Power source control device

Abstract

To suppress influence by a momentary interruption of power supply in a load of a second system when rewriting processing of a control program is performed.SOLUTION: A power source control device according to one aspect of an embodiment comprises an inter-system switch, a bypass switch, a controller, and a power supply mechanism. The inter-system switch is a normally open type switch provided on an inter-system line that connects a first system and a second system. The bypass switch is a normally close type switch connected in parallel with the inter-system switch. The controller outputs a control signal for controlling the inter-system switch and the bypass switch in accordance with a control program, and is reset when rewriting processing of the control program is performed. When the rewriting processing of the control program is performed in the controller, the power supply mechanism supplies power to a second load during a period in which both the inter-system switch and the bypass switch are turned off due to output stoppage of the control signal caused by resetting.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a power supply control device. [Background technology]

[0002] Conventionally, a power supply system has been known that includes an inter-system switch that connects a first system and a second system, and a bypass switch that is connected in parallel to the inter-system switch (see, for example, Patent Document 1). In such a power supply system, during normal operation with a vehicle ignition (hereinafter referred to as "IG") on, a control signal is output that turns the inter-system switch on and the bypass switch off, thereby supplying power from the power supply of the first system to the load of the second system via the inter-system switch. Furthermore, when the power supply system detects that the IG is off, it stops outputting the control signal and enters a normally state where the inter-system switch is off and the bypass switch is on, thereby supplying power from the power supply of the first system to the load of the second system via the bypass switch while the IG is off.

[0003] In the conventional technology, when the IG changes from on to off, the inter-system switch changes from on to off and the bypass switch changes from off to on, but the switching timing of the control signal is controlled so that there is no period in which both switches are off during the termination sequence, etc. In other words, if there is a period in which both switches are off, the power supply to the load of the second system is momentarily interrupted, which is a so-called momentary blackout, and therefore the switching timing of the control signal is controlled as described above. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-111637 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional technology, when the control program that controls the inter-system switch and the bypass switch is rewritten (reprogrammed), there is a possibility that the power supply to the load of the second system may be momentarily interrupted.

[0006] Specifically, when the control program is rewritten, the controller is reset. As a result, the control program does not execute its termination sequence, and control signals to both switches are interrupted. Therefore, if the time it takes for the two switches to transition to their normal state differs due to individual differences, there is a possibility that both switches will be off for a period of time, resulting in a momentary interruption of power supply to the load in the second system. This could result in the impact of a momentary interruption, such as an abnormal operation of the load in the second system, or the load in the second system detecting the momentary interruption and storing it as diagnostic information, which would otherwise be unnecessary.

[0007] The present invention has been made in consideration of the above, and aims to provide a power supply control device that can suppress the effects of momentary interruptions in power supply to loads in the second system when a control program rewrite process is performed. [Means for solving the problem]

[0008] In order to solve the above problems and achieve the object, in the present invention, a power supply control device includes an inter-system switch, a bypass switch, a controller, and a power supply mechanism. The inter-system switch is a normally open switch provided on an inter-system line connecting a first system that supplies power from a first power source to a first load and a second system that supplies power from a second power source to a second load. The bypass switch is a normally closed switch connected in parallel to the inter-system switch. The controller outputs control signals that control the inter-system switch and the bypass switch according to a control program, and is reset when a rewrite process of the control program is performed. When the rewrite process of the control program is performed in the controller, the power supply mechanism supplies power to the second load during a period in which the inter-system switch and the bypass switch are both turned off due to the resetting that stops the output of the control signal.

[0009] Also, in the present invention, a power supply control device includes an inter-system switch, a bypass switch, and a controller. The inter-system switch is a normally open switch provided on an inter-system line connecting a first system that supplies power from a first power source to a first load and a second system that supplies power from a second power source to a second load. The bypass switch is a normally open switch connected in parallel to the inter-system switch. The controller outputs a control signal that controls the inter-system switch and the bypass switch according to a control program, and is reset when a rewrite process of the control program is performed. Furthermore, the controller notifies the controller that there is a possibility of a momentary interruption in the power supply to the second load when the rewrite process of the control program is performed. [Effects of the Invention]

[0010] According to the present invention, since the power supply mechanism that supplies power to the second load is provided during the period when both the inter-system switch and the bypass switch are turned off due to the stop of output of the control signal by resetting, it is possible to prevent a momentary interruption in the power supply to the second load, thereby suppressing the influence of a momentary interruption in the power supply on the second load.

[0011] Furthermore, according to the present invention, when the control program is rewritten, the second load is notified that there is a possibility of a momentary interruption in the power supply to the second load, and the second load can recognize that the momentary interruption is not due to an abnormality. Therefore, the second load can be prevented from performing a momentary interruption response process, thereby suppressing the impact of the momentary interruption in the power supply to the second load. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is an explanatory diagram showing an example of the configuration and operation of a power supply system including a power supply control device according to a first embodiment. [Figure 2] FIG. 2 is an explanatory diagram showing an example of the configuration and operation of a power supply system including a power supply control device according to the first embodiment. [Figure 3] FIG. 3 is an explanatory diagram showing an example of the configuration and operation of a power supply system including a power supply control device according to the first embodiment. [Figure 4] FIG. 4 is a block diagram showing an example of the configuration of a microcomputer. [Figure 5] FIG. 5 is a time chart showing an example of the operation of the inter-system switch and the bypass switch. [Figure 6] FIG. 6 is an explanatory diagram showing an example of the operation of the power supply system. [Figure 7] FIG. 7 is a time chart showing an example of the operation of the inter-system switch and the bypass switch. [Figure 8] FIG. 8 is a flowchart showing an example of processing executed by the controller of the power supply control device according to the first embodiment. [Figure 9]FIG. 9 is an explanatory diagram showing an example of the configuration and operation of a power supply system including a power supply control device according to the second embodiment. [Figure 10] FIG. 10 is a time chart showing an example of the operation of the inter-system switch, the bypass switch, and the battery switch. [Figure 11] FIG. 11 is a diagram showing an example of a processing sequence executed by a power supply system including a power supply control device according to the second embodiment. [Figure 12] FIG. 12 is an explanatory diagram showing an example of the configuration and operation of a power supply system including a power supply control device according to the third embodiment. [Figure 13] FIG. 13 is a time chart showing an example of the operation of the inter-system switch, the bypass switch, the pulse output device, and the battery switch. [Figure 14] FIG. 14 is a flowchart showing an example of processing executed by the controller of the power supply control device according to the third embodiment. [Figure 15] FIG. 15 is an explanatory diagram showing an example of the configuration and operation of a power supply system including a power supply control device according to the fourth embodiment. [Figure 16] FIG. 16 is a time chart showing an example of the operation of the inter-system switch, the bypass switch, the latch circuit, and the battery switch. [Figure 17] FIG. 17 is a flowchart showing an example of processing executed by the controller of the power supply control device according to the fourth embodiment. [Figure 18] FIG. 18 is an explanatory diagram showing an example of the configuration and operation of a power supply system including a power supply control device according to a modification of the fourth embodiment. [Figure 19] FIG. 19 is a flowchart illustrating an example of processing executed by a controller of a power supply control device according to a modification of the fourth embodiment. [Figure 20] FIG. 20 is an explanatory diagram showing an example of the configuration and operation of a power supply system including a power supply control device according to the fifth embodiment. [Figure 21] FIG. 21 is a diagram showing an example of a processing sequence executed by a power supply system including a power supply control device according to the fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of a power supply control device will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiment described below. The power supply control device according to the embodiment is mounted on a vehicle such as an electric vehicle, a hybrid vehicle, or an internal combustion engine vehicle, but is not limited thereto.

[0014] [First embodiment] 1 to 3 are explanatory diagrams showing an example of the configuration and operation of a power supply system including a power supply control device according to Embodiment 1. Fig. 1 shows the power supply system in a state where the ignition (IG) of a vehicle is on.

[0015] As shown in FIG. 1, the power supply system 1 includes a first power supply 10, a first load 101, a second load 102, a power supply control device 30, and an external device 200.

[0016] The first power source 10 is, for example, a lead battery. The first power source 10 may be any secondary battery other than a lead battery. The first power source 10 is a main power source. The first power source 10 is connected to the first load 101 via a first system (primary system) 110 that supplies the power of the first power source 10 to the first load 101. Although not shown, the first power source 10 is charged by a generator or a DC-DC converter. For example, in the case of an engine vehicle, the generator charges the first power source 10 using an alternator that converts the rotational force of the engine into electric power to generate electricity. In addition, in the case of a vehicle equipped with a high-voltage battery, such as an electric vehicle, the first power source 10 is charged by a DC-DC converter that reduces the voltage of the high-voltage battery or the voltage of a generator that converts regenerative energy of the vehicle into electric power to generate electricity.

[0017] The first load 101 includes a load that receives power when the IG is on and does not require power when the IG is off. The first load 101 includes, but is not limited to, driving loads required for driving the vehicle, such as an electric brake device, an electric accelerator device, and an electric steering device, as well as on-board devices (general loads) such as a display and an air conditioner.

[0018] The second load 102 includes an electrical load to which power is supplied when the ignition is on and when the ignition is off. The second load 102 includes, for example, a driving load, a clock function unit of an on-board device, an immobilizer, and other loads, but is not limited to these. The clock function unit of the on-board device and the immobilizer are examples of loads that operate while the vehicle is stopped with the ignition off. The second load 102 also includes a load (driving load, a radar device that detects objects around the vehicle, etc.) that causes the vehicle to run to safety when power to the first system 110 fails, as will be described later.

[0019] The power supply control device 30 is connected between the first power supply 10 and the first and second loads 101, 102. The power supply control device 30 controls the power supply to the first and second loads 101, 102. The power supply control device 30 includes a microcomputer 50, a second power supply 20, an inter-system switch 41, a bypass switch 42, a battery switch 43, and voltage sensors 91, 92.

[0020] The microcomputer 50 performs various processes, such as controlling the inter-system switch 41, the bypass switch 42, and the battery switch 43. Specifically, the microcomputer 50 is connected to the bypass switch 42 via a control line 60 that controls the bypass switch 42. The microcomputer 50 is connected to the inter-system switch 41 via a control line 70 that controls the inter-system switch 41. The microcomputer 50 is connected to the inter-system switch 41 via a control line 80 that controls the battery switch 43. The microcomputer 50 outputs control signals to control the corresponding switches through the control lines 60, 70, and 80. The detailed configuration of the microcomputer 50 will be described later using FIG. 4. A power supply mechanism 31a is also provided on the control line 70, which will also be described later.

[0021] The second power source 20 is, for example, a lithium ion battery. The second power source 20 may be any secondary battery other than a lithium ion battery. The second power source 20 can function as a backup power source in the event that the first power source 10 is unable to supply power. The second power source 20 is connected to the second load 102 via a second system (secondary system) 120 that supplies power from the second power source 20 to the second load 102. The second power source 20 is charged by the above-mentioned generator or the like.

[0022] The inter-system switch 41 is provided between the first system 110 and the second system 120. Specifically, the inter-system switch 41 is provided on the inter-system line 130 that connects the first system 110 and the second system 120. The inter-system switch 41 is a normally open switch. Therefore, the inter-system switch 41 turns on in response to a control signal output from the microcomputer 50, and electrically connects the first system 110 and the second system 120. On the other hand, when the output of the control signal from the microcomputer 50 stops, the inter-system switch 41 enters a normally open state and turns off.

[0023] The bypass switch 42 is connected in parallel to the inter-system switch 41. The bypass switch 42 is a normally closed switch. Therefore, the bypass switch 42 is turned off in response to a control signal output from the microcomputer 50. On the other hand, when the output of the control signal from the microcomputer 50 stops, the bypass switch 42 enters a normally closed state and is turned on, electrically connecting the first system 110 and the second system 120.

[0024] More specifically, during normal operation with the IG on, as shown in Fig. 1, a control signal is output from the microcomputer 50, which turns on the inter-system switch 41 and turns off the bypass switch 42. As a result, power from the first power source 10 is supplied to the first load 101, as indicated by the dashed arrows, and is also supplied to the second load 102 via the inter-system switch 41. Fig. 2 shows the power supply system 1 in the IG off state of the vehicle. As shown in Fig. 2, when the IG is off, the output of the control signal from the microcomputer 50 is stopped, the inter-system switch 41 is turned off, and the bypass switch 42 is turned on. As a result, power from the first power source 10 is supplied to the second load 102 via the bypass switch 42.

[0025] The battery switch 43 is provided between the second power source 20 and the second system 120. The battery switch 43 is a switch that connects the second power source 20 to the second system 120. The voltage sensor 91 detects the voltage of the first system 110 and outputs the detection result to the microcomputer 50. The voltage sensor 92 detects the voltage of the second system 120 and outputs the detection result to the microcomputer 50.

[0026] The microcomputer 50 monitors the input voltages of the first system 110 and the second system 120, and can detect the occurrence of a power supply failure. FIG. 3 shows the power supply system 1 in a state where a power supply failure has occurred in the first system 110. As shown in FIG. 3, if a power supply failure such as a ground fault 300 occurs in the first system 110, power cannot be supplied from the first power source 10. In such a case, the microcomputer 50 turns off the inter-system switch 41 and the bypass switch 42 and turns on the battery switch 43. This allows the power supply system 1 to supply power from the second power source 20 to the second load 102 via the second system 120, allowing the vehicle to run for evacuation by the second load 102.

[0027] The external device 200 is communicably connected to the microcomputer 50 via a wired or wireless connection. The external device 200 may be a terminal device such as a personal computer (PC), or a server device installed remotely from the vehicle, but is not limited to these.

[0028] The external device 200 is a device that controls the rewriting process of the control program 52a (see FIG. 4) stored in the microcomputer 50. In other words, the external device 200 is a device that manages the rewriting process.

[0029] The configuration of the microcomputer 50 will now be described with reference to Fig. 4. Fig. 4 is a block diagram showing an example of the configuration of the microcomputer 50.

[0030] 4, the microcomputer 50 includes a controller (controller) 51 and a storage unit 52. The controller 51 is realized by, for example, a central processing unit (CPU) or a micro processing unit (MPU) executing various programs stored in the storage unit 52 using a random access memory (RAM) as a working area. The controller 51 can also be realized by, for example, an integrated circuit such as an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA).

[0031] The storage unit 52 is realized by, for example, a semiconductor memory element such as a RAM or a flash memory, or a storage device such as a hard disk or an optical disk. In the example of Fig. 4, the storage unit 52 stores a control program 52a, a rewriting program 52b, various programs, and the like.

[0032] The control program 52a is a program used to control the inter-system switch 41, the bypass switch 42, and the battery switch 43. That is, the controller 51 executes the control program 52a to control the inter-system switch 41, the bypass switch 42, and the battery switch 43. In other words, the controller 51 outputs control signals to control the inter-system switch 41, the bypass switch 42, the battery switch 43, etc. in accordance with the control program 52a.

[0033] The control program 52a may need to be rewritten (updated) when, for example, a function is added, or when a defect is discovered after the fact, etc. The rewriting program 52b is a program used for the rewriting process.

[0034] Specifically, when a rewrite process is required, the external device 200 (see FIG. 1) transmits to the controller 51 a request to execute the rewrite process of the control program 52a and update data to be used in the rewrite process. When the controller 51 receives the request to execute the rewrite process, it is reset. In other words, the controller 51 is reset when the rewrite process of the control program 52a is executed. After being reset, the controller 51 executes the rewrite program 52b, thereby applying the update data to the control program 52a and rewriting the control program 52a. Next, the controller 51 executes the control program 52a after the rewrite process, thereby controlling the system switch 41 and the like.

[0035] An example of the operation of the inter-system switch 41 and the bypass switch 42 during the rewrite process of the control program 52a will now be described with reference to Fig. 5. Fig. 5 is a time chart showing an example of the operation of the inter-system switch 41 and the bypass switch 42 during the rewrite process of the control program 52a. Note that hereinafter, the rewrite process may be referred to as "repro (reprogramming)."

[0036] 5, the controller 51 executes a control program 52a from time T0 to time T11 before re-programming is executed (requested), thereby controlling the inter-system switch 41 and the bypass switch 42. Specifically, the controller 51 outputs a control signal to the inter-system switch 41 to turn it on, and outputs a control signal to the bypass switch 42 to turn it off. As a result, the power of the first power source 10 is supplied to the second load 102 via the inter-system switch 41 (see FIG. 1).

[0037] When the controller 51 receives a request to execute reprogramming from the external device 200 at time T11, the controller 51 is reset at time T12. The reset controller 51 does not execute the termination sequence in the control program 52a, and therefore control signals to the inter-system switch 41 and the bypass switch 42 are discontinued. At this time, depending on individual differences between the switches 41 and 42, the timing at which the bypass switch 42 turns on and enters the normal state (see time T13) may be delayed by a period Ta from the timing at which the inter-system switch 41 turns off and enters the normal state (see time T12). During this period Ta, both the switches 41 and 42 are off, which may cause a momentary interruption in the power supply to the second load 102.

[0038] Therefore, the power supply control device 30 according to this embodiment is provided with a power supply mechanism 31a as shown in Fig. 1. The power supply mechanism 31a is a mechanism that supplies power to the second load 102 during a period in which the inter-system switch 41 and the bypass switch 42 are both turned off due to the output of the control signal being stopped by a reset (period Ta in Fig. 5).

[0039] Specifically, the power supply mechanism 31a is provided on a control line 70 that controls the inter-system switch 41. The power supply mechanism 31a includes a delay circuit 71, a first switch 72a, and a second switch 72b. The control line 70 includes a first control line 70a and a second control line 70b. The first control line 70a and the second control line 70b are control lines that branch off from the control line 70 at a connection point p1 and connect at a connection point p2.

[0040] The first control line 70a is provided with a first switch 72a. The second control line 70b is provided with a delay circuit 71 and a second switch 72b. In other words, the first switch 72a is connected in parallel with the delay circuit 71 and the second switch 72b. In addition, the second control line 70b is connected in series with the delay circuit 71 and the second switch 72b. In this way, the first control line 70a is a control line that does not have a delay circuit 71, and the second control line 70b is a control line that has a delay circuit 71.

[0041] The delay circuit 71 includes a capacitor 71a and a resistor 71b. The capacitor 71a is provided between the resistor 71b and the second switch 72b. The resistor 71b is provided between the microcomputer 50 and the capacitor 71a.

[0042] In the power supply mechanism 31a configured as described above, the controller 51 enables the first control line 70a during normal operation and enables the second control line 70b when reprogramming the control program 52a. Note that this normal operation includes times other than when reprogramming is performed, in other words, it includes times when reprogramming is not performed.

[0043] Specifically, during normal operation, the controller 51 turns on the first switch 72a and turns off the second switch 72b, thereby enabling the first control line 70a and disabling the second control line 70b (see FIG. 1). As a result, when reproducibility is not being achieved, the controller 51 can output power indicating the control signal to the inter-system switch 41 via the first control line 70a without any response delay, thereby controlling the inter-system switch 41.

[0044] FIG. 6 is an explanatory diagram showing an example of the operation of the power supply system 1 during reprogramming. As shown in FIG. 6, when reprogramming the control program 52a, the controller 51 disables the first control line 70a and enables the second control line 70b by turning off the first switch 72a and turning on the second switch 72b. When the second switch 72b is turned on and the second control line 70b is enabled, the capacitor 71a outputs the stored power as a control signal to the inter-system switch 41. This turns on the inter-system switch 41, and power from the first power supply 10 is supplied to the second load 102 via the inter-system switch 41. The resistor 71b is a resistor for preventing power from being supplied from the capacitor 71a to the microcomputer 50.

[0045] The operation of the power supply system 1 during the above-described reprogramming will be described in detail with reference to Fig. 7. Fig. 7 is a time chart showing an example of the operation of the inter-system switch 41 and the bypass switch 42 during the reprogramming process (reprogramming) of the control program 52a. In Fig. 7, the time T0 to T11 before the reprogramming is executed (requested) is during normal operation, and the first control line 70a is enabled and the second control line 70b is disabled.

[0046] 7, when the controller 51 receives a request to execute repro from the external device 200 at time T11, the controller 51 disables the first control line 70a and enables the second control line 70b at time T11a before resetting. Then, the controller 51 resets with the second control line 70b enabled (see time T12).

[0047] At this time, the control signal output from the reset controller 51 to the inter-system switch 41 stops, but because the second control line 70b is enabled, power from the capacitor 71a is output to the inter-system switch 41 as a control signal. Therefore, the inter-system switch 41 continues to be in the ON state. More specifically, even after the controller 51 is reset at time T12, the inter-system switch 41 continues to be in the ON state due to power from the capacitor 71a. When the power from the capacitor 71a decreases at time T14 and the output of the control signal stops, the inter-system switch 41 turns off.

[0048] That is, the delay circuit 71 including the capacitor 71a delays the stop of the output of the control signal from the inter-system switch 41 due to resetting for a certain time. In the example of FIG. 7, the certain time is a period Tb from time T12 when the controller 51 is reset to time T14 when the power of the capacitor 71a drops and the output of the control signal is stopped. Therefore, the period Tb can also be called a delay period. For ease of understanding, in FIG. 7, a dashed line indicates a state in which the control signal output from the reset controller 51 to the inter-system switch 41 is stopped and the inter-system switch 41 is turned off in a case where the delay circuit 71 is not provided.

[0049] The power stored in the capacitor 71a is set to a value that allows the on state of the inter-system switch 41 to continue for a period Tc longer than the time T13 at which the output of the control signal for the bypass switch 42 is stopped by a reset and the bypass switch 42 is turned on. Note that the power stored in the capacitor 71a is not limited to the above, and may be set to a value that allows the on state of the inter-system switch 41 to continue for a long time, for example, until the same time as the time T13 at which the bypass switch 42 is turned on.

[0050] In this way, by including the power supply mechanism 31a, the power supply control device 30 can eliminate the period (see period Ta in FIG. 5 ) during which both the inter-system switch 41 and the bypass switch 42 are turned off when the controller 51 is reset to perform reprogramming. This makes it possible to prevent a momentary interruption in the power supply to the second load 102, thereby suppressing the effects of a momentary interruption in the power supply to the second load 102.

[0051] Next, processing executed by the controller 51 of the power supply control device 30 according to the first embodiment will be described with reference to Fig. 8. Fig. 8 is a flowchart showing an example of processing executed by the controller 51 of the power supply control device 30 according to the first embodiment. This processing is executed repeatedly while the power supply control device 30 is running.

[0052] As shown in FIG. 8, the controller 51 determines whether a re-programming request has been received from the external device 200 (step S101). If the controller 51 determines that a re-programming request has not been received (step S101, No), that is, during normal operation, the controller 51 enables the first control line 70a (step S102). Specifically, the controller 51 enables the first control line 70a by turning on the first switch 72a. At this time, the controller 51 disables the second control line 70b by turning off the second switch 72b. As a result, during normal operation when re-programming is not being performed, the controller 51 outputs power indicating the control signal to the inter-system switch 41 via the first control line 70a, and controls the inter-system switch 41 with good responsiveness without being affected by the delay circuit 71.

[0053] On the other hand, if it is determined that a request to execute repro has been received (Yes in step S101), the controller 51 enables the second control line 70b (step S103). Specifically, the controller 51 enables the second control line 70b by turning on the second switch 72b. At this time, the controller 51 disables the first control line 70a by turning off the first switch 72a.

[0054] Next, the controller 51 executes a reset process (step S104). At this time, the control signal output from the controller 51 to the inter-system switch 41 is stopped, but because the second control line 70b is enabled, power from the capacitor 71a is output as a control signal to the inter-system switch 41. Therefore, the inter-system switch 41 continues to be in the on state, and therefore the power of the first power source 10 is supplied to the second load 102 via the inter-system switch 41 (see FIG. 6).

[0055] Next, the controller 51 executes rewriting (rewriting process) of the control program 52a (step S105). Specifically, the controller 51 executes the rewriting program 52b to rewrite the control program 52a. Then, when the rewriting is completed, the controller 51 ends the current process.

[0056] As described above, the power supply control device 30 according to the first embodiment includes the inter-system switch 41, the bypass switch 42, the controller 51, and the power supply mechanism 31a. The inter-system switch 41 is a normally open switch provided on the inter-system line 130 connecting the first system 110, which supplies power from the first power source 10 to the first load 101, and the second system 120, which supplies power from the second power source 20 to the second load 102. The bypass switch 42 is a normally closed switch connected in parallel to the inter-system switch 41. The controller 51 outputs control signals for controlling the inter-system switch 41 and the bypass switch 42 in accordance with a control program 52a and is reset when the control program 52a is rewritten. When the control program 52a is rewritten in the controller 51, the power supply mechanism 31a supplies power to the second load 102 during a period in which both the inter-system switch 41 and the bypass switch 42 are turned off due to the stop of output of the control signal caused by the reset. As described above, the power supply control device 30 according to the first embodiment is provided with the power supply mechanism 31a, and therefore it is possible to eliminate the period during which both the inter-system switch 41 and the bypass switch 42 are turned off, and to prevent a momentary interruption in the power supply to the second load 102. This makes it possible to suppress the effects of a momentary interruption in the power supply to the second load 102. Specifically, it is possible to suppress the effects of a momentary interruption, such as an abnormality occurring in the operation of the second load 102 due to the momentary interruption, or the second load 102 detecting the momentary interruption and storing it as diagnostic information, thereby performing unnecessary processing to deal with the momentary interruption.

[0057] The power supply mechanism 31a also includes a delay circuit 71 that is provided on a control line 70 that controls the inter-system switch 41 and that delays, for a certain period of time, the cessation of the output of the control signal due to resetting. This allows the inter-system switch 41 to continue to be in the on state due to the delay circuit 71, even after the output of the control signal from the controller 51 is halted due to resetting. Therefore, power from the first power source 10 is supplied to the second load 102 via the inter-system switch 41. In other words, the delay circuit 71 can eliminate the period during which both the inter-system switch 41 and the bypass switch 42 are off, thereby reliably preventing a momentary interruption in the power supply to the second load 102.

[0058] The controller 51 enables the first control line 70a, which does not have the delay circuit 71, during normal operation, and enables the second control line 70b, which has the delay circuit 71, when performing a rewrite process (reprogramming) of the control program 52a. By switching the control lines to be enabled between normal operation and reprogramming in this way, it is possible to prevent the delay circuit 71 from affecting the control of the inter-system switch 41 during normal operation, for example.

[0059] [Second embodiment] Next, a power supply control device 30 according to a second embodiment will be described with reference to Fig. 9. Fig. 9 is an explanatory diagram showing an example of the configuration and operation of a power supply system 1 including a power supply control device 30 according to the second embodiment. Note that, in the following, components common to the first embodiment will be assigned the same reference numerals and descriptions thereof will be omitted.

[0060] 9, the power supply control device 30 according to the second embodiment does not include the power supply mechanism 31a according to the first embodiment. The power supply control device 30 according to the second embodiment is configured so that the battery switch 43 functions as the power supply mechanism 31b. In other words, the power supply mechanism 31b includes the battery switch 43.

[0061] The battery switch 43 is connected to the external device 200 via a control line 81 that controls the battery switch 43. That is, the battery switch 43 is connected to the microcomputer 50 via the control line 80, and is also connected to the external device 200 via the control line 81.

[0062] In the second embodiment, when the control program 52a is reprogrammed, the external device 200 outputs a drive signal for the battery switch 43 to the battery switch 43 via the control line 81 to turn on (make conductive) the battery switch 43. As a result, power from the second power source 20 is supplied to the second load 102 via the battery switch 43. More specifically, even if a period occurs in which both the inter-system switch 41 and the bypass switch 42 are turned off due to the output of the control signal being stopped by a reset, power can be supplied from the second power source 20 to the second load 102 by making the battery switch 43 conductive.

[0063] The operation of the power supply system 1 during the above-described repro will be described in detail with reference to Fig. 10. Fig. 10 is a time chart showing an example of the operation of the inter-system switch 41, the bypass switch 42, and the battery switch 43 during the rewrite process (repro) of the control program 52a.

[0064] As shown in FIG. 10, at time T21, the external device 200 transmits a request to execute re-processing to the controller 51, and the controller 51 accepts the transmitted request to execute re-processing.

[0065] At time T22, after transmitting a request to execute repro to the controller 51 and before the controller 51 performs a reset, the external device 200 outputs a drive signal for the battery switch 43 to the battery switch 43. This turns on the battery switch 43 and makes it conductive. Then, with the battery switch 43 in the on state, the controller 51 performs a reset (see time T23).

[0066] At this time, the control signal output from the reset controller 51 to the inter-system switch 41 stops, so that, for example, the inter-system switch 41 may be turned off at time T23 and the bypass switch 42 may be turned on at time T24. In such a case, the inter-system switch 41 and the bypass switch 42 are both turned off during the period Ta from time T23 to time T24. However, because the battery switch 43 is turned on and conducting, power is supplied from the second power source 20 to the second load 102. In other words, it is possible to prevent a momentary interruption in the power supply to the second load 102.

[0067] Then, at time T25, the battery switch 43 is turned off by the rewriting program 52b used in the rewriting process. More specifically, the controller 51 executes the rewriting program 52b to output an OFF signal that turns off the battery switch 43, thereby turning off the battery switch 43.

[0068] As described above, in the second embodiment, when reprogramming is performed, the battery switch 43 is turned on for a certain period of time, thereby supplying power from the second power supply 20 to the second load 102. In the example of Fig. 10, the certain period of time is the period Td from time T22 when the battery switch 43 is turned on by the external device 200 to time T25 when the battery switch 43 is turned off by the rewriting program 52b.

[0069] The period Td includes the period Ta during which both the inter-system switch 41 and the bypass switch 42 are turned off by the reset, and is set to be longer than the period Ta, but is not limited to this. That is, the period Td may be the same as the period Ta during which both the inter-system switch 41 and the bypass switch 42 are turned off, for example.

[0070] Next, processing executed by the power supply system 1 according to the second embodiment will be described with reference to Fig. 11. Fig. 11 is a diagram showing an example of a processing sequence executed by the power supply system 1 including the power supply control device 30 according to the second embodiment.

[0071] 11, the external device 200 outputs a request to the controller 51 to execute repro (step S201). The external device 200 also outputs a drive signal for the battery switch 43 to the battery switch 43 (step S202). This turns on the battery switch 43 and makes it conductive (step S203). In this way, when the battery switch 43 is conductive, power is supplied from the second power source 20 to the second load 102.

[0072] When the controller 51 receives a request to execute reprinting from the external device 200, it executes a reset process (step S204). At this time, the control signals output from the controller 51 to the inter-system switch 41 and the bypass switch 42 are stopped. Therefore, both the inter-system switch 41 and the bypass switch 42 may be turned off, but because the battery switch 43 is turned on and conducting, power is supplied to the second load 102 from the second power source 20 (see FIG. 9).

[0073] Next, the controller 51 executes rewriting (rewriting process) of the control program 52a (step S205). Specifically, the controller 51 executes the rewriting program 52b to rewrite the control program 52a. Furthermore, by executing the rewriting program 52b, the controller 51 outputs an OFF signal to the battery switch 43 to turn off the battery switch 43 (step S206). As a result, the battery switch 43 is turned off (step S207).

[0074] In the above description, the rewriting program 52b turns off the battery switch 43. However, the present invention is not limited to this. For example, the external device 200 may turn off the battery switch 43.

[0075] As described above, in the second embodiment, the power supply mechanism 31b is configured to include the battery switch 43. In the second embodiment, when the controller 51 reprograms the control program 52a, the battery switch 43 is turned on for a certain period of time, thereby supplying power from the second power source 20 to the second load 102. As a result, even if a period Ta occurs during which both the inter-system switch 41 and the bypass switch 42 are turned off due to the stop of output of the control signal caused by a reset, power is supplied from the second power source 20 to the second load 102. Therefore, it is possible to prevent a momentary interruption in the power supply to the second load 102, and as a result, it is possible to suppress the influence of a momentary interruption in the power supply on the second load 102.

[0076] Furthermore, the battery switch 43 is turned on and made conductive by the external device 200 that controls the rewriting process (repro). As a result, even if the controller 51 is reset during repro, the external device 200 can reliably turn on the battery switch 43 and make it conductive.

[0077] The battery switch 43 is turned off by the rewriting program 52b or the external device 200. This allows the battery switch 43 to be turned off at a timing that corresponds to the progress of the rewriting performed by the rewriting program 52b. When the external device 200 turns off the battery switch 43, the timing for turning off the battery switch 43 can be set in advance. For example, the battery switch 43 can be turned off at the timing when a predetermined time has elapsed since reset and the bypass switch 42 transitions to a normal state and turns on, i.e., the timing when power is supplied from the first power source 10 to the second load 102. This allows the time during which power is supplied from the second power source 20 to the second load 102 (see period Td in FIG. 10 ) to be as short as possible, thereby reducing the power consumption of the second power source 20.

[0078] [Third embodiment] Next, a power supply control device 30 according to a third embodiment will be described with reference to Fig. 12. Fig. 12 is an explanatory diagram showing an example of the configuration and operation of a power supply system 1 including a power supply control device 30 according to the third embodiment.

[0079] 12, in the power supply control device 30 according to the third embodiment, the battery switch 43 is configured to function as a power supply mechanism 31c, as in the second embodiment. The power supply control device 30 according to the third embodiment includes a pulse output device 82 that turns on the battery switch 43 during repro. That is, the power supply mechanism 31c according to the third embodiment includes the battery switch 43 and the pulse output device 82.

[0080] Specifically, the pulse output device 82 included in the power supply mechanism 31c is provided on a control line 80 that controls the battery switch 43. The power supply mechanism 31c also includes a third switch 83a and a fourth switch 83b. The control line 80 also includes a third control line 80a and a fourth control line 80b. The third control line 80a and the fourth control line 80b are control lines that branch off from the control line 80 at a connection point p3 and connect at a connection point p4.

[0081] The third control line 80a is provided with a third switch 83a. The fourth control line 80b is provided with a pulse output device 82 and a fourth switch 83b. In other words, the third switch 83a is connected in parallel with the pulse output device 82 and the fourth switch 83b. On the fourth control line 80b, the pulse output device 82 and the fourth switch 83b are connected in series. In this way, the third control line 80a is a control line that does not have a pulse output device 82, and the fourth control line 80b is a control line that has a pulse output device 82.

[0082] Pulse output device 82 is a device capable of outputting a drive pulse for a fixed period of time that turns on battery switch 43. A one-shot multivibrator can be used as pulse output device 82. Pulse output device 82 is connected to controller 51, and when an actuation signal is input from controller 51, it outputs a one-shot pulse (drive pulse) to battery switch 43 for a fixed period of time (e.g., 50 ms). Battery switch 43 is turned on and conducts for the fixed period of time that the drive pulse is input.

[0083] In the power supply mechanism 31c configured as described above, the controller 51 enables the third control line 80a during normal operation, and enables the fourth control line 80b when reprogramming the control program 52a. Note that this normal operation includes times other than when reprogramming is performed, in other words, it includes times when reprogramming is not performed.

[0084] Specifically, although not shown, during normal operation, the controller 51 turns on the third switch 83a and turns off the fourth switch 83b, thereby activating the third control line 80a and deactivating the fourth control line 80b. As a result, when repro is not being performed, the controller 51 can output power indicating the drive signal to the battery switch 43 via the third control line 80a without any response delay, thereby controlling the battery switch 43.

[0085] 12, when the control program 52a is reprogrammed, the controller 51 disables the third control line 80a and enables the fourth control line 80b by turning off the third switch 83a and turning on the fourth switch 83b. Specifically, after enabling the fourth control line 80b, the controller 51 activates the pulse output device 82 to output a drive pulse to the battery switch 43. This turns on the battery switch 43 and makes it conductive. Therefore, power from the second power source 20 is supplied to the second load 102 via the battery switch 43. Specifically, even if a period occurs in which both the inter-system switch 41 and the bypass switch 42 are off due to the output of the control signal being stopped by a reset, the battery switch 43 becomes conductive, allowing power to be supplied from the second power source 20 to the second load 102.

[0086] The operation of the power supply system 1 during the above-described reprogramming will be described in detail with reference to Fig. 13. Fig. 13 is a time chart showing an example of the operation of the inter-system switch 41, bypass switch 42, pulse output device 82, and battery switch 43 during the reprogramming process (reprogramming) of the control program 52a. In Fig. 13, the time T0 to T31 before reprogramming is executed (requested) is during normal operation, with the third control line 80a enabled and the fourth control line 80b disabled.

[0087] 13, when the controller 51 receives a request to execute repro from the external device 200 at time T31, it disables the third control line 80a and enables the fourth control line 80b at time T32 before performing a reset. Then, with the fourth control line 80b enabled, the controller 51 outputs an activation signal to the pulse output device 82, activating the pulse output device 82. This causes the pulse output device 82 to output a drive pulse (Hi signal) to the battery switch 43 for a certain period of time (see period Te). The battery switch 43 is turned on and conducts for the certain period of time during which the drive pulse is input from the pulse output device 82. Then, with the battery switch 43 in the on state, the controller 51 performs a reset (see time T33).

[0088] At this time, the control signal output from the reset controller 51 to the inter-system switch 41 stops, so that, for example, the inter-system switch 41 may be turned off at time T33 and the bypass switch 42 may be turned on at time T34. In such a case, the inter-system switch 41 and the bypass switch 42 are both turned off during the period Ta from time T33 to time T34. However, because the battery switch 43 is turned on and conducting, power is supplied from the second power source 20 to the second load 102. In other words, it is possible to prevent a momentary interruption in the power supply to the second load 102.

[0089] Then, at time T35 after a certain period of time has elapsed, when the input of the drive pulse from the pulse output device 82 stops (the drive pulse becomes a Lo signal), the battery switch 43 turns off.

[0090] Thus, in the third embodiment, when reprinting is performed, the battery switch 43 is turned on for a certain period of time (period Te in Figure 13) by a drive pulse from the pulse output device 82, and power is supplied from the second power source 20 to the second load 102.

[0091] This certain time (period Te) includes the period Ta during which both the inter-system switch 41 and the bypass switch 42 are turned off by the reset, and is set to be longer than the period Ta, but is not limited to this. That is, the period Te may be the same as the period Ta during which both the inter-system switch 41 and the bypass switch 42 are turned off, for example.

[0092] Next, processing executed by the controller 51 of the power supply control device 30 according to the third embodiment will be described with reference to Fig. 14. Fig. 14 is a flowchart showing an example of processing executed by the controller 51 of the power supply control device 30 according to the third embodiment. This processing is executed repeatedly while the power supply control device 30 is running.

[0093] As shown in FIG. 14, the controller 51 determines whether or not a re-programming request has been received from the external device 200 (step S301). If it is determined that a re-programming request has not been received (step S301, No), that is, during normal operation, the controller 51 enables the third control line 80a (step S302). Specifically, the controller 51 enables the third control line 80a by turning on the third switch 83a. At this time, the controller 51 disables the fourth control line 80b by turning off the fourth switch 83b. As a result, during normal operation when re-programming is not being performed, the controller 51 outputs power indicating the drive signal to the battery switch 43 via the third control line 80a, thereby controlling the battery switch 43.

[0094] On the other hand, if it is determined that a request to execute repro has been received (step S301, Yes), the controller 51 enables the fourth control line 80b (step S303). Specifically, the controller 51 enables the fourth control line 80b by turning on the fourth switch 83b. At this time, the controller 51 disables the third control line 80a by turning off the third switch 83a.

[0095] Next, the controller 51 activates the pulse output device 82 (step S304). Specifically, the controller 51 outputs an activation signal to the pulse output device 82, activating the pulse output device 82. As a result, the pulse output device 82 outputs a drive pulse to the battery switch 43 for a certain period of time, and the battery switch 43 is thereby turned on and becomes conductive. In this way, the battery switch 43 becomes conductive, and thus power is supplied from the second power source 20 to the second load 102.

[0096] Next, the controller 51 executes a reset process (step S305). At this time, the control signals output from the controller 51 to the inter-system switch 41 and the bypass switch 42 are stopped. Therefore, both the inter-system switch 41 and the bypass switch 42 may be turned off, but because the battery switch 43 is turned on and conducting, power is supplied to the second load 102 from the second power source 20 (see FIG. 12).

[0097] Next, the controller 51 executes a rewrite process of the control program 52a (step S306). Specifically, the controller 51 executes the rewrite program 52b to rewrite the control program 52a. Note that the battery switch 43 turns off when the input of the drive pulse from the pulse output device 82 stops after a certain time has elapsed.

[0098] As described above, in the third embodiment, the power supply mechanism 31c is configured to include the pulse output device 82. When the controller 51 receives a request to execute reprinting, it activates the pulse output device 82 to turn on the battery switch 43 for a certain period of time, thereby supplying power from the second power source 20 to the second load 102. As a result, even if a period Ta occurs during which both the inter-system switch 41 and the bypass switch 42 are turned off due to the stop of output of the control signal due to a reset, power is supplied from the second power source 20 to the second load 102. This makes it possible to prevent a momentary interruption in the power supply to the second load 102, and as a result, to suppress the effects of a momentary interruption in the power supply on the second load 102.

[0099] Furthermore, the controller 51 enables the third control line 80a, which does not have a pulse output device 82, during normal operation, and enables the fourth control line 80b, which has a pulse output device 82, when performing a rewrite process (reprogramming) of the control program 52a. By switching the control lines to be enabled between normal operation and reprogramming in this way, it is possible to prevent the pulse output device 82 from affecting the control of the battery switch 43, for example, during normal operation.

[0100] [Fourth embodiment] Next, a power supply control device 30 according to a fourth embodiment will be described with reference to Fig. 15. Fig. 15 is an explanatory diagram showing an example of the configuration and operation of a power supply system 1 including a power supply control device 30 according to the fourth embodiment.

[0101] 15, in the power supply control device 30 according to the fourth embodiment, the battery switch 43 is configured to function as a power supply mechanism 31d, as in the second and third embodiments. The power supply control device 30 according to the fourth embodiment includes a latch circuit 86 that latches a drive signal that turns on the battery switch 43 during repro. That is, the power supply mechanism 31d according to the fourth embodiment includes the battery switch 43 and the latch circuit 86.

[0102] Specifically, the latch circuit 86 included in the power supply mechanism 31d is provided on the control line 80 that controls the battery switch 43. The power supply mechanism 31d also includes a fifth switch 87a and a sixth switch 87b. The control line 80 also includes a fifth control line 80c and a sixth control line 80d. The fifth control line 80c and the sixth control line 80d are control lines that branch off from the control line 80 at a connection point p5 and connect at a connection point p6.

[0103] The fifth control line 80c is provided with a fifth switch 87a. The sixth control line 80d is provided with a latch circuit 86 and a sixth switch 87b. In other words, the fifth switch 87a, the latch circuit 86, and the sixth switch 87b are connected in parallel. Furthermore, the latch circuit 86 and the sixth switch 87b are connected in series in the sixth control line 80d. In this way, the fifth control line 80c is a control line that does not have a latch circuit 86, and the sixth control line 80d is a control line that has a latch circuit 86.

[0104] The latch circuit 86 is a circuit that latches a drive signal that turns on the battery switch 43. Specifically, when a drive signal that turns on the battery switch 43 is input from the controller 51 to the latch circuit 86, the latch circuit 86 latches (holds) the drive signal and outputs the drive signal to the battery switch 43 as a latch signal. When the drive signal is input from the latch circuit 86, the battery switch 43 is turned on and becomes conductive. When a clear signal is input from the controller 51, the latch circuit 86 is cleared and stops outputting the drive signal. When the drive signal from the latch circuit 86 stops, the battery switch 43 turns off.

[0105] In the power supply mechanism 31d configured as described above, the controller 51 enables the fifth control line 80c during normal operation, and enables the sixth control line 80d when reprogramming of the control program 52a is performed. Note that this normal operation includes times other than when reprogramming is performed, in other words, it includes times when reprogramming is not performed.

[0106] Specifically, although not shown, during normal operation, the controller 51 turns on the fifth switch 87a and turns off the sixth switch 87b, thereby enabling the fifth control line 80c and disabling the sixth control line 80d. As a result, when repro is not being performed, the controller 51 can output power indicating the drive signal to the battery switch 43 via the fifth control line 80c without a response delay, thereby controlling the battery switch 43.

[0107] 15, when the control program 52a is reprogrammed, the controller 51 disables the fifth control line 80c and enables the sixth control line 80d by turning off the fifth switch 87a and turning on the sixth switch 87b. Specifically, after enabling the sixth control line 80d, the controller 51 outputs a drive signal for the battery switch 43 to the latch circuit 86. The latch circuit 86 latches the input drive signal and outputs it to the battery switch 43. This turns on the battery switch 43 and makes it conductive. Therefore, power from the second power source 20 is supplied to the second load 102 via the battery switch 43. Specifically, even if a period occurs in which both the inter-system switch 41 and the bypass switch 42 are off due to the output of the control signal being stopped by a reset, the battery switch 43 becomes conductive, allowing power to be supplied from the second power source 20 to the second load 102.

[0108] The operation of the power supply system 1 during the above-described repro will be described in detail with reference to Fig. 16. Fig. 16 is a time chart showing an example of the operation of the inter-system switch 41, bypass switch 42, latch circuit 86, and battery switch 43 during the rewrite process (repro) of the control program 52a. In Fig. 16, the time T0 to T41 before repro is executed (requested) is during normal operation, and the fifth control line 80c is enabled and the sixth control line 80d is disabled.

[0109] 16, when the controller 51 receives a request to execute repro from the external device 200 at time T41, the controller 51 disables the fifth control line 80c and enables the sixth control line 80d at time T42 before performing a reset. Then, with the sixth control line 80d enabled, the controller 51 outputs a drive signal for the battery switch 43 to the latch circuit 86. The latch circuit 86 latches the input drive signal and outputs the latched drive signal (Hi signal) to the battery switch 43. This turns on the battery switch 43 and makes it conductive. Then, with the battery switch 43 in the on state, the controller 51 performs a reset (see time T43).

[0110] At this time, the control signal output from the reset controller 51 to the inter-system switch 41 stops, so that, for example, the inter-system switch 41 may be turned off at time T43 and the bypass switch 42 may be turned on at time T44. In such a case, the inter-system switch 41 and the bypass switch 42 are both turned off during the period Ta from time T43 to time T44. However, because the battery switch 43 is turned on and conducting, power is supplied from the second power source 20 to the second load 102. In other words, it is possible to prevent a momentary interruption in the power supply to the second load 102.

[0111] Then, at time T45, the battery switch 43 is turned off by the rewriting program 52b used in the rewriting process. More specifically, the controller 51 executes the rewriting program 52b to output a clear signal to the latch circuit 86. When the clear signal is input, the latch circuit 86 is cleared and stops outputting the drive signal, thereby turning off the battery switch 43. In this way, the latch circuit 86 is cleared by the rewriting program 52b.

[0112] As described above, in the fourth embodiment, when reprogramming is performed, the battery switch 43 is turned on for a certain period of time in response to the drive signal output from the latch circuit 86, and power is supplied from the second power supply 20 to the second load 102. In the example of Fig. 16, the certain period of time is the period Tf from time T42 when the drive signal is output from the latch circuit 86 and the battery switch 43 is turned on, to time T45 when the latch circuit 86 is cleared by the rewrite program 52b and the battery switch 43 is turned off.

[0113] The period Tf includes the period Ta in which both the inter-system switch 41 and the bypass switch 42 are turned off by the reset, and is set to be longer than the period Ta, but is not limited to this. That is, the period Td may be the same as the period Ta in which both the inter-system switch 41 and the bypass switch 42 are turned off, for example.

[0114] Next, processing executed by the controller 51 of the power supply control device 30 according to the fourth embodiment will be described with reference to Fig. 17. Fig. 17 is a flowchart showing an example of processing executed by the controller 51 of the power supply control device 30 according to the fourth embodiment. This processing is executed repeatedly while the power supply control device 30 is running.

[0115] As shown in FIG. 17, the controller 51 determines whether a request to execute repro- duction has been received from the external device 200 (step S401). If it is determined that a request to execute repro- duction has not been received (step S401, No), that is, during normal operation, the controller 51 enables the fifth control line 80c (step S402). More specifically, the controller 51 enables the fifth control line 80c by turning on the fifth switch 87a. At this time, the controller 51 disables the sixth control line 80d by turning off the sixth switch 87b. As a result, during normal operation when repro- duction is not being performed, the controller 51 outputs power indicating the drive signal to the battery switch 43 via the fifth control line 80c, thereby controlling the battery switch 43.

[0116] On the other hand, if it is determined that a request to execute repro has been received (step S401, Yes), the controller 51 enables the sixth control line 80d (step S403). Specifically, the controller 51 enables the sixth control line 80d by turning on the sixth switch 87b. At this time, the controller 51 disables the fifth control line 80c by turning off the fifth switch 87a.

[0117] Next, the controller 51 outputs a drive signal for the battery switch 43 to the latch circuit 86 (step S404). As a result, the latch circuit 86 latches the input drive signal and outputs it to the battery switch 43, which then turns on the battery switch 43 and becomes conductive. In this way, as the battery switch 43 becomes conductive, power is supplied from the second power source 20 to the second load 102.

[0118] Next, the controller 51 executes a reset process (step S405). At this time, the control signals output from the controller 51 to the inter-system switch 41 and the bypass switch 42 are stopped. Therefore, both the inter-system switch 41 and the bypass switch 42 may be turned off, but because the battery switch 43 is turned on and conducting, power is supplied to the second load 102 from the second power source 20 (see FIG. 15).

[0119] Next, the controller 51 executes rewriting (rewriting process) of the control program 52a (step S406). Specifically, the controller 51 executes the rewriting program 52b to rewrite the control program 52a. Next, the controller 51 executes the rewriting program 52b to output a clear signal to the latch circuit 86 (step S407). This clears the latch circuit 86 and stops outputting the drive signal, thereby turning off the battery switch 43.

[0120] As described above, in the fourth embodiment, the power supply mechanism 31d is configured to include the latch circuit 86. When the controller 51 receives a request to execute re-programming, it outputs a drive signal to the latch circuit 86, thereby turning on the battery switch 43 and supplying power from the second power source 20 to the second load 102. As a result, even if a period Ta occurs during which both the inter-system switch 41 and the bypass switch 42 are turned off due to the output of the control signal being stopped by a reset, power is supplied from the second power source 20 to the second load 102. This makes it possible to prevent a momentary interruption in the power supply to the second load 102, and as a result, to suppress the effects of a momentary interruption in the power supply on the second load 102.

[0121] Furthermore, the controller 51 enables the fifth control line 80c, which does not have a latch circuit 86, during normal operation, and enables the sixth control line 80d, which has a latch circuit 86, when performing a rewrite process (reprogramming) of the control program 52a. By switching the control lines to be enabled between normal operation and reprogramming in this way, it is possible to prevent the latch circuit 86 from affecting the control of the battery switch 43, for example, during normal operation.

[0122] [Modification of the fourth embodiment] Next, a power supply control device 30 according to a modification of the fourth embodiment will be described with reference to Fig. 18. Fig. 18 is an explanatory diagram showing an example of the configuration and operation of a power supply system 1 including a power supply control device 30 according to a modification of the fourth embodiment. Note that, here, components common to the fourth embodiment will be assigned the same reference numerals and descriptions thereof may be omitted.

[0123] 18, in a power supply control device 30 according to the modification, a power supply mechanism 31d1 includes a battery switch 43 and a latch circuit 86, similar to the fourth embodiment. The latch circuit 86 is provided on a control line 80 that controls the battery switch 43. Furthermore, the power supply mechanism 31d1 according to the modification is configured without the fifth switch 87a and the sixth switch 87b of the fourth embodiment.

[0124] During normal operation and when reprogramming is being performed, the controller 51 outputs a drive signal or clear signal for the battery switch 43 to the latch circuit 86, thereby controlling the battery switch 43. In other words, the controller 51 according to the modified example controls the battery switch 43 via the latch circuit 86 even during normal operation when reprogramming is not being performed.

[0125] The process executed by the controller 51 according to the modification will be described with reference to Fig. 19. Fig. 19 is a flowchart showing an example of the process executed by the controller 51 of the power supply control device 30 according to the modification of the fourth embodiment. This process is executed repeatedly while the power supply control device 30 is running.

[0126] 19, the controller 51 determines whether or not a request to execute re-programming has been received from the external device 200 (step S401). If it is determined that a request to execute re-programming has not been received (step S401, No), that is, during normal operation, the controller 51 determines whether or not it is necessary to turn on the battery switch 43 (step S402a). Here, the controller 51 determines that it is necessary to turn on the battery switch 43 when, for example, a power failure in the first system 110 is detected.

[0127] When it is determined that the battery switch 43 needs to be turned on (Yes in step S402a), the controller 51 executes the control program 52a to output a drive signal for the battery switch 43 to the latch circuit 86 (step S402b). As a result, the latch circuit 86 latches the input drive signal and outputs it to the battery switch 43, which turns on the battery switch 43 and makes it conductive. In this way, when the battery switch 43 is conductive, power is supplied from the second power source 20 to the second load 102.

[0128] If it is determined that there is no need to turn on the battery switch 43 (No in step S402a), the controller 51 skips the process in step S402b.

[0129] Next, the controller 51 determines whether or not it is necessary to turn off the battery switch 43 (step S402c). Here, the controller 51 determines that it is necessary to turn off the battery switch 43 when, for example, the power supply failure of the first system 110 is resolved.

[0130] If it is determined that the battery switch 43 needs to be turned off (Yes in step S402c), the controller 51 executes the control program 52a to output a clear signal to the latch circuit 86 (step S402d). This clears the latch circuit 86 and stops the output of the drive signal, thereby turning off the battery switch 43.

[0131] If it is determined that there is no need to turn off the battery switch 43 (No in step S402c), the controller 51 skips the process of step S402d.

[0132] On the other hand, if it is determined that a request to execute repro has been received (Yes in step S401), the controller 51 executes the control program 52a before the reset process, thereby outputting a drive signal for the battery switch 43 to the latch circuit 86 (step S404). As a result, the latch circuit 86 latches the input drive signal and outputs it to the battery switch 43, which turns on the battery switch 43 and becomes conductive. In this way, as the battery switch 43 becomes conductive, power is supplied from the second power source 20 to the second load 102.

[0133] Next, the controller 51 performs a reset process in step S405 and a process of rewriting the control program 52a in step S406. Next, the controller 51 executes the rewriting program 52b to output a clear signal to the latch circuit 86 (step S407). This clears the latch circuit 86 and stops outputting the drive signal, thereby turning off the battery switch 43.

[0134] In the modified example, the time chart showing an example of the operations of the inter-system switch 41, the bypass switch 42, the latch circuit 86, and the battery switch 43 during reproduction is the same as that shown in FIG.

[0135] As described above, in this modification of the fourth embodiment, when the controller 51 turns on the battery switch 43 during normal operation, it outputs a drive signal to the latch circuit 86, thereby turning on the battery switch 43 and making it conductive. When the controller 51 turns off the battery switch 43, the control program 52a clears the latch circuit 86. As described above, in this modification, the latch circuit 86 is involved in controlling the battery switch 43 during normal operation, and although there is a slight response delay during normal operation compared to the fourth embodiment, the configuration can be simplified.

[0136] [Fifth embodiment] Next, a power supply control device 30 according to a fifth embodiment will be described with reference to Fig. 20. Fig. 20 is an explanatory diagram showing an example of the configuration and operation of a power supply system 1 including a power supply control device 30 according to the fifth embodiment.

[0137] 20, the power supply control device 30 according to the fifth embodiment is configured not to include the power supply mechanism according to the first to fourth embodiments. In the power supply control device 30 according to the fifth embodiment, the controller 51 of the microcomputer 50 and the second load 102 are communicatively connected via a communication line 102a.

[0138] When reprogramming the control program 52a, the controller 51 notifies the second load 102 that there is a possibility of a momentary interruption in the power supply to the second load 102. In detail, the controller 51 notifies the second load 102 by outputting a signal indicating that there is a possibility of a momentary interruption in the power supply to the second load 102.

[0139] Upon receiving this notification, the second load 102 recognizes that the power interruption is due to a repro and not an abnormality. Therefore, the second load 102 does not perform any processing to deal with the power interruption, such as detecting the power interruption and storing it as diagnostic information. This makes it possible to suppress the impact of the power interruption on the second load 102.

[0140] Next, processing executed by the power supply system 1 according to the fifth embodiment will be described with reference to Fig. 21. Fig. 21 is a diagram showing an example of a processing sequence executed by the power supply system 1 including the power supply control device 30 according to the fifth embodiment.

[0141] 21, the external device 200 outputs a request to execute re-processing to the controller 51 (step S501). When the controller 51 receives the request to execute re-processing from the external device 200, it notifies the second load 102 that there is a possibility of an instantaneous interruption in the power supply to the second load 102 (step S502). Upon receiving the notification, the second load 102 temporarily stops the instantaneous interruption response process (step S503).

[0142] Next, the controller 51 executes a reset process (step S504). At this time, the control signals output from the controller 51 to the inter-system switch 41 and the bypass switch 42 are stopped. Therefore, both the inter-system switch 41 and the bypass switch 42 may be turned off, causing a momentary interruption in the power supply to the second load 102. However, even if the second load 102 detects such a momentary interruption, it does not perform a process to deal with the momentary interruption.

[0143] Next, the controller 51 executes a rewrite process of the control program 52a (step S505). Specifically, the controller 51 executes the rewrite program 52b to rewrite the control program 52a.

[0144] As described above, in the fifth embodiment, when the controller 51 performs the rewrite process of the control program 52a, it notifies the second load 102 that there is a possibility of a momentary interruption in the power supply to the second load 102. As a result, the second load 102, upon receiving the notification, can recognize that the momentary interruption is not due to an abnormality. Therefore, it is possible to prevent the second load 102 from performing a momentary interruption response process, thereby suppressing the influence of the momentary interruption in the power supply to the second load 102.

[0145] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0146] 30 Power supply control device 41 Intersystem switch 42 Bypass switch 51 Controller

Claims

1. a normally open inter-system switch provided on an inter-system line connecting a first system that supplies power from a first power source to a first load and a second system that supplies power from a second power source to a second load; a normally closed bypass switch connected in parallel to the inter-system switch; a controller that outputs control signals for controlling the inter-system switch and the bypass switch in accordance with a control program and is reset when a rewrite process of the control program is performed; a power supply mechanism that supplies power to the second load during a period in which the inter-system switch and the bypass switch are both turned off due to the stop of output of the control signal caused by a reset when the rewrite process of the control program is performed in the controller; A power supply control device comprising:

2. The power supply mechanism includes: A delay circuit is provided on a control line that controls the inter-system switch, and delays the stop of output of the control signal due to reset for a certain period of time. The power supply control device according to claim 1 .

3. The control line that controls the inter-system switch is a first control line not having the delay circuit and a second control line having the delay circuit; The controller The first control line is enabled during normal operation, and the second control line is enabled when the rewrite process of the control program is performed. The power supply control device according to claim 2 .

4. The power supply mechanism includes: a battery switch for connecting the second power supply to the second system; When the rewriting process of the control program is performed in the controller, the battery switch is turned on for a certain period of time to supply power from the second power source to the second load. The power supply control device according to claim 1 .

5. The battery switch is The power supply is turned on and becomes conductive by an external device that controls the rewriting process of the control program by the controller, and is turned off by a program used in the rewriting process or the external device. The power supply control device according to claim 4.

6. The power supply mechanism includes: a pulse output device that can output a drive pulse to the battery switch for a certain period of time to turn on the battery switch; The controller When a request to execute the rewrite process of the control program is received, the pulse output device is operated to turn on the battery switch for a certain period of time to make it conductive. The power supply control device according to claim 4.

7. a third control line that controls the battery switch and does not have the pulse output device, and a fourth control line that controls the battery switch and has the pulse output device are connected to the controller; The controller the third control line is enabled during normal operation, and the fourth control line is enabled when the rewrite process of the control program is performed; The power supply control device according to claim 6.

8. The power supply mechanism includes: a latch circuit that latches a drive signal that turns on the battery switch; The controller When a request to execute the rewrite process of the control program is received, the drive signal is output to the latch circuit, thereby turning on the battery switch and making it conductive, and the latch circuit is cleared by the program used for the rewrite process. The power supply control device according to claim 4.

9. a fifth control line that controls the battery switch and does not have the latch circuit, and a sixth control line that controls the battery switch and has the latch circuit are connected to the controller; The controller The fifth control line is enabled during normal operation, and the sixth control line is enabled when the rewrite process of the control program is performed. The power supply control device according to claim 8.

10. The controller During normal operation, when the battery switch is turned on, the drive signal is output to the latch circuit, thereby turning on the battery switch and making it conductive, and when the battery switch is turned off, the latch circuit is cleared by the control program. The power supply control device according to claim 8.

11. a normally open inter-system switch provided on an inter-system line connecting a first system that supplies power from a first power source to a first load and a second system that supplies power from a second power source to a second load; a normally open bypass switch connected in parallel to the inter-system switch; a controller that outputs a control signal for controlling the inter-system switch and the bypass switch in accordance with a control program and is reset when a rewrite process of the control program is performed; Equipped with The controller When the rewriting process of the control program is performed, a notification is given that there is a possibility of a momentary interruption in the power supply to the second load. Power control device.

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