JPH0373502B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a vehicle load drive control device that ensures stable driving of a vehicle load. [Technical Background of the Invention and Problems Therewith] Vehicles are usually provided with a power supply section consisting of a battery and an alternator, which supplies power to each on-vehicle load during driving. In other words, when the alternator is in a power generation state, power is supplied to each on-vehicle load by the alternator, while when it is not in a power generation state, power is supplied from the battery to each on-vehicle load. Incidentally, the power supply voltage in the power supply section generally fluctuates by about 10 to 15 volts depending on the ON/OFF state of the on-vehicle load. This is particularly noticeable due to the increase in on-vehicle loads due to the enrichment of equipment in vehicles in recent years, but among on-vehicle loads, there are usually lamp loads such as headlamps and inductive loads such as motors that require large amounts of power. When an object starts to be driven, an inrush current that is several to several tens of times larger than a steady state occurs, resulting in a temporary voltage drop in the power path from the power supply section to the on-vehicle load. However, this voltage level becomes extremely large when multiple on-vehicle loads that require large amounts of power are started to be driven at the same time, and there is a fear that the driving of other on-vehicle loads may be affected. In particular, recent vehicles tend to be equipped with various electronic control devices controlled by microcomputers, etc.
Generally, these microcomputers need to secure a predetermined power supply voltage in order to operate normally. Therefore, if a significant voltage drop as described above occurs, normal operation may not be guaranteed, and it is necessary to take some countermeasures. In addition, for in-vehicle loads that often operate at the same time, such as door lock solenoids and power window motors, voltage drops should be taken into consideration in advance to ensure stable operation even when such voltage drops occur. Measures must be taken at various locations such as the harness, which may lead to increased costs. [Object of the Invention] This invention has been made in view of the above, and its first object is to provide a load drive control device for a vehicle that suppresses a power supply voltage drop due to an inrush current that occurs when driving an on-vehicle load. Our goal is to provide the following. A second object of the present invention is to provide a load drive control device for a vehicle that prevents a significant power supply voltage drop due to an inrush current that occurs when driving an on-vehicle load when the on-vehicle power source lacks power supply capacity. It's about doing. [Summary of the invention] In order to achieve the above first object, the present invention has the following features:
As shown in FIG. 1a, a power supply control means 3 is provided which conducts/cuts off the power supply path from the on-vehicle power supply means 1 to each on-vehicle load 5-1 to 5-n, and the conduction control means 9 determines whether or not it is necessary to start driving the load. The power supply control means 3 is controlled based on the drive command signal for the on-vehicle load that requires the start of driving outputted from the detection means 7, and a plurality of drive command signals are almost simultaneously inputted by the simultaneous input detection means 8. The gist is that when a drive command is detected, the power supply path for the on-vehicle load for which a drive command has been issued is sequentially made conductive at predetermined set times based on the priority drive order information stored in the priority drive order storage means 6. do. In order to achieve the above second objective, this invention
As shown in FIG. 1b, a power supply control means 13 is provided to conduct/cut off the power supply path from the on-vehicle power supply means 11 to each on-vehicle load 15-1 to 15-n, and the power supply capability of the on-vehicle power supply means 11 is detected. When the detected power supply capacity has not reached a predetermined level, the continuity control means 20 outputs predetermined on-vehicle load priority driving order information and load drive start necessity detection means 17. controlling the power supply control means 13 based on the drive command signal for the on-vehicle load that requires the start of drive;
The gist is that the power supply paths for the on-vehicle loads for which drive commands have been received are sequentially made conductive. [Embodiments of the Invention] Examples of the invention will be described below with reference to the drawings. FIG. 2 shows a first embodiment of the invention. In the figure, 21 is an in-vehicle battery;
Reference numeral 23 denotes an alternator, and together they constitute a power supply section 25 for supplying power to an on-vehicle load, which will be described later. As shown in Table 1, the on-vehicle loads to which power is supplied by the power supply unit 25 include a power load group 27 whose operation timing directly affects the vehicle running function (hereinafter referred to as "essential load group"); They are classified in advance into a power load group (hereinafter referred to as "allowable load group") 29 whose operation timing does not directly affect the vehicle running function.

【table】

[Table] And each load 29-1 of the permissible load group 29
~29-n includes a power supply unit 25 for each load.
Load switching circuits 31-1 to 31-n are connected in series to conduct/interrupt the power supply path from the power supply section 25. 33 is the required load 27-1 to 2
Operation command signal from 7-n and the allowable load 2
The load start circuits 31-1 to 31-n are turned on and off by performing the process described later based on the input of the operation signal from the load operation switches 35-1 to 35-n that start the operation of the load start circuits 31-1 to 29-n. This is a control circuit that performs cut-off control. Note that the control circuit 33 includes, for example, a CPU.
37, ROM39, RAM41, input port 43,
45 and an output port 47. Next, the operation of this embodiment will be explained using FIG. 3. Incidentally, FIG. 3 shows a processing flowchart of the CPU 37. The ignition key (not shown) is turned on,
After the initial settings (not shown) are made by setting the registers, counters, latches, etc. in the CPU 37 to a computable state and resetting each constant, when the activation signal is input, interrupt processing (INT) is performed. enter. In the interrupt processing, first, the status of the start of input of the actuation signal is determined. Based on this grasped situation, when it is determined that the load operation switches corresponding to the plurality of allowable loads in the allowable load group 29 are activated almost simultaneously in order to start operating the plurality of allowable loads, the load operating switches corresponding to the plurality of allowable loads are activated almost simultaneously. Based on the order of start of operation of the allowable loads, that is, the order of start of operation of the allowable loads, that is, the order of start of operation at sequentially shifted timings, starting from the allowable load with the shortest delay time based on Table 1 above.
R _L1 , R _L2 -, R _LN are determined (step 100). Next, the process proceeds to step 110, where it is confirmed that all allowable loads corresponding to the actuated load actuating switches are not yet in the actuated state, and the process proceeds to step 12.
Go to 0. In step 120, the essential loads 27-1 to 27-n are changed so that the operations of the essential loads 27-1 to 27-n are not affected by the start of the operation of the allowable loads.
1 to 27-n are turned off and the load start circuit corresponding to the permissible load is made conductive in order to start the permissible load according to the previously determined priority order, and the process proceeds to step 130. In step 130, a predetermined timer is started, and after the set time Ts in the timer has elapsed, the process returns to step 110 in order to start operating the allowable load with the next highest priority. That is, in step 130, when the rush current of the allowable load started in step 120 is flowing, another allowable load having the next highest priority is prevented from being started. Then, through the processing loop of steps 110 to 130, the permissible loads with the highest priority are sequentially started to operate, and when all the permissible loads with the determined priorities have started driving, the determination in step 110 is not satisfied (ON). state, and the interrupt processing ends. Next, the above-described processing will be specifically explained using the operation time charts A to F in FIG. 4. In addition, in the same figure, A is the essential load 27-1 to 27
-n operation command signal, B is the relevant essential load 27-1
~27-n operating current signals, C and D are conductive signals and operating current signals, respectively, of the headlamp shown with permissible load 29-1, E and F are permissible load 2
9-n are the conduction signal and operating current signal of the intermittent wiper, respectively. That is, when the essential loads 27-1 to 27-n start operating (see A and B in FIG. 4), for example, the load operating switch 35-1 of the headlamp 29-1 and the load operating switch 35- of the intermittent wiper 29-n are activated.
When n are activated at approximately the same time at times t ₁ and t _2, respectively, both allowable loads do not start operating immediately (see C and E in Figure 4), but the allowable delay time of both allowable loads first increases. (See Table 1)
Decide on priorities based on Specifically, while the allowable delay time for the headlamp 29-1 is several tens of milliseconds, the allowable delay time for the intermittent wiper 29-n is several tens of milliseconds.
Since it is 100ms, the priority is headlamp 2.
9-1 becomes higher. And essential load 27-1~
27-n, a conduction signal is sent to the load switching circuit 31-1 at time _t3 to start driving the headlamp 29-1, which has a higher priority.
Start outputting from. As a result, head lamp 2
At 9-1, power supply from the power supply unit 25 is started, and the operating current starts flowing from time _t3 (Fig. 4D).
reference). When the headlamp 29-1 starts operating, the headlamp 29-1 is turned on, avoiding the time when the rush current is flowing.
After the set time Ts (time t ₄ ) in which the -1 operating current is stabilized, the intermittent wiper 29-n attempts to start operating. However, at this time, the required load 27
-1 to 27-n, the load switching circuit 3 is in order to start operating the intermittent wiper 29-n.
No conductive signal is output to 1-n (see Fig. 4E). Therefore, after waiting for the operation current to stop flowing through the essential loads 27-1 to 27-n (time _t5 ), a conduction signal is output to the load start circuit 31-n, and the power supply unit 25 outputs a conduction signal to the intermittent wiper 29. -Start power supply to n. As a result, an operating current begins to flow through the intermittent wiper 29-n from time _t5 (see FIG. 4F). Therefore, according to this embodiment, the order of priority is stored in advance for starting the operation for the allowable loads, and when the actuation signals from the load operation switches conflict, the operation is started within the conflicting allowable loads. The order is determined, and the operations are started in the determined order so as not to affect the operation of the essential loads. Therefore, a significant voltage drop does not occur in the power supply path from the power supply section 25 to the essential load group 27 and the permissible load group 29 at the start of the operation, thereby preventing the operation of other loads from being affected. While preventing this, it is possible to ensure appropriate start of load operation. Also, battery deterioration is reduced. FIG. 5 shows a second embodiment of the present invention, which is characterized by monitoring the power supply capacity from the power supply section 55 to the essential load group 57 and the permissible load group 59, and When the permissible loads 59-1 to 59-n conflict with each other in starting operations in a state of insufficient load, the priority order for starting the operations is determined and the operations are started in accordance with the order of priority. In Fig. 5, 51 is an in-vehicle battery, 53
is an alternator, and together they constitute a power supply section 55 for a vehicle-mounted load, which will be described later. As shown in Table 1 above, the in-vehicle loads to which power is supplied by the power supply section 55 include a group of power loads (hereinafter referred to as "essential load group") 57 whose operation timing directly affects the vehicle running function. and,
A group of electric power loads whose activation timing does not directly affect the vehicle running function (hereinafter referred to as “allowable load group”) 59
It is pre-classified into. Each of the loads 59-1 to 59-n of the permissible load group 59 is connected to a power supply path from the power supply section 55 to each load.
Load switching circuits 61-1 to 61-n to be cut off are connected in series. 63 is a rotation speed signal from an engine rotation detector 79 that detects the engine rotation speed, a voltage signal from a voltage detector 81 that detects the terminal voltage of the battery 51, and essential loads 57-1 to 57.
- the operation command signal from n and the allowable load 59;
-1 to 59-n, the load switching circuit 6 performs the process described later based on the input of the operation signal of the load operation switches 65-1 to 65-n.
This is a control circuit that controls conduction/cutoff of 1-1 to 61-n. Note that the control circuit 33 includes, for example, the CPU 67,
ROM69, RAM71, input ports 73, 75,
It consists of a microcomputer with a main port 77. Next, the operation of this embodiment will be explained using the processing flowchart of the CPU 77 shown in FIGS. 6 and 7. Note that FIG. 6 shows a process for determining the power supply capability state of the power supply unit 55. FIG. 7 shows processing for controlling the start of operation of the essential loads 57-1 to 57-n and the allowable loads 59-1 to 59-n. Regarding the power supply capability status determination process shown in Figure 6, the ignition key (not shown) is turned on.
This is carried out by interrupt processing at predetermined time intervals after the processing is set (not shown) by making the registers, counters, latches, etc. in the CPU 77 operable and resetting each constant. That is, in this process, first, the terminal voltage of the battery 51 detected by the voltage detector 81 is read, and it is determined whether this voltage is equal to or higher than the set voltage (steps 200 and 210). In this judgment, if the terminal voltage is higher than the set voltage, step 2
The process proceeds to step 20, but if the opposite is true, the process proceeds to step 250, where a flag F indicating insufficient power supply capacity is set and the interrupt process is terminated. Proceeding to step 220, the engine speed detected by the engine speed detector 79 is read, and
It is determined whether the current engine rotation speed is equal to or higher than the set rotation speed (steps 220 and 230). As a result,
If the current engine rotation speed is equal to or higher than the set rotation speed, the process proceeds to step 240, where the flag F is reset and the interrupt process ends; however, in the opposite case, the process proceeds to step 250, where the flag F is set. Ends interrupt processing. Therefore, the above-mentioned processing (steps 200 to 200)
250), the terminal voltage of the battery 51 is set to such an extent that even when the power generation capacity of the alternator 53 is reduced, power can be stably supplied to the on-vehicle load at the start of operation without affecting the operation of other on-vehicle loads. Current alternator 5 assuming high
After confirming that the power supply capacity in step 3 is sufficient, the flag F is reset. In this way, when the operation signal is input while the power supply unit 55 is performing the process of determining the power supply capability state at predetermined time intervals, the interrupt process for operation start control shown in FIG. INT). When entering this interrupt processing, first, the flag F
(step 300). As a result of this determination, if the flag F is in the reset state, the power supply capacity to the on-vehicle load is sufficient, so step 35 is performed.
0, and outputs a conduction signal to the load switching circuit whose operation is to be started in order to start the operation of the allowable load according to the input of the operation signal. As a result, the allowable load starts operating without any time delay after the load operating switch is operated. On the other hand, if the flag F is in the set state, the power supply capacity is insufficient, so the process proceeds to step 310 and the start of operation of the allowable load is controlled. Proceeding to step 310, first, the situation at which input of the actuation signal starts is ascertained. From this grasped situation, when it is determined that the load operation switches corresponding to the plurality of allowable loads in the allowable load group 59 are activated almost simultaneously in order to start operating the plurality of allowable loads, the load operating switches corresponding to the plurality of allowable loads are activated almost at the same time. Based on the order of start of operation of a certain allowable load, that is, the order of start of operation of a certain allowable load, that is, the priority order R _L1 , in order to start operation by shifting the timing sequentially from the allowable load with the shortest delay time based on the above-mentioned Table 1.
R _L2 , ~, R _LN ) are determined. Next, the process proceeds to step 320, where it is confirmed that all allowable loads corresponding to the actuated load actuating switches are not yet in the actuated state, and the process proceeds to step 33.
Go to 0. In step 330, the essential loads 57-1 to 57-n are changed so that the operations of the essential loads 57-1 to 57-n are not affected by the start of the operation of the allowable loads.
1 to 57-n are turned off and the load switching circuit corresponding to the permissible load is brought into conduction in order to start operating the permissible load according to the previously determined priority order, and the process proceeds to step 340. In step 340, a predetermined timer is started, and after the set time Ts in the timer has elapsed, the process returns to step 320 in order to start operating the allowable load with the next highest priority. That is, in step 340, when the rush current of the allowable load started in step 330 is flowing, another allowable load having the next highest priority is prevented from being started. Then, through the processing loop of steps 320 to 340, the permissible loads with the highest priority are sequentially started to operate, and when all the permissible loads with the determined priorities have started driving, the determination in step 320 is not satisfied (NO). state, and the interrupt processing ends. Therefore, according to this embodiment, the predetermined priority is applied only when the power supply capacity to the essential load group and the allowable load group in the power supply unit is insufficient and the permissible loads are in conflict with each other. According to the order, the allowable loads are staggered and the operations are started sequentially. Therefore, when the power supply capacity of the power supply section is sufficient, the allowable load starts operating immediately by operating the switch, so it is possible to keep the time delay at the start of operation to the necessary minimum, and also to This can prevent the operation of the load from being affected. [Effects of the Invention] As described above, according to the present invention, when there is a conflict in the drive start of the on-vehicle loads, the drive start order is determined based on predetermined drive priority information of the on-vehicle loads, Since the on-vehicle loads are started to be driven one after another in accordance with this determined order, it is possible to suppress the power supply voltage drop due to the large inrush current that occurs when multiple on-vehicle loads, especially on-vehicle loads that require large amounts of power, are started to be driven at the same time. It does not affect the operation of other on-vehicle loads. Further, according to the present invention, the drive start control of the on-vehicle load according to the drive start order is performed when the power supplied by the on-vehicle power source is decreasing, so that unnecessary start of drive of the on-vehicle load is avoided. While eliminating delays, it is possible to prevent a significant power supply voltage drop due to rush current that occurs when driving an on-vehicle load when the on-vehicle power supply capacity is insufficient. Although it is expected that various electronic control systems will be widely adopted in vehicles in the future, it is thought that the power supply capacity of vehicles will not increase much due to weight restrictions and fuel efficiency constraints. Considering this, it seems that the temporal dispersion of power consumption as intended by the present invention will be very effective.

[Brief explanation of drawings]

Fig. 1 a and b are claim correspondence diagrams, Fig. 2 is a configuration diagram of the first embodiment of the present invention, Fig. 3 is a processing flowchart in the first embodiment, and Fig. 4 is a diagram showing the first embodiment of the present invention. FIG. 5 is a block diagram of a second embodiment of the present invention, and FIGS. 6 and 7 are processing flow charts of the second embodiment. DESCRIPTION OF SYMBOLS 1...Load power supply means, 3...Power supply control means, 5...Vehicle load, 7...Load drive start necessity detection means, 9...Current control means, 11...Vehicle power supply means, 13...Power supply control means, 15...Vehicle load, 17... Load drive start necessity detection means, 19... Power supply capability detection means, 20... Current control means.

Claims (1)

[Scope of Claims] 1. An on-vehicle power supply means for supplying power to a plurality of on-vehicle loads, a power supply control means for conducting/cutting off a power supply path from the on-vehicle power supply means to each on-vehicle load, and a key for starting driving of each on-vehicle load. load drive start necessity detection means for detecting whether or not driving is required and outputting a drive command signal for an on-vehicle load that requires drive start; and outputting a simultaneous input signal when detecting that multiple drive command signals are input almost simultaneously. a simultaneous input detection means for detecting the driving of each on-vehicle load; a priority driving order storage means for storing a priority order for starting driving of each on-vehicle load as priority driving order information; and when the simultaneous input signal is not input, the power feeding control means is controlled. conducts the power supply path for the on-vehicle load to which the drive command signal has been inputted, and when the simultaneous input signal is inputted, controls the power supply control means to conduct the power supply path for the onboard load to which the drive command signal has been inputted. A load drive control device for a vehicle, comprising: a conduction control means that sequentially conducts conduction at predetermined set time intervals based on the priority drive order information. 2. An on-vehicle power supply means that supplies power to a plurality of on-vehicle loads, a power supply control means that conducts or cuts off a power supply path from the on-vehicle power supply means to each on-vehicle load, and detects whether or not it is necessary to start driving each on-vehicle load; load drive start necessity detection means for outputting a drive command signal for an on-vehicle load that requires drive start; a power supply capability detection means for detecting power supply capability of the vehicle-mounted power supply means; and a power supply capability detection means that detects that the detected power supply capability has not reached a predetermined level. In some cases, the vehicle may include a conduction control means that controls the power supply control means based on predetermined drive priority information of the on-vehicle loads and a drive command signal to sequentially conduct the power supply paths for the on-vehicle loads for which a drive command has been received. Vehicle load drive control device.