JP2596427B2 - Vehicle generator control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a generator control device for a vehicle that can prevent insufficient charging at the time of deterioration without overloading a battery in a normal state. .

[Related Art] Generally, a generator control device that controls a generator that is rechargeably connected to a battery of a vehicle has a battery and a generator connected in parallel to an electric load. Conventionally, the power generation voltage of such a generator is often fixed at a fixed voltage, but recently, the power generation voltage is changed so that the voltage applied to the load is constant according to the voltage of the battery. There is also one configured. Further, for example, as disclosed in Japanese Patent Application Laid-Open No. 59-222099, a total load current supplied to a load is detected, and a field of a generator is adjusted in accordance with the detected value to switch a generated voltage. There is also one configured. Normal,
In these generator control devices, when the battery discharges and its electromotive force drops to a predetermined value, current flows through the field coil of the generator, and the current generated by the generator causes the current to flow to the load and the battery to be discharged. It is configured to be charged.

[Problems to be solved by the invention]

By the way, in recent vehicles such as automobiles, since electric components are large and power consumption is large, performance such as electric quantity and durability of a battery is very important, and sufficient charging can be performed even when the battery is deteriorated. It is requested that

However, in the above-described conventional generator control device, the charging voltage is normally set to a constant value. Therefore, when the battery deteriorates, a chemical reaction in the battery hardly occurs, and the battery is charged to a predetermined charging voltage. However, it is difficult to store electricity, and the self-discharge phenomenon becomes remarkable, so that the battery is discharged in a short time after the completion of charging.

The present invention has been made in view of the above circumstances, and provides a vehicle generator control device capable of preventing insufficient charging at the time of deterioration without overloading a battery in a normal state. It is intended for.

[Means for solving the problem]

The generator control device for a vehicle according to the present invention is a generator control device that starts power generation when a battery voltage of the vehicle falls below a reference voltage, wherein the generator control device includes a deterioration state detection unit that detects a deterioration state of the battery. Reference voltage control means is provided for increasing a reference voltage of the generator, which is compared with a battery voltage based on an output of the detection means, in accordance with a state of deterioration of the battery.

The deterioration state detecting means for detecting the deterioration state of the battery is not particularly limited, and includes means for detecting the deterioration state based on the accumulated discharge time of the battery, means for detecting the deterioration state based on the accumulated charge time of the battery, and methods for detecting the deterioration state of the battery. , The deterioration state is detected based on the accumulated charge amount of the battery, the deterioration state is detected based on the accumulated traveling distance of the vehicle, and the like.

Preferably, the deterioration state detecting means is configured to be manually or automatically reset when the battery is replaced.

The control characteristic of the reference voltage control means may be such that the reference voltage is gradually increased from the time when the battery is mounted, and the reference voltage is kept constant while the deterioration of the battery hardly progresses. May be configured to gradually increase the reference voltage from the time when the operation has progressed to some extent.
As a control characteristic of the reference voltage control means, it is preferable to set an upper limit for the increase of the reference voltage so as not to overload the battery.

[Action]

In the generator control apparatus for a vehicle according to the present invention, when the deterioration state of the battery progresses and the deterioration state is detected by the deterioration state detecting means, the reference voltage of the generator is changed by the reference voltage control means to the deterioration state of the battery. Therefore, charging is performed at a relatively high voltage according to the state of deterioration of the battery. Therefore, when the deterioration is not progressing, the charging voltage is kept low to prevent the battery from being overloaded, and when it becomes difficult to sufficiently charge the battery, the charging voltage is increased to increase the charging amount and prevent insufficient charging. You can do it.

〔The invention's effect〕

As described above, according to the vehicle generator control device of the present invention, the deterioration state detecting means for detecting the deterioration state of the battery is provided, and the battery voltage is compared with the battery voltage based on the output of the deterioration state detecting means. Since the reference voltage of the generator is controlled to be increased in accordance with the state of deterioration of the battery, while the degree of deterioration of the battery is low, the charging voltage can be reduced to prevent the battery from being overloaded, while the degree of deterioration of the battery can be prevented. When the battery charge becomes high, the charge voltage can be increased to increase the charge amount, and the effect of increasing the discharge time after the completion of charging of the battery having a high degree of deterioration can be obtained.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows the overall configuration of a vehicle generator and its control device according to an embodiment of the present invention. The alternator 1 linked to the crankshaft of the engine E has five terminals BL, L. The terminal B and the terminal S are directly connected to the positive terminal (+ terminal) of the battery 2 and the terminal L
Is connected to a positive terminal of the battery 2 via a warning lamp relay 3, a key switch 4 and a fuse 5,
The terminal R is connected to the plus terminal of the battery 2 via the key switch 4 and the fuse 5 bypassing the warning lamp relay 3, and the terminal C is connected to the output terminal Vc of the controller 6.

As shown in FIG. 2, inside the alternator 1, a fixed field coil 7, three Y-type rotor coils 8, and a rectifier circuit 9 connected to the rotor coils 8 are provided. By rotating the rotor coil 8 with the field coil 7 energized, the output terminal of the rectifier circuit 9 is
For example, a power generation voltage of 16 to 17 volts can be obtained in 9a and 9b.

An output terminal of the rectifier circuit 9 is connected to one end of the field coil 7.
The positive terminal of the battery 2 is connected via a fuse 5, a key switch 4, a warning lamp relay 3 and a terminal L. The other end of the field coil 7 is grounded to the body via a voltage regulator 10 built in the alternator 1.

The voltage regulator 10 has one comparator 11
The voltage-dividing points of the voltage-dividing resistors R1 and R2 connected to the terminal S are connected to the negative-phase input terminal of the comparator 11, and the output terminal 6a of the controller 6 is connected to its positive-phase input terminal.
Are connected via a terminal C. The voltage regulator 10 includes a pre-stage transistor Q1 having a base connected to the output terminal of the comparator 11, and a grounded emitter post-stage transistor Q2 having a base connected to the emitter of the pre-stage transistor Q1. The base of the preceding transistor Q1 is connected to a terminal R via an adjustment resistor R3 and a forward connection diode D1, and the collectors of the preceding and succeeding transistors Q1 and Q2 are commonly connected to the other end of the field coil 7. I have. In addition, both transistors Q1
The collector of Q2 is a diode D2 for backflow prevention and an adjustment resistor
It is connected to the anode of the forward connection diode D1 via R4. An output terminal 9b of the rectifier circuit 9, an end of the field coil 7, and a terminal L are commonly connected to a connection point between the diode D2 for preventing backflow and the adjustment resistor R4.

In addition to the output terminal 6a, the controller 6 has a backup power input terminal 6b directly connected to the positive terminal of the battery 2, a power input terminal 6c connected to the positive terminal of the battery 2 via the key switch 4, and a ground. And a terminal G. Inside the controller 6, a power supply monitor comprising a CPU (central processing unit) 12 and a reset signal generator commonly connected via a constant voltage circuit 19 for outputting a constant voltage of +5 V to the backup power supply input terminal 6b. The counter 14 is reset each time the battery 13 and the battery 2 are replaced and counts the elapsed time during the key switch 4 ON, the D / A converter 15 connected to the output terminal 6a, and the battery 2 is charged. ROM 16 (read only memory) storing a charge control program and a memory map for setting a power generation operation reference voltage, RAM 17 (random access memory) storing various calculation results, and a backup power input terminal 6c The constant voltage supplied to the CPU 12, the counter 14, the D / A converter 15, the ROM 16 and the RAM 17 by converting the power supply voltage supplied from the battery 2 or the alternator 1 to a constant voltage of +5 V And a circuit 18.

The power supply monitor 13 is configured to output a reset signal RS for resetting the counter 14 to the counter 14 every time a new battery 2 is connected after the backup power supply is once cut off by removing the battery 2. ing.

The CPU 12 operates according to the charge control program read out from the ROM 16 at the same time when the key switch 4 is turned on. As shown in the flowchart of FIG. The count-up is started (S1), and the count number counted up by the counter 14 is read from the counter 14 every time the clock signal CL is input from the CPU 12 (S2), and the charging voltage corresponding to the count number is read from the ROM 16. Calculated based on the memory map for power generation operation reference voltage setting,
The charge voltage is multiplied by the voltage dividing ratio of the voltage dividing resistor to calculate a power generation operation reference voltage Vc (S3).
(S4), and the D / A converter 15 D / A converts the reference voltage Vc
Is output from the output terminal 6a to the comparator 11 of the voltage regulator 10, and then the steps S2 to S4 are repeated.

After the counter 14 starts counting up, the counter 14 continues the counting operation based on the clock signal CL input from the CPU 12 until the key switch 4 is turned off. When the key switch 4 is turned off, the counter 14 starts counting. The above control is stopped while the count number remains unchanged. Next, when the key switch 4 is turned on, unless the battery is replaced, the count number is accumulated in the previous count number.

However, if the battery 2 is replaced and a new battery 2 is mounted while the key switch 4 is OFF, the power supply monitor 13 detects this and outputs a reset signal RS to the counter 14,
The counter 14 is reset. Therefore, after the next key switch 4 is turned on, the counter 14 starts counting from zero again. In this way, the accumulated operation time of the key switch 4ON after the replacement of the battery 2 is counted.

The power generation operation reference voltage setting memory map stored in the ROM 16 pre-sets the relationship between the charging voltage and the accumulated operation time for obtaining the power generation operation reference voltage Vc, as shown in FIG. 4, for example. In addition, the charging voltage is set to a constant voltage, for example, 14 volts during a period from the start of counting to a predetermined cumulative operation time, for example, several hundred hours, and then gradually increased as the count number increases. ,
After a predetermined period from the start of counting, for example, a period of one thousand and several hundred hours, the charging voltage reaches a predetermined upper limit value, for example, 15 volts, and thereafter, in order to prevent the battery from being overheated due to overcharging. The charging voltage is set to be maintained at a certain upper limit.

The memory map for power generation operation reference voltage setting can be variously set, for example, for a cold region or for a cold season, the power generation operation reference voltage Vc is set to a higher value, or one considering a special natural environment such as a desert. It is possible to store a plurality of different power generation operation reference voltage setting memory maps in the ROM 17 as memories.

In the above configuration, when the key switch 4 is turned on and the engine E is started, a voltage is applied from the battery 2 to the base of the pre-stage transistor Q1 via the terminal R and the adjustment resistor R3, and the pre-stage transistor Q1 is turned on. become. On the other hand, a battery voltage is applied from the battery 2 to one end of the field coil 7 via the terminal L, and this battery voltage is applied to the rear transistor Q2 via the front transistor Q1.
As a result, the latter transistor Q2 is turned on, and the other end of the field coil 7 is connected to the latter transistor Q2.
, The field coil 7 becomes conductive, and a current having a voltage of 16 to 17 volts is output from the output terminals 9 a and 9 b of the rectifier circuit 9 by the induction power generation of the rotor coil 8. When the alternator 1 starts power generation, the voltage at the output terminal 9b of the rectifier circuit 9 is applied to the base of the former transistor Q1 via the adjustment resistors R4 and R3, so that the latter transistor Q2 is turned on and the output terminal of the rectifier circuit 9 is turned on. 9b, a field current is supplied to the field coil 7 and power generation is continued without receiving a current supply from the battery 2;
Instead, the alternator 1 functions as a power supply. Further, a voltage is applied from the output terminal 9a of the rectifier circuit 9 to the plus terminal of the battery 2 via the terminal B by the power generation of the alternator 1, and the battery 2 is charged.

On the other hand, by turning the key switch 4 on,
The CPU 12 of the controller 6 is started, and the charging voltage and the power generation operation reference voltage Vc corresponding to the accumulated operation time after the replacement of the battery 2 are calculated as described above.
The power generation operation reference voltage Vc obtained by the A conversion is output to the comparator 11 of the voltage regulator 10. When the partial pressure of the battery 2 falls below the power generation operation reference voltage Vc, the output of the comparator 11 becomes an “H” level signal,
The energization of the field coil 7 is maintained, and the charging of the battery 2 is continued.

When the partial voltage of the battery 2 is increased to the power generation operation reference voltage Vc or more, the potential of the output terminal of the comparator 11 becomes “L” level, the former transistor Q1 becomes nonconductive, and the latter transistor Q2 becomes nonconductive. Then, the field current is cut off, the power generation of the alternator 1 is stopped, and the charging of the battery is completed.

As described above, the power generation operation reference voltage Vc output from the controller 6 is constant when the cumulative operation time of the key switch 4ON after battery replacement is within a predetermined time, but thereafter, the predetermined upper limit value Until the cumulative operating time after battery replacement increases. That is, if the accumulated operation time after battery replacement is equal to or longer than a predetermined time, the charge amount is gradually increased,
The battery 2 that is difficult to be charged due to deterioration can be sufficiently charged and the discharge time can be lengthened. After the power generation operation reference voltage Vc reaches a predetermined upper limit, the power generation operation reference voltage Vc is fixed to the upper limit value in order to prevent heat generation due to overcharging of the battery 2.

Note that a part of the controller 6 may be modified as shown in FIG.

That is, the power supply monitor 13A composed of a flip-flop circuit
And a power monitor 13 when the battery 2 is replaced.
A +5 V rechargeable secondary battery 20 for backing up the A and RAM 17 is provided, and the output terminal of the constant voltage circuit 19 is connected to the power supply monitor 13A, the secondary battery 20 and the R via the diode 21 connected in the forward direction.
Connect to AM17, and connect the output terminal of power supply monitor 13A to CPU12.

In the above configuration, when the battery 2 is removed, the power supply monitor 13A is backed up by the secondary battery 20, and its operation is maintained. Since the output signal of the power supply monitor 13A is inverted each time the signal level of the input terminal of the power supply monitor 13A rises from the "L" level to the "H" level due to the replacement of the battery 2, the level of this output signal is If the information is stored using a flag, replacement of the battery 2 can be detected.

The charge control routine in this case is as shown in FIG.

Control is started when the key switch is turned on. First, the output signal of the power supply monitor 13A is read, and this output signal is
It is determined whether or not the battery 2 has been replaced based on the data stored with the flag (S1). Next, when the battery 2 has been replaced, the counter 14 is reset (S2). Alternatively, when the battery 2 is not replaced, the count-up by the counter 14 is started (S3), and the steps S4 to S6 are repeated in the same manner as described above.

When the whole controller 6 is backed up by the secondary battery 20, RA is used instead of the counter 14.
A soft counter provided in M17 may be used, and the power supply monitors 13 and 13A may be omitted, a counter reset command switch may be provided, and the counter 14 may be reset by operating the switch. In this case, the counter 14 can be reset only when the battery 2 is replaced with a new battery 2.

In the above embodiment, the deterioration state of the battery 2 is detected based on the accumulated operation time after the replacement of the battery 2. However, the state where the battery 2 is charged to a predetermined voltage is changed to a predetermined electric load (for example, The deterioration state of the battery 2 may be detected from a battery discharge current, a battery voltage or a battery voltage drop rate when the starter is operated for a predetermined time. The deterioration state of the battery 2 may be detected based on the consumed amount of electricity and the voltage drop value, or the accumulated state of the battery 2 may be determined by calculating the accumulated discharge time and the accumulated charge time after the battery 2 is replaced. The battery 2 may be configured to detect the deterioration state of the battery 2 by calculating the accumulated discharge amount or the accumulated charge amount after the battery 2 is replaced. May be configured to detect the deterioration state of the battery 2 yield a cumulative running distance of Teri 2 after the replacement.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention. FIG. 1 is an overall configuration diagram of a power generation device and a generator control device of an automobile, FIG. 2 is a circuit diagram of a control system thereof, and FIG. FIG. 4 is a flowchart of a charge control routine, FIG. 4 is a charge voltage control characteristic diagram for obtaining a power generation operation reference voltage, FIG. 5 is a configuration diagram of a controller according to a modification, and FIG. 6 is a flowchart of a charge control routine according to the first embodiment. 1 ... alternator, 2 ... battery, 6 ... controller.

Claims (1)

(57) [Claims] 1. A generator control device for starting power generation when a battery voltage of a vehicle falls below a reference voltage, further comprising a deterioration state detecting means for detecting a deterioration state of the battery, and based on an output of the deterioration state detecting means. A generator control device for a vehicle, comprising: a reference voltage control unit that increases a reference voltage of the generator, which is compared with a battery voltage, in accordance with a state of deterioration of the battery.