JP6844924B2 - Battery charger - Google Patents

Description

The present invention relates to a battery charging device that compares the detection voltage of a battery mounted on a vehicle with each of a plurality of predetermined voltage thresholds to determine the degree of deterioration of the battery and controls charging / discharging of the battery according to the degree of deterioration. ..

When performing charge / discharge control of the battery mounted on the vehicle, the deterioration state of the battery is determined, and if it is not deteriorated, the power generation suppression control is performed, while if it is deteriorated, the power generation suppression control is released. It has been proposed to prevent insufficient charging when the battery is charged with the same current as before deterioration (Patent Document 1).

JP 2011-130620 (see paragraphs 0005, 0035-0036, FIG. 4).

In this way, as a conventional device that performs charge / discharge control according to the deterioration state of the battery, a voltage detecting means for detecting the voltage of the battery mounted on the vehicle and a plurality of different voltages for determining the degree of deterioration of the battery. It is provided with a storage means for storing the threshold value and a determination means for determining the degree of deterioration of the battery by comparing the voltage detected by the voltage detecting means immediately after starting the engine with each of the plurality of voltage thresholds stored in the storage means. There is a method in which the degree of deterioration of the battery is determined by a determination means, and the charging / discharging of the battery is controlled according to the determined degree of deterioration.

By the way, when the vehicle is a new vehicle, the starter motor for starting the engine is new and its internal resistance fluctuates greatly. Therefore, when the ignition switch is turned on and the starter motor is driven by a battery for cranking. In addition, the drop in battery voltage immediately after the ignition switch is turned on or during the disconnection operation from the crank shaft of the starter motor becomes much larger than in the case of a non-new car, and the degree of deterioration progresses due to the large drop in battery voltage. It may be judged that the voltage detected by the voltage detecting means is lower than the voltage threshold that is the criterion for determining that the battery is present, and it is mistaken that the battery is deteriorated and should be charged even though the battery is not deteriorated. It may be judged.

INDUSTRIAL APPLICABILITY When determining the degree of deterioration of a battery based on the detected voltage of the battery, it is possible to prevent erroneous determination that the battery is deteriorated even though the battery is not deteriorated when the vehicle is a new vehicle. The purpose is to do so.

In order to achieve the above object, the battery charging device of the present invention stores a voltage detecting means for detecting the voltage of a battery mounted on a vehicle and a plurality of different voltage thresholds for determining the degree of deterioration of the battery. The storage means is provided with a determination means for determining the degree of deterioration of the battery by comparing the voltage detected by the voltage detecting means immediately after the engine is started with each of the plurality of voltage thresholds stored in the storage means. A battery charging device that controls charge / discharge of a battery according to the degree of deterioration of the battery, which is determined by a determination means, and detects whether or not the cranking state at the time of starting the engine has reached a predetermined predetermined state. The storage means includes a ranking detecting means, and the storage means includes a first voltage threshold group when the cranking state at the time of starting the engine reaches the predetermined state, and a voltage threshold group when the cranking state does not reach the predetermined state. The second voltage threshold group whose level is set lower than that of the first voltage threshold group is stored, and the determination means has not reached the predetermined state by the cranking detecting means. When it is detected, the second voltage threshold group is read from the storage means, and each voltage threshold of the read second voltage threshold group is compared with the detected voltage by the voltage detecting means. When it is detected that the ranking state has reached the predetermined state, the first voltage threshold group is read from the storage means, and each voltage threshold of the read first voltage threshold group and the voltage detection. It is characterized by comparing with the voltage detected by the means.

According to the present invention, for example, when the cranking time or the number of times of cranking is detected as a cranking state, if the cranking time is short or the number of times of cranking is small, it is determined that the vehicle is a new vehicle. Since there is no problem, when the cranking detection means detects that the cranking state has not reached the predetermined state (predetermined time or predetermined number of times), it can be determined that the vehicle is a new vehicle, and the vehicle is stored by the determination means. A second voltage threshold group is read from the means, and each voltage threshold of the read second voltage threshold group is compared with the voltage detected by the voltage detecting means. On the other hand, when it is detected by the cranking detecting means that the cranking state has reached a predetermined state (a predetermined time or a predetermined number of times), it can be determined that the vehicle is not a new vehicle. The first voltage threshold group is read, and each voltage threshold of the read first voltage threshold group is compared with the voltage detected by the voltage detecting means.

At this time, since the second voltage threshold group corresponding to the case where the vehicle is a new vehicle is set to a lower level than the first voltage threshold group corresponding to the case where the vehicle is not a new vehicle, the cranking state is in a predetermined state. In other words, the voltage threshold that is the reference for deterioration judgment when the vehicle is a new vehicle is switched to a low level, and the voltage threshold of the second voltage threshold group at a low level and the voltage detected by the voltage detecting means. As a feature of the new car, even if the voltage detected by the battery drops significantly immediately after the ignition switch is turned on, the voltage detected by the voltage detecting means can be prevented from becoming lower than the voltage threshold of the second voltage threshold group. This makes it possible to prevent the battery from being erroneously determined to be deteriorated even though the battery has not deteriorated.

It is a block diagram of one Embodiment of the battery charging device which concerns on this invention. It is an operation explanatory view of FIG. It is a flowchart for operation explanation of FIG.

An embodiment of the battery charging device according to the present invention will be described in detail with reference to FIGS. 1 to 3.

The battery charging device 1 is configured as shown in FIG. That is, the voltage detecting means 3 for detecting the voltage of the battery 2 mounted on the vehicle, the cooling water temperature detecting sensor 4 for detecting the engine water temperature T which is the temperature of the engine cooling water, the ignition switch 5 for turning the engine on and off, and the ignition switch 5. The engine ECU (Electronic Control Unit) 6 for controlling the operation of the engine is provided, and the engine EUC 6 controls the charging / discharging means 7 composed of an alternator according to the degree of deterioration of the battery 2 to control the charging / discharging of the battery 2.

As shown in FIG. 1, the engine ECU 6 includes a storage means 6a composed of RAMs that store a plurality of different voltage thresholds in order to determine the degree of deterioration of the battery 2, and a voltage detecting means immediately after the engine is started by turning on the ignition switch 5. The determination means 6b for determining the degree of deterioration of the battery 2 by comparing the detection voltage detected by 3 with each of the plurality of voltage thresholds stored in the storage means 6a, and the number of cranking states as the cranking state at the time of starting the engine. It is provided with a cranking count detecting means 6c (corresponding to the "cranking detecting means" in the present invention) for detecting whether or not K has reached a preset predetermined number of times Kt (corresponding to the "predetermined state" in the present invention). ..

The storage means 6a has a first voltage threshold group when the number of cranking times K at the time of starting the engine has reached a predetermined number of times Kt (for example, 2000 times), and a level lower than the first voltage threshold group. The second voltage threshold group when the set predetermined number of times has not been reached is stored. Here, it is desirable to experimentally obtain the number of cranking times when the internal resistance of the starter motor becomes stable when the ignition switch is turned on and the starter motor is driven with the predetermined number of times Kt. ..

In this way, by determining whether or not the ranking number K at the time of starting the engine has reached the predetermined number Kt, there are cases where the internal resistance of the starter motor fluctuates greatly and is not stable, as in a new car, and a starter instead of a new car. It is possible to distinguish the case where the internal resistance of the motor is stable.

At this time, to give an example of each voltage threshold value of the first and second voltage threshold value groups stored in the storage means 6a, in order to correspond to the state of the battery voltage drop immediately after the ignition switch 5 is turned on when the vehicle is not a new vehicle. For example, 8.5V as the reference threshold THV1a of the deterioration level 1 and 8V as the reference threshold THV2a of the deterioration level 2 are stored as the first voltage threshold group, and immediately after the ignition switch 5 is turned on in the case of a new vehicle. For example, 7.8V is stored as the reference threshold THV1b of the deterioration level 1 and 7.2V is stored as the reference threshold THV2b of the deterioration level 2 as the second voltage threshold group. Will be done.

Further, as a threshold value THC1a that serves as a reference for deterioration level 1 in response to a drop in battery voltage during the separation operation of the starter motor from the crank shaft in cranking when the vehicle is not a new vehicle, for example, 10.1 V, deterioration level 2 For example, 9.8V as the reference threshold THC2a is stored in the storage means 6a as the first voltage threshold group, and corresponds to the drop state of the battery voltage during the disconnection operation from the crank shaft of the starter motor in the case of a new vehicle. For example, 9.8 V as the reference threshold THC1b of the deterioration level 1 and 9.6 V as the reference threshold THC2b of the deterioration level 2 are stored in the storage means 6a as the second voltage threshold group.

By the way, since the degree of drop in the battery voltage at the time of starting the engine differs depending on whether or not the engine water temperature T detected by the cooling water temperature detection sensor 4 when the engine is warmed is, for example, 70 ° C. or lower, it is stored in the storage means 6a. The first and second voltage threshold groups include a voltage threshold when the engine is not warmed and the engine water temperature T is 70 ° C. or lower, and a voltage threshold when the engine is sufficiently warmed and the engine water temperature T is higher than 70 ° C. The voltage threshold is stored in the storage means 6a.

That is, when the above-mentioned thresholds THV1a, THV2a, THC1a, and THC2a are stored as the first voltage threshold group when the engine is not warm and the engine water temperature T is 70 ° C. or lower even when the vehicle is not a new vehicle. In addition, as the voltage threshold when the engine is sufficiently warmed and the engine water temperature T is higher than 70 ° C, the standard of deterioration level 1 for dealing with the drop state of the battery voltage immediately after the ignition switch 5 is turned on when the vehicle is not a new car is used. The threshold value THV11a, the threshold value THV12a which is the reference for the deterioration level 2, and the reference for the deterioration level 1 for dealing with the drop state of the battery voltage during the separation operation from the crank shaft of the starter motor in cranking when the vehicle is not a new vehicle. The threshold value THC11a and the threshold value THC12a as a reference for the deterioration level 2 are also stored as the first voltage threshold value group.

Further, when the above-mentioned thresholds THV1b, THV2b, THC1b, and THC2b are stored as the second voltage threshold group when the engine is not warmed and the engine water temperature T is 70 ° C. or lower even in the case of a new vehicle. In addition to these, as a voltage threshold value when the engine is sufficiently warmed and the engine water temperature T is higher than 70 ° C., the deterioration level 1 for dealing with the drop state of the battery voltage immediately after the ignition switch 5 is turned on in the case of a new car. The threshold value THV11b, which is the reference for The threshold THC11b that serves as a reference for level 1 and the threshold value THC12b that serves as a reference for deterioration level 2 are also stored as a second voltage threshold group. The maps of the first and second voltage threshold groups stored in the storage means 6a are as shown in FIG.

When the engine water temperature T is 70 ° C. or lower as a reference threshold of the deterioration level 3 for determining that the deterioration of the battery 2 is the worst state in the state where the battery voltage drops immediately after the ignition switch 5 is turned on. The threshold value TH3 (for example, 6.5V) of is stored in the storage means 6a in common in the case of a new car and a non-new car, and the battery 2 is deteriorated during the separation operation of the starter motor from the crankshaft in cranking. As a threshold value that serves as a reference for deterioration level 3 for determining that is in the worst state, the threshold value TH4 (for example, 8.2V) when the engine water temperature T is higher than 70 ° C. is common to both new cars and non-new cars. It is stored in the storage means 6a.

When the determination means 6b described above determines that the cranking count K at the time of engine start detected by the cranking count detecting means 6c has not reached the predetermined number Kt, it determines that the vehicle is a new vehicle and stores the storage means 6a. The voltage threshold of the second voltage threshold group (see FIG. 2) is read from, and each voltage threshold of the read second voltage threshold group is compared with the voltage detected by the voltage detecting means 3, while the cranking count detecting means. When it is determined that the number of cranking times K at the time of starting the engine detected by 6c has reached the predetermined number of times Kt, it is determined that the vehicle is not a new vehicle, and the storage means 6a to the first voltage threshold group (see FIG. 2). The voltage threshold is read out, and each voltage threshold of the read first voltage threshold group is compared with the battery voltage detected by the voltage detecting means 3.

Further, whether or not the engine water temperature T detected by the cooling water temperature detection sensor 4 by the determination means 6b is 70 ° C. or lower from the voltage thresholds of the first and second voltage threshold groups read from the storage means 6a. The voltage threshold corresponding to is selected. For example, when the engine water temperature T is 70 ° C. or lower and the vehicle is not a new vehicle, the thresholds THV1a, THV2a, THC1a, and THC2a of the first voltage threshold group are selected and read, and the engine water temperature T is higher than 70 ° C. and the vehicle is not a new vehicle. The thresholds THV11a, THV12a, THC11a, and THC12a of the first voltage threshold group are selected and read out. Further, the threshold value TH3 or TH4, which is a criterion for determining the deterioration level 3, is read out depending on whether or not the engine water temperature T is 70 ° C. or lower.

On the other hand, when the engine water temperature T is 70 ° C. or lower and the vehicle is new, the thresholds THV1b, THV2b, THC1b, THC2b of the second voltage threshold group are selected and read, and the engine water temperature T is higher than 70 ° C. in the new vehicle. In some cases, the thresholds THV11b, THV12b, THC11b, THC12b of the second voltage threshold group are selected and read out. Further, the threshold value TH3 or TH4, which is a criterion for determining the deterioration level 3, is read out depending on whether or not the engine water temperature T is 70 ° C. or lower.

Next, the determination process of the determination means 6b will be described with reference to the flowchart of FIG. In FIG. 3, it is determined by the determining means 6b whether or not the cranking number K detected by the cranking number detecting means 6c has reached the predetermined number Kt (step S1), and the determination result is NO, that is, the vehicle is The case where it is determined to be a new vehicle is shown, and when it is determined that the vehicle is a new vehicle, it is subsequently determined by the cooling water temperature detection sensor 4 whether or not the engine water temperature T is 70 ° C. or lower (step). S2) If the engine water temperature T is 70 ° C. or lower and the determination result is YES, it is assumed that the vehicle is a new vehicle, and the processes of steps S3 and S11 are performed in parallel.

That is, according to the determination means 6b, the thresholds THV1b, THV2b, THC1b, THC2b and corresponding to the engine water temperature T of 70 ° C. or lower are selected from the second voltage threshold group (see FIG. 2) when the storage means 6a is a new vehicle. The thresholds TH3 and TH4 are selected and read, and the battery voltage VBS detected by the voltage detecting means 3 in the state where the battery voltage drops immediately after the ignition switch 5 is turned on by the determining means 6b is read out as the threshold THV1b. It is determined whether or not it is as follows (step S3), and if this determination result is NO, the operation is terminated as the battery 2 is not deteriorated, and if the determination result in step S3 is YES, voltage detection is performed. It is determined whether or not the battery voltage VBS detected by the means 3 is equal to or less than the read threshold THV2b (<THV1b) (step S4), and if this determination result is NO, the battery 2 has a deterioration level of 1. (That is, it is determined that the state is slightly deteriorated (step S5), and then the operation ends.

On the other hand, if the determination result in step S4 is YES, it is determined whether or not the battery voltage VBS detected by the voltage detecting means 3 is equal to or less than the read threshold value TH3 (<THV2b) (step S6). If the determination result is NO, the operation is terminated after the battery 2 is determined to be in the deterioration level 2 state (step S7), and if the determination result in step S6 is YES, the battery 2 is severely deteriorated. It is determined that the deterioration level is 3 (step S8), and then the operation ends.

Further, in the process of step S11 performed in parallel with step S3 described above, the battery voltage VBC detected by the voltage detecting means 3 during the separation operation from the crankshaft of the starter motor in cranking is determined by the determining means 6b. , It is determined whether or not the read threshold is THC1b or less (step S11), and if this determination result is NO, the operation is terminated assuming that the battery 2 has not deteriorated, and the determination result in step S11 is If YES, it is determined whether or not the battery voltage VBC detected by the voltage detecting means 3 is equal to or less than the read threshold THC2b (<THC1b) (step S12), and if this determination result is NO. , The battery 2 is determined to be in a state of deterioration level 1, that is, slightly deteriorated (step S13), and then the operation ends.

If the determination result in step S12 is YES, it is determined whether or not the battery voltage VBC detected by the voltage detecting means 3 is equal to or less than the read threshold TH4 (<THC2b) (step S14). If the determination result is NO, the operation ends after the battery 2 is determined to be in the deterioration level 2 state (step S15), and if the determination result in step S14 is YES, the battery 2 is severely deteriorated. It is determined that the deterioration level is 3 (step S16), and then the operation ends.

By the way, as a result of the determination in step S2 described above, if it is determined that the engine water temperature T is higher than 70 ° C. and the determination result is NO, the processes of steps 21 and 31 similar to those in steps S3 and S11 are performed in parallel. It is done.

That is, according to the determination means 6b, the threshold values THV11b, THV12b, THC11b, corresponding to the case where the engine water temperature T is higher than 70 ° C. from the second voltage threshold group (see FIG. 2) when the storage means 6a is a new vehicle. THC12b and thresholds TH3 and TH4 were selected and read, and the determination means 6b read the battery voltage VBS detected by the voltage detecting means 3 in the state where the battery voltage dropped immediately after the ignition switch 5 was turned on. It is determined whether or not the threshold value is THV11b or less (step S21), and if this determination result is NO, the operation is terminated as the battery 2 is not deteriorated, and if the determination result in step S21 is YES, it is determined. It is determined whether or not the read threshold value is THV12b (<THV11b) or less (step S22), and if the determination result is NO, it means that the battery 2 is in the state of deterioration level 1, that is, slightly deteriorated. It is determined (step S23), and then the operation ends.

On the other hand, if the determination result in step S22 is YES, it is determined whether or not the battery voltage VBS detected by the voltage detecting means 3 is equal to or less than the read threshold TH3 (<THV12b) (step S24). If the determination result is NO, the operation ends after the battery 2 is determined to be in the deterioration level 2 state (step S25), and if the determination result in step S24 is YES, the battery 2 is severely deteriorated. It is determined that the deterioration level is the worst (step S26), and then the operation ends.

Further, in the process of step S31 performed in parallel with step S21 described above, the battery voltage VBC detected by the voltage detecting means 3 during the separation operation from the crankshaft of the starter motor in the cranking by the determining means 6b is obtained. , It is determined whether or not the read threshold is THC11b or less (step S31), and if this determination result is NO, the operation is terminated assuming that the battery 2 has not deteriorated, and the determination result in step S31 is If YES, it is determined whether or not the battery voltage VBC detected by the voltage detecting means 3 is equal to or less than the read threshold THC12b (<THC11b) (step S32), and if this determination result is NO. , The battery 2 is determined to be in the state of deterioration level 1, that is, slightly deteriorated (step S33), and then the operation ends.

If the determination result in step S32 is YES, it is determined whether or not the battery voltage VBC detected by the voltage detecting means 3 is equal to or less than the read threshold TH4 (<THC12b) (step S34). If the determination result is NO, the operation ends after the battery 2 is determined to be in the deterioration level 2 state (step S35), and if the determination result in step S34 is YES, the battery 2 is severely deteriorated. It is determined that the deterioration level is 3 (step S36), and then the operation ends.

By the way, as a result of the determination in step S1 described above, when it is determined that the cranking count K detected by the cranking count detecting means 6c has reached the predetermined number Kt and the vehicle is not a new vehicle, the step shown in FIG. After shifting to S41, a judgment process other than a new vehicle is performed. The determination process of step S41 is performed in almost the same procedure as steps S3 to S8, steps S11 to S16, steps S21 to S26, and steps S31 to S36 in the processes after step S2, but the storage means. Processing is performed using each voltage threshold value of the first voltage threshold value group corresponding to the case where the vehicle is not a new vehicle stored in 6a.

That is, the comparison in step S3 is not the threshold THV1b but the threshold THV1a of the first voltage threshold group, the comparison in step S4 is not the threshold THV2b but the threshold THV2a of the first voltage threshold group, and the comparison of step S11 is the threshold THC1b. The comparison of the threshold THC1a of the first voltage threshold group and the step S12 is not the threshold THC2b, but the threshold THV2a of the first voltage threshold group, and the comparison of step S21 is not the threshold THV11b but the threshold THV11a of the first voltage threshold group. The comparison of S22 is not the threshold THV12b but the threshold THV12a of the first voltage threshold group, the comparison of step S31 is not the threshold THC11b but the threshold THC11a of the first voltage threshold group, and the comparison of step S32 is not the threshold THC12b but the first voltage. The difference is that it is the threshold THC12a of the threshold group, and detailed description thereof will be omitted.

Therefore, according to the above-described embodiment, the second voltage threshold group stored in the storage means 6a corresponding to the case where the vehicle is a new vehicle is at a higher level than the first voltage threshold group corresponding to the case where the vehicle is not a new vehicle. Is set low, so when cranking by turning on the ignition switch 5, if the cranking count K detected by the cranking count detecting means 6c does not reach the predetermined number Kt, the degree of deterioration of the battery 2 The voltage threshold that serves as a judgment criterion is switched to a lower level, and by comparing the voltage threshold of the lower level second voltage threshold group with the battery voltage detected by the voltage detecting means 3, the new car As a feature, even if the detection voltage of the battery 2 immediately after the ignition switch 5 is turned on drops significantly, it is possible to prevent the voltage detected by the voltage detecting means 3 from becoming lower than the voltage threshold of the second voltage threshold group, and the battery 2 can be used. Although it is not deteriorated, it is possible to prevent the battery 2 from being erroneously determined to be deteriorated, and the charging / discharging means 7 can appropriately control the charging / discharging of the battery 2. It is possible to extend the life of 2.

The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention.

For example, in the embodiment to be described above, as a cranking state for determining whether the vehicle is a new vehicle, the cranking count K detected by the cranking count detecting means 6c is compared with a preset predetermined number Kt. However, a cranking detection means capable of detecting the cranking time is provided, the cranking time detected by the cranking detection means is compared with a preset predetermined time, and the detected cranking time is longer than the predetermined time. It may be short and it may be determined that the vehicle is a new vehicle.

2 ... Battery 3 ... Voltage detection means 6 ... Engine ECU
6a ... Memory means 6b ... Judgment means 6c ... Cranking count detection means (cranking detection means)

Claims (1)

A voltage detecting means for detecting the voltage of a battery mounted on a vehicle, a storage means for storing a plurality of different voltage thresholds for determining the degree of deterioration of the battery, and a voltage detected by the voltage detecting means immediately after starting the engine. A determination means for determining the degree of deterioration of the battery by comparing each of the plurality of voltage thresholds stored in the storage means is provided, and the battery is charged according to the degree of deterioration of the battery determined by the determination means. A battery charging device that controls discharge
It is equipped with a cranking detecting means for detecting whether or not the cranking state at the time of starting the engine has reached a predetermined predetermined state.
The storage means
A first voltage threshold group when the cranking state at the time of starting the engine has reached the predetermined state, and a voltage threshold group when the cranking state has not reached the predetermined state, which is larger than the first voltage threshold group. Stores a second voltage threshold group with a low level,
The judgment means is
When it is detected by the cranking detecting means that the cranking state has not reached the predetermined state, the second voltage threshold group is read from the storage means, and the read second voltage threshold group is read. Each voltage threshold is compared with the voltage detected by the voltage detecting means, and when it is detected that the cranking state has reached the predetermined state, the first voltage threshold group is read from the storage means. A battery charging device for comparing each of the read out voltage thresholds of the first voltage threshold group with the voltage detected by the voltage detecting means.

Images