Power supply control device, power supply control method, and computer program

Abstract

A power supply control device for a vehicle that controls power supply to a load on the basis of a temperature estimation result of an electric wire connected to the load, the power supply control device being provided with: a changing unit that changes a temperature estimation parameter in accordance with the load; and an estimation unit that estimates the temperature using the changed parameter.

Description

Technical Field

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

[0002] This application claims the priority based on Japanese application No. 2022-169155 filed on October 21, 2022, and cites all the contents described in the said Japanese application. Background Art

[0003] Conventionally, technology for preventing the occurrence of smoke in electric wires when the temperature of the electric wires rises due to a short-circuit current such as repeated on / off switching in a vehicle is widely used.

[0004] For example, Patent Document 1 discloses a power supply control device that detects the current in an electric wire when power is supplied, uses the current to estimate the current temperature of the electric wire, and compares the current temperature of the electric wire with the upper limit temperature allowed for the electric wire, thereby cutting off the current before the electric wire reaches a smoking temperature to prevent the electric wire from smoking.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2009-130944 Summary of the invention

[0008] The power supply control device involved in the embodiment of the present disclosure is a power supply control device for a vehicle that controls power supply to a load based on a temperature estimation result of an electric wire, and includes: a changing unit that changes the parameters of the temperature estimation according to the load; and an estimating unit that uses the changed parameters to perform the temperature estimation.

[0009] The power supply control device involved in the embodiment of the present disclosure is a power supply control method performed by a power supply control device for a vehicle that controls the power supply to a load using a temperature estimation result based on an electric wire, which includes: changing the parameters of the temperature estimation according to the load; and using the changed parameters to perform the temperature estimation, and turning the power supply on or off based on the result of the temperature estimation.

[0010] The computer program involved in the embodiment of the present disclosure is a computer program for controlling power supply using a power supply control device for a vehicle, wherein the power supply control device controls the power supply to a load based on a temperature estimation result of an electric wire, wherein the program causes the computer to perform the following processing: changing the parameters of the temperature estimation according to the load; performing the temperature estimation using the changed parameters; and turning the power supply on or off based on the result of the temperature estimation. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a conceptual diagram schematically showing the power supply control device according to the first embodiment mounted on a vehicle and a load connected to the power supply control device.

[0012] Figure 2 This is a functional block diagram conceptually illustrating the functional process of the microcomputer of the power supply control device.

[0013] Figure 3 This is a diagram conceptually illustrating an example of storage content stored in the storage unit.

[0014] Figure 4 This is a flowchart for explaining a process of controlling power supply based on the estimated temperature of the load-side electric wire by the power supply control device according to the first embodiment.

[0015] Figure 5 This is a conceptual diagram schematically showing a power supply control device according to Embodiment 2 mounted on a vehicle and a load connected to the power supply control device.

[0016] Figure 6 This is a conceptual diagram schematically showing a power supply control device according to Embodiment 3 mounted on a vehicle and a load connected to the power supply control device.

[0017] Figure 7 This is a flowchart for explaining the process of changing electric line parameters in the power supply control device according to the fourth embodiment. DETAILED DESCRIPTION

[0018] [Problems to be Solved by the Present Disclosure]

[0019] However, since the current value used for driving varies depending on the load, the power supply wire connected to the load also needs to be changed according to the load. In addition, the parameters used for estimating the temperature of the wire also vary according to the wire, so it is necessary to prepare a power supply control device with different parameters for each load in advance. That is, as the variety of products of the power supply control device increases, the manufacturing cost increases.

[0020] Furthermore, when the connected wires are replaced due to changes or additions to the load after the vehicle leaves the factory, the parameters used for estimating the wire temperature remain the parameters at the time of vehicle shipment, and there is a problem that the wire temperature cannot be estimated accurately.

[0021] However, the power supply control device of Patent Document 1 does not study such a problem and cannot solve it.

[0022] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a power supply control device, a power supply control method, and a computer program capable of accurately estimating the temperature of an electric wire for a plurality of types of loads having different driving current values.

[0023] [Effects of the present disclosure]

[0024] According to the present disclosure, it is possible to accurately estimate the temperature of the electric wire even for a plurality of types of loads having different driving current values.

[0025] [Description of Embodiments of the Invention]

[0026] First, the embodiments of the present disclosure will be described by way of examples. In addition, at least a part of the embodiments described below may be arbitrarily combined.

[0027] (1) A power supply control device according to an embodiment of the present disclosure controls power supply to a load based on a temperature estimation result of an electric wire, and includes: a changing unit that changes a parameter of the temperature estimation according to the load; and an estimating unit that performs the temperature estimation using the changed parameter.

[0028] In this embodiment, for example, when the load is replaced, the changing unit changes the temperature estimation parameters according to the replaced load, and the estimating unit performs the temperature estimation using the changed parameters. Therefore, even when the driving current value of the replaced load is different, the correct wire temperature can be estimated.

[0029] (2) In the power supply control device according to the embodiment of the present disclosure, the power supply control device includes an acquisition unit that acquires specific information related to the parameter, and the change unit changes the parameter based on the specific information acquired by the acquisition unit.

[0030] In this embodiment, for example, when the load is replaced, the acquisition unit acquires specific information corresponding to the replaced load, and the change unit changes the parameter based on the load information acquired by the acquisition unit. Therefore, even when the load is replaced, the correct wire temperature can be estimated.

[0031] (3) In the power supply control device according to the embodiment of the present disclosure, the acquisition unit acquires the specific information from outside the vehicle via a reception unit provided in the vehicle.

[0032] In this embodiment, for example, when the load is replaced, the acquisition unit acquires specific information corresponding to the replaced load from the outside of the vehicle via the receiving unit, and the changing unit changes the parameter based on the specific information acquired by the acquisition unit. Therefore, even when the load is replaced, the correct wire temperature can be estimated.

[0033] (4) In the power supply control device involved in the embodiment of the present disclosure, the power supply control device includes a storage unit, which stores the specific information corresponding to multiple types of loads that can be connected to the device, the acquisition unit obtains the specific information from a communication unit related to the load, and the change unit changes the parameter based on the specific information obtained from the communication unit and the storage content of the storage unit.

[0034] In this embodiment, for example, when the load is replaced, the acquisition unit acquires specific information corresponding to the replaced load from the communication unit, and the change unit changes the parameter based on the specific information acquired by the acquisition unit and the storage content of the storage unit. Therefore, even when the load is replaced, the correct wire temperature can be estimated.

[0035] (5) In the power supply control device according to the embodiment of the present disclosure, the specific information is at least one of a current value for driving the load, a current value related to a switch that turns the power supply on or off, and information related to the electric wire.

[0036] In this embodiment, the specific information may be, for example, a current value for driving the load, a current value flowing through a switch for turning on or off the power supply, or information related to the wire (for example, diameter).

[0037] (6) In the power supply control device involved in the embodiment of the present disclosure, the specific information includes a current value for driving the load, and the power supply control device comprises: a storage unit, storing the current value of each of a plurality of types of loads that can be connected to the device; and a current detection unit, detecting the current value when the device and the load are powered on for the first time, and the changing unit changes the parameter based on the current value obtained from the current detection unit and the storage content of the storage unit.

[0038] In this embodiment, for example, when the load is replaced, the acquisition unit acquires the current value for driving the replaced load from the current detection unit, and the change unit changes the parameter based on the current value acquired by the acquisition unit and the storage content of the storage unit. Therefore, even when the load is replaced, the correct wire temperature can be estimated.

[0039] (7) In the power supply control device involved in the embodiment of the present disclosure, the acquisition unit acquires the specific information via a communication unit related to the load, and the specific information includes a current value for driving the load. The power supply control device comprises: a current detection unit, which detects the current value when the device and the load are powered on for the first time; and a determination unit, which determines whether communication with the communication unit is possible. The acquisition unit acquires the specific information from the communication unit or acquires the current value from the current detection unit based on the determination result of the determination unit.

[0040] In this embodiment, for example, when the load is replaced, the determination unit determines whether communication with the communication unit is possible, and when it is determined that communication is possible, the acquisition unit acquires the specific information from the communication unit, and when it is determined that communication is not possible, the acquisition unit acquires the current value from the current detection unit. Therefore, it is also possible to cope with a situation where the communication unit related to the replaced load does not exist, or a situation where the communication unit exists but the acquisition unit cannot acquire specific information from the communication unit for some reason.

[0041] (8) In the power supply control device according to the embodiment of the present disclosure, the acquisition unit acquires the specific information via a communication unit associated with the load, and when the acquisition unit acquires the specific information from the reception unit, the acquisition unit invalidates the specific information acquired from the communication unit.

[0042] In this embodiment, for example, when the load is replaced, the specific information is obtained via the communication unit related to the load, and when the specific information is obtained from an operator or the like via the receiving unit, the specific information obtained by the obtaining unit from the communication unit is invalidated. The changing unit changes the parameters using the specific information from the receiving unit, and the estimating unit performs the temperature estimation using the changed parameters. Therefore, the accuracy of the temperature estimation can be improved.

[0043] (9) In the power supply control device involved in the embodiment of the present disclosure, the power supply control device includes a semiconductor switch that turns the power supply on or off, and the semiconductor switch has an on-resistance corresponding to the maximum current value among the current values ​​used to drive multiple types of loads that can be connected to the device.

[0044] In the present embodiment, since the semiconductor switch has an on-resistance corresponding to the maximum current value, it is possible to cope with any load in which the semiconductor switch and the output wire are replaced.

[0045] (10) The power supply control method involved in the embodiment of the present disclosure is a power supply control method performed by a power supply control device for a vehicle that controls the power supply to a load based on a temperature estimation result of an electric wire, which includes: changing the parameters of the temperature estimation according to the load; using the changed parameters to perform the temperature estimation, and turning the power supply on or off based on the result of the temperature estimation.

[0046] (11) The computer program involved in the embodiment of the present disclosure is a computer program for controlling power supply using a power supply control device for a vehicle, wherein the power supply control device controls the power supply to a load based on a temperature estimation result of an electric wire, wherein the program causes the computer to perform the following processing: changing the parameters of the temperature estimation according to the load; performing the temperature estimation using the changed parameters; and turning the power supply on or off based on the result of the temperature estimation.

[0047] In this embodiment, for example, when the load is replaced, the temperature estimation parameters are changed according to the replaced load, and the temperature estimation is performed using the changed parameters. Therefore, even when the current value for driving the replaced load is different, the correct wire temperature can be estimated.

[0048] [Details of the embodiments of the present invention]

[0049] Hereinafter, the power supply control device, power supply control method and computer program involved in the embodiments of the present disclosure are described with reference to the accompanying drawings. In addition, the present invention is not limited to these examples, but is shown by the scope of protection claimed, and is intended to include all changes within the meaning and scope equivalent to the scope of protection claimed.

[0050] (Implementation Method 1)

[0051] Conventionally, in a vehicle, a power supply control device is interposed between a power source such as a battery and loads such as seats and doors. The power supply control device is a device that turns on or off the power supply from the power source to the load as needed.

[0052] The power supply control device includes a fuse for cutting off power supply to the load. For example, when the temperature of the electric wire rises excessively due to a short-circuit current such as repeated on / off switching, the fuse cuts off power supply to the load to prevent smoke from occurring in the electric wire.

[0053] In recent years, power supply control devices include semiconductor switches as the fuses, estimate the temperature of the wire when energized, and compare the estimated wire temperature with the allowable upper limit temperature of the wire, thereby cutting off power supply before the wire reaches a smoking temperature.

[0054] As a method of estimating the temperature of an electric wire when current is supplied, there is known a method of estimating the temperature of the electric wire from the sum of the heat generation and heat dissipation of the electric wire. Specifically, the temperature of the electric wire can be estimated by detecting the current of the electric wire when current is supplied using the following equation 1.

[0055] ΔTw=A×I 2 ×{1-exp(-t / τ)}…Formula 1,

[0056] ΔTw: The temperature rise of the wire from the reference temperature (°C);

[0057] I: Detected current value (A);

[0058] τ: thermal time constant of the wire (s) (fixed value);

[0059] t: time (s);

[0060] A: Wire parameters.

[0061] Here, A is a characteristic of the wire connected to the load corresponding to the power supply control device. That is, the wire parameter A changes according to the wire connected to the load. For example, the wire parameter A is a fixed value depending on Rw (wire resistance (Ω)) and Rthw (wire thermal resistance (°C / W)).

[0062] However, the type of wire connected to the load, such as the thickness (diameter) of the wire, is determined according to the driving current value required to drive the load. That is, the larger the driving current value, the larger the diameter of the wire is required. In addition, the allowable upper limit temperature of the wire varies according to the type of wire. Moreover, the driving current value also varies depending on whether the load is a seat or a door. Furthermore, even for the same seat, the driving current value varies depending on whether there is a USB (Universal Serial Bus) charging function, a heater function, an electric seat function, etc.

[0063] As described above, the type of electric wire (electric wire diameter) is determined according to the load. Therefore, when the electric power supply control device is mounted on a vehicle, the setting of the electric wire parameter A of the electric power supply control device is determined according to the load connected to the electric power supply control device.

[0064] In addition, the diameter of the wire connected to the load needs to be different depending on the load to be connected, and semiconductor switches with different capacities need to be selected in the power supply control device. In other words, it is necessary to prepare a plurality of types of power supply control devices with different capacities of semiconductor switches in advance, which increases the variety of power supply control devices.

[0065] Furthermore, it is assumed that after the vehicle is equipped with the power supply control device, that is, after the vehicle is shipped from the factory, the function of the load or the load itself is added. In this case, as the load function is added or the load itself is added, the above-mentioned driving current value becomes larger, so it is necessary to change to a wire with a larger wire diameter. That is, since the wire (wire diameter) has changed, although the wire parameter A of the above-mentioned formula 1 has actually changed, the wire parameter A of the power supply control device still remains in the state set at the factory, and the power supply control device cannot accurately estimate the temperature of the wire, which may cause malfunction.

[0066] On the other hand, the power supply control device according to the first embodiment described below is configured to solve the above-mentioned problems.

[0067] Figure 1 This is a conceptual diagram schematically showing the power supply control device 10 according to the first embodiment mounted on the vehicle C and a load 52 connected to the power supply control device 10 . The load 52 is, for example, at least one of a USB charger, a heater, and a power seat motor provided on the seat 50 .

[0068] The vehicle C includes a power supply 20, a power supply control device 10, and a seat 50. The seat 50 has a load 52, and the power supply control device 10 is interposed between the power supply 20 and the load 52. In other words, the power supply 20 is connected to the load 52 via the power supply control device 10.

[0069] A connector 40 is provided between the power supply control device 10 and the seat 50 (load 52). The power supply control device 10 and the connector 40 are connected by a power supply wire L1 (output wire), and the connector 40 and the load 52 are connected by a power supply wire L3. For example, the connector 40 is provided at a boundary between the floor and the seat 50 in the vehicle C, the upstream side of the connector 40 is the power supply 20 side, and the downstream side of the connector 40 is the load side. Hereinafter, the wire L1 is also referred to as the power supply side wire L1, and the wire L3 is also referred to as the load side wire L3.

[0070] The wire diameter of the load-side wire L3 is less than the wire diameter of the power-side wire L1. Specifically, the power-side wire L1 has a wire diameter corresponding to the driving current value of the load with the largest driving current value among all the loads that are expected to be connected to the power supply control device 10. For example, when the power supply control device 10 can connect loads 1 to 4 with different driving current values ​​and the driving current value of load 4 is the largest, the power-side wire L1 has a wire diameter corresponding to the driving current value of load 4.

[0071] Therefore, as described above, when a load function is added or a load itself is added, the load-side electric wire L3 also needs to be replaced accordingly, but the power-side electric wire L1 does not need to be replaced.

[0072] The power supply control device 10 and the connector 40 are connected via a communication line L2. Hereinafter, the communication line L2 is also referred to as a power supply side communication line L2.

[0073] The power supply side communication line L2 is connected to a receiving unit 30 that receives input of load information (specific information) from the outside of the vehicle C. Here, the so-called load information is information related to the wire parameter A, such as information that specifies the load 52 connected to the power supply control device 10. Specifically, the load information may be data indicating the model of the load 52, data indicating the above-mentioned drive current value related to the load 52, or data indicating the wire diameter of the load-side wire L3 corresponding to the drive current value. In addition, the load information may also be data indicating Rw and Rthw.

[0074] The receiving unit 30 receives input of load information when the vehicle C is shipped, or receives input of load information from a vehicle maintenance provider such as a regular dealer who performs maintenance work on the vehicle C such as replacement of the ECU.

[0075] Furthermore, the receiving unit 30 may be configured to include a communication unit (not shown) and to be capable of receiving the load information from outside the vehicle C through wireless communication using OTA (Over The Air) technology.

[0076] In the following, for convenience of description, it is assumed that the receiving unit 30 receives input of load information, which is the above-mentioned drive current value related to the load 52 , from a vehicle repairer.

[0077] The power supply control device 10 includes a microcomputer 11, an IPS (Intelligence Power Switch) 13, and an I / O (Input Output Interface) 12. The IPS 13 is interposed between the power supply 20 and the I / O 12.

[0078] The I / O 12 is connected to the power supply side wire L1 and the power supply side communication line L2. That is, the current flowing from the power supply 20 to the I / O 12 via the IPS 13 flows to the power supply side wire L1. In addition, the load information received by the receiving unit 30 is sent to the I / O 12 via the power supply side communication line L2, and is sent from the I / O 12 to the microcomputer 11.

[0079] The IPS 13 includes a switching element 131 and a current detection circuit 132 .

[0080] The switch element 131 is a semiconductor switch element such as an n-channel MOSFET, and turns on or off the current from the power supply 20 to the load 52, that is, the current flowing from the power supply 20 to the load 52 when the load 52 is powered on (hereinafter referred to as the power-on current I). The switch element 131 turns on or off the above-mentioned power-on current I according to the instruction of the microcomputer 11.

[0081] As described above, the power supply side electric wire L1 has an electric wire diameter corresponding to the expected maximum load drive current value, and therefore the switching element 131 also has an on-resistance corresponding to the expected maximum load drive current value.

[0082] The current detection circuit 132 is, for example, a sensing MOSFET, and detects the current value of the current I when the power is turned on, and transmits the current value to the microcomputer 11 .

[0083] Figure 2 This is a functional block diagram conceptually illustrating the functional process of the microcomputer 11 of the power supply control device 10 .

[0084] The microcomputer 11 includes a storage unit 111, an estimation unit 112, a change unit 113, an acquisition unit 114, an instruction unit 115, and a determination unit 116. In other words, the microcomputer 11 has a processing circuit that functions as the storage unit 111, the estimation unit 112, the change unit 113, the acquisition unit 114, the instruction unit 115, and the determination unit 116.

[0085] The storage unit 111 stores the above-mentioned Expression 1. In addition, a plurality of types of loads connectable to the power supply control device 10 are stored in association with the above-mentioned load information for each load.

[0086] Figure 3 This is a diagram conceptually illustrating an example of the storage content stored in the storage unit 111 .

[0087] For example, as described above, it is assumed that loads 1 to 4 having different drive current values ​​can be connected to the power supply control device 10. In this case, the storage unit 111 stores the range of the drive current value and the wire parameter A in correspondence with each of loads 1 to 4. In the following, it is assumed that the wire parameter A has the relationship of "A=Rw×Rthw". That is, the wire parameter A is the product of the wire resistance and the wire thermal resistance of the load-side wire.

[0088] The storage unit 111 stores the upper limit temperature in association with each of the loads 1 to 4. Here, the upper limit temperature is an upper limit temperature allowed for each load-side electric wire L3 determined according to the load.

[0089] The estimating unit 112 estimates the temperature of the load-side electric wire L3. That is, the estimating unit 112 estimates the temperature of the load-side electric wire L3 using the above-mentioned formula 1. Specifically, the estimating unit 112 estimates the temperature of the load-side electric wire L3 using the reference temperature at the start of temperature estimation set by a reference temperature setting circuit (not shown) and formula 1.

[0090] In more detail, the current detection circuit 132 detects the current value of the current I supplied to the load 52 via the load-side wire L3 at predetermined intervals, and the estimation unit 112 calculates the temperature rise (ΔTw) of the load-side wire L3 from the reference temperature within a predetermined time caused by the detected current I, and adds the temperature rise to the above-mentioned reference temperature to estimate the temperature of the load-side wire L3.

[0091] The acquisition unit 114 acquires load information related to the load 52 from outside the power supply control device 10. The acquisition unit 114 monitors the I / O 12 and acquires the load information sent from the receiving unit 30. For example, when the receiving unit 30 receives data indicating a drive current value related to the load 52 from a vehicle repairer, the receiving unit 30 sends the received drive current value to the I / O 12. The I / O 12 sends the received drive current value to the acquisition unit 114.

[0092] The changing unit 113 changes the parameter related to the temperature estimation of the load-side electric wire L3 according to the load 52. For example, when the acquiring unit 114 acquires the load information related to the load 52 from the outside of the power supply control device 10, the changing unit 113 changes the electric wire parameter A based on the load information acquired by the acquiring unit 114 and the storage content of the storage unit 111. When the electric wire parameter A is changed by the changing unit 113, the estimating unit 112 estimates the temperature of the load-side electric wire L3 using the changed electric wire parameter A.

[0093] The determination unit 116 compares the temperature of the load side wire L3 estimated by the estimation unit 112 (hereinafter referred to as the estimated temperature of the load side wire L3) with the upper limit temperature stored in the storage unit 111 to determine whether the estimated temperature of the load side wire L3 is above the upper limit temperature.

[0094] When the determination unit 116 determines that the estimated temperature of the load-side electric wire L3 is equal to or higher than the upper limit temperature, the instruction unit 115 instructs the switching element 131 of the IPS 13 to turn off the energizing current I.

[0095] As described above, the seat 50 is connected to the connector 40 via the load-side electric wire L3. The seat 50 includes the switch 51 and the load 52. The switch 51 is interposed between the connector 40 and the load 52.

[0096] Hereinafter, processing performed by the power supply control device 10 according to the first embodiment when the load 52 is changed in the vehicle C will be described.

[0097] Figure 4 This is a flowchart for explaining a process of controlling power supply based on the estimated temperature of the load-side electric wire L3 by the power supply control device 10 according to the first embodiment.

[0098] For example, a vehicle repairer may replace the load 52 provided on the seat 50 of the vehicle C from the load 1 to the load 2 having a larger driving current value as needed. The vehicle repairer first turns off the switch 51, then replaces the load 1 with the load 2, and then turns on the switch 51. In this case, as the load 52 is changed, the driving current value increases, so the vehicle repairer also changes the load-side electric wire L3 to the load-side electric wire L3 having a larger electric wire diameter.

[0099] Since the electric wire (electric wire diameter) has changed, the electric wire parameter A of the above-mentioned formula 1 also needs to be changed. Therefore, the vehicle repairer inputs the load information of the new load 52 after the change from the receiving unit 30. For example, the vehicle repairer inputs the driving current value (data) related to the new load 52, and the receiving unit 30 accepts it. (Step S101).

[0100] When receiving the driving current value related to the new load 52 from the vehicle repairer, the receiving unit 30 transmits the received driving current value to the I / O 12 , and the acquiring unit 114 acquires the driving current value via the I / O 12 (step S102 ).

[0101] In this way, when the acquisition unit 114 acquires the drive current value related to the new load 52, the change unit 113 changes the electric wire parameter A based on the drive current value acquired by the acquisition unit 114 and the storage content of the storage unit 111 (step S103).

[0102] In this example, since the load 1 is changed to the load 2, the driving current value acquired by the acquisition unit 114 is within the range of 5A to 10A. Therefore, the change unit 113 changes the driving current value based on the value stored in the storage unit 111. Figure 3 , replace the wire parameter A in Formula 1 from the current wire parameter A corresponding to load 1 to the wire parameter A corresponding to load 2.

[0103] Thereafter, the current detection circuit 132 detects the current value of the energizing current I supplied to the load 52 via the load-side electric wire L3 (step S104 ), and transmits the detected current value of the energizing current I to the microcomputer 11 .

[0104] When receiving the current value of the energizing current I, the estimating unit 112 estimates the new temperature of the load side electric wire L3 using the current value of the energizing current I and the above-mentioned equation 1 with the modified electric wire parameter A (step S105). The estimation of the temperature of the load side electric wire L3 has been described above, and the detailed description is omitted.

[0105] When the temperature of the load-side electric wire L3 is estimated, the determination unit 116 determines whether the estimated temperature of the load-side electric wire L3 is equal to or higher than the upper limit temperature based on the upper limit temperature stored in the storage unit 111 (step S106). When the determination unit 116 determines that the estimated temperature of the load-side electric wire L3 is lower than the upper limit temperature (step S106: No), the process returns to step S104. For example, when the determination unit 116 determines that the estimated temperature of the load-side electric wire L3 is lower than the upper limit temperature, the process may return to step S104 after a predetermined time has passed.

[0106] On the other hand, when the determination unit 116 determines that the estimated temperature of the load side electric wire L3 is equal to or higher than the upper limit temperature (step S106 : Yes), the instruction unit 115 instructs the switching element 131 of the IPS 13 to turn off the energizing current I (step S107 ).

[0107] Through the above processing, as described above, the power supply control device 10 of the first embodiment estimates the temperature of the load side electric wire L3 using the load information of the new load 52 when the load 52 is changed. Therefore, even when the load 52 is changed, the temperature of the load side electric wire L3 can be accurately estimated. Therefore, when the function of the load 52 of the vehicle C is added after factory shipment or the load 52 itself is added, it is possible to prevent the occurrence of smoke in the load side electric wire L3.

[0108] As described above, when load 52 is changed, power supply control device 10 according to Embodiment 1 changes existing power line parameter A to power line parameter A corresponding to new load 52 using load information of new load 52 received from outside power supply control device 10 via receiving unit 30 .

[0109] Therefore, it is possible to cope with replacement of the load 52 with a different type, and it is not necessary to prepare in advance the power supply control device 10 corresponding to a plurality of types of loads 52 connectable to the power supply control device 10 , respectively, thereby reducing the manufacturing cost of the power supply control device 10 .

[0110] (Implementation Method 2)

[0111] Figure 5This is a conceptual diagram schematically showing a power supply control device 10 according to Embodiment 2 mounted on a vehicle C and a load 52 connected to the power supply control device 10 . Similar to Embodiment 1, the vehicle C includes a power source 20 , a power supply control device 10 , and a seat 50 , but does not include a receiving unit 30 .

[0112] The power supply control device 10 is interposed between the power supply 20 and the load 52. In addition, a connector 40 is interposed between the power supply control device 10 and the seat 50. The power supply 20, the power supply control device 10, and the connector 40 are the same as those in the first embodiment, and detailed description thereof is omitted.

[0113] On the other hand, the seat 50 is connected to the connector 40 via a load-side electric wire L3 for power supply. In addition, the seat 50 and the connector 40 are connected via a communication line L4. That is, in the power supply control device 10 of the second embodiment, the power supply control device 10 and the connector 40 are connected via the power supply side communication line L2 on the upstream side of the connector 40, and the connector 40 and the seat 50 are connected via the communication line L4 on the downstream side of the connector 40. Hereinafter, the communication line L4 is also referred to as the load-side communication line L4.

[0114] The seat 50 has an ECU (Electronic Control Unit) 53 and a load 52. The ECU 53 (communication unit) is between the connector 40 and the load 52. That is, the ECU 53 and the connector 40 are connected by a load-side electric wire L3 and a load-side communication line L4. In other words, the ECU 53 can communicate with the power supply control device 10 via the load-side communication line L4, the connector 40, and the power-side communication line L2.

[0115] The ECU 53 performs energization control on the load 52 , etc. The ECU 53 also stores load information that specifies the load 52 , and transmits the load information to the power supply control device 10 in response to a request from the power supply control device 10 , as described later.

[0116] The load information may be, for example, data indicating the model of the load 52, data indicating the above-mentioned drive current value related to the load, data indicating the wire diameter of the load-side wire L3 corresponding to the drive current value, or data indicating Rw and Rthw. For convenience, the following description will be given by taking the case where the load information is data indicating the drive current value as an example.

[0117] For example, a vehicle repairer may replace the load 52 provided on the seat 50 of the vehicle C from the load 1 to the load 2 having a larger driving current value as needed. In this case, since the driving current value increases with the change of the load 52, the vehicle repairer also changes the load-side wire L3 to the load-side wire L3 having a larger wire diameter.

[0118] Hereinafter, a description will be given of the processing performed by the power supply control device 10 according to the second embodiment when the load 52 is changed in the vehicle C as described above.

[0119] When the load 52 is changed from load 1 to load 2, the microcomputer 11 of the power supply control device 10 requests the ECU 53 of the seat 50 to send the load information of the load 52. In response, the ECU 53 sends the load information of the load 52 to the power supply control device 10. At this time, the ECU 53 can send the load information (driving current value) of the load 52 stored in the device to the power supply control device 10, or detect the current value of the power-on current I flowing through the device and send it to the power supply control device 10.

[0120] When data indicating the driving current value of the load 52 is transmitted from the ECU 53 of the seat 50, the power supply control device 10 performs the same operation as in the first embodiment. Figure 4 The processing of steps S102 to S107.

[0121] That is, the acquisition unit 114 acquires the driving current value from the ECU 53 via the I / O 12, and the change unit 113 changes the wire parameter A based on the driving current value acquired by the acquisition unit 114 and the storage content of the storage unit 111. After that, the current detection circuit 132 detects the current value of the energizing current I supplied to the load 52 via the load-side wire L3, and the estimation unit 112 estimates the new temperature of the load-side wire L3 using the current value of the energizing current I and the above-mentioned formula 1 in which the wire parameter A is changed. In addition, the determination unit 116 estimates the temperature of the new load-side wire L3 based on the above-mentioned upper limit temperature stored in the storage unit 111 (refer to Figure 3 ), determines whether the estimated temperature of the load-side wire L3 is above the above-mentioned upper limit temperature. When the determination unit 116 determines that the estimated temperature of the load-side wire L3 is above the above-mentioned upper limit temperature, the indication unit 115 instructs the switching element 131 of the IPS13 to disconnect the current I.

[0122] Due to the above-described structure, the power supply control device 10 of the second embodiment is also similar to the first embodiment. Even if the function of the load 52 of the vehicle C is added after factory shipment or the load 52 itself is added, it is possible to accurately estimate the temperature of the load-side wire L3, thereby preventing the occurrence of smoke in the load-side wire L3.

[0123] In addition, when the load 52 is changed, in response to this, the existing wire parameter A is changed to the wire parameter A corresponding to the new load 52. Therefore, it is possible to cope with the replacement of the load 52 to a different type, and it is not necessary to prepare the power supply control device 10 corresponding to the multiple types of loads 52 that can be connected to the power supply control device 10 in advance, which can reduce the manufacturing cost of the power supply control device 10.

[0124] In the above, the case where the power supply control device 10 according to the second embodiment does not include the receiving unit 30 and only acquires the load information of the load 52 from the ECU 53 is described as an example, but the present invention is not limited thereto and may be configured to further include the receiving unit 30 .

[0125] Thus, when the power supply control device 10 includes both the ECU 53 and the receiving unit 30, the load information is acquired preferentially through the receiving unit 30. For example, when the acquiring unit 114 of the power supply control device 10 acquires the load information from the outside of the vehicle C through the receiving unit 30, the load information acquired from the ECU 53 is invalidated.

[0126] That is, the temperature of the load-side electric wire L3 is estimated by preferentially using the load information received from the vehicle repairer or the load information received via OTA. Therefore, the accuracy of the temperature estimation can be improved.

[0127] The same parts as those in Implementation 1 are denoted by the same reference numerals and detailed descriptions thereof are omitted.

[0128] (Implementation 3)

[0129] Figure 6 This is a conceptual diagram schematically showing a power supply control device 10 according to Embodiment 3 installed in a vehicle C and a load 52 connected to the power supply control device 10. As in Embodiment 1, the vehicle C includes a power supply 20, a power supply control device 10, and a seat 50, but does not include a receiving unit 30. The rest is the same as in Embodiment 1, and detailed description is omitted.

[0130] For example, a vehicle repairer may replace the load 52 provided on the seat 50 of the vehicle C from the load 1 to the load 2 having a larger driving current value as needed. In this case, since the driving current value increases with the change of the load 52, the vehicle repairer also changes the load-side wire L3 to the load-side wire L3 having a larger wire diameter.

[0131] Hereinafter, a description will be given of the processing performed by the power supply control device 10 according to the third embodiment when the load 52 is changed in the vehicle C as described above.

[0132] When the load 1 is replaced with the load 2, the vehicle repairer turns on the switch 51 after replacing the load 1 with the load 2. Thus, the power supply from the power source 20 to the load 52 can be performed.

[0133] For example, when the engine of vehicle C is started, current I flows from power supply 20 to load 52. Power supply control device 10 of embodiment 3 changes electric wire parameter A based on the current value of current I when power is first supplied to load 52 (hereinafter referred to as initial power supply) and the storage content of storage unit 111.

[0134] That is, when the power supply control device 10 and the load 52 are powered on for the first time, the current detection circuit 132 detects the current value of the power-on current I and sends the detected current value of the power-on current I to the microcomputer 11 (the acquisition unit 114). Thus, the acquisition unit 114 acquires the current value of the power-on current I at the time of the first power-on as load information. Hereinafter, the current value of the power-on current I acquired by the acquisition unit 114 is referred to as the acquired power-on current I (acquired current value).

[0135] When the current detection circuit 132 sends the acquired current I, the microcomputer 11 performs the same operation as in the first embodiment. Figure 4 The processing of steps S102 to S107.

[0136] That is, the acquisition unit 114 acquires the current I from the current detection circuit 132, and the change unit 113 changes the electric wire parameter A based on the current I acquired by the acquisition unit 114 and the storage content of the storage unit 111. That is, the change unit 113 replaces the current electric wire parameter A with the storage content of the storage unit 111 (refer to Figure 3 ), the wire parameter A corresponding to the range of driving current values ​​to which the current I is obtained.

[0137] After that, the estimation unit 112 estimates the new temperature of the load-side electric wire L3 using the above-mentioned formula 1 obtained by obtaining the current I and the changed electric wire parameter A. Furthermore, the determination unit 116 determines whether the estimated temperature of the load-side electric wire L3 is higher than the above-mentioned upper limit temperature based on the above-mentioned upper limit temperature stored in the storage unit 111. When the determination unit 116 determines that the estimated temperature of the load-side electric wire L3 is higher than the above-mentioned upper limit temperature, the instruction unit 115 instructs the switch element 131 of the IPS 13 to turn off the current I.

[0138] Due to the above structure, the power supply control device 10 of the third embodiment can accurately estimate the temperature of the load-side electric wire L3 even if the load 52 of the vehicle C is changed after factory shipment, similar to the first embodiment, thereby preventing the load-side electric wire L3 from smoking.

[0139] In addition, when the load 52 is changed, the existing wire parameter A is changed to the wire parameter A corresponding to the new load 52 in response to this. Therefore, it is not necessary to prepare the power supply control device 10 corresponding to the multiple types of loads 52 that can be connected to the power supply control device 10 in advance, and the manufacturing cost of the power supply control device 10 can be reduced.

[0140] The same parts as those in Implementation 1 are denoted by the same reference numerals and detailed descriptions thereof are omitted.

[0141] (Implementation 4)

[0142] As described above, in the second embodiment, an example of obtaining load information (driving current value) from the ECU 53 to change the wire parameter A is described, and in the third embodiment, an example of obtaining load information (obtaining the energizing current I) from the current detection circuit 132 at the time of the first power-on to change the wire parameter A is described, but the present invention is not limited to these. For example, it is also possible to configure the load information acquisition source to be changed according to the situation.

[0143] Figure 7 This is a flowchart for explaining the process of changing the electric line parameter A in the power supply control device 10 according to the fourth embodiment.

[0144] In the power supply control device 10 of the fourth embodiment, the acquisition unit 114 is configured to be able to acquire load information (drive current value) from the ECU 53, and also to be able to acquire load information (acquire the energized current I) from the current detection circuit 132. Figure 5 Similarly, the current detection circuit 132 is provided, and the seat 50 including the ECU 53 and the load 52 is connected. Figure 5 The explanation has already been given, and the detailed explanation will be omitted.

[0145] For example, it is assumed that a vehicle repairer replaces the load 52 of the seat 50 of the vehicle C as needed. As the load 52 is replaced, the load-side electric wire L3 is also changed to a load-side electric wire L3 with a larger electric wire diameter.

[0146] After the replacement of the load 52 by the vehicle repairer is completed, the determination unit 116 of the power supply control device 10 determines whether communication with the ECU 53 of the load 52 is possible (step S201). In other words, the determination unit 116 determines whether the ECU 53 of the load 52 exists.

[0147] Specifically, the microcomputer 11 transmits a signal requesting a response to the seat 50 side, and monitors whether the I / O 12 receives a response signal corresponding to the request within a predetermined time period.

[0148] When the response signal is received within the prescribed time, the determination unit 116 determines that it is possible to communicate with the ECU 53 of the load 52 (step S201: Yes), and the microcomputer 11 requests the ECU 53 of the seat 50 to send the load information of the load 52. In response to the request, the ECU 53 sends the load information of the load 52 to the power supply control device 10, and the acquisition unit 114 acquires the driving current value from the ECU 53 via the I / O 12 (step S205). The process of the acquisition unit 114 acquiring the driving current value from the ECU 53 has been described in Embodiment 2, and the detailed description is omitted. After that, the process enters step S204.

[0149] On the other hand, if the response signal is not received within the predetermined time, the determination unit 116 determines that it is impossible to communicate with the ECU 53 of the load 52 (step S201 : No). In other words, the determination unit 116 determines that the ECU 53 of the load 52 does not exist.

[0150] Next, the determination unit 116 determines whether the first energization occurs between the power supply control device 10 and the load 52 (step S202). If the determination unit 116 determines that the first energization does not occur between the power supply control device 10 and the load 52 (step S202: No), the determination unit 116 waits until the first energization occurs.

[0151] In addition, when the determination unit 116 determines that the above-mentioned initial power-on occurs between the power supply control device 10 and the load 52 (step S202: Yes), the current detection circuit 132 detects the current value of the power-on current I and sends the detected current value of the power-on current I to the acquisition unit 114 of the microcomputer 11, whereby the acquisition unit 114 acquires the current value of the power-on current I at the initial power-on (step S203). The process of the acquisition unit 114 acquiring the current value of the power-on current I at the initial power-on has been described in Embodiment 3, and the detailed description is omitted. Thereafter, the process proceeds to step S204.

[0152] Through the above-described processing, the acquisition unit 114 can acquire the load information (the driving current value or the current value of the energizing current I) of the new load 52 .

[0153] Next, the changing unit 113 changes the electric wire parameter A based on the load information acquired by the acquiring unit 114 and the storage content of the storage unit 11 (step S204). The change of the electric wire parameter A has been described above, and the detailed description is omitted.

[0154] As described above, the power supply control device 10 of Embodiment 4 can change the acquisition source of the load information according to the situation. Therefore, even when communication with the ECU 53 of the load 52 is impossible or the ECU 53 of the load 52 does not exist, the load information can be acquired.

[0155] Since the power supply control device 10 according to the fourth embodiment has the above-described configuration, it also achieves the same effects as those of the first embodiment.

[0156] For the same parts as those in Implementation 1, detailed description is omitted.

[0157] In the above, the case where the wire parameter A is the product of Rw (wire resistance) and Rthw (wire thermal resistance) is described as an example, but the present invention is not limited to this. For example, the wire parameter A may be either Rw or Rthw.

[0158] In addition, the above description is given by taking the case where one load 52 is connected to the power supply control device 10 as an example, but the present invention is not limited thereto, and the same effect is achieved when a plurality of loads 52 are connected to the power supply control device 10. In this case, since the load-side electric wire is determined based on the sum of the driving current values ​​of the plurality of loads 52 connected to the power supply control device 10, the electric wire parameter A can be set by using Rw and Rthw related to the load-side electric wire corresponding to the sum of the driving current values ​​of the plurality of loads 52.

[0159] In addition, although the example using n-channel MOSFET as the switch element 131 is shown above, the present invention is not limited to this. For example, a p-channel MOSFET or a bipolar transistor may be used as the switch element 131.

[0160] In addition, the above example shows the current detection circuit 132 as a sense MOSFET to detect the current value of the conduction current I, but the present invention is not limited to this. For example, the current value of the conduction current I may be detected using a shunt resistor.

[0161] The technical features (constituent elements) described in Embodiments 1 to 4 can be combined with each other, and new technical features can be formed by the combination.

[0162] The embodiments disclosed this time should be considered as illustrative in all aspects and not restrictive. The scope of the present invention is not the above meaning, but is shown by the scope of claims, and is intended to include all changes within the meaning and scope equivalent to the scope of claims.

[0163] The matters described in each embodiment can be combined with each other. In addition, the independent claims and dependent claims described in the scope of protection can be combined with each other in all combinations regardless of the reference form. Moreover, the form of recording a claim that references two or more other claims (multi-dependent claim form) is used in the scope of protection, but it is not limited to this. It is also possible to record it in the form of multiple dependent claims (multi-multi-claim) that record at least one multiple dependent claim.

[0164] Description of symbols

[0165] 10. Power supply control device;

[0166] 11. Microcomputer;

[0167] 12 I / O;

[0168] 13 IPS;

[0169] 20 Power supply;

[0170] 30. Reception Department;

[0171] 40 connectors;

[0172] 50 seats;

[0173] 51 switch;

[0174] 52 load;

[0175] 53 ECU;

[0176] 111 Storage Department;

[0177] 112 Presumption Department;

[0178] 113 Change Department;

[0179] 114 Acquisition Department;

[0180] 115 Instruction Department;

[0181] 116 Judgment Department;

[0182] 131 Switching element;

[0183] 132 current detection circuit;

[0184] A. Wire parameters;

[0185] C. Vehicle;

[0186] I is the current flowing through the device;

[0187] L1, L3 wires;

[0188] L2, L4 communication lines.

Claims

1. A power supply control device is a vehicle power supply control device that controls the power supply to a load based on the estimated result of the temperature of a wire. Among them, The power supply control device includes: A change unit that changes the parameters of the temperature estimation according to the load; and An estimation unit that uses the changed parameters to perform the temperature estimation.

2. The power supply control device according to claim 1, Among them, The power supply control device includes an acquisition unit that acquires specific information related to the parameters, The change unit changes the parameters based on the specific information acquired by the acquisition unit.

3. The power supply control device according to claim 2, Among them, The acquisition unit acquires the specific information from the outside of the vehicle via a reception unit provided in the vehicle.

4. The power supply control device according to claim 2, Among them, The power supply control device includes a storage unit that stores the specific information corresponding to each of a plurality of types of loads that can be connected to this device, The acquisition unit acquires the specific information from a communication unit related to the load, The change unit changes the parameters based on the specific information acquired from the communication unit and the stored content of the storage unit.

5. The power supply control device according to claim 2, Among them, The specific information is at least any one of a current value for driving the load, a current value related to a switch for turning on or off the power supply, and information related to the wire.

6. The power supply control device according to claim 2, Among them, The specific information includes a current value for driving the load, The power supply control device includes: A storage unit that stores the current values of each of a plurality of types of loads that can be connected to this device; and A current detection unit that detects the current value when the device is first powered on with the load, The change unit changes the parameters based on the acquired current value obtained from the current detection unit and the stored content of the storage unit.

7. The power supply control device according to claim 2, Among them, The acquisition unit acquires the specific information via a communication unit related to the load, The specific information includes a current value for driving the load, The power supply control device includes: a current detection unit that detects the current value when the device is first powered on with the load; and a determination unit that determines whether communication with the communication unit is possible, The acquisition unit acquires the specific information from the communication unit or acquires the current value from the current detection unit according to the determination result of the determination unit.

8. The power supply control device according to claim 3, Among them, The acquisition unit acquires the specific information via a communication unit related to the load, When the acquisition unit has acquired the specific information from the reception unit, the specific information acquired from the communication unit is made invalid.

9. The power supply control device according to any one of claims 1 to 8, Among them, The power supply control device includes a semiconductor switch for turning on or off the power supply, The semiconductor switch has a conduction resistance corresponding to the maximum current value among the current values for driving each of a plurality of types of loads that can be connected to this device.

10. A power supply control method is a power supply control method for a vehicle using a power supply control device that controls the power supply to a load based on the estimated result of the temperature of an electric wire. Among them, it includes: changing the parameters of the temperature estimation according to the load; performing the temperature estimation using the changed parameters; and turning on or off the power supply based on the result of the temperature estimation.

11. A computer program is used to control the power supply by using a power supply control device for a vehicle. The power supply control device controls the power supply to a load based on the estimated result of the temperature of an electric wire. Among them, the program causes the computer to execute the following processing: changing the parameters of the temperature estimation according to the load; performing the temperature estimation using the changed parameters; and turning on or off the power supply based on the result of the temperature estimation.

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