied to the heater so that the duty ratio of the voltage value and current value of the heater is higher than 0%, even when control of the heater is stopped, and when the engine is stopped and control of the heater is stopped, it controls to cancel the supply of power to the heater.

[0013] According to the control device of the fifth aspect, when the engine of the vehicle is started, it is possible to detect an abnormality in the heater even if control of the heater is stopped.

[0014] A sixth aspect is a control method in which, even when control of a heater is stopped, a computer executes a process to control the power supplied to the heater so that the duty ratio of the voltage value and current value of the heater is higher than 0%, and derive the resistance value of the heater based on the voltage value and the current value.

[0015] A seventh aspect is a control program that causes a computer to execute a process to control the power supplied to the heater so that the duty ratio of the voltage value and current value of the heater is higher than 0% even when control of the heater is stopped, and to derive the resistance value of the heater based on the voltage value and the current value.

[0016] According to the present disclosure, even when control of a heater is stopped, an abnormality in the heater can be detected.

[0017] It is a block diagram showing an example of a hardware configuration of a vehicle according to an embodiment.It is a block diagram showing an example of a functional configuration of a heater ECU according to an embodiment.It is a flowchart showing an example of a control process according to an embodiment.

[0018] This application is based on Japanese Patent Application No. 2022-199830, filed on December 14, 2022, in Japan, the contents of which are incorporated herein by reference. The present disclosure will become more fully understood from the following detailed description. Further scope of application of the present application will become apparent from the following detailed description. However, the detailed description and specific examples are preferred embodiments of the present disclosure and are described for illustrative purposes only. From this detailed description, various changes and modifications will be apparent to those skilled in the art within the spirit and scope of the present disclosure. The applicant does not intend to dedicate any of the described embodiments to the public, and disclosed modifications and alternatives that may not literally fall within the scope of the claims are considered part of the invention under the doctrine of equivalents.

[0019] An example of an embodiment of the present disclosure will be described below with reference to the drawings. Fig. 1 shows a hardware configuration of a vehicle 100 including a heater ECU (Electronic Control Unit) 10. As shown in Fig. 1, a control device according to the present embodiment may be included in the vehicle 100. The vehicle 100 may include the heater ECU 10 as a control device, a vehicle seat 11, a power supply circuit 38, a heater 51, an engine ECU 52, and a temperature sensor 53.

[0020] The vehicle seat 11 may be configured to include multiple heaters 51 therein. Specifically, the heaters 51 may include heaters 51A, 51B, and 51C. The heaters 51A, 51B, and 51C are installed in various portions of the vehicle seat 11 and have the function of warming the body of an occupant. The heaters 51 may be configured to include conductive fine carbon structures. Specifically, the heaters 51 may be surface heaters that include carbon nanotubes. However, the heaters 51 are not limited to this example. For example, the heaters 51 may be configured to include carbon picotubes.

[0021] The power supply circuit 38 may supply power to the heater 51 based on an instruction from the control circuit 37 .

[0022] Each heater 51 is connected to the heater ECU 10 via a power supply circuit 38 .

[0023] The engine ECU 52 is an ECU that controls the engine of the vehicle 100. The engine ECU 52 can control the starting and stopping of the engine.

[0024] The temperature sensor 53 is a sensor for detecting the environmental temperature around the heater 51. The temperature sensor 53 may be connected to the heater ECU 10. The temperature sensor 53 may be attached to the heater 51 or the vehicle seat 11.

[0025] The number of heater ECUs 10, vehicle seats 11, heaters 51, and temperature sensors 53 included in the vehicle 100 is not limited to the example shown in FIG. 1 . For example, two or more heater ECUs 10 and two or more temperature sensors 53 may be included, and the vehicle seat 11 may be configured with any number of heaters 51. The vehicle 100 of this embodiment may also be provided with a plurality of vehicle seats 11. In this case, each heater 51 may be controlled by a single heater ECU 10, or each heater 51 may be controlled by a heater ECU 10 provided for each vehicle seat 11.

[0026] The heater ECU 10 has a function of controlling each heater 51 provided in the vehicle seat 11. As shown in Fig. 1 , the heater ECU 10 may include a CPU (Central Processing Unit) 31, a ROM (Read Only Memory) 33, a RAM (Random Access Memory) 35, an in-vehicle communication I / F (Interface) 36, a control circuit 37, and an input / output I / F 39. The CPU 31 corresponds to a computer according to this embodiment.

[0027] The CPU 31 , ROM 33 , RAM 35 , in-vehicle communication I / F 36 , control circuit 37 , and input / output I / F 39 may be connected to each other via an internal bus 41 so as to be able to communicate with each other.

[0028] The CPU 31 is a central processing unit that may execute various programs and control each component. That is, the CPU 31 can read programs from the ROM 33 and execute the programs using the RAM 35 as a work area. The CPU 31 can control each component and perform various arithmetic operations in accordance with the programs stored in the ROM 33.

[0029] The ROM 33 may store various programs including an operating system and various data. The ROM 33 may store a control program 200 for executing a control process, which will be described later. Note that instead of or in addition to the ROM 33, a recording medium such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive) may be provided.

[0030] The RAM 35 can temporarily store programs and data as a working area.

[0031] The in-vehicle communication I / F 36 may be an interface for connecting to the engine ECU 52 .

[0032] A power supply circuit 38 is connected to the control circuit 37. The control circuit 37 can control the power supply circuit 38.

[0033] The input / output I / F 39 may be an interface for connecting to the temperature sensor 53 .

[0034] Next, the functional configuration of the heater ECU 10 according to this embodiment will be described with reference to Fig. 2. As shown in Fig. 2, the heater ECU 10 according to this embodiment can function as an acquisition unit 12, a cancellation unit 14, a control unit 16, a derivation unit 18, and a detection unit 20 by the CPU 31 executing a control program 200 stored in the ROM 33.

[0035] The acquisition unit 12 has a function of acquiring the environmental temperature around the heater 51. Specifically, the acquisition unit 12 can acquire temperature information measured by the temperature sensor 53 via the input / output I / F 39.

[0036] The canceling unit 14 has a function of canceling control of the heater 51 when the environmental temperature exceeds a predetermined set temperature. The set temperature may be predetermined by the owner or manufacturer of the vehicle 100. Note that the canceling unit 14 continues to control the heater 51 when the environmental temperature is equal to or lower than the set temperature.

[0037] The control unit 16 has a function of controlling the power supplied to the heater 51 so that the duty ratio of the voltage value and the current value of the heater 51 is higher than 0%, even when the cancellation unit 14 has cancelled control over the heater 51. Specifically, when the cancellation unit 14 has cancelled control over the heater 51, the control unit 16 can output an instruction to the control circuit 37 so that the duty ratio of the voltage value and the current value is lower (for example, 1%) than when the cancellation unit 14 has not cancelled control over the heater 51. Hereinafter, the power supplied by the power supply circuit 38 to the heater 51 when the cancellation unit 14 has cancelled control over the heater 51 is referred to as minute power. The minute power is power that ensures a time period during which the derivation unit 18, described later, can acquire the voltage value and the current value of the heater 51. Furthermore, the power supplied by the power supply circuit 38 to the heater 51 when the cancellation unit 14 has not cancelled control over the heater 51 is referred to as normal power. Furthermore, the upper limit of the duty ratio can be set arbitrarily as long as the current is low enough that the heater 51 does not perform any work and the resistance can be calculated from the voltage and current when power is applied, and can be set to, for example, 10% or less.

[0038] In this embodiment, the control unit 16 acquires engine information indicating whether the engine of the vehicle 100 has started from the engine ECU 52. Then, when the engine of the vehicle 100 has started, the control unit 16 outputs an instruction to the control circuit 37 to output minute power to the heater 51, even if the cancellation unit 14 has stopped control of the heater 51. Furthermore, in this embodiment, when the engine of the vehicle 100 is stopped and the cancellation unit 14 has stopped control of the heater 51, the control unit 16 outputs an instruction to the control circuit 37 to cancel the supply of power to the heater 51.

[0039] In addition, the control unit 16 may output an instruction to the control circuit 37 to output minute power to the heater 51 when the stopping unit 14 has stopped control of the heater 51, regardless of whether the engine of the vehicle 100 has started or not.

[0040] The derivation unit 18 has a function of deriving the resistance value of the heater 51 based on the voltage value and current value of the heater 51. The voltage value and current value of the heater 51 are values ​​that are varied by switching the heater 51 on and off through PWM (Pulse Width Modulation) control. Specifically, the derivation unit 18 can derive the resistance value of the heater 51 by dividing the voltage value of the heater 51 obtained via the control circuit 37 by the current value of the heater 51 obtained via the control circuit 37.

[0041] The detection unit 20 detects an abnormality in the heater 51. Specifically, the detection unit 20 can detect an abnormality in the heater 51 when the resistance value derived by the derivation unit 18 is outside a predetermined range. The detection unit 20 can output an instruction to the control circuit 37 to stop powering on the heater 51 for which an abnormality has been detected. In this embodiment, the predetermined range is set to a value that is a certain percentage (e.g., 1%) lower than a predetermined resistance value and a certain percentage higher than the predetermined resistance value. In this embodiment, the resistance value previously derived by the derivation unit 108 is used as the predetermined resistance value. However, the present disclosure is not limited to the above example. For example, the predetermined resistance value may be a value predetermined by the owner or manufacturer of the vehicle 100, or a resistance value when at least one of the voltage value and the current value of the heater 51 is at the rated upper limit.

[0042] Next, an example of the operation of the heater ECU 10 according to this embodiment will be described. In the vehicle 100, a control process for the heater 51 shown in Fig. 3 is executed. Each process in the heater ECU 10 can be executed by the CPU 31 functioning as the acquisition unit 12, the cancellation unit 14, the control unit 16, the derivation unit 18, and the detection unit 20. The control process corresponds to a process executed by the CPU 31 as a computer according to the control method according to this embodiment.

[0043] 3, the CPU 31 acquires the environmental temperature around the heater 51. Specifically, the CPU 31 acquires temperature information measured by the temperature sensor 53 via the input / output I / F 39.

[0044] In step S102, the CPU 31 determines whether the environmental temperature acquired in step S101 exceeds the set temperature. If the environmental temperature exceeds the set temperature (step S102: YES), the CPU 31 proceeds to step S103.

[0045] In step S103, the CPU 31 stops controlling the heater 51 when the environmental temperature exceeds the set temperature.

[0046] In step S104, the CPU 31 determines whether or not the engine of the vehicle 100 has started. Specifically, the CPU 31 determines whether or not the engine information acquired from the engine ECU 52 indicates that the engine has started. If the engine of the vehicle 100 has started (step S104: YES), the CPU 31 proceeds to step S105.

[0047] In step S105 , the CPU 31 outputs an instruction to the control circuit 37 to supply minute power to the heater 51 .

[0048] In step S106, the CPU 31 acquires the voltage value and current value of the heater 51. Specifically, the CPU 31 acquires from the control circuit 37 the voltage value and current value that vary depending on the on / off switching by PWM control.

[0049] In step S107, the CPU 31 derives the resistance value of the heater 51 by dividing the voltage value acquired in step S106 by the current value acquired in step S106.

[0050] In step S108, the CPU 31 determines whether or not an abnormality has been detected in the heater 51. Specifically, the CPU 31 determines whether or not the resistance value calculated in step S107 is outside a predetermined range. If the CPU 31 detects an abnormality in the heater 51 (step S108: YES), the CPU 31 proceeds to step S109. On the other hand, if the CPU 31 has not detected an abnormality in the heater 51 (step S108: NO), the CPU 31 ends the control process.

[0051] In step S109, the CPU 31 outputs an instruction to the control circuit 37 to stop the power supply to the heater 51. Then, the control process ends.

[0052] Returning to step S104, if the engine of the vehicle 100 has not started (step S104: NO), the CPU 31 proceeds to step S110.

[0053] In step S110, the CPU 31 outputs an instruction to the control circuit 37 to cancel the supply of power to the heater 51. Then, the control process ends.

[0054] Returning to step S102, if the environmental temperature is equal to or lower than the set temperature (step S102: NO), the CPU 31 proceeds to step S111.

[0055] In step S111, the CPU 31 outputs an instruction to the control circuit 37 to supply normal power, and then the process proceeds to step S106.

[0056] As described above, the control unit 16 of the heater ECU 10 according to this embodiment controls the power supplied to the heater 51 so that the duty ratios of the voltage and current values ​​of the heater 51 are higher than 0%, even when the canceling unit 14 cancels control of the heater 51. The derivation unit 18 of the heater ECU 10 derives the resistance value of the heater 51 based on the voltage and current values ​​of the heater 51.

[0057] According to this embodiment, even when control of a heater 51 is suspended, it is possible to detect an abnormality in that heater 51. Furthermore, when the heater ECU 10 controls multiple heaters 51, the influence of the wiring resistance from the control board to the heaters 51 varies depending on the number of heaters 51 being controlled (i.e., the amount of current). In this case, if the heater ECU 10 stops outputting power to a heater 51 that it has suspended control of, there is a problem that the measurement results of the resistance values ​​of the other heaters 51 fluctuate. According to this embodiment, the resistance value of the heater 51 can be measured accurately without being influenced by the wiring resistance.

[0058] Furthermore, the heater 51 according to this embodiment is configured to include conductive fine carbon structures. As an example, the heater 51 according to this embodiment is a planar heater configured to include carbon nanotubes. According to this embodiment, a heater that is comfortable to use can be provided.

[0059] Furthermore, the acquisition unit 12 of the heater ECU 10 according to this embodiment acquires the environmental temperature around the heater 51. Then, the cancellation unit 14 of the heater ECU 10 cancels control of the heater 51 when the environmental temperature exceeds a predetermined set temperature. According to this embodiment, it is possible to prevent the environmental temperature from rising excessively.

[0060] Furthermore, when the engine of the vehicle 100 is started, the control unit 16 according to the present embodiment controls the power supplied to the heater 51 so that the duty ratio of the voltage value and the current value of the heater 51 is higher than 0%, even if the cancellation unit 14 has stopped control of the heater 51. When the engine is stopped and the cancellation unit 14 has stopped control of the heater 51, the control unit 16 controls to cancel the supply of power to the heater 51. According to the present embodiment, when the engine of the vehicle is started, it is possible to detect an abnormality in the heater even if control of the heater has been stopped.

[0061] In this embodiment, a heater including conductive fine carbon structures is used as an example, but the present invention can also be used to measure the resistance of a nichrome wire, which is an electric heating wire.

[0062] Furthermore, although the present embodiment has been described using a vehicle seat as an example, the heater ECU 10 can also be used for other products that can utilize heaters containing conductive micro carbon structures, such as clothing and chairs other than those for vehicles.

[0063] In the present embodiment, the detection unit 20 of the heater ECU 10 detects an abnormality in the heater 51 when the resistance value of the heater 51 is outside a predetermined range. However, this is not limiting. A detection device other than the heater ECU 10 may detect an abnormality in the heater 51 based on the resistance value of the heater 51. In this case, for example, the derivation unit 18 of the heater ECU 10 outputs the derived resistance value of the heater 51 to the detection device. Then, the detection device detects an abnormality in the heater 51 based on the output resistance value of the heater 51.

[0064] In the above embodiments, the control processing executed by the CPU after reading the software (program) may be executed by various processors other than the CPU. Examples of processors in this case include PLDs (Programmable Logic Devices) whose circuit configuration can be changed after manufacture, such as FPGAs (Field-Programmable Gate Arrays), and dedicated electrical circuits, such as ASICs (Application Specific Integrated Circuits), which are processors having a circuit configuration designed specifically to execute specific processing. Furthermore, the control processing may be executed by one of these various processors, or by a combination of two or more processors of the same or different types (e.g., multiple FPGAs, or a combination of a CPU and an FPGA). Furthermore, the hardware structure of these various processors is, more specifically, an electrical circuit that combines circuit elements such as semiconductor elements.

[0065] In the above embodiment, the control program 200 is pre-stored (installed) in a storage device, but this is not limiting. The program may be provided in a form recorded on a recording medium such as a CD-ROM, a DVD-ROM (Digital Versatile Disc Read Only Memory), or a USB (Universal Serial Bus) memory. The program may also be downloaded from an external device via a network.

[0066] All references, including publications, patent applications, and patents, cited in this specification are herein incorporated by reference to the same extent as if each reference was individually and specifically indicated to be incorporated by reference and set forth in its entirety herein.

[0067] The use of nouns and similar referents in connection with the description of this disclosure (particularly in connection with the claims that follow) shall be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The words "comprises," "has," "includes," and "comprises" shall be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise noted. The recitation of numerical ranges herein is merely intended to serve as a shorthand method for referring individually to each value falling within the range, unless otherwise indicated herein, and each value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or clearly contradicted by context. Any example or exemplary language used herein (e.g., "such as"), unless otherwise claimed, is intended merely to better illustrate the disclosure and does not pose a limitation on the scope of the disclosure. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the present disclosure.

[0068] Preferred embodiments of the disclosure are described herein, including the best mode known to the inventors for carrying out the disclosure. Variations of these preferred embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventor expects that skilled persons will apply such variations as appropriate, and intends to practice the disclosure otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, this disclosure includes any combination of the above-described elements in all variations thereof unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

DEPCT681. Integrated control device consisting of: a control section that, even when heater control is stopped, controls the power supplied to the heater in such a way that the operating ratio of the heater's voltage and current values ​​becomes greater than 0%; and an acquisition section that obtains the heater's resistance value based on the voltage and current values.

2. Control device of claim 1, in which the heater is structured to include a fine conductive carbon structure.

3. Control device of claim 2, in which the heater is a planar heater structured to include carbon nanotubes.

4. Control device of claim 1, also consisting of: an acquisition section that obtains the ambient temperature of the heater; and a stop section that stops heater control in case the ambient temperature exceeds a predetermined set temperature. 5.The control device of claim 1, which, in the event that the engine of the vehicle with a heater is started, even though the heater control is stopped, controls the power supplied to the heater in such a way that the duty ratio of the heater's voltage and current becomes greater than 0%, and, in the event that the engine is stopped and the heater control is stopped, the control affects the control to discontinue the power supply to the heater.

6. The integrated control method, by computer: even when the heater control is stopped, controls the power supplied to the heater in such a way that the duty ratio of the heater's voltage and current becomes greater than 0%; and the heater's resistance is obtained based on the voltage and current values;

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