JPH10285821A - Voltage controller of ac generator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the charging performance of a battery by holding the battery voltage as high level as possible within an allowable range from an overcharging preventive point of view. SOLUTION: When the average value of the battery voltage in a given period of time (3-30 minutes) including a given increase and decrease in the number of rotations of an engine exceeds a given level V1 (step 108), the adjustment voltage is lowered (step 138) to lower the battery voltage. On the other hand, when the average value of the battery voltage comes below the predetermined level V2 (step 112), the adjustment voltage is raised (step 116) to raise the battery voltage. Since the adjustment voltage is switched, based on the average value of the battery voltage or the integrated detected value of the battery voltage, the average value of the battery voltage does not change so frequently along with a short-time fluctuation (increase and decrease) of the battery voltage caused by the change in the number of rotations of the engine as in the conventional method, thereby stably keeping the average value near a specified level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage control apparatus for a vehicle alternator, and more particularly to a voltage control apparatus for a vehicle alternator that increases the amount of battery charge while avoiding overcharging of the battery.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. Hei 4-275035 discloses that in a voltage control device for an engine-driven vehicle alternator (alternator), when the battery voltage exceeds a lower regulated voltage, power generation is stopped and the battery voltage is reduced. Control is performed so that the battery voltage matches the low-side adjustment voltage while the power generation is performed only below the low-side adjustment voltage, and when the battery voltage falls below a predetermined determination level, the battery is switched to the high-side adjustment voltage, and the battery is switched to the high-side adjustment voltage. It has been proposed that when the voltage increases to the higher adjustment voltage, the adjustment voltage is returned to the lower adjustment voltage.

Further, in this publication, a high-frequency component of 750 Hz or more (also referred to as alter-ripple component) superimposed on the battery voltage because the battery is charged with the three-phase full-wave rectified voltage is compared with the regulated voltage before the comparison. It has also been proposed to perform the power generation control based on the average value of the battery voltage in order to eliminate the power generation.

[0004]

In the regulated voltage switching type voltage control device disclosed in the above publication, the regulated voltage is set to a higher value only after the battery voltage has fallen below the judgment level and thereafter becomes higher. In the period until the adjustment voltage on the
During the other periods, the adjustment voltage is kept at a lower value.
On the other hand, the battery voltage is related to the state of charge of the battery, that is, the accumulated charge / discharge current value of the battery, and the charge current to the battery (output current of the generator) is related to the engine speed.

Therefore, when the vehicle is traveling in an urban area where the idle state and the traveling state are frequently repeated, the engine speed is low on average, the charging current (battery voltage) is low on average, and even if the battery voltage is low. Even if the adjustment voltage drops below the determination level and is switched to a higher value, the value returns to the lower value again in a short period of time, and as a result, the battery voltage sometimes exceeds the lower value, but is generally low. In this case, the charging voltage of the battery becomes lower than the adjustment voltage on the side of the battery, so that the charge amount of the battery is reduced. In particular, when the current consumption of the electric load is large, the charging may be insufficient.

Of course, if the judgment level for switching the adjustment voltage or the adjustment voltage on the lower side is set high beforehand, the charge amount of the battery can be improved. Is performed, the average battery voltage becomes high, and an overcharge state (a state in which an overcharge current that causes the decomposition of the electrolyte flows into the battery) occurs in the battery. A drop occurs.

That is, in the conventional regulated voltage switching type voltage control device, the regulated voltage is switched only based on the immediate change of the battery voltage irrespective of the external conditions of the vehicle power generation device such as the vehicle running condition. Therefore, the original purpose of the switching of the regulated voltage, that is, the overcharging of the battery (specifically, the liquid reduction) is suppressed to an allowable level or less and the insufficient charging of the battery is prevented, cannot be sufficiently achieved.

[0008] For example, in the above-described conventional voltage control device of the regulated voltage switching type, the regulated voltage is immediately switched according to the result of comparison between the battery voltage and the judgment level, so that the vehicle can be used for city value driving or periodic intermittent electric load. When the battery voltage repeatedly increases and decreases in a relatively short time due to the periodic fluctuation of the operating condition, the vehicle operating condition changes (for example, a decrease in the engine speed) after the adjustment voltage is lowered due to the temporary increase of the battery voltage. The battery charge current decreases, causing a rapid decrease in the battery charge amount, or conversely, a change in vehicle operating conditions (for example, an increase in engine speed) after the adjustment voltage is increased due to a temporary decrease in the battery voltage. There is also a problem that the battery charging current increases and an overcharging current flows to the battery.

Further, in the above-described conventional voltage control apparatus of the switching type, the adjustment voltage is frequently switched for the above-mentioned reason, which causes a frequent sudden change in the engine load, which is not preferable from the viewpoint of engine control. SUMMARY OF THE INVENTION It is an object of the present invention to detect a cumulative detection value of a battery and change the adjustment voltage based on the detection value to maintain a good state of the battery.

Another object of the present invention is to improve the charging performance by maintaining the battery voltage as high as possible within a range allowable from the viewpoint of suppressing overcharge.

[0011]

According to a first aspect of the present invention, the output of the alternator is adjusted according to a predetermined regulated voltage, and when the battery voltage exceeds the regulated voltage. Since the control for stopping the power generation is performed, the voltage of the battery is controlled to a value lower than the adjustment voltage with the adjustment voltage as an upper limit.

In particular, in this device, the integrated detection value within a predetermined observation period, that is, the interval at which the rotation speed of the internal combustion engine increases or decreases in accordance with the running and stopping of the vehicle, and the value of the predetermined electric load device which operates intermittently. The adjustment voltage is changed by a value corresponding to the integrated amount of the battery voltage within a predetermined observation period set longer than at least one of the operation intervals.

For example, when the integrated detection value exceeds a predetermined level, the adjustment voltage is reduced to lower the battery voltage, and when the average state of charge is lower than the predetermined level, the adjustment voltage is increased to increase the battery voltage. That is, since the switching control of the adjustment voltage is performed based on the integrated detection value, the average value of the battery voltage is short-term variation (eg, short-term variation of the battery voltage due to engine speed variation and increase / decrease in power consumption of the vehicle electric load) as in the related art. This does not frequently fluctuate in conjunction with (increase / decrease), and is stably maintained near the predetermined value.

More specifically, the battery voltage charged by the ordinary vehicular alternator fluctuates in accordance with the above-mentioned vehicular operating state (engine speed and driving state of the vehicular electric load). . For example, at the time of idling or the like, an electric load such as an electric fan of a radiator may be turned on / off at a cycle of several tens seconds to several minutes. Also,
In a general urban area running of a vehicle represented by the so-called 10 mode, an idle state and a running state are often alternated in a period of several tens of seconds to several minutes. It is not uncommon for it to increase or decrease in a few minute cycle.

Therefore, in such a case, as in the prior art described above, immediately after the battery voltage rises due to the turning off of the electric load for the vehicle or the increase in the engine speed while traveling in a city area, the adjustment voltage is immediately reduced to lower the battery voltage. If this is done, the battery voltage tends to further decrease due to the turning on of the above-described electric load for the vehicle or the decrease in the engine speed while traveling in a city area, and eventually the average overcharge amount (for example, specifically, Although the amount of the electrolyte is sufficiently low, the integrated amount of the battery voltage (for example, the average battery charging performance or the charged amount of the battery) during this period in which the charging performance of the battery is strongly required is greatly increased. There is a problem that it is lowered.

According to the device of the present invention, since the adjustment voltage is changed by the integrated detection value, the insufficient charge of the battery is suppressed while the amount of overcharge of the battery and the amount of decrease of the battery due to the battery are suppressed to an allowable level or less. Can be prevented. For example, in the device according to the present invention, the adjustment voltage is controlled so that the integrated detection value is maintained within an allowable level range of the charge amount (liquid reduction amount), and preferably as high as possible within the range.
In this way, even if the battery voltage temporarily rises, the integrated amount of the battery voltage falls within the allowable overcharge range, and as a result, the vehicle running state and the driving of the vehicle electric load are reduced. Regardless of the increase or decrease of the battery voltage depending on the situation, as described above, it is possible to prevent the battery from being insufficiently charged while suppressing the overcharge amount of the battery (the amount of liquid reduction) to an allowable level or less.

Further, in the device according to the present invention, since the adjustment voltage is not frequently switched, frequent fluctuations of the generator load as viewed from the engine can be reduced to prevent the driving feeling from deteriorating. Also, frequent sudden changes in the battery voltage (which may adversely affect the vehicle electrical load used) can be suppressed. According to a second aspect of the present invention, the observation period is set to be longer than a shortest intermittent cycle of an electric radiator fan attached to the internal combustion engine. The electric radiator fan is not started by the drive control circuit until a predetermined shortest intermittent cycle elapses after being started.
This is to prevent a large starting current from frequently flowing to the electric radiator fan as in the case of normal motor drive control.

According to this configuration, since the observation period is set to be equal to or longer than the intermittent cycle of the electric radiator fan, the adjustment voltage does not change frequently due to a change in the battery voltage due to the intermittent operation of the electric radiator fan. It is possible to prevent problems such as frequent changes in the generated voltage. Also, the above-mentioned overcharge failure (early liquid shortage etc.)
, The battery voltage integrated amount (that is, battery charging performance) can be kept high.

This configuration will be described in more detail. The electric radiator fan attached to the vehicular internal combustion engine may be frequently intermittently driven in an operation mode such as running in an urban area during heavy traffic. This is because after operating the electric radiator fan and the cooling water temperature falls below a predetermined value level,
This is because it takes time for the cooling water temperature to rise again to the starting temperature of the electric radiator fan, and thus the difference between the starting temperature and the stopping temperature of the electric radiator fan is caused by frequent starting of the electric radiator fan. This is to prevent a large starting current from frequently flowing and causing a motor burnout accident. Such a hysteresis operation is common in normal motor control.In addition to performing the hysteresis operation with a difference in the temperature input, an interlock circuit is provided to prevent the motor from restarting for a predetermined time after the motor stops. May be realized. Therefore, in such a drive mode of the electric radiator fan, the intermittent cycle is gradually shortened as the coolant temperature rises, and when the predetermined shortest cycle is reached, the operation shifts to the continuous operation.

If the electric radiator fan is frequently switched on and off in a traffic congested city area or the like, the battery voltage fluctuates accordingly. In the regulator of the regulated voltage switching type that switches Vref, the regulated voltage Vref fluctuates frequently, and thus there is a problem that the battery voltage further fluctuates.

In particular, when the vehicle is running at a low speed in which the electric radiator fan is frequently interrupted, the value of the generated current that can be output from the generator is small, so that the fluctuation of the battery voltage is further increased. That is, the electric radiator fan, which is frequently interrupted during low-speed traveling with a small amount of cooling air, has a problem that the tendency of the battery voltage to change frequently is particularly high as compared with various types of vehicle electric loads.

Therefore, in this configuration, an integrated detection value (a value corresponding to the battery voltage integrated amount) in the observation period set at least longer than the shortest intermittent cycle of the electric radiator fan is detected, and the integrated detection value is determined. Adjustment voltage V based on
Since the ref is changed, the frequent switching of the electric radiator fan causes the adjustment voltage Vref to be frequently switched, thereby causing the battery voltage to fluctuate frequently and the engine load to fluctuate frequently.
This can be realized without employing a means of completely stopping the change of the adjustment voltage Vref.

According to a third aspect of the present invention, in the apparatus of the first or second aspect, the observation period is further set to 3 to 30 minutes. Note that even when the observation period is set to 3 to 30 minutes, the adjustment voltage can be changed in a shorter cycle. For example, the adjustment voltage may be changed every minute by a moving average value of a plurality of data sampled at a fixed sampling interval during the observation period.

[0024] Frequent intermittent changes such as an increase or decrease in engine speed (repetition of stoppage of a signal and subsequent running) or an electric radiator fan, etc., which frequently occur in the above-mentioned urban driving, are as follows.
Since it often occurs at intervals of several tens of seconds or more and less than 30 minutes, by setting the predetermined period to 3 to 30 minutes,
Frequent fluctuations in the adjustment voltage due to short-period fluctuations in the battery voltage due to an increase or decrease in the engine speed or intermittent operation of the electric radiator fan in the city area can be prevented.

If the predetermined period is less than 3 minutes, the adjustment voltage is changed in response to the change in the battery voltage, so that the effect of improving the charging performance is diminished. In frequent vehicles,
Since the adjustment voltage often becomes the initial set value, if the adjustment voltage is at a high level, an overcharge failure is likely to occur. Conversely, if the adjustment voltage is at a low level, the charging performance cannot be improved.

According to a fourth aspect of the present invention, in the apparatus according to any one of the first to third aspects, the integrated detection value (a value corresponding to the integrated amount of the battery voltage) exceeds a predetermined first determination value. In this case, the adjustment voltage is reduced, and when the integrated detection value is lower than the second determination value lower than the first determination value, the adjustment voltage is increased. Therefore, hunting is suppressed to prevent frequent changes in the adjustment voltage. Thus, the battery voltage can be stabilized.

According to a fifth aspect of the present invention, in the device according to the first to fourth aspects, the adjustment voltage changing means further comprises means for limiting the adjustment voltage to a predetermined maximum rate of change or less, ie, hardware or software. Including wear. According to this configuration, the adjustment voltage is changed by using the integrated detection value, and the frequent change with respect to the instantaneous fluctuation of the battery voltage is restricted by the means according to claim 1, Even if it is changed, since the regulation of the adjustment voltage change rate is further regulated to regulate the change speed of the adjustment voltage,
Even if the integrated detection value changes significantly in a short period of time, it is possible to prevent a sudden change in the adjustment voltage, thereby achieving effects such as preventing a sudden change in the battery voltage.

More specifically, the integrated detection value calculated from the battery voltage in the above-described predetermined observation period (a value corresponding to the integrated amount of the battery voltage) is the adjustment voltage of the adjustment voltage due to the fluctuation of the battery voltage in a cycle shorter than this observation period. This is effective in suppressing fluctuation. However, even when the period is longer than the observation period, if the battery voltage changes significantly in a relatively short time, the integrated detection value calculated from the battery voltage value in the observation period may also fluctuate greatly. In order to improve this problem, it is conceivable to further extend the observation period, that is, to further remove the high-frequency component of the input battery voltage signal. However, extending the observation period unnecessarily in this way is a problem that the adjustment voltage is not reduced even though the battery voltage is long and excessive, and the adjustment is performed even if the battery voltage is long and too low. This causes a problem that the voltage is not raised.

According to the present invention, it is possible to prevent a change in the adjustment voltage when the battery voltage greatly changes in a relatively short time and to prevent a sudden change in the battery voltage while avoiding such a problem. it can. That is, even if the observation period is not set unnecessarily long, by limiting the rate of change of the adjustment voltage to a certain value or less, it is possible to prevent a sudden change in the adjustment voltage and to suppress an undesirable sudden change in the battery voltage. .

According to a sixth aspect of the present invention, in the device of the fourth aspect, the battery voltage or the integrated detection value (a value corresponding to the integrated amount of the battery voltage) is a third determination value (deep discharge state). In this case, the adjustment voltage is increased at a predetermined rapid increase rate. More specifically, when the adjustment voltage is increased or decreased in accordance with the integrated detection value, even if the battery voltage is extremely reduced, the increase in the charging current becomes slow, which causes a problem that the battery is insufficiently charged. Occurs.

Therefore, according to the present invention, when the battery voltage or the integrated detection value is lower than the third determination value (a determination value for detecting that the battery is deeply discharged), the adjustment voltage is increased at a predetermined rapid rise rate. And adjusting the adjustment voltage to the first,
When changing based on the second determination value, the change rate is set to be smaller than the absolute value of the rapid rise rate. With this configuration, the battery can be rapidly charged at the time of deep discharge of the battery, so that a situation in which the battery is insufficiently charged can be avoided.

According to a seventh aspect of the present invention, in the device of the fifth or sixth aspect, the minimum value of the rate of change of the adjustment voltage changed in accordance with the integrated detection value (a value corresponding to the integrated amount of the battery voltage). Is set to 0.01 V / min or more. With this configuration, it is possible to prevent a problem such as overdischarging or overcharging (liquid reduction) due to too slow follow-up of the adjustment voltage change with respect to the average change in the battery voltage.

According to the means of claim 8, in the apparatus of claim 5 or 6, the rate of change of the adjustment voltage to be changed in accordance with the integrated detection value (a value corresponding to the integrated amount of battery voltage) is set to 0. Regulate to less than 1V / min. According to experimental results under various driving conditions (vehicle speed and electric load), by regulating the rate of change of the regulated voltage to less than 0.1 V / min,
Even if the cumulative detection value fluctuates frequently or suddenly due to a short-term change in engine speed or intermittent electrical load, prevent overcharging and undercharging while preventing complicated and large fluctuations in the regulated voltage due to the fluctuation. Can be. As a result, it is possible to reduce the adverse effect on the electric load represented by the fluctuation of the lamp brightness.

According to a ninth aspect of the present invention, in the device according to any one of the first to eighth aspects, when the integrated detection value (a value corresponding to the integrated amount of the battery voltage) falls below a predetermined value, the adjustment voltage is first set. Is increased to a predetermined value, and when the integrated detection value is still lower than the predetermined value, the idle speed is increased, so that fuel efficiency can be improved without insufficiency of charging and frequent changes in the idle speed can be prevented. Thus, the driving feeling can be improved.

According to a tenth aspect of the present invention, in the apparatus according to any one of the fourth to ninth aspects, further, when the integrated detection value (a value corresponding to the integrated amount of the battery voltage) exceeds a predetermined value, the idle rotation is started. Since the number is reduced and the adjustment voltage is further reduced to the predetermined value when the integrated detection value still exceeds the predetermined value, fuel efficiency can be improved without insufficiency of charging. According to the means described in claim 11, in the device according to any one of claims 1 to 10, further, when the predetermined deep discharge state of the battery lasts for a predetermined set time or more, the regulation of the adjustment voltage is reduced. In a situation where the battery charge shortage is serious, even if the integrated detection value (a value corresponding to the battery voltage integrated amount) is temporarily determined to be overcharged, the adjustment voltage is not reduced, and the battery charging performance is not reduced. Can be kept high. More specifically, even after such a deep discharge, if the engine speed becomes high, a large charging current flows into the battery, and as a result, a large battery voltage is detected.

According to this means, after such a deep discharge, for example, until a certain fixed period or a point in time when the overcharge can be considered to be not negligible (for example, when the accumulated value of the overcharge current becomes a certain value or more). Even if the integrated detection value is determined to be in an overcharged state, the adjustment voltage is prevented from being reduced for a certain period of time, so that if the battery discharge continues and the battery capacity is greatly reduced, the battery charging performance will be improved. Since the battery charge rate is quickly maintained and improved, the battery charge rate can be improved.

According to a twelfth aspect of the present invention, in the device according to any one of the first to eleventh aspects, the voltage adjusting means, the detecting means for detecting an integrated detection value, and the adjusting voltage changing means are all mounted on the generator. Therefore, the configuration can be simplified because an external control device is unnecessary. According to a thirteenth aspect of the present invention, in the device according to any one of the first to eleventh aspects, a detecting means for detecting an integrated detection value and an adjusting voltage changing means are provided outside the generator, and the voltage adjustment is performed. Since the adjustment voltage set by the means is transmitted as an adjustment voltage signal to the voltage adjustment means attached to the generator, a battery voltage detection line is unnecessary for the control device on the generator side, so that a simple configuration can be achieved.

According to the means of claim 14, in the apparatus of any of claims 1 to 11, the change of the adjustment voltage is interrupted for a predetermined time after the start of the internal combustion engine. The effect can be achieved. That is, for several minutes immediately after the start (for example, 10 to 30 minutes), even if the integrated detection value (a value corresponding to the integrated amount of battery voltage) is higher than the predetermined value, the adjustment voltage does not decrease. It is possible to quickly charge the dark current discharge and the discharge caused by the starter start, and to maintain the charge of the battery satisfactorily even in the case of repeated running for a short time.

According to a fifteenth aspect of the present invention, in the device according to any one of the fourth to fourteenth aspects, the determination value is further shifted based on the detected battery temperature or a parameter that changes according to the detected temperature. Even if the temperature environment is different, overcharging can be suppressed well. That is, since the relationship between the charge voltage of the battery and the amount of overcharge is greatly affected by the temperature, by changing the determination value in consideration of the battery temperature characteristic with respect to the overcharge level, even if the operating temperature environment differs, Charging can be prevented well.

For example, when the battery temperature is low, the battery capacity becomes small, so that insufficient charging is likely to occur. Therefore, by increasing the adjustment value Vref by increasing the determination value at a low temperature, insufficient charging can be suppressed. According to the means of claim 16, the apparatus of claim 15, further utilizing the fact that the temperature of the voltage adjusting means has an approximately positive correlation with the battery temperature,
The determination value is shifted based on the temperature of the voltage adjusting means. With this configuration, a dedicated sensor for detecting the temperature of the battery is not required, and a simple configuration can be achieved.

According to the seventeenth aspect, in accordance with the fifteenth aspect,
In the described device, the determination value is further shifted based on the elapsed time after the start of the internal combustion engine by utilizing that the elapsed time after the start of the internal combustion engine is approximately positively correlated with the battery temperature. That is, after the engine starts, the battery temperature
It gradually rises due to heating from the engine. Therefore, if the determination value is shifted based on the elapsed time after the start, a dedicated sensor for detecting the temperature of the battery is not required, and the configuration can be simplified.

According to the means of the eighteenth aspect, the integrated detection value (the value corresponding to the integrated amount of the battery voltage) is detected by the high-range reduced battery voltage, so that the apparatus has a simple configuration. The average charging performance of the battery can be reliably detected. According to the means of the nineteenth aspect, in the apparatus of the eighteenth aspect, an integrated detection value (a value corresponding to the integrated amount of the battery voltage) is detected based on the average value of the battery voltage within the predetermined period.
The average charging performance of the battery can be reliably detected with a simple configuration.

According to a twentieth aspect, in the device according to the first aspect, in particular, the integrated detection value (corresponding to the integrated amount of the battery voltage) is determined by a ratio of a period in which the battery voltage (voltage) in the predetermined period exceeds a predetermined value. ), It is possible to reliably detect the average charging performance of the battery with a simple configuration. According to the means of the present invention, the integrated detection value (a value corresponding to the integrated amount of battery voltage) is obtained by the cumulative value of the overcharge current flowing into the battery during the predetermined period. The overcharge state is detected when the cumulative value of the overcharge current is greater than or equal to a predetermined set value, so that the average charge performance of the battery can be reliably detected with a simple configuration. Since the overcharge current accurately has a correlation with both the battery voltage and the battery temperature, the battery temperature is also detected, and the overcharge current is calculated from a three-way map of the battery temperature, the battery voltage, and the overcharge current. It can also be detected.

[0044]

【Example】

(Embodiment 1) An example of a vehicle charging apparatus using a voltage control apparatus for a vehicle AC generator according to the present invention will be described with reference to the circuit diagram of FIG. The vehicle alternator 2 driven by the vehicle-mounted engine 1 includes a stator coil 9, a rectifier 10,
The stator coil 9 has an exciting coil 11, and generates an electric current by supplying an exciting current to the exciting coil 11. The generated voltage is rectified by the rectifier 10 and supplied to the battery 6 and the electric load (vehicle electric load) 7. .

Reference numeral 3 denotes an exciting current driving circuit for intermittently controlling the exciting current, 12 is a freewheel diode, 13 is an N-channel power MOS transistor for exciting current driving, 14 is a protection diode for protecting its gate electrode, and 15 is a gate. This is an input resistance for suppressing the input of a surge voltage to the electrode. The transistor 13 is intermittently driven by the control voltage input to the transistor 13 through the input resistor 15,
As a result, the exciting current supplied to the exciting coil 11 is controlled, whereby the generated voltage is controlled, and the charging current of the battery 6 is controlled. Since the configuration itself of the vehicle charging device described above is well known, further description is omitted.

The charge control circuit 4 includes resistors 20 and 21 forming a voltage dividing circuit for dividing the voltage of the battery 6 (battery voltage).
The divided voltage of the battery voltage (hereinafter, also simply referred to as the battery voltage) obtained from the connection point of the resistors 20 and 21 is input to the negative input terminal of the comparator 16 and A
A microcomputer 19 via a D converter 18
Is input to The output result calculated by the microcomputer 19 is output to the comparator 1 via the DA converter 17.
The comparator 16 compares the battery voltage with the adjusted voltage, outputs a low level when the battery voltage is high, turns off the transistor 13, and when the battery voltage is low, the comparator 16 compares the battery voltage with the adjusted voltage. The transistor 13 is turned on by outputting a high level, thereby controlling the exciting current.

The output result calculated by the microcomputer 19 is transmitted to the idle rotation control device 8 which is a part of the microcomputer for controlling the engine, and the idle rotation control device 8 controls the engine 1 based on the input signal.
Control the idle speed of the engine. Reference numeral 5 denotes a key switch, and a power supply voltage is applied to the microcomputer 19 when the key switch 5 is turned on.

Hereinafter, the operation of the microcomputer 19 for performing the adjustment voltage switching control, which is a feature of the present embodiment, will be described with reference to the flowcharts of FIGS.
In the first step 100, when a power supply voltage is applied to the microcomputer 19 by turning on the key switch 5, initialization is performed, the adjustment voltage and the idle speed are set to predetermined initial values, and a charging mode flag described later is set. Set to normal mode (level 0) and set time (control execution cycle)
Reset and start the timer that counts.
The set time is set to several tens of seconds in this embodiment.

FIG. 3 shows an interrupt routine which interrupts the main routine of FIG. 2 at one-second intervals.
b (step 200), and the average of the battery voltage values Vb read during the sampling period (predetermined period in this specification) for calculating the average value for the immediately preceding 3 to 30 minutes including the currently read battery voltage value Vb. The value Va−b is calculated and the contents of the average value storage memory are rewritten (step 2).
02), returning to the main routine.

Step 102 is a standby step for determining the execution period of the main routine for the count time of the built-in timer for counting the set time, and checks whether the built-in timer has reached the set time and waits until it reaches the set time. , The internal timer is reset / restarted (step 104). Next, the average value Va of the battery voltage
It is checked whether or not −b is larger than a predetermined overcharge state determination value V1 (step 108). If it is larger, it is regarded as an overcharge state (an overcharge state that cannot be ignored) and the process proceeds to step 130; Go to average value Va
It is checked whether or not −b is smaller than a predetermined undercharge determination value V2. If the value is smaller than the predetermined value, it is determined that the battery is undercharged, and the process proceeds to step 114. Otherwise, the process returns to step 102.

In step 114, it is checked whether or not the adjustment voltage Vref has reached a predetermined upper limit (here, 14V). If not, the adjustment voltage Vref is adjusted to a predetermined amount (for example, 0.5V) within a range not reaching 14V. ) (Step 116), otherwise set the idle speed to a predetermined high value or a predetermined amount (eg, 50 rpm) within the range where the idle speed reaches a predetermined maximum value.
m) (step 118).

Thereafter, it is checked whether or not all the three average values Va-b immediately before read in step 108 are smaller than the deep discharge determination value V3 (step 120). If not smaller, the process returns to step 102; 6
Is determined to be in a state of insufficient charge at present, the second timer is reset and then started (step 122), and the process proceeds to step 124.

In step 124, the charge mode flag is set to the charge recovery mode (level 1), and the adjustment voltage Vr
ef is set to the upper limit value Vrefu (here, 14 V), and the process returns to step 102. In this embodiment, V1 is 13.5 V, V2 is 13.0 V, and V3 is 1
It is set to 2.5V. Next, an operation when it is determined in step 108 that the average value Va-b is larger than V1, that is, when it is determined that the battery is in an overcharged state, will be described.

In this case, it is checked in step 130 whether the charge mode flag is the normal mode or the charge recovery mode. If it is the normal mode, the process proceeds to step 132, and if it is the charge recovery mode, the process proceeds to step 134. Note that the charge recovery mode is performed after the battery voltage has been reduced for a long time,
This is a charge control mode for performing strong battery charging, and is a charge control mode other than the normal mode.

In step 132, it is checked whether or not the idle speed read from the idle speed control device 8 is equal to or less than a predetermined minimum value. If not, the idle speed is reduced to the predetermined minimum value or reduced to the predetermined minimum value. It decreases by a predetermined amount within the range until it reaches (step 136). If the idling rotation has reached a predetermined minimum value, the adjustment voltage Vre
f is reduced by a predetermined amount within a range until reaching a predetermined lower limit value Vrefd (here, 13.2 V) (step 1).
38), returning to step 102;

If it is determined in step 130 that the charging mode flag is in the charging recovery mode, it is checked whether or not the second timer for determining the execution time of the charging recovery mode has expired (step 134). If so, the charging mode flag is returned to the normal mode in step 140, and the process returns to step 102.

In the above description, the correction of the idling speed has been described as an example in which the idling speed is determined to be insufficient and the raised idling speed is returned to a reference value when the idling speed is determined to be an overcharged state. Even if is the reference value, when it is determined that the battery is overcharged, the idling speed can be made lower than the reference value prior to the decrease in the adjustment voltage, and in this way, fuel efficiency can be improved. (Embodiment 2) Another control example will be described with reference to the flowcharts of FIGS.

This control routine is different from the control routine of FIGS. 2 and 3 in that step 204 is added and step 1 is added.
08 is changed to step 208. In step 204, the currently read battery voltage value Vb
Each battery voltage value Vb read in a sampling period (predetermined period referred to in this specification) for overcharge current integration for 3 to 30 minutes immediately before including in a built-in map, and each battery voltage value in this sampling period Overcharge current values respectively corresponding to Vb are searched from a built-in map, and the searched overcharge current values are accumulated to obtain an overcharge current integrated value I.
Calculate k and rewrite the contents of the memory that stores it.

In step 208, it is checked whether or not the obtained overcharge current integrated value Ik is larger than a predetermined overcharge state determination value I1, and if it is larger, it is regarded as an overcharge state (an overcharge state that cannot be ignored) and step 130 is performed. If not, the process proceeds to step 112 to check whether or not the average value Va-b is smaller than a predetermined insufficient charge determination value V2. In this way, there is an advantage that the overcharge state can be accurately determined as compared with the overcharge detection method of the first embodiment. (Embodiment 3) Another control example will be described with reference to the flowcharts of FIGS.

In this control routine, in the control routine of FIGS. 2 and 3, step 200 is changed to step 206, step 207 is added, step 108 is changed to step 308, and step 112 is changed to step 31.
2 in that step 120 is changed to step 313. In step 206, the battery voltage value Vb is compared with predetermined overcharge state determination values V1, undercharge state determination values V2, and deep discharge determination values V3. Further, at step 207, a time T1 at which the battery voltage Vb is greater than the overcharge state determination value V1 is measured, and similarly, a time T2 at which the battery voltage value Vb is smaller than a predetermined undercharge state determination value V2 is measured. In step 313, VB
It is determined that the state of <V3 has continued for the predetermined time Tth3 or more, and the state is a deep discharge state.

In step 308, the overcharge state time T1
Is larger than a predetermined overcharge state determination value Tth1. If it is larger, it is regarded as an overcharge state (an overcharge state that cannot be ignored), and the process proceeds to step 130. Otherwise, the process proceeds to step 312. In the next step 312, it is checked whether or not the insufficient charge time T2 is greater than a predetermined insufficient charge state determination value Tth2.
Return to 02.

In this way, it is not necessary to directly read the value of the battery voltage, but only to compare the battery voltage with each of the judgment values V1, V2, V3 using the comparator. An A / D converter and the like are not required as compared with the method, and the circuit configuration is simplified. FIGS. 8 to 10 show changes in the battery voltage when the control of the first embodiment is applied to various changes in the engine speed.

FIG. 8 shows a battery voltage in a mode in which the engine speed is increased from an idle speed to a predetermined high speed value in a cycle of about 5 minutes as a model for driving in an urban area.
FIG. 9 is a timing chart showing changes in the average value and the adjustment voltage. FIG. 9 shows a battery voltage, a mean value, and an adjustment voltage in a mode in which the engine speed increases for a long time after the engine speed increases as a suburban driving model. FIG. 10 is a timing chart showing changes in the battery voltage, its average value, and the adjustment voltage in a mode in which idle rotation continues for a long time.

As shown in each of the above-described embodiments, by detecting the long-term battery voltage integrated amount (integrated detection value referred to in the present invention), the long-time average overcharge amount in actual running can be reduced to a predetermined value. Therefore, even if the battery voltage frequently increases or decreases as shown in FIG. 6, the charging performance of the battery 6 can be improved without exacerbating the overcharge state.

In the above-described embodiment, a simple average value is used as a method of obtaining the integrated amount of battery voltage. However, as another example, the integrated amount of battery voltage may be obtained using a moving average value or a delay value. (Embodiment 4) Another embodiment will be described with reference to FIGS. However, the same components as those in the above embodiment are denoted by the same reference numerals.

This embodiment is different from the first embodiment shown in FIG. 1 in that the charge control circuit 4 does not use an A / D converter and a microcomputer. Thus, in this embodiment, the charging control circuit 4 in addition to the exciting current drive circuit 3 can be easily built in the generator 2, and the device configuration can be simplified. Hereinafter, the charge control circuit 4 which is a feature of this embodiment will be described.

In the charge control circuit 4, 20 and 21 are resistors, 23 to 25 and 30 are comparators, 26 is an overcharge time integrating circuit, 27 is an adjustment voltage setting circuit, 28 is an undercharging time integrating circuit, and 29 is a judgment. This is a reference voltage generation circuit.
The determination reference voltage generation circuit 29 outputs the reference voltages Vref1, Vref
ref2 and Vref3 are output. Reference voltage Vref1
Are the first and second determination values (overcharge determination value V
1), and the reference voltage Vref2 is equal to the undercharge determination value V2.
And the reference voltage Vref3 forms a third determination value (deep discharge determination value V3) referred to in this specification. Reference voltage Vref1
-Reference voltage generating circuit 29 for generating .about.Vref3
FIG. 14 shows an example. Since it is easy to understand the determination reference voltage generation circuit 29, its description is omitted.

The comparator 23 comprises a resistor 20 and a resistor 21
And a reference voltage Vref1 (e.g., corresponding to a battery voltage of 13.7 V) for determining an overcharged state. Battery voltage division (hereinafter simply referred to as battery voltage)
Exceeds the reference voltage Vref1, the comparator 23 outputs a low-level voltage, and the accumulated time during which the low-level voltage is input is integrated by the overcharge time integration circuit 26 as the overcharge state time T1. Further, an overcharge time integrating circuit 2
6 determines whether the overcharge state time T1 within a predetermined observation period (for example, 26 minutes) exceeds a predetermined ratio with respect to the observation period. Specifically, the overcharge state time T1 is a predetermined overcharge determination time Tth1 (for example, 13
Min, that is, 50%). If the overcharge time integrating circuit 26 determines that T1> Tth1, the battery is in an overcharged state and premature draining of the battery is expected. Therefore, a command is sent to the adjustment voltage setting circuit 27 to change the adjustment voltage Vref to a low value. Specifically, the adjustment voltage Vref is reduced by 0.2V. The adjustment voltage Vref changed by the adjustment voltage setting circuit 27 is output to the comparator 30. As is well known, the comparator 30
The adjustment voltage Vref is compared with the battery voltage, and the exciting current interrupt control transistor 13 is controlled to maintain the battery voltage at the adjustment voltage Vref. Conversely, if the overcharge time integrating circuit 26 determines that T1> Tth1, it determines that the overcharge state has been eliminated, and outputs a command to the adjustment voltage setting circuit 27 to return the adjustment voltage Vref to a high value, thereby setting the adjustment voltage. The circuit 27 increases the adjustment voltage Vref by 0.2V. Note that it is naturally possible to perform the hysteresis operation by changing the overcharge determination time Tth1, which is the determination value of the adjustment voltage change, at the time of reduction and at the time of recovery, thereby realizing prevention of hunting and the like.

FIG. 12 shows details of the overcharge time integrating circuit 26. The output of the comparator 23 is input to the UP / DOWN counter 261, and the UP / DOWN counter 261
Counts up every 0.1 seconds of the clock cycle when the battery voltage is higher than the reference voltage Vref1, and
Count down every second. The output of the comparator 23 is a digital delay circuit 262 comprising a shift register.
After being delayed for about 26 minutes by UP / DOWN counter 2
63, the UP / DOWN counter 263 counts up every 0.1 seconds of the clock cycle when the delay battery voltage is higher than the reference voltage Vref1, and counts down every 0.1 seconds when the delay battery voltage is low.

Reference numeral 264 denotes a subtractor, which is UP / DOWN
The count output of the UP / DOWN counter 263 is subtracted from the count output of the counter 261, and the result of the subtraction is output to the digital comparator 265. Therefore, the result of this subtraction is calculated by the comparator 23
Is obtained by subtracting the accumulated value of the output of the comparator 23 up to 26 minutes before the power input time from the accumulated value of the output of
As a result, the accumulated value of the output of the comparator 23 in the last 26 minutes is obtained.

The digital comparator 265 compares the input subtraction result with a preset digital value (here, for example, 0). If the subtraction result is larger than the set digital value (for example, 0),
During the immediately preceding 26 minutes, the battery voltage is changed to the reference voltage Vr.
The total of the periods higher than ef1 is 50 in the observation period (26 minutes).
%, And the adjustment voltage setting circuit 27
To lower the high-level voltage, that is, the adjustment voltage.

FIG. 13 shows a circuit example of the adjustment voltage setting circuit 27. The comparator 24 compares the divided voltage of the battery voltage divided by the voltage dividing circuit including the resistor 20 and the resistor 21 with a reference voltage Vref3 (corresponding to, for example, a battery voltage of 12.5 V) for determining a deep discharge state. I do. When the divided voltage of the battery voltage (hereinafter simply referred to as the battery voltage) falls below the reference voltage Vref3, the comparator 24 outputs a high level voltage to the UP / DOWN counter 2710,
The UP / DOWN counter 2710 counts up every 0.1 seconds of the clock cycle when the battery voltage is lower than the reference voltage Vref3, and counts down every 0.1 seconds when the battery voltage is higher than the reference voltage Vref3. The output of the comparator 24 is delayed by a digital delay circuit 2720 comprising a shift register for about 26 minutes, and then input to an UP / DOWN counter 2730.
The UP / DOWN counter 2730 counts up every 0.1 seconds of the clock cycle when the delay battery voltage is lower than the reference voltage Vref3, and counts down every 0.1 seconds when the delay battery voltage is higher than the reference voltage Vref3.

Reference numeral 2740 denotes a subtractor, which is UP / DOW
UP / DOWN from count output of N counter 2710
The count output of the counter 2730 is subtracted, and the subtraction result is output to the digital comparator 2750. Therefore,
The result of the subtraction is a value obtained by subtracting the accumulated value of the output of the comparator 24 from the time of the input of the power supply to 26 minutes before the time of the input of the power from the accumulated value of the output of the comparator 24 from the time of the input of the power to the present time. Of the output of the comparator 24.

The digital comparator 2750 compares the input subtraction result with a preset digital value (here, 0). If the subtraction result is greater than the set digital value, the digital comparator 2750 compares the result of the last 26 minutes. Since the sum of the periods in which the battery voltage is lower than the reference voltage Vref3 occupies 50% or more of the observation period (26 minutes), it is determined that the battery is in the deep discharge state, the RS flip-flop 273 is set, and the RS flip-flop is set. 273 is an AND gate 2761, 2762, 2763
Cut off. That is, when it is determined that the battery is in the deep discharge state, the AND gates 2761, 2762,
2763 is cut off to inhibit the adjustment voltage from being reduced.

274 is a 4-bit counter,
After the digital comparator 275 outputs the high level, the clock pulse input every two minutes is counted, and after 16 minutes, the RS flip-flop 273 is reset. That is, AND gates 2761, 2762,
2763, once shut down, maintains that state for 16 minutes, during which time the reduction of the regulated voltage is prohibited and strong charging is performed.

Next, when the battery is not in a deep discharge state, R
A case where the S flip-flop 273 outputs a high level will be described. 2751 is a 3-bit counter,
The output of the circuit 26, ie its digital comparator 26
5 is reset through the inverter 2750 when the output of the signal No. 5 is at a low level, that is, in a state where it is not determined that the battery is overcharged. When the digital comparator 265 determines that the battery is overcharged and outputs a high level, the counter 2751 then counts the clock pulse input every two minutes. The output Q0 of the least significant digit (least significant bit), the output Q1 of the intermediate digit, and the output Q2 of the most significant digit of the counter 2751 are AND gates 2761, 2762, and 2, respectively.
763.

Therefore, two minutes after the input of the overcharge state determination signal from the circuit 26, the AND gate 2761 opens to turn on the transistor 277, and the adjustment voltage Vref is set to 0.2.
Reduce V. The on / off of the transistor 277 is the adjustment voltage V
ref corresponds to an increase or decrease of 0.2 V, and the transistor 278
Is equivalent to an increase or decrease of 0.4 V of the adjustment voltage Vref,
The intermittent operation of the transistor 279 is the adjustment voltage Vref of 0.8.
This corresponds to an increase or decrease of V. Thereby, the adjustment voltage V is increased by the increase in the 3-bit count value output from the counter 2751.
ref will gradually increase over eight stages.

When the digital comparator 265 of the block circuit 26 determines that it is not in an overcharged state and outputs a low level, the inverter 2750 resets the counter 2751, shuts off the AND gates 2761 to 2763, and restores the adjusted voltage Vref to the original value. Raised quickly to state. Reference numeral 282 denotes a reference voltage generation circuit, which includes transistors 277 to 280, a zener diode 281, and a resistor, and outputs a total of eight types of reference voltages Vref. Since the reference voltage generation circuit 29 is easily understood, the description is omitted.

Next, the comparator 25 and the insufficient charging time integrating circuit 28 will be described with reference to FIGS. The comparator 25 determines a battery voltage and a reference voltage Vref2 (for example, battery voltage 1)
3.0V). When it is determined that the battery voltage is lower than the reference voltage Vref2, the time (the undercharging state accumulation time T2) is accumulated by the undercharging time accumulation circuit 28. Then, within a predetermined time (for example, 26
It is determined whether the undercharged state accumulated time T2 in (minute) is longer than the undercharge determination reference time Tth2 (13 minutes). When it is determined that T2> Tth2, the battery is in a state of insufficient charge and the battery is expected to run out. Therefore, the idle speed correction value set by the idle speed correction means is changed to a higher value (for example, increased by 50 rpm). I do. Also T
If 2 <Tth2, it is determined that the insufficient charge state has been resolved, and the idle speed is returned to the original level.

Referring to FIG. 15, the insufficient charging time integrating circuit 28 for realizing the above function will be described. The divided voltage of the battery voltage (hereinafter simply referred to as battery voltage) is equal to the reference voltage Vr.
When the voltage falls below ef2, the comparator 25 outputs a high-level voltage to the UP / DOWN counter 2810, and the UP / D
The OWN counter 2810 indicates that the battery voltage is equal to the reference voltage V
If it is lower than ref2, it counts up every 0.1 seconds of the clock cycle, and if it is higher than ref2, it counts down every 0.1 seconds. The output of the comparator 25 is delayed for about 26 minutes by a digital delay circuit 2820 comprising a shift register.
It is input to the UP / DOWN counter 2830 and the UP / D
The OWN counter 283 counts up every 0.1 seconds of the clock cycle when the delay battery voltage is lower than the reference voltage Vref2, and counts down every 0.1 seconds when the delay battery voltage is higher than the reference voltage Vref2.

Reference numeral 2840 denotes a subtractor, UP / DOW
UP / DOWN from count output of N counter 2810
The count output of the counter 2830 is subtracted, and the subtraction result is output to the digital comparator 2850. Therefore,
The result of the subtraction is a value obtained by subtracting the accumulated value of the output of the comparator 25 from the power input time to 26 minutes before the current time from the accumulated value of the output of the comparator 25 from the power input time to the present time. Of the comparator 25.

The digital comparator 2850 compares the input subtraction result with a preset digital value (here, 0). If the subtraction result is greater than the set digital value, the digital comparator 2850 compares the result of the last 26 minutes. Among them, since the total of the periods in which the battery voltage is lower than the reference voltage Vref2 occupies 50% or more of the observation period (26 minutes), it is determined that the battery is in the undercharged state.
The S flip-flop 283 is set, and the RS flip-flop 283 is connected to the transistor 28 of the buffer inverter.
Turn on 4. A clock pulse is input to the reset terminal of the RS flip-flop 283 every two minutes, whereby the data of the RS flip-flop 283 is updated every two minutes.

The ON signal of the transistor 284, which forms a buffer inverter together with the resistor 285, is sent to an engine control circuit (not shown). As a result, the engine control circuit increases the idle speed by a predetermined speed, for example, 50 rpm. Conversely, the engine control circuit reduces the idle speed by a predetermined speed in response to the OFF signal of the transistor 284. (Embodiment 5) Another embodiment will be described with reference to FIG.
However, components having the same functions as those of the above-described embodiment are denoted by the same reference numerals.

This embodiment is different from the first embodiment (see FIG. 1) in that the charge control circuit 4 is divided into an external charge control circuit 47 and an internal charge control circuit 48, which are connected by a signal line 100. Features. External charging control circuit 4 outside the generator
7 is a voltage dividing resistor 2 similar to the charging control circuit 4 of the first embodiment.
0, 21; an A / D converter 18; and a microcomputer 19. The output of the microcomputer 19 is transmitted to a comparator 42 of an internal charge control circuit 48 via a transistor 41 of a buffer inverter for amplifying the power. Is done.

The internal charging control circuit 48 inside the generator includes a comparator 42 for receiving an adjustment voltage signal for receiving the adjustment voltage signal via the signal line 100, an integration circuit including a resistor 44 and a capacitor 45, and an excitation current intermittent. A comparator 46 for controlling the transistor 13 for
7 and 48, and a constant voltage circuit including a resistor 49 and a zener diode 43.

The circuit of the present embodiment is characterized in that the external charging control circuit 47 is provided outside the device in the first embodiment and an A / D converter and a microcomputer are used in the circuit. The operation can be referred to the flowchart of FIG. External control circuit 47
Microcomputer 19 calculates the average voltage of the battery 7, determines the necessity of correcting the adjustment voltage Vref, and calculates the corrected adjustment voltage. The microcomputer 19 obtains a duty signal corresponding to the calculated adjustment voltage. For example, when the adjustment voltage is 15V, the duty is 90%, when the adjustment voltage is 12V, the duty is 10%, and other values are calculated by linear interpolation. The obtained duty signal is
The signal is transmitted by the transistor 41 to the charging control circuit 48 built in the generator 1. Adjustment voltage receiving comparator 4
2 compares the received duty signal with a reference voltage output from the constant voltage circuit, shapes the waveform, averages the waveform by an integrating circuit including a resistor 44 and a capacitor 45 in the next stage, and again converts the duty signal into an adjustment voltage. Is converted to an analog reference voltage. The comparator 46 compares the adjusted voltage Vref set in this way with the output voltage of the generator, and controls the output of the generator by interrupting the exciting current.

The signal between the external charge control circuit 47 and the internal charge control circuit 48 is the duty signal (PW
In addition to the M signal, any known signal or analog voltage may be used as long as the signal can represent the adjustment voltage. That is, according to this embodiment, the internal charging control circuit 48 inside the generator
It has a function of comparing ref with the divided voltage of the generator output voltage to generate an output signal to the excitation current drive circuit. The external charge control circuit 47 determines the integrated amount of the battery voltage and sets the adjustment voltage Vref based on the determination, and transmits the value of the adjustment voltage as a signal to the internal charge control circuit 48 inside the generator. That is, in this embodiment, since the detection of the battery voltage is performed by the external device, there is an advantage that the control device in the generator 1 does not need a terminal for detecting the battery voltage. Also, unlike FIG. 1, the on / off of the exciting current driving transistor 13 is not directly treated as a signal, but is transmitted as the adjustment voltage signal Vref. Therefore, it is possible to detect an abnormality such as disconnection of a terminal and perform fail-safe control. For example, in FIG. 16, the duty signal output from the transistor 41 is 0% or 10%.
When it is 0%, it can be determined that there is an abnormality such as disconnection of a terminal. The external charge control circuit 47 can be built in another controller (for example, an engine control ECU). (Other Embodiments) Other embodiments will be described below.

In a preferred embodiment, the set time set in step 102 of FIGS. 2, 4 and 6 is set to be longer than at least the shortest intermittent cycle of the electric radiator fan for cooling the vehicle cooling water. By doing so, it is possible to prevent the adjustment voltage from being changed due to a change in the battery voltage due to frequent intermittent operation of the electric radiator fan. In a preferred embodiment, the down amount of the adjustment voltage at the time of overcharge detection set in step 138 of FIGS. 2, 4 and 6 is the adjustment amount of the adjustment voltage defined by this down amount and the routine execution cycle of step 102. The rate of change is set to be in the range of 0.01 to 0.1 V per second. In this way, a sudden change in the battery voltage due to a sudden change in the adjustment voltage is prevented from being perceived by the driver or the occupant while an overcharge due to a slow adjustment in the adjustment voltage is prevented from becoming a problem. can do. Of course, it is preferable to maintain the rate of change in this range even when the adjustment voltage increases.

However, when a battery undercharged state or a deeper discharge state that is more serious is detected based on the integrated amount of battery voltage, the adjustment voltage is changed more quickly than the rate of change at the time of overcharge elimination in order to suppress battery deterioration. Preferably, it is changed. In a preferred embodiment, the charging control circuit 4 of FIG. 1, that is, the voltage control means, the detection means, and the adjustment voltage changing means according to the present invention are built in the vehicle alternator.
This makes it possible to simplify the device size and wiring. On the other hand, in the embodiment shown in FIG. 16, the voltage control means is built in the vehicle alternator, and the external charging control circuit 47 serving as the detection means and the adjustment voltage changing means is provided outside the vehicle alternator. You. With this configuration, the detection unit and the adjustment voltage changing unit can be configured by the microcomputer device disposed in the environment where the noise is sufficiently shielded,
Complex signal processing for changing the adjustment voltage can be performed under highly reliable conditions.

In a preferred embodiment, the judgment value for judging the integrated amount of the battery voltage is shifted based on the temperature of the battery or a parameter which changes accordingly.
For example, the determination reference voltage generation circuit 29 shown in FIG. 14 is built in a vehicle alternator, and includes a reference voltage Vref1 (overcharge determination value V1), a reference voltage Vref2 (undercharge determination value V2), and a reference voltage Vref3 ( The deep discharge determination value V3) is generated as a partial voltage of the constant voltage diode ZD. Further, in FIG. 14, the output voltage of the voltage dividing circuit including the resistors R11 and R12 is input to the transistor 311. When the temperature of the transistor 311 is low, the transistor 311 is in an unsaturated or off state, and the reference voltages Vref1 to Vr
Of the currents supplied to the resistor groups R15 to R19 that generate ef3, the shunt to the resistor R13 is small or zero.
However, when the temperature of the transistor 311 becomes high, the transistor 311 is completely turned on and the shunt current increases, and as a result, the reference voltages Vref1 to Vref3 decrease. R13 is a collector resistance, and R14 is an emitter resistance for adjusting the level of the collector current and the like.

That is, in the circuit 29 shown in FIG. 14, when the temperature of the generator 1 rises, the reference voltages Vref2 and Vref3 decrease. Since the temperature of the generator 1 has a positive correlation with the temperature of the battery 7 installed in the same engine room, when the temperature of the battery 7 increases, the reference voltage Vre
f1 and Vref3 are reduced. As a result, if the battery temperature rises and the voltage level that causes overcharge decreases, the overcharge determination value can be reduced accordingly, realizing optimal power generation control without inducing overcharge and reducing fuel consumption. Can also be fulfilled. In FIG. 14, since the battery temperature is substituted by the so-called regulator temperature, the configuration can be simplified.

A preferred embodiment will be described with reference to the flowchart of FIG. However, FIG. 17 shows a step 101 added to the flowcharts shown in FIGS. 2, 4, and 6. In this embodiment, the engine (not shown) is started and
The adjustment voltage is not changed for 0 minutes (step 10).
1). With this configuration, the change in the adjustment voltage is prohibited for a predetermined time after the start, which is likely to cause insufficient charging, so that the occurrence of insufficient charging is suppressed.

A preferred embodiment will be described with reference to the flowchart of FIG. However, FIG. 17 shows a step 103 added to the flowcharts shown in FIG. 2, FIG. 4, and FIG. In this embodiment, the elapsed time after the engine (not shown) is started is counted, and the determination values V1, V2, VV3 are changed according to the elapsed time. The temperature of the battery 7 rises with the elapsed time after the start of the engine,
Since the overcharge level also decreases, the determination values V1, V2, and V3 are reduced accordingly. With this configuration, with a simple configuration, the regulated voltage can be reduced without causing overcharging and deficient charging, the power generation level can be reduced, and fuel consumption can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a vehicle charging device to which a voltage control device for a vehicle AC generator according to the present invention is applied.

FIG. 2 is a flowchart showing a control operation (first embodiment) of a microcomputer 19 of FIG. 1;

FIG. 3 is a flowchart showing a control operation (first embodiment) of the microcomputer 19 of FIG. 1;

FIG. 4 is a flowchart showing another control operation (second embodiment) of the microcomputer 19 of FIG. 2;

FIG. 5 is a flowchart showing another control operation (second embodiment) of the microcomputer 19 of FIG. 2;

FIG. 6 is a flowchart illustrating another control operation (third embodiment) of the microcomputer 19 of FIG. 2;

FIG. 7 is a flowchart showing another control operation (third embodiment) of the microcomputer 19 of FIG. 2;

FIG. 8 is a timing chart showing changes in the battery voltage, the average value, and the adjustment voltage in a mode in which the engine speed increases from an idle speed to a predetermined high speed value in a cycle of about 5 minutes as a model during city driving. is there.

FIG. 9 is a timing chart showing changes in the battery voltage, its average value, and the adjustment voltage in a mode in which the engine speed increases for a long time after the engine speed increases as a model for suburban driving.

FIG. 10 is a timing chart showing changes in a battery voltage, its average value, and a regulated voltage in a mode in which idle rotation continues for a long time.

FIG. 11 is a block diagram showing a fourth embodiment of a vehicular charging apparatus to which the vehicular AC generator voltage control device of the present invention is applied.

FIG. 12 is a circuit diagram illustrating an example of a block circuit 26 illustrated in FIG. 11;

FIG. 13 is a circuit diagram illustrating an example of a block circuit 27 illustrated in FIG. 11;

FIG. 14 is a circuit diagram illustrating an example of a block circuit 29 illustrated in FIG. 11;

FIG. 15 is a circuit diagram showing an example of a block circuit 28 shown in FIG.

FIG. 16 is a block diagram showing a fifth embodiment of a vehicular charging apparatus to which the vehicular AC generator voltage control device of the present invention is applied.

FIG. 17 is a flowchart showing a modification of the flowcharts of FIGS. 2, 4, and 6;

FIG. 18 is a flowchart showing a modification of the flowcharts of FIGS. 2, 4, and 6;

[Explanation of symbols]

1 is a vehicle alternator, 3 is an exciting current drive circuit (part of the voltage adjusting means), 4 is a charging control circuit (the rest of the voltage adjusting means), 19 is a microcomputer (detecting means, adjusted voltage changing means), and step. 108, 208, 308 are detection means, steps 116, 138 are adjustment voltage change means, step 1
Reference numerals 18 and 136 denote idle adjusting means.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H02P 9/14 H02P 9/14 H

Claims (21)

[Claims] 1. A voltage regulator for controlling an output of a vehicle alternator so as to match a voltage of a battery charged by a vehicle alternator mounted on a vehicle and driven by an internal combustion engine with a predetermined regulation voltage. A predetermined observation period set longer than at least one of an interval at which the number of revolutions of the internal combustion engine increases or decreases according to running and stop of the vehicle, and an operation interval of a predetermined electric load device that operates intermittently Detecting means for outputting an integrated detected value corresponding to the integrated amount of the battery voltage in the above based on the battery voltage or its related value observed during the observation period; and the integrated detected value output from the detecting means. And a regulation voltage changing means for changing the regulation voltage based on the following. 2. The voltage control apparatus for an automotive alternator according to claim 1, wherein the observation period is set to be longer than a shortest intermittent cycle of an electric radiator fan attached to the internal combustion engine. Voltage control device for vehicle alternator. 3. The voltage control device for an automotive alternator according to claim 1, wherein the observation period is set to 3 to 30 minutes. 4. The voltage control apparatus for an AC generator for a vehicle according to claim 1, wherein the adjustment voltage changing means decreases the adjustment voltage when the integrated detection value exceeds a first determination value. A voltage control device for an automotive alternator, wherein the adjustment voltage is increased when the integrated detection value falls below a second determination value lower than the first determination value. 5. The voltage control device for an automotive alternator according to claim 1, wherein said adjustment voltage changing means sets the rate of change of said adjustment voltage to a predetermined maximum value or less when said adjustment voltage increases or decreases. A voltage control device for a vehicular alternator characterized by regulating. 6. The voltage control device for an automotive alternator according to claim 5, wherein the adjustment voltage changing means is configured to output a predetermined third voltage whose battery voltage or the integrated detection value is lower than the second determination value. The adjustment voltage is increased at a predetermined rapid increase rate when the determination value is further lower than the determination value, and the adjustment voltage is increased at a change rate smaller than the rapid increase rate when the integrated detection value exceeds the first determination value. Decreasing the integrated voltage at a rate of change smaller than the rapid rise rate when the integrated detection value falls below a second decision value lower than the first decision value. Generator voltage control device. 7. The vehicular AC generator voltage control device according to claim 5, wherein the adjustment voltage changing means sets the rate of change to 0.01 V / min or more. AC generator voltage control device. 8. The voltage control device for an AC generator for a vehicle according to claim 5, wherein the adjustment voltage changing means sets the rate of change to 0.1 V / min or less. A voltage control device for an AC generator for a vehicle. 9. The voltage control device for an automotive alternator according to claim 1, wherein the integrated detection value is still lower than a predetermined value after the adjustment voltage has increased to a predetermined value. A voltage control apparatus for an AC generator for a vehicle, comprising: an idle adjusting unit for increasing an idle speed of the engine. 10. The voltage control device for an automotive alternator according to claim 4, wherein when the integrated detection value exceeds the first determination value, priority is given to a decrease in the adjustment voltage. A voltage control device for an AC generator for a vehicle, comprising: an idle adjusting means for reducing an idle speed of the engine. 11. The voltage control device for an AC generator for a vehicle according to claim 1, wherein the adjusting voltage changing unit is configured to: A voltage control device for an AC generator for a vehicle, wherein a decrease in the adjustment voltage by the adjustment voltage changing means is regulated. 12. The voltage control device for an AC generator for a vehicle according to claim 1, wherein the voltage adjustment means, the detection means, and the adjustment voltage change means include:
A voltage control device for a vehicle alternator, which is attached to the vehicle alternator. 13. The vehicular AC generator voltage control device according to claim 1, wherein the voltage adjusting means is provided in the vehicular AC generator.
The vehicle, wherein the detection unit and the adjustment voltage changing unit are provided outside the vehicle alternator, and the adjustment voltage changing unit transmits an adjustment voltage signal related to the adjustment voltage to the voltage adjustment unit. Voltage control device for AC generator. 14. The voltage control apparatus for an AC generator for a vehicle according to claim 1, wherein the adjustment voltage changing means changes the adjustment voltage for a predetermined time after starting the internal combustion engine. A voltage control device for an AC generator for a vehicle, wherein the voltage control is interrupted. 15. The voltage control device for an automotive alternator according to claim 4, wherein the adjustment voltage changing means shifts the determination value based on the temperature of the battery or a parameter corresponding thereto. A voltage control device for a vehicular alternator, characterized in that: 16. The voltage control device for an automotive alternator according to claim 15, wherein the adjustment voltage changing means shifts the determination value based on a temperature of the voltage adjustment means constituting the parameter. A voltage control device for an AC generator for a vehicle. 17. The voltage control device for an automotive alternator according to claim 15, wherein the adjustment voltage changing means shifts the determination value based on an elapsed time after the start of the internal combustion engine, which constitutes the parameter. A voltage control device for a vehicular alternator, comprising: 18. The voltage control device for an automotive alternator according to claim 1, wherein the integrated detection value comprises a high-range reduced battery voltage obtained by reducing a high-frequency component of the battery voltage. A voltage control device for an AC generator for a vehicle. 19. A vehicle AC generator according to claim 18, wherein said integrated detection value comprises an average value of said battery voltage during said observation period. Generator voltage control device. 20. The voltage control apparatus for an automotive alternator according to claim 1, wherein the integrated detection value is a signal including a ratio of a period in which the voltage of the battery exceeds a predetermined value within the predetermined period. A voltage control device for a vehicle alternator, characterized in that: 21. The voltage control device for an automotive alternator according to claim 1, wherein the integrated detection value is a signal including an accumulated value of an overcharge current flowing into the battery during the predetermined period. A voltage control device for a vehicle alternator.