JPH07245885A - Power generation controller for vehicle - Google Patents

Abstract

PURPOSE:To prevent the dropping of a terminal voltage, overshoot, hunting and the like when the voltage is recovered from the generation of overvoltage by immediately restarting the ordinary generation control when the terminal voltage of a battery becomes lower than the normal judging value during the generation stopping control. CONSTITUTION:A voltage comparing means 41 compares an overvoltage judging value Vm and a specified output OT2. When Vm<=OT2, an overvoltage detection signal E is generated and inputted into a field-current cutoff means 35 and a cutoff continuation means 37. The cutoff continuation means 37 continues the generation of a cutoff continuation signal G and continues the cutoff of the field current cutoff means 36 by the specified time. Meanwhile when it is judged that Vm>OT2, a normal-state detecting means 38 compares a terminal voltage VB of a battery 4 and a normal judging value Vn. When it is judged that VB<=Vn, a cutoff releasing means 39 generates a releasing signal P, and the cutoff continuation means 37 performs the operation so that a field-current control means 34 performs the ordinary generation control. Thus, the power generation control is restarted when the terminal voltage VB of the battery 4 is sound.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular power generation control device having a generator overvoltage suppressing function and constant control of a battery terminal voltage, and more particularly to improving overvoltage detection reliability and hunting for power generation stop control. The present invention relates to a vehicle power generation control device that prevents the above.

[0002]

2. Description of the Related Art Conventionally, in this type of power generation control device for a vehicle, in order to prevent an inconvenience caused by an overvoltage output when an abnormality occurs in the power generation control means, a rectification of one or more phases is performed from a stator coil in the generator. Output (usually about 14V)
Is detected, and the rectified output has an overvoltage determination value (for example, 20V
When it is detected that the voltage is higher than the above, the field current is cut off to stop the normal power generation control and suppress the overvoltage.

Further, when the rectified output returns below the overvoltage judgment value during the field current cutoff control, the field current cutoff control is continued for a certain predetermined time in order to prevent hunting, etc. Return to power generation control. The overvoltage determination value in the conventional device is a preset constant value.

By the way, the abnormality of the power generation control means for generating the overvoltage is mainly due to the disconnection of the connecting line between the generator and the battery or the contact failure, and the electric power supplied to the battery is disconnected from the electric load and the electric load. This is due to joining the electronic device. If the power generation is not stopped when an overvoltage occurs, a voltage of several tens of volts (volts) or more is applied to the electric load and the electronic device connected in parallel to the battery, resulting in the destruction of the electric load or the like.

Therefore, in order to prevent such an inconvenience, it is necessary to stop the field current immediately when an overvoltage occurs to surely stop the power generation. Further, when the overvoltage state is returned to the undervoltage state or less, it is desirable that the normal power generation control be started after a certain predetermined time has passed, and that the cutoff time has a margin.

FIG. 5 is a block diagram showing a general vehicle power generation control device. In the figure, 1 is an engine for driving the vehicle to travel, 2 is a generator driven by the engine 1, and the generator 2 is the following 21 to 23, D1 and D.
It consists of two.

Reference numeral 21 is a stator coil for outputting three-phase AC, 22 is a field coil magnetically coupled to the stator coil 21 and driven by the engine 1, and 23 is full-wave rectification of the three-phase AC output from the stator coil 21. Rectifier output OT1 and D1 is a field coil 2
A flywheel diode D2 connected in parallel with 2 is a diode for detecting the rectified output OT2 for one phase of the rectifier 23. Here, the case where the rectified output OT2 for one phase is representatively shown is shown, but the rectified output for three phases may be derived.

Reference numeral 3 is a key switch which is inserted into the output line of the generator 2 and is turned on when the engine 1 is started. Reference numeral 4 is an on-vehicle battery which is supplied with power by the rectified output OT1 via the key switch 3 and 5 is a battery 4 Is an in-vehicle electric load connected in parallel to the power generator 2 or the battery 4, and similarly to the electric load 5, an in-vehicle electronic device connected in parallel to the battery 4.

Reference numeral 8 denotes various sensors for detecting the operating state D of the engine 1. As the operating state D, for example, the engine speed, cooling water temperature, intake air temperature, vehicle speed, start switch signal, etc. are detected. Reference numeral 10 denotes a control unit for controlling the generator 2 based on the terminal voltage VB of the battery 4, the rectified output OT2, the operating state D, and the like, and includes the following 11 and 12.

A field switch 11 controls the field current IF flowing in the field coil 22 and is composed of a grounded-emitter transistor whose collector is connected to the field coil 22. 12 is a field switch 11
Is a power generation control means for generating a control signal C (on / off control signal) for the base of, and includes a microcomputer having an arithmetic processing function (described later) based on various information VB, OT2 and D.

The power generation control means 12 includes adjustment voltage setting means for detecting the operating state D of the engine 1 and determining the optimum adjustment voltage VR of the battery 4, and in the normal control, the terminal voltage VB of the battery 4 is the adjustment voltage. The control signal C is generated so as to match VR. As a result, the field switch 11 is controlled to be turned on / off to adjust the field current IF, thereby controlling the power generation amount of the generator 2.

FIG. 6 is a characteristic diagram showing the change in the battery adjustment voltage VR and the overvoltage determination value Vmax with respect to the operating state D (for example, intake air temperature). The adjustment voltage VR is high when the intake air temperature is low and the intake air temperature is low. It is set low when it is high, and the overvoltage determination value Vmax is a constant value that is set with a margin voltage ΔV with respect to the adjustment voltage VR.

It can be seen that when the overvoltage determination value Vmax is constant as shown in FIG. 6, the margin voltage ΔV with respect to the adjustment voltage VR becomes smaller for a low intake air temperature, and therefore the possibility of erroneous overvoltage determination increases.

Further, the power generation control means 12 controls the regulated voltage VR.
Rectified output O by setting a higher overvoltage determination value Vmax
When T2 is equal to or higher than the overvoltage determination value Vmax, an overvoltage detecting means for detecting an abnormality occurrence in the control unit 10 and the like, and the field switch 1 by turning off the control signal C when the overvoltage is detected.
1 is immediately turned off to stop the power generation, and a field current interruption means is included.

Further, the power generation control means 12 detects an abnormality even when the rectified output OT2 cannot be obtained due to an abnormality of the generator 2, shuts off the field current IF and lights an alarm lamp (not shown). The driver is then warned. In order to detect such an abnormality of the generator 2 and to reliably detect abnormal disconnection of the battery 4 or the like, it is meaningful to detect the rectified output OT2 from the generator 2 as shown in FIG.

Further, when the rectified output OT2 returns to the overvoltage determination value Vmax or less during the power generation stop control, the power generation control means 12 continues the power generation stop control until a predetermined time elapses, and after the predetermined time elapses, the normal power generation control is performed. By restarting the power generation control, hunting or the like is prevented.

FIG. 7 is a block diagram schematically showing an example of an overvoltage generation state, showing an overvoltage state for the electric load 5 when the battery 4 is disconnected during normal power generation control. 7, (a) is a normal state in which the generator 2 is supplying power to the electric load 5 in the battery 4, (b) is an abnormal state in which the power supply line to the battery 4 is disconnected, and i1 is the battery 4 Supply current, i2 is electric load 5
Is the current supplied to.

Next, the operation of the conventional vehicular power generation control device will be described with reference to FIGS. First, the power generation control means 12 reads the operating state D of the engine 1 from the various sensors 8 and at the same time, outputs the terminal voltage VB of the battery 4.
The rectified voltage OT2 is read, and the regulated voltage VR of the battery 4 is determined based on the operating state D.

At this time, the adjustment voltage VR is set high when the intake air temperature is low and low when the intake air temperature is high, as shown in FIG. Then, the overvoltage determination value Vmax higher than the adjustment voltage VR is set, and the overvoltage determination value Vmax is compared with the rectified output OT2.

If the rectified output OT2 is the overvoltage judgment value Vm
If it is ax or more, it is determined that an overvoltage has occurred, the control signal C is turned off, the field switch 11 is turned off, and the field current IF is shut off.

For example, as shown in FIG. 7, when the battery 4 is disconnected due to an abnormality in the supply line, the supply current i1
And i2 flow into the electric load 5, and an overvoltage is applied to the electric load 5. If i1 = i2 = 20 A (amperes), a current twice as high as the normal current flows in such an abnormal condition, and thus a voltage twice as high (about 28 V) is applied to the electric load 5. However, the above power generation stop control prevents the application of overvoltage.

Further, when the disconnection abnormality of the battery 4 occurs at the portion A in FIG. 5, it is possible to detect the abnormality from the terminal voltage VB, but when the disconnection abnormality occurs at the portion B, Abnormality cannot be detected from the terminal voltage VB. Therefore, the rectified output OT2 from the generator 2 can reliably detect the disconnection abnormality as shown in FIG.

When the abnormal state is released and the rectified output OT2 becomes equal to or lower than the overvoltage determination value Vmax, the normal power generation control is resumed after a lapse of a predetermined time, and the terminal voltage VB of the battery 4 is adjusted by the control of the field current IF. Controlled by VR.
The field current IF is controlled by, for example, PWM control by the control signal C, that is, by adjusting the duty ratio for turning on the field switch 11.

However, since the overvoltage determination value Vmax is a constant value, as is apparent from FIG. 6, the margin voltage ΔV becomes small when the intake air temperature is low, and the rectified output OT2 varies within the allowable range. However, there is a possibility that an overvoltage occurrence state is detected by a voltage ripple component or the like and unnecessary power generation stop control is performed. In particular, there is a high possibility that the overvoltage state is erroneously detected due to variations in the characteristics of the generator 2 and the battery 4, environmental temperature, and various conditions such as the adjustment voltage VR and the overvoltage determination value Vmax according to the operating state D. May be.

Further, once it is determined that an overvoltage has occurred and the control for shutting off the field current IF is started, even if the rectified output OT2 returns to normal and falls below the overvoltage determination value Vmax, a predetermined time elapses. Since the cutoff control of the field current IF is continued, the terminal voltage VB of the battery 4 may be significantly lower than the adjustment voltage VR at the time point when the normal power generation control is restarted after the lapse of a predetermined time.

Further, when power generation is suddenly restarted from such an over-discharged state, a voltage overshoot occurs, and when the overshoot is large, it is determined again that an overvoltage has occurred and the terminal voltage of the battery 4 is increased. A hunting phenomenon of VB will occur.

[0027]

As described above, the conventional vehicular power generation control device detects the rectified output OT2 from the generator 2 in order to cut off the field current IF when an overvoltage occurs. Overvoltage determination value Vmax for output OT2
Is a constant value, and the overvoltage determination value Vmax is only set to a value higher than the rectified output OT2 under normal conditions by about several V. Therefore, even during the normal power generation control, the rectified output OT2 may exceed the overvoltage determination value Vmax due to the deterioration of the battery 4, the environment such as temperature, the difference in the adjustment voltage VR, and the like, and the overvoltage occurrence state may be erroneously detected. However, there is a problem that the power generation stop control is performed in vain.

Further, when it is judged that the overvoltage has occurred and the cutoff control of the field current IF is started, even if the rectified output OT2 falls below the overvoltage judgment value Vmax, the cutoff control of the field current IF is performed until a predetermined time elapses. In order to do so, the terminal voltage VB
However, there is a problem in that it is significantly lower than the adjustment voltage VR. Further, at this time, since power generation is suddenly restarted, a voltage overshoot occurs and it is determined again that an overvoltage has occurred, and there is a problem that rectification output OT2 and terminal voltage VB hunting occurs. It was

Claim 1 of the present invention has been made to solve the above problems, and when the terminal voltage of the battery falls below the normal judgment value during the power generation stop control, the normal power generation is immediately performed. An object of the present invention is to obtain a vehicular power generation control device which prevents terminal voltage drop, overshoot, hunting and the like when the control is restarted by restarting control.

According to the second aspect of the present invention, erroneous detection of the overvoltage occurrence state due to the deterioration of the battery during the normal power generation control, the temperature and other environments, and the variations in various conditions such as the regulated voltage is prevented. It is an object of the present invention to obtain a vehicular power generation control device with further improved reliability.

According to a third aspect of the present invention, the margin voltage between the regulated voltage and the overvoltage judgment value is kept large, and the battery deterioration during normal power generation control, temperature and other environments, and various conditions such as the regulated voltage. It is an object of the present invention to obtain a vehicular power generation control device that prevents the operation of the overvoltage cutoff control due to the difference between the above, and optimizes the overvoltage generation, the power generation control at the time of restoration, and the normal power generation control.

[0032]

A vehicle power generation control device according to claim 1 of the present invention rectifies a field coil driven by an engine, a stator coil magnetically coupled to the field coil, and an AC output of the stator coil. A generator having a rectifier, a battery charged by a rectified output of the generator, an electric load supplied with electric power from the generator or the battery, a field switch for controlling a field current flowing in a field coil, and an engine Power generation control is provided with various sensors that detect the operating state, and a power generation control unit that controls the field switch according to the operating state and adjusts the rectified output of the generator to control the terminal voltage of the battery to a predetermined regulated voltage. A battery voltage detecting means for detecting a terminal voltage of the battery and an operating state of the engine. And the rolling condition detection means, and adjusting voltage setting unit for setting the adjustment voltage of the battery depending on the operating conditions,
Field current control means for controlling the field switch so that the rectified output matches the regulated voltage, rectified output detection means for detecting the rectified output of the generator, and overvoltage power generation state when the rectified output shows the overvoltage judgment value or more. Overvoltage detection means for detecting the field voltage, field current interruption means for interrupting the field current when the overvoltage power generation state is detected, and when the rectified output becomes lower than the overvoltage determination value after the field current is interrupted, In a vehicle power generation control device including a cutoff continuation unit that keeps the cutoff state of the magnetic current for a predetermined time, the power generation control unit sets the terminal voltage of the battery to a normal determination value lower than the overvoltage determination value while the field current is continuously interrupted. The normal state detecting means for detecting the normal voltage state when the terminal voltage of the battery is equal to or lower than the normal judgment value, and the interruption of the field current when the normal voltage state is detected. It is intended to include the cutoff releasing means for releasing the.

According to a second aspect of the present invention, there is provided the vehicle power generation control device according to the first aspect, wherein the overvoltage detecting means is
Counting means for counting the number of times the field current interruption control occurs due to overvoltage detection after the engine is started, and when the number of interruption control occurrences reaches or exceeds a predetermined number, the overvoltage determination value is updated to a voltage higher than the previous time. And an overvoltage determination value updating means.

According to a third aspect of the present invention, there is provided the vehicle power generation control device according to the first or second aspect, wherein the overvoltage detection means sets the overvoltage determination value in response to the increase or decrease of the adjustment voltage. It includes a value setting means.

[0035]

According to the first aspect of the present invention, when the terminal voltage of the battery becomes equal to or lower than the normal determination value lower than the overvoltage determination value during the power generation stop control, the normal power generation control is immediately restarted to prevent the overvoltage from occurring. Prevents terminal voltage drop, overshoot, and hunting at the time of restoration.

Further, according to the second aspect of the present invention, when the terminal voltage equal to or lower than the normal determination value is detected, the power generation control is restored, and the terminal voltage of the battery drops at the time of recovery from the overvoltage occurrence, and the overvoltage occurs. Prevents shoots, hunting, etc., and counts the number of times the field current is interrupted by overvoltage detection, that is, the number of times that the interrupted control returns to power generation control, and when the predetermined number is reached, the overvoltage determination value is set to a large value. . As a result, the operation of the cutoff control due to the erroneous detection of the overvoltage due to the deterioration of the battery during the normal power generation control, the temperature and other environments, and the variations in various conditions such as the adjustment voltage is prevented, and the reliability of the overvoltage detection is further improved.

Further, according to claim 3 of the present invention, when the terminal voltage equal to or lower than the normal judgment value is detected, the power generation control is restored, and the terminal voltage of the battery drops at the time of recovery from the overvoltage, It prevents shoots, hunting, etc., and sets the overvoltage determination value in response to an increase or decrease in the adjustment voltage. As a result, the margin voltage between the regulated voltage and the overvoltage judgment value is kept large regardless of the increase or decrease of the regulated voltage, and the deterioration of the battery during normal power generation control, temperature and other environments, and differences in various conditions such as the regulated voltage. Prevents over-voltage cutoff control from malfunctioning and optimizes power generation control at overvoltage generation and recovery, and normal power generation control.

[0038]

【Example】

Example 1. Embodiment 1 of the present invention (corresponding to claims 1 to 3) will be described below in detail with reference to the drawings. FIG. 1 is a functional block diagram showing the configuration of the power generation control means according to the first embodiment of the present invention. 12A corresponds to the power generation control means 12, and 2, 4, 8 and 11 are the same as those described above. . The overall configuration of the first embodiment of the present invention is as shown in FIG.

In FIG. 1, 30 is a battery voltage detecting means for detecting the terminal voltage VB of the battery 4, 31 is an operating state detecting means for detecting an operating state D from the various sensors 8,
Reference numeral 32 is a rectified output detecting means for detecting the rectified output OT2 of the generator 2, 33 is a regulated voltage setting means for setting the regulated voltage VR of the battery 4 according to the operating state D, and 34 is a battery 4
Is a field current control means for controlling the field switch 11 so that the terminal voltage VB of the field voltage VB matches the adjustment voltage VR.
These functional configurations 30 to 34 are the same as those of the conventional power generation control device 1
It is similar to the case of 2.

Reference numeral 35 indicates that the rectified output OT2 is the overvoltage judgment value Vm.
An overvoltage detecting means for generating an overvoltage detection signal E when the above is shown, and 36 is a field current I in response to the overvoltage detection signal E.
It is a field current interrupting means for generating an interrupting signal F for interrupting F. The cutoff signal F is input to the field current control means 34.

Reference numeral 37 is a cutoff continuation means having an overvoltage cut timer (described later) which operates in response to the overvoltage detection signal E, and when the rectified output OT2 becomes lower than the overvoltage judgment value Vm after the field current IF is cut off. In addition, the continuation signal G for continuing the cutoff state of the field current IF for a predetermined time is generated. The overvoltage cut timer in the interruption continuation means 37 is composed of a down counter and is reset by a release signal (described later). Further, the continuation signal G is input to the field current interruption means 36.

Reference numeral 38 denotes a normal state detecting means responsive to the terminal voltage VB of the battery 4, which determines the terminal voltage VB to be a normal judgment value Vn lower than the overvoltage judgment value Vm (for example, the adjustment voltage when the field current IF is continuously cut off). 12 which is slightly lower than VR
The normal detection signal M is generated when the terminal voltage VB is equal to or lower than the normal determination value Vn, that is, the normal voltage state.

Reference numeral 39 denotes a disconnection canceling means for generating a canceling signal P for canceling the interruption of the field current IF in response to the normal detection signal M, and the canceling signal P serves as a reset signal for the interruption continuing means 37.

FIG. 2 is a functional block diagram showing the structure of the overvoltage detection means 35 in FIG. 1. Reference numeral 40 is an overvoltage determination value setting means for setting an overvoltage determination value Vm in response to an increase / decrease in the adjustment voltage VR, and 41 is It is a voltage comparison unit that generates an overvoltage detection signal E when the rectified output OT2 is equal to or higher than the overvoltage determination value Vm.

Reference numeral 42 is an operating state D and an overvoltage detection signal E.
The number of occurrences N of interruption control of the field current IF due to overvoltage detection is counted after the engine 1 is started. Reference numeral 43 denotes an overvoltage determination value updating means that responds to the number N of times of occurrence of the overvoltage detection signal E, and updates the overvoltage determination value Vm to a voltage higher than the previous time when the number of times N of occurrence of overvoltage cutoff control reaches a predetermined number K or more. To generate an update signal H for

FIG. 3 is a characteristic diagram showing the relationship between the adjustment voltage VR and the overvoltage judgment value Vm, and the margin voltage ΔV (= Vm-V).
R) indicates a state in which it is always set to a large value regardless of the operating state D (intake air temperature), that is, the fluctuation of the adjustment voltage VR.

In this case, the power generation control means 12A has an abnormality in the control unit 10 (see FIG. 5) or the like, and the rectified output O
When T2 exceeds the overvoltage determination value Vm determined based on the adjustment voltage VR, the field switch 11 is immediately turned off to stop the power generation. When the rectified output OT2 returns to the overvoltage determination value Vm or less, the normal power generation control is restarted after a predetermined time.

When the terminal voltage VB becomes equal to or lower than a predetermined normal judgment value Vn (a value lower than the overvoltage judgment value Vm) within a predetermined time during the cutoff control, the normal power generation control is immediately restarted. Further, when the interruption control at the time of overvoltage repeatedly occurs for a predetermined number of times K or more after the engine is started, it is regarded not as the interruption control at the time of abnormality but as an erroneous detection, and the overvoltage determination value Vm is updated to a high value and is erroneously detected. Make it harder. This is because, when an abnormality actually occurs, the overvoltage detection state is fixed, and the cutoff and restoration are not repeated.

Next, the operation of the first embodiment of the present invention will be described in detail with reference to the flowchart of FIG. 4 together with FIGS. 1 to 3 and 5. The series of processes shown in FIG. 4 is assumed to be executed in the power generation control means 12A at regular intervals.

First, in step S201, the operating state detecting means 31 in the power generation control means 12A causes the engine 1 to operate.
Operating state D (rotation speed, engine cooling water temperature,
The intake air temperature, vehicle speed, start switch signal, etc.) are read from various sensors 8. Further, the battery voltage detection means 30 and the rectified output detection means 32 read the terminal voltage VB of the battery 4 and the rectified output OT2 of the generator 2 in step S202.

Then, the adjusting voltage setting means 33 determines the battery 4 based on the operating state D in step S203.
The regulated voltage VR for is determined as shown in FIG. At this time, the adjustment voltage VR is set high when the intake air temperature is low and low when the intake air temperature is high as described above.

Next, the field current control means 34 generates the control signal C for the field switch 11 based on the adjustment voltage VR in the normal state so that the terminal voltage VB of the battery 4 matches the adjustment voltage VR. , Controls the field current IF of the field coil 22 in the generator 2.

On the other hand, the adjustment voltage VR is the overvoltage detection means 35.
Is input to the overvoltage determination value setting means 40 in the overvoltage detection means 35, and the adjustment voltage VR has a margin voltage ΔV (about several V).
Is added to determine the overvoltage determination value Vm. In the initial state, the counter value of the counting means 42, that is, the number of times N the overvoltage detection signal E is generated, is 0, and the update signal H from the overvoltage determination value updating means 43 is not generated.

Here, the overvoltage determination value updating means 43 in the overvoltage detection means 35 compares in step S204 whether the overvoltage occurrence number N is a predetermined number K or more. The overvoltage occurrence count N counted by the counter in the counting means 42 is reset to 0 when the start switch signal in the operating state D is ON.

The predetermined number of times K set as the updating reference in the overvoltage judgment value updating means 43 is set according to various conditions and various required conditions so that only the overvoltage due to the abnormal disconnection state of the battery 4 can be detected. To be done. The predetermined number of times K is set to, for example, a small value (about several times) if the overvoltage erroneous detection is likely to occur during normal power generation control, and a large value (about several tens times) if it is difficult to occur.

If it is determined in step S204 that the overvoltage occurrence number N is less than or equal to the predetermined number K (that is, NO), the process proceeds to normal step S205, and the overvoltage determination value setting means 40 is broken line in FIG. As described above, the overvoltage determination value Vm is obtained from the sum (VR + ΔV) of the adjustment voltage VR and the margin voltage ΔV.

On the other hand, if it is determined in step S204 that the overvoltage occurrence number N is equal to or greater than the predetermined number K (that is, YES), the overvoltage determination value updating means 43 generates the update signal H, and proceeds to step S206. Therefore,
In step S206, the overvoltage determination value setting means 40 further adds the increment voltage α (for example, about 0.5V) to the sum of the adjustment voltage VR and the margin voltage ΔV to obtain the overvoltage determination value Vm updated to a high value. .

That is, when the number N of times the field current IF is interrupted by the overvoltage detection market number E reaches the predetermined number K or more, the overvoltage is repeated during normal power generation control due to variations in various conditions. Since it indicates that it is detected, the overvoltage determination value Vm is updated to a large value so that the subsequent overvoltage detection signal E is less likely to be generated. As a result, useless power generation stop control can be suppressed.

The values of the margin voltage ΔV in step S205 and the increment voltage α in step S206 differ depending on the system conditions, but they are small enough to promptly detect an overvoltage state, and the normal control is performed. At times, it is set to a large value such that overvoltage is not erroneously detected. As a result, the overvoltage determination value Vm is shown in FIG.
In the disconnection state as shown in (b), the voltage value is set to a level that satisfies the requirement that the electric load 5 is not adversely affected.

Thus, step S205 or S20
After the overvoltage determination value Vm is set in step 6, the process proceeds to step S207, where the voltage comparison unit 41 determines the overvoltage determination value Vm.
m is compared with the rectified output OT2 to determine whether the rectified output OT2 is equal to or higher than the overvoltage determination value Vm.

If the determination result of step S207 is Vm
If ≦ OT2 (that is, YES), the voltage comparison unit 41 determines that the overvoltage state exists, and the overvoltage detection signal E is detected.
To input the overvoltage detection signal E to the field current interruption means 36 and the interruption continuation means 37, and at the same time, the counting means 42.
Is also input, and the process proceeds to step S208.

In step S208, the counting means 42
Determines whether the previous rectified output OT2 is smaller than the overvoltage determination value Vm, and if the previous time is Vm <OT2 (that is, YES), the overvoltage occurrence count (counter value) N is set in step S209. Increment by adding 1. In other words, it is counted as the number of occurrences N when the normal state shifts to the overvoltage state.

Then, in step S210, the interruption continuation means 37 sets the predetermined time To in the overvoltage cut timer TC in response to the overvoltage detection signal E.
The generation of the interruption continuation signal G is continued, and the field current interruption means 3
The interruption control of 6 is continued for a predetermined time To.

Further, in step S211, the field current interruption means 36 generates the interruption signal F in response to the overvoltage detection signal E, stops the operation of the field current control means 34, and turns off the control signal C. , The field switch 11 is turned off. As a result, the field current IF is cut off, the generator 2 enters the power generation stop control state, and the control unit 10
4 ends the processing of FIG.

On the other hand, in step S207, Vm>
If it is determined to be OT2 (that is, NO), step S
Proceeding to 212, the normal state detecting means 38 compares the terminal voltage VB of the battery 4 with the normal determination value Vn (for example, about 12V) and determines whether the terminal voltage VB is equal to or lower than the normal determination value Vn. The normality determination value Vn varies depending on the system conditions, but is set to a value slightly lower than the adjustment voltage VR in consideration of the controllability when returning to the normal power generation control and the margin of the field current interruption control. It

If, in step S212, VB≤
If it is determined to be Vn (that is, YES), the normal state detection means 38 generates the normal detection signal M, and step S21
Go to 3. In step S213, the cutoff releasing means 3
9 generates a release signal P, and in response to the release signal P, the interruption continuation means 37 resets the overvoltage cut timer TC to 0. Further, in step S212, VB> Vn
If it is determined (that is, NO), step S213
Is skipped and the process proceeds to step S214.

Next, in step S214, the interruption continuation means 37 determines whether the value of the overvoltage cut timer TC is larger than 0, and if TC> 0 (that is, YE).
If S), in step S215, the overvoltage cut timer TC is decremented by 1 and decremented, and then the process proceeds to step S211 to continue the interruption control of the field current IF.

In step S214, TC =
If it is determined to be 0 (that is, NO), the interruption continuation means 3
7 turns off the continuation signal G and proceeds to step S216 so that the field current control means 34 performs normal power generation control.

As a result, in step S213,
In response to the normal detection signal M, the overvoltage cut timer TC becomes 0
Resetting to step S216, the normal control is immediately returned to, and the power generation control is restarted while the terminal voltage VB of the battery 4 is sound. Therefore, overshooting or hunting does not occur.

In step S216, the field current control means 34 obtains the deviation between the battery terminal voltage VB and the adjustment voltage VR, and generates the control signal C for the field switch 11 according to this voltage deviation (VB-VR). , The field current IF so that the terminal voltage VB matches the adjustment voltage VR.
Adjust. At this time, the field current IF is controlled by, for example, PWM control for adjusting the duty ratio for turning on the field switch 8. In this way, the processing routine of FIG. 4 is completed, and thereafter, the processing routine of FIG. 4 is repeated at a predetermined cycle.

[0071]

As described above, according to the first aspect of the present invention, the generator having the field coil driven by the engine, the stator coil magnetically coupled to the field coil, and the rectifier for rectifying the AC output of the stator coil. And a battery charged by the rectified output of the generator,
An electric load that receives power from a generator or battery, a field switch that controls the field current that flows in the field coil, various sensors that detect the operating state of the engine, and a field switch that controls the operating state according to the operating state. And a power generation control means for adjusting the rectified output of the generator to control the terminal voltage of the battery to a predetermined regulated voltage, the power generation control means for detecting the terminal voltage of the battery and the operation of the engine. An operating state detecting means for detecting the state, an adjusting voltage setting means for setting an adjusting voltage of the battery according to the operating state, a field current control means for controlling the field switch so that the rectified output matches the adjusting voltage, Rectifying output detection means for detecting the rectified output of the generator, and detecting the overvoltage power generation state when the rectified output shows the overvoltage judgment value or more Overvoltage detection means, field current interruption means for interrupting the field current when an overvoltage power generation state is detected, and field current interruption when the rectified output becomes lower than the overvoltage judgment value after interruption of the field current. In the vehicular power generation control device including a cutoff continuation unit that keeps the cutoff state for a predetermined time, the power generation control unit compares the terminal voltage of the battery with a normal determination value that is lower than the overvoltage determination value during continuous interruption of the field current. And a normal state detecting means for detecting a normal voltage state when the terminal voltage of the battery is equal to or lower than the normal judgment value, and a disconnection releasing means for releasing the interruption of the field current when the normal voltage state is detected. In addition, since the normal power generation control is restarted immediately when the terminal voltage falls below the normal judgment value during the power generation stop control, power generation control at the time of recovery from overvoltage occurrence and normal power generation control Can be optimized, drop in terminal voltage when returning from an overvoltage event, the effect of overshoot and power generation controlling device which prevents the hunting and the like can be obtained.

According to a second aspect of the present invention, in the first aspect, the overvoltage detecting means includes a counting means for counting the number of times the field current interruption control is generated by the overvoltage detection after the engine is started, and the interruption control. When the number of occurrences of the above has reached a predetermined number of times or more, the overvoltage judgment value updating means for updating the overvoltage judgment value to a voltage higher than the previous time is included, and battery deterioration during normal power generation control, temperature and other environments, and regulated voltage Since the operation of the cutoff control due to the erroneous detection of the overvoltage due to the variation in various conditions such as the above is prevented, there is an effect that the vehicular power generation control device with further improved reliability of the overvoltage detection can be obtained.

According to claim 3 of the present invention, in claim 1 or claim 2, the overvoltage detection means includes overvoltage determination value setting means for setting an overvoltage determination value in response to an increase or decrease in the adjustment voltage. Since the margin voltage between the adjustment voltage and the overvoltage determination value is kept large regardless of the increase or decrease of the adjustment voltage, the battery deterioration during normal power generation control,
Effect of preventing malfunction of overvoltage shutoff control due to temperature, other environment, and differences in various conditions such as regulated voltage, etc., and obtaining a vehicle power generation control device that optimizes power generation control at overvoltage occurrence and recovery, and normal power generation control There is.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing a configuration example of power generation control means in Embodiment 1 of the present invention.

FIG. 2 is a functional block diagram showing a configuration example of an overvoltage detection unit in FIG.

FIG. 3 is a characteristic diagram showing the relationship between the adjustment voltage and the overvoltage determination value in the first embodiment of the present invention.

FIG. 4 is a flowchart showing the processing operation of the power generation control means according to the first embodiment of the present invention.

FIG. 5 is a configuration diagram showing a general vehicle power generation control device.

FIG. 6 is a characteristic diagram showing a relationship between an adjustment voltage and an overvoltage determination value in a conventional vehicle power generation control device.

FIG. 7 is an explanatory diagram showing a power supply state for a battery and an electric load of a general generator together with a battery disconnection abnormal state.

[Explanation of reference signs] 1 engine 2 generator 4 battery 5 electric load 8 various sensors 10 control unit 11 field switch 12A power generation control means 21 stator coil 22 field coil 23 rectifier 30 battery voltage detection means 31 operating state detection means 33 adjusted voltage setting means Means 34 Field current control means 32 Rectification output detection means 35 Overvoltage detection means 36 Field current interruption means 37 Interruption continuation means 38 Normal state detection means 39 Interruption cancellation means 40 Overvoltage judgment value setting means 41 Voltage comparison means 42 Counting means 43 Overvoltage Judgment value updating means C Control signal D Operating state E Overvoltage detection signal F Cutoff signal G Continuation signal H Update signal IF Field current K Predetermined number M Normal detection signal N Occurrence number OT1, OT2 Rectified output P Release signal To Predetermined time VB Battery Terminal voltage VR adjustment voltage Vm Overvoltage judgment value Vn Normal judgment value S203 Step for setting adjustment voltage S204 Step for comparing the number of overvoltage occurrences with a predetermined number of times S205 Step for setting a normal overvoltage judgment value S206 Set a higher overvoltage judgment value than the previous time Step S207 Step of comparing rectified output with overvoltage judgment value S208, S209 Step of counting the number of overvoltage occurrences S210, S214, S215 Step of continuing cutoff control for a predetermined time Step S211 Step of cutting off field current S212 Normal judgment value of terminal voltage Step S213 of comparing with S213 Step of returning to normal power generation control S216 Step of executing normal power generation control

Claims (3)

[Claims] 1. A generator having a field coil driven by an engine, a stator coil magnetically coupled to the field coil, and a rectifier for rectifying an AC output of the stator coil, and a rectified output of the generator. A battery, an electric load supplied with electric power from the generator or the battery, a field switch for controlling a field current flowing in the field coil, various sensors for detecting an operating state of the engine, the operating state Power generation control means for controlling the field switch according to the above, adjusting the rectified output of the generator to control the terminal voltage of the battery to a predetermined regulated voltage, the power generation control means comprising the terminal of the battery. Battery voltage detecting means for detecting voltage, and detecting the operating state of the engine Switching state detection means, adjustment voltage setting means for setting the adjustment voltage of the battery according to the operating state, field current control means for controlling the field switch so that the rectified output matches the adjustment voltage, A rectified output detection unit that detects a rectified output of the generator; an overvoltage detection unit that detects an overvoltage power generation state when the rectified output indicates an overvoltage determination value or more; Field current interruption means for interrupting the field current, and interruption continuation means for continuing the interruption state of the field current for a predetermined time when the rectified output becomes lower than the overvoltage determination value after interruption of the field current. In a vehicular power generation control device including a power generation control means, the terminal voltage of the battery is normally lower than the overvoltage determination value during continuous interruption of the field current. A normal state detecting means for detecting a normal voltage state when the terminal voltage of the battery is equal to or lower than the normal determination value by comparing with a determination value; and the field current when the normal voltage state is detected. And a cutoff canceling unit for canceling the cutoff of the power generation control device for a vehicle. 2. The overvoltage detection means counts the number of times the field current interruption control is generated by the overvoltage detection after the engine is started, and when the number of times the interruption control is generated reaches a predetermined number or more. The power generation control device for a vehicle according to claim 1, further comprising: an overvoltage determination value updating unit that updates the overvoltage determination value to a voltage higher than a previous voltage. 3. The vehicular power generation according to claim 1, wherein the overvoltage detection means includes an overvoltage determination value setting means for setting the overvoltage determination value in response to an increase or decrease in the adjustment voltage. Control device.