JP2016012972A - Current control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a current control device that can prevent overheating of a wire while preventing an erroneous stop of current supply.SOLUTION: A current control device 1 includes IPD (supply units) 31, 32, 33, and 34 that supplies current from an external power supply 4 to loads 51, 52, 53, and 54, and that stop current supply according to the state of current; and performs retry processing for resuming the current supply after IPD 31, 32, 33, and 34 stop the current supply. When the number of retries reaches a predetermined upper limit number of times, the current control device 1 does not perform the retry processing. The restriction on the number of retries prevents an excessive current from continuously flowing through wires 61, 62, 63, and 64 by the retry processing when current supply is stopped due to the excessive current.

Description

  The present invention relates to a current control device that controls a current supplied to a load and prevents overheating of an electric wire through which the current flows.

  Vehicles are provided with various loads that consume power, such as lamps or motors. An electric wire for supplying current from a power source to a load may be damaged due to excessive current flowing when the core wire exposed due to wear comes into contact with the vehicle body and short-circuits. Therefore, it is necessary to protect the electric wires from excessive temperature rise. Patent Document 1 discloses a technique for detecting the occurrence of overcurrent and protecting the electric wire from overheating even when the current value required by the load fluctuates. Patent Document 2 discloses a technique for performing calculation for estimating the temperature of an electric wire based on a current value, and stopping current supply when the temperature is too high.

  Some conventional current control devices use an IPD (Intelligent Power Device) having a self-protection function. The IPD performs self-protection when an excessive current such as an inrush current occurs, or when external noise is superimposed on the current, and stops the current supply. When the IPD self-protection function is activated, the current control device performs a retry process for restarting the current supply after a certain amount of time has elapsed. The retry process prevents erroneous stop of current supply due to noise.

JP2011-166869A JP 2009-130944 A

  The current control device that performs the retry process executes the retry process even when self-protection is performed due to the occurrence of an excessive current. For this reason, if an excessive current continues to be generated, even if the IPD stops supplying the current in response to the generation of the excessive current, the current supply is restarted by the retry process, and the excessive current is However, there is a problem that the electric wire cannot be prevented from overheating.

  The present invention has been made in view of such circumstances, and an object of the present invention is to prevent overheating of an electric wire while preventing erroneous stop of current supply by restricting retry processing. An object of the present invention is to provide a current control device capable of

  A current control device according to the present invention supplies a current from a power supply to a load, stops a current supply according to a current state, and after the supply unit stops a current supply, a current is supplied to the supply unit. In a current control apparatus comprising means for resuming supply, the storage unit stores an upper limit number of times that the supply unit can resume current supply, and counts the number of times the supply unit resumes current supply. The counter includes: a counting unit; and a unit that prohibits the supply unit from resuming current supply when the number of times the counting unit has performed the count reaches the upper limit number.

  The current control device according to the present invention further comprises: a receiving unit that receives a signal instructing current supply; and a unit that causes the supplying unit to start supplying current when the receiving unit receives the signal. And

  The current control device according to the present invention is further characterized by further comprising means for resetting the number of times the counting means has performed counting when the supply section prohibits resumption of current supply.

  In the current control device according to the present invention, the supply unit is configured to stop the current supply when a current value supplied to the load is included in a predetermined range, and the upper limit number of times is the supply unit and When the maximum current within the predetermined range flows through the electric wire used for connection between the loads for the upper limit number of times, the electric wire temperature is predetermined in such a number that the temperature becomes lower than a predetermined temperature. To do.

  In the present invention, the current control device includes a supply unit that supplies a current from an external power source to the load and stops the current supply according to the state of the current, and supplies the current after the supply unit stops the current supply. Let the supply resume. The current control device prevents the current supply from being resumed after the supply unit stops the current supply when the number of times the current supply has been resumed reaches an upper limit number stored in advance. This limits the number of times the supply unit restarts the current supply after stopping the current supply. When the supply unit stops the current supply due to an excessive current, the current supply is restarted to prevent the excessive current from continuing to flow to the electric wires up to the load by limiting the number of times the current supply is restarted.

  In the present invention, the current control device starts current supply to the load when a signal instructing current supply is received from the outside. After the number of times the current supply has been resumed reaches the upper limit number of times, the current controller stops the current supply when the supply unit stops the current supply. Start supplying.

  In the present invention, when the current supply is not resumed after the number of times the current supply is resumed reaches the upper limit number, the number of times the current supply is resumed is reset. When the current supply is started by receiving a signal instructing the current supply, the number of times the current supply is restarted is reset, so that the current control device restarts the current supply after the supply unit stops the current supply. Is possible.

  In the present invention, the supply unit stops the current supply when the current value is included in the predetermined range. The upper limit number of times of resuming the current supply is set to the number of times that the temperature of the electric wire is lower than the predetermined temperature when the maximum current within a predetermined range flows through the electric wire while the current supply is repeatedly stopped and restarted. For this reason, it is prevented that an electric wire overheats by restricting the frequency | count of restarting electric current supply.

  In the present invention, the current control device restarts the current supply when the supply unit stops the current supply to the load, while limiting the number of times the current supply is restarted, To prevent the current from continuing to flow through the wire. Therefore, the present invention has an excellent effect that the electric current control device can prevent the electric wire from being overheated while preventing erroneous stop of the current supply to the load.

It is a block diagram which shows the function structure inside a current control apparatus. It is a timing chart which shows the timing of the electric current supply from a current control apparatus. It is a chart showing an example of the upper limit number of retries stored in the memory. It is a flowchart which shows the example of the procedure of the process which a current control apparatus performs.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
FIG. 1 is a block diagram showing an internal functional configuration of the current control device 1. The current control device 1 is a vehicle-mounted device such as a body ECU (Electronic Control Unit). The current control device 1 is connected to a power supply 4 mounted on the vehicle, and is further connected to loads 51, 52, 53, 54 such as lamps or motors via electric wires 61, 62, 63, 64. The current control device 1 supplies the current from the power source 4 to the loads 51, 52, 53, 54 through the electric wires 61, 62, 63, 64. The current control device 1, the power source 4, the loads 51, 52, 53, and 54, and the electric wires 61, 62, 63, and 64 are mounted on an automobile.

  The current control device 1 includes a control unit 2 and IPDs (Intelligent Power Devices) 31, 32, 33, and 34. The control unit 2 is composed of a microcomputer. The IPDs 31, 32, 33, and 34 correspond to the supply unit in the present invention. The IPDs 31, 32, 33, and 34 are connected to the power source 4 and are connected to loads 51, 52, 53, and 54 via electric wires 61, 62, 63, and 64, respectively. The IPDs 31, 32, 33, and 34 are supplied with current from the power source 4 and supply the supplied current to the loads 51, 52, 53, and 54 through the electric wires 61, 62, 63, and 64. The control unit 2 outputs a control signal for controlling the operation of the IPDs 31, 32, 33, and 34. The IPDs 31, 32, 33, and 34 are supplied with control signals, and control currents supplied to the loads 51, 52, 53, and 54 in accordance with the input control signals. The IPDs 31, 32, 33, and 34 output a current value signal indicating a current value controlled according to the control signal to the control unit 2. The current value signal is, for example, a current signal or a voltage signal proportional to the current value.

  The control unit 2 includes a processing unit 21 that executes processing for current control, an output unit 22, and an A / D converter 23. The processing unit 21 includes a processor and a memory. An output unit 22 and an A / D converter 23 are connected to the processing unit 21. The output unit 22 is connected to each of the IPDs 31, 32, 33, and 34. The processing unit 21 causes the output unit 22 to output a control signal to the IPDs 31, 32, 33, and 34. The A / D converter 23 receives the current value signal output from the IPDs 31, 32, 33, and 34. The A / D converter 23 performs A / D conversion on the input current value signal and inputs it to the processing unit 21. Based on the current value signal input from the A / D converter 23, the processing unit 21 supplies the load 51, 52, 53, 54 from the IPD 31, 32, 33, 34 through the electric wires 61, 62, 63, 64. Determine the current value. Moreover, the process part 21 calculates the temperature of the electric wires 61, 62, 63, 64 based on the determined current value. Specifically, the processing unit 21 determines the temperatures of the electric wires 61, 62, 63, 64 by the method described in Patent Document 1.

  A method for determining the temperature will be briefly described. When n is a natural number, the current value determined at the nth time is I (n), the wire rising temperature during a predetermined time Δt is ΔTw (n), the wire resistance is Rw (n), the wire thermal resistance is Rthw, and when the wire is radiating heat Let τw be a constant. The processing unit 21 calculates the wire rising temperature ΔTw (n) according to the following equation (1).

  The control unit 2 includes a nonvolatile memory (storage unit) 25. Parameters necessary for calculation according to the equation (1) are stored in the memory 25 in advance. As the current value I (n), a value determined based on the current value signals from the IPDs 31, 32, 33, and 34 is used. Moreover, the value measured using the temperature sensor which is not shown in figure in the environment where the electric wires 61, 62, 63, 64 are arrange | positioned, or the predetermined temperature value predetermined is used as an initial value of electric wire temperature. . The processing unit 21 performs a process of determining the temperature of the electric wires 61, 62, 63, 64 based on the initial value of the electric wire temperature and the calculated electric wire rising temperature. In addition, the process part 21 may be a form which determines the temperature of an electric wire by methods other than the calculation using (1) Formula.

  For each of the electric wires 61, 62, 63, 64, an upper limit of the allowable temperature is determined in advance. When the electric wires 61, 62, 63, 64 are overheated and the temperature exceeds the upper limit, the electric wires 61, 62, 63, 64 are damaged, for example, smoke is generated. A predetermined upper limit temperature value is stored in the memory 25 for each of the electric wires 61, 62, 63, 64. Next, the processing unit 21 controls the current so as to suppress the temperature of the electric wires 61, 62, 63, 64 to a predetermined temperature or less based on the determined temperature of the electric wires 61, 62, 63, 64. Generate a signal. For example, the processing unit 21 generates a control signal instructing to continue the current supply to the load when the determined temperature of the specific electric wire is lower than the upper limit temperature of the electric wire, and the determined specific electric wire When the temperature is equal to or higher than the upper limit temperature of the electric wire, a control signal is generated that instructs to stop the current supply to the load. Note that the processing unit 21 may generate a control signal for more complicated feedback control.

  The output unit 22 outputs the control signal generated by the processing unit 21 for each of the electric wires 61, 62, 63, and 64 to the corresponding IPDs 31, 32, 33, and 34. For example, the output unit 22 outputs the control signal generated by the processing unit 21 for the electric wire 61 to the IPD 31. As described above, the IPDs 31, 32, 33, and 34 are supplied with control signals, and supply currents to the loads 51, 52, 53, and 54 through the electric wires 61, 62, 63, and 64 according to the input control signals. To control. In this way, the current control device 1 controls the current and protects the electric wires 61, 62, 63, 64 from excessive temperature rise.

  The current control device 1 is connected to a switch 7 operated by a user. The switch 7 receives an operation from the user and inputs an instruction signal for instructing current supply to the loads 51, 52, 53, 54 to the control unit 2. For example, the switch 7 is an operation switch for operating the loads 51, 52, 53, and 54. The control unit 2 includes a receiving unit 24 that receives an input instruction signal. When the receiving unit 24 receives the instruction signal, the processing unit 21 generates a control signal for supplying current to the loads 51, 52, 53, and 54, and the output unit 22 outputs the control signal to the IPDs 31, 32, 33, The IPD 31, 32, 33, 34 supplies current to the loads 51, 52, 53, 54 according to the control signal.

  Incidentally, the IPDs 31, 32, 33, and 34 have a self-protection function in addition to the function of supplying and stopping current according to the control signal. Specifically, the IPDs 31, 32, 33, and 34 stop supplying current in response to the intrusion of noise from the outside. For example, when noise is superimposed on the current from the power supply 4 and a fluctuation exceeding a predetermined allowable amount occurs, the IPDs 31, 32, 33, and 34 stop supplying current. Further, the IPDs 31, 32, 33, and 34 stop supplying current when an excessive current flows. In the IPDs 31, 32, 33, and 34, a current range in which current supply should be stopped is set in advance. The current included in this current range is an excessive current, and when a current in this current range flows, the IPDs 31, 32, 33, and 34 stop supplying the current. If a current exceeding the current range in which the current supply should be stopped flows, the IPDs 31, 32, 33, and 34 may be damaged. For example, when an excessive inrush current occurs when a current is supplied from the power supply 4, the self-protection of the IPDs 31, 32, 33, and 34 works and the current supply is stopped.

  Based on the current value signals from the IPDs 31, 32, 33, and 34, the control unit 2 detects the stop of the current supply due to the self-protection of the IPDs 31, 32, 33, and 34. The IPDs 31, 32, 33, and 34 may be configured to output a signal indicating that the current supply is stopped by self-protection, separately from the current value signal. The control unit 2 performs a retry process of restarting the current supply after a predetermined time after the current supply by the self-protection of the IPD 31 is stopped. Specifically, the processing unit 21 generates a control signal for causing the IPD 31 to resume current supply, and the output unit 22 outputs the control signal at a timing when a certain time has elapsed since the current supply stopped. The IPD 31 resumes current supply according to the control signal. The value for a certain time is stored in the memory 25. For each of the IPDs 32, 33, and 34, the control unit 2 similarly performs a retry process. Usually, since the occurrence of the inrush current and the noise are temporary, the IPDs 31, 32, 33, and 34 continue the current supply after the current supply is resumed. However, if the state that caused the IPD 31, 32, 33, 34 to stop current supply due to self-protection continues, the IPD 31, 32, 33, 34 again stops current supply due to self-protection, Further, retry processing is performed.

  FIG. 2 is a timing chart showing the timing of current supply from the current control device 1. The horizontal axis in the figure indicates time. The signals in the figure indicate the control signal output from the control unit 2, the current supplied by the IPD 31, and the activation state of the IPD 31 from the top. A high control signal indicates that a control signal instructing the IPD 31 to supply current is being output, and a low indicates that the control signal is not output. A high current supply indicates that the IPD 31 is supplying current to the load 51, and a low current supply indicates that the current supply is stopped. A high self-protection indicates that the self-protection function of the IPD 31 is active, and a low self-protection indicates that the self-protection function is not active.

  While the IPD 31 is continuously supplying current to the load 51, the IPD 31 self-protection is activated for some reason. At this time, the current supply is stopped. The control unit 2 stops outputting the control signal as the current supply is stopped. After a certain time, the control unit 2 outputs again a control signal instructing the IPD 31 to supply current, and the IPD 31 supplies current to the load 31 according to the control signal. If the condition that caused the self-protection of the IPD 31 is continued, the self-protection of the IPD 31 is activated again, and the current supply is stopped. This process is repeated as long as the condition continues. The same processing is performed for each of the IPDs 32, 33, and 34.

  When the excessive current flows, the self-protection function of the IPDs 31, 32, 33, and 34 is activated, and when the excessive current continues, the wires 61, 62, 63, and 64 are excessive when the retry process is performed. Current may flow, and the electric wires 61, 62, 63, 64 may be damaged. Therefore, the current control device 1 determines the upper limit number of times to perform the retry process, and does not perform the retry process after the current supply is stopped when the number of retry processes reaches the upper limit number.

  The upper limit number of retries is predetermined for each of the electric wires 61, 62, 63, 64 and stored in the memory 25. FIG. 3 is a chart showing an example of the upper limit number of retries stored in the memory 25. The channel indicates the channel of the output unit 22, and the upper limit number of retries is stored in association with each channel. Channels 1, 2, 3, and 4 are connected to IPDs 31, 32, 33, and 34, respectively. That is, the upper limit number of retries is stored in the memory 25 for each of the electric wires 61, 62, 63, and 64 through which the IPDs 31, 32, 33, and 34 carry current. In the example shown in FIG. 3, the upper limit number of retries is set to 10 for the electric wire 61, and similarly, the upper limit number of retries is set to 12, 20, and 8 for each of the electric wires 62, 63, and 64. . The upper limit number of retries for each electric wire is determined according to the upper limit of the temperature allowed for each electric wire.

  While the current supply is stopped and the retry process is performed by the IPDs 31, 32, 33, and 34, the maximum currents included in the current range in which the IPDs 31, 32, 33, and 34 should stop the current supply are the electric wires 61, 62, The upper limit number of retries is determined so that the temperature of the electric wires 61, 62, 63, 64 does not exceed the allowable upper limit temperature. Specifically, the wire rising temperature ΔTw (n) is calculated using the equation (1), with the maximum current in the current range in which the IPD 31 should perform self-protection as the current value I (n). The calculation of the wire rising temperature ΔTw (n) is repeated the number of retries, and the number of retries reaching the upper limit temperature at which the temperature of the wire 61 is allowed is obtained. The obtained number of retries is determined as the upper limit number of retries for the electric wire 61. The determined upper limit number is stored in the memory 25. In calculating the wire rising temperature ΔTw (n), the calculation may be performed on the assumption that the current flowing through the wire 61 and the state in which the current does not flow are repeatedly generated the number of retries, The calculation may be performed on the assumption that a current is flowing through the electric wire 61 while the stop of the current supply and the retry process are repeated the number of retries. Similarly, for each of the electric wires 62, 63, 64, the upper limit number of retries is determined and stored in the memory 25. The process of determining the upper limit number of retries is performed when the current control device 1 is designed, and the operation of storing the upper limit number in the memory 25 is performed when the current control device 1 is manufactured.

  FIG. 4 is a flowchart illustrating an example of a procedure of processing executed by the current control device 1. The processing unit 21 stores the number of retries for which retry processing has been performed. The processing unit 21 waits for the receiving unit 24 to receive an instruction signal input from the switch 7 (S1). When the instruction signal is not received (S1: NO), the processing unit 21 continues to wait for the instruction signal. When the receiving unit 24 receives an instruction signal instructing supply of current to the load 51 (S1: YES), the processing unit 21 generates a control signal for causing the IPD 31 to supply current to the load 51, The output unit 22 outputs a control signal to the IPD 31, and the IPD 31 supplies the current from the power source 4 to the load 51 (S2). The IPD 31 outputs a current value signal, the A / D converter 23 A / D converts the current value signal, and the processing unit 21 calculates the current value supplied from the IPD 31 to the load 51 based on the current value signal. Determine (S3). Next, based on the current value, the processing unit 21 determines whether the IPD 31 has stopped current supply due to self-protection (S4).

  When the IPD 31 has not stopped the current supply (S4: NO), the processing unit 21 determines the temperature of the electric wire 61 by calculation using the equation (1), and the determined temperature of the electric wire 61 is a predetermined upper limit temperature. It is determined whether or not this is the case (S5). When the temperature of the electric wire 61 is lower than the predetermined upper limit temperature (S5: NO), the processing unit 21 generates a control signal instructing to continue the current supply to the load 51, and the output unit 22 outputs the control signal. To the IPD 31, and the IPD 31 continues to supply current (S6). Next, the current control device 1 returns the process to S3.

  When the temperature of the electric wire 61 is equal to or higher than the predetermined upper limit temperature (S5: YES), the processing unit 21 generates a control signal instructing to stop the current supply to the load 51, and the output unit 22 controls the control signal. Is output to the IPD 31, and the IPD 31 stops supplying the current to the load 51 (S7). Next, the current control device 1 ends the process.

  In S4, when the processing unit 21 determines that the IPD 31 has stopped current supply due to self-protection (S4: YES), the processing unit 21 determines whether or not the stored number of retries has reached the upper limit number. (S8). When the number of retries is less than the upper limit number (S8: NO), the control unit 2 performs a retry process for causing the IPD 31 to resume current supply after a certain time (S9). In S9, the processing unit 21 generates a control signal for resuming current supply, the output unit 22 outputs a control signal at a timing when a certain time has elapsed after the current supply is stopped, and the IPD 31 Restart supply. Next, the processing unit 21 increments the stored number of retries (S10). The process of S10 corresponds to the counting means. Next, the current control device 1 returns the process to S3.

  When the number of retries has reached the upper limit number (S8: YES), the processing unit 21 generates a control signal instructing to stop the current supply to the load 51, and the output unit 22 sends the control signal to the IPD 31. The IPD 31 stops the current supply to the load 51 (S11). In this way, the current control device 1 prohibits retry processing. Next, the processing unit 21 resets the stored number of retries to zero (S12). Note that the processing unit 21 may reset the number of retries to a value other than zero. Next, the current control device 1 ends the process.

  As shown in FIG. 2, after the last retry process in which the number of retries is equal to the upper limit number, the retry process is not performed even if the IPD 31 stops the current supply due to self-protection. . After the process ends after S7 or S12, no current is supplied to the load 51. When an instruction signal is input from the switch 7 to the current control device 1 by operating the switch 7, the current control device 1 starts processing from S1. Since the number of retries is reset in S12, the retry process can be performed after the process is started by inputting the instruction signal. The current control device 1 executes the same processing for each of the IPDs 32, 33, and 34.

  As described above in detail, in the present embodiment, the current control device 1 supplies current when the current supply to the loads 51, 52, 53, and 54 is stopped by the self-protection of the IPDs 31, 32, 33, and 34. The number of retry processes to be resumed is limited to a predetermined upper limit number or less. When the number of retry processes reaches the upper limit, the retry process is not performed even if the current supply to the loads 51, 52, 53, and 54 is stopped, and the current supply is stopped. Since the upper limit number of retries is determined, when the IPD 31, 32, 33, 34 stops the current supply due to self-protection due to an excessive current, the excessive current is caused by the retry processing. 64 is prevented from continuing to flow. For this reason, the overheating of the electric wires 61, 62, 63, 64 due to the excessive current flowing is prevented. On the other hand, when the self-protection of the IPDs 31, 32, 33, and 34 is activated due to a temporary cause such as generation of noise, the current supply to the loads 51, 52, 53, and 54 is resumed by the retry process. Accordingly, the current control device 1 can prevent overheating of the electric wires 61, 62, 63, 64 while preventing erroneous stop of current supply to the loads 51, 52, 53, 54.

  In the present embodiment, current control device 1 starts current supply when an instruction signal for instructing current supply to loads 51, 52, 53, 54 is input from switch 7. When the current supply to the loads 51, 52, 53, and 54 is stopped after the number of retry processes reaches the upper limit, the current supply continues to be stopped, but the current control device 1 receives the instruction signal. The current supply can be resumed accordingly. In other words, after the retry process is not performed and the current supply to the loads 51, 52, 53, and 54 is stopped, the current supply is not resumed unless an instruction signal is input from the switch 7 by the user's operation.

  Further, in the present embodiment, the current control device 1 is configured such that the retry process is not performed and the current supply to the loads 51, 52, 53, and 54 is stopped after the retry process reaches the upper limit. Reset the number of retries. After the instruction signal is input from the switch 7 and the current supply is resumed, the number of retries is reset, so that the current control device 1 can perform the retry process. In the present embodiment, the upper limit number of retries is such that the IPD 31, 32, 33, 34 performs self-protection while the current supply stoppage and retry process by the IPDs 31, 32, 33, 34 are repeated. It is determined that the temperature of the electric wires 61, 62, 63, 64 does not exceed the allowable upper limit temperature, assuming that the maximum current in the current range to be performed flows. For this reason, limiting the number of times of retry processing prevents the temperature of the wires 61, 62, 63, 64 from exceeding the upper limit temperature and damaging the wires 61, 62, 63, 64.

  In the present embodiment, the control unit 2 determines whether or not to stop the current supply. However, the current control device 1 controls whether or not to stop the current supply. The configuration may be such that the IPD 31, 32, 33, 34 does not perform in the unit 2. Further, in the present embodiment, a mode in which current is supplied to four loads using the current control device 1 is shown, but the current control device 1 is a mode in which current is supplied to other numbers of loads. Also good. Moreover, in this Embodiment, although the supply part in this invention comprised IPD31,32,33,34, and the control part 2 was comprised with the microcomputer, the electric current control apparatus 1 is restricted to this. Instead, the supply unit and the control unit 2 may be configured by other devices. In the present embodiment, the current control device 1 receives a signal from the switch 7 operated by the user. However, the current control device 1 is a signal for instructing current supply from a device other than the switch 7. May be accepted. In addition, the current control device 1 may be a device other than the vehicle-mounted device as long as it controls the current supplied to the load.

DESCRIPTION OF SYMBOLS 1 Current control apparatus 2 Control part 21 Processing part 22 Output part 23 A / D converter 24 Reception part 25 Memory (memory | storage part)
31, 32, 33, 34 IPD (supply unit)
4 Power supply 51, 52, 53, 54 Load 61, 62, 63, 64 Electric wire 7 Switch

Claims (4)

A current unit comprising: a supply unit that supplies current from a power source to a load, and stops current supply according to a current state; and a unit that causes the supply unit to resume current supply after the supply unit stops supplying current. In the control device,
A storage unit storing an upper limit number of times that the supply unit can resume current supply;
Counting means for counting the number of times the supply unit has restarted current supply;
A current control device comprising: means for prohibiting the supply unit from resuming current supply when the number of times the counting means performs the count reaches the upper limit number. A reception unit for receiving a signal instructing current supply;
The current control device according to claim 1, further comprising: means for causing the supply unit to start supplying current when the reception unit receives the signal. The current control device according to claim 2, further comprising a unit that resets the number of times the counting unit performs counting when the supply unit prohibits resumption of current supply. The supply unit is configured to stop current supply when a current value supplied to a load is included in a predetermined range;
The upper limit number of times is such that when the maximum current in the predetermined range flows in the electric wire used for connection between the supply unit and the load, the temperature of the electric wire becomes lower than a predetermined temperature when the upper limit number of times flows. The current control device according to any one of claims 1 to 3, wherein the current control device is predetermined.

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