JP5196746B2 - Fan drive control method and battery overheat protection device in battery overheat protection device - Google Patents

Description

  The present invention relates to a fan drive control method and apparatus used for a battery overheat protection device, and more particularly, to a power supply for a drive motor for a drive wheel in a hybrid vehicle or the like, compared with overcharge or overdischarge. The present invention relates to an improvement in reliability of overheat protection for a battery that is likely to be in a high overheat state, simplification of configuration, and the like.

In so-called hybrid vehicles, the battery used to supply power to the drive motor for the drive wheels has a higher voltage than that of a conventional gasoline engine vehicle or the like, and is therefore overcharged or overdischarged for some reason. In such a case, if the liquid is abnormally overheated and left unattended, there is a possibility that the electrolyte solution may be ejected in the worst case.
In consideration of the characteristics of the battery used in such a hybrid vehicle, the hybrid vehicle generally has a configuration in which a dedicated fan for cooling the battery is provided. Such a fan failure for cooling the battery accelerates the abnormal overheating of the battery described above. Therefore, various battery overheat protection devices that take into account a fan failure determination have been proposed. .

  For example, a cooling fan is provided in which the air volume is controlled according to the battery temperature, and the cooling fan is based on the difference between the calculated estimated temperature change of the battery and the actual temperature change calculated from the actual battery temperature. It has been proposed to determine the failure of the cooling fan, and when it is determined to be a failure, a device configured to limit the use of the cooling fan has been proposed (see, for example, Patent Document 1).

JP 2001-86601 A (page 3-7, FIGS. 1 to 4)

By the way, in the conventional device disclosed in the above-mentioned Patent Document 1 or the like, the rotation speed of the cooling fan is, for example, output from the battery control device as a speed control signal by PWM or the like according to the desired rotation speed for the cooling fan. The structure is such that the rotational speed of the cooling fan is determined according to the signal.
Therefore, in such a configuration, if the electrical wiring between the battery control device and the cooling fan is disconnected for some reason, or if it is short-circuited to the ground, the cooling fan is at the maximum rotational speed or is not rotating. Will be taken.

  However, the maximum rotation speed state and the rotation stop state as described above are not related to the operation state of the battery, that is, in other words, independent of the temperature state of the battery. On the other hand, since the rotation stop state causes the temperature of the battery to rise, it should be avoided as much as possible except when necessary, and the maximum rotation speed state may require a cooling fan in some cases. In order to achieve the above driving state, it should be kept to the minimum necessary. That is, in the conventional apparatus, when the speed control signal to the cooling fan is abnormal, the cooling fan is not necessarily considered to be driven appropriately.

The present invention has been made in view of the above circumstances, and provides a fan drive control method and a battery overheat protection device in a reliable battery overheat protection device that can reliably prevent abnormal overheating of the battery with a simple configuration. It is to provide.
Another object of the present invention is to provide a fan drive control method and a battery overheat protection device in a battery overheat protection device that can reliably prevent the battery from reaching a worst state due to abnormal overheating.

In order to achieve the object of the present invention, a fan drive control method in a battery overheat protection device according to the present invention has a fan for battery cooling, and a speed control signal for setting the rotation speed of the fan is externally supplied. is input, the fan with is driven and controlled in rotation speed based on the speed control signal, either before Symbol speed control signal is in a first abnormal state equivalent to a short circuit state of the transmission path, or, the rate It is detected whether the control signal is in a second abnormal state equivalent to the open state of the transmission line, and if the speed control signal is detected in the first abnormal state, the fan is while driving at a rotational speed, when that speed control signal is in the second abnormal state is detected, the battery overheat protection device consisting configured to drive the fan at a predetermined rotational speed Kicking a fan drive control method,
The speed control signal has a proportional relationship between the index value and the rotation speed of the fan, and the fan operating range and the stop range are adjacent to the index value along the increasing direction of the index value in advance. On the other hand, the first outside of the first range is set on the opposite side of the operation range and adjacent to the stop range, the second on the opposite side of the stop range and adjacent to the operation range. When the out-of-range is set and it is detected that the index value is out of the first range, the speed control signal is assumed to be in the first abnormal state, while the index value is out of the second range. When it is detected that the speed control signal is in the second abnormal state, it is assumed that the speed control signal is in the second abnormal state, and the fan is driven to the rotational speed corresponding to each state .
In such a configuration, the speed control signal is a repetitive pulse signal with a variable repetition period and a variable pulse width whose pulse width is changed according to a desired fan rotation speed, and the speed control signal has a duty of 0%. It is preferable that the state is determined to be the first abnormal state, and the speed control signal is determined to be the second abnormal state when the duty is 100%.
The speed control signal assumes that the duty is an index value, and when it is detected that the index value is equal to or less than a first predetermined value, the speed control signal presumes that the speed control signal is in the first abnormal state, When it is detected that the index value is greater than or equal to the second predetermined value, the speed control signal is assumed to be in the second abnormal state, and the fan is driven to the rotational speed corresponding to each state. More preferred.
Further, when it is detected that the speed control signal is in the first abnormal state or the second abnormal state, the outside is informed that the fan drive state is in the abnormal state. Is preferred.
In order to achieve the object of the present invention, a battery overheat protection device according to the present invention includes:
A fan for cooling the battery is provided, a speed control signal for setting the rotational speed of the fan is input from the outside, and the fan is driven and controlled to a rotational speed based on the speed control signal. with a drive circuit for controlling the energization of the motor for driving the front Symbol fan, a control signal for controlling the operation of the drive circuit on the basis of said speed control signal and a motor controller to be output to the driving circuit Become
The motor control unit is in a first abnormal state in which the speed control signal is equivalent to a short circuit state of the transmission line, or a second abnormal state in which the speed control signal is equivalent to an open state of the transmission line. When the speed control signal is detected to be in the first abnormal state, the operation of the drive circuit is controlled so that the fan is driven at a predetermined rotational speed. A battery overheat configured to control the operation of the drive circuit so that the fan is driven at a predetermined rotational speed even when the speed control signal is detected to be in the second abnormal state. A protective device,
The speed control signal has a proportional relationship between the index value and the rotation speed of the fan, and is predetermined so that the operation range and the stop range of the fan are adjacent to the index value, while adjacent to the operation range, And outside the first range is set on the opposite side of the stop range, adjacent to the stop range, and outside the second range is set on the opposite side of the operation range,
When the motor control unit detects that the index value is out of the first range, the motor control unit assumes that the speed control signal is in the first abnormal state, while the index value is out of the second range. Is detected, the speed control signal is assumed to be in the second abnormal state, and the operation of the drive circuit is controlled so that the fan is driven at a rotational speed corresponding to each state. Is.
In such a configuration, the speed control signal is a repetitive pulse signal with a variable repetition period and a variable pulse width whose pulse width is changed according to a desired fan rotation speed, and the speed control signal has a duty of 0%. It is preferable that the state is determined to be the first abnormal state, and the speed control signal is determined to be the second abnormal state when the duty is 100%.
The speed control signal uses the duty as an index value,
When the motor control unit detects that the index value is less than or equal to the first predetermined value, the motor control unit presumes that the speed control signal is in the first abnormal state, while the index value is greater than or equal to the second predetermined value. If detected, the speed control signal is assumed to be in the second abnormal state, and the operation of the drive circuit is controlled so that the fan is driven at a rotational speed corresponding to each state. Those are also suitable.
Furthermore, when the motor control unit detects that the speed control signal is in the first abnormal state or the second abnormal state, it notifies the outside that the fan drive state is in the abnormal state. Such a configuration is also suitable.

According to the present invention, whether or not the signal for setting the rotation speed of the cooling fan input from the outside to the battery overheat protection device is equivalent to an open or short state of the wiring that performs the transmission. If any one of them is detected, it is assumed that the speed control signal is abnormal, and the cooling fan is set to a predetermined operating state according to each, so the speed control signal is abnormal. Even in this state, the cooling fan for overheating protection of the battery can be driven appropriately, and highly reliable battery overheating protection can be realized without bringing the battery into the worst state.
In particular, it can be realized by adding procedures such as processing to determine abnormalities in the speed control signal to a program in an existing control unit using a microcomputer provided for driving control of the cooling fan. Thus, it is possible to realize reliable fan drive control of the battery overheat protection device.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6.
The members and arrangements described below do not limit the present invention and can be variously modified within the scope of the gist of the present invention.
First, a configuration example of the battery protection device according to the embodiment of the present invention will be described with reference to FIG.
This configuration example is particularly suitable for overheating protection of a battery (not shown) used for supplying power to a drive motor for driving wheels in a hybrid vehicle. The battery overheat protection device S according to the embodiment of the present invention includes a motor control unit (indicated as “MOT-CON” in FIG. 1) 102, a drive circuit (indicated as “DRV” in FIG. 1) 103, and an illustration. The cooling fan 1 provided in the vicinity of the battery that is not used is configured as a main component.

  The motor control unit 102 generates and outputs a control signal for the drive circuit 103 having a transistor (not shown) as a main component based on a speed control signal from the main control unit 101 described later, as will be described later. A fan drive control processing program in a battery overheat protection device is executed. The motor control unit 102 includes a microcomputer, a storage element, an interface circuit, and the like.

The drive circuit 103 has a known and well-known circuit configuration that controls energization of the drive motor 1a of the cooling fan 1 using, for example, a transistor (not shown) as a main component. This drive circuit 103 controls conduction and non-conduction of a transistor (not shown) of the drive circuit 103 in accordance with a duty of a speed control signal input from the main control unit 101 described later to the motor control unit 102. The control signal is input from the motor control unit 102. The drive circuit 103 is supplied with power from the auxiliary battery 3.
In the embodiment of the present invention, the rotational speed control of the driving motor 1a is known and well-known PWM control, and the speed is adjusted so that the driving motor 1a has a rotational speed corresponding to the duty of the speed control signal. The drive is controlled by the motor control unit 102 and the drive circuit 103 based on the control signal.

  A main control unit (indicated as “M-CONT” in FIG. 1) 101 executes a control program for determining the rotation speed of the cooling fan 1, and rotates the drive motor 1a based on data such as battery temperature (not shown). A speed control signal, which is a PWM signal for determining the speed, is generated and output. The main control unit 101 includes a microcomputer, a storage element, an interface circuit, and the like. In addition to having the function of generating and outputting the speed control signal as described above, the main control unit 101 is an electronic device necessary for running control of the hybrid vehicle. It has a function to execute control.

  In the embodiment of the present invention, the main control unit 101 and the motor control unit 102 are connected by a signal harness (electrical wiring) 2. In this signal harness 2, at least one end, that is, in the configuration example shown in FIG. 1, the end on the motor control unit 102 side is connected to the connector 4 provided in the vicinity of the motor control unit 102. The motor control unit 102 can be electrically connected via the connector 4. The speed control signal is transmitted via the signal harness 2.

Specifically, for example, a brushless motor or the like is used as the driving motor 1a, but it is not necessary to be limited to this.
Further, it is preferable that the motor control unit 102, the drive circuit 103, and the drive motor 1a are unitized and integrated and arranged near a battery (not shown).
The main control unit 101 and the motor control unit 102 are supplied with power through a power supply circuit (not shown) that converts the voltage of the auxiliary battery 3 into a desired voltage.

FIG. 2 shows a procedure of fan drive control processing in the battery overheat protection device executed by the motor control unit 102, and the contents thereof will be described below with reference to FIG.
When the process is started, it is determined whether or not the signal harness 2 to which the speed control signal is transmitted is in an open state (see step S100 in FIG. 2). Here, the signal harness 2 is in an open state when the signal harness 2 is disconnected at the connector 4 or when the signal harness 2 is disconnected at the main control unit 101 side. Means a case where a disconnection occurs in the middle.

  In the embodiment of the present invention, the speed control signal is a so-called variable duty pulse signal whose pulse width is changed according to the desired rotation speed of the cooling fan 1 with a constant repetition period. The speed control signal is output from a so-called open collector type circuit in the main control unit 101, and a predetermined power supply voltage is applied in the motor control unit 102, so that the signal harness 2 is opened. In this state, on the motor main control unit 101 side, the speed control signal substantially corresponds to the above-described predetermined power supply voltage value, in other words, the logical value High. That is, in other words, a state equivalent to a state in which the duty as the index value of the speed control signal is 100% is obtained. Therefore, in such a state, the motor control unit 102 can determine that the speed control signal is equivalent to the open state of the signal harness 2. In the following description, it is assumed that “the signal harness 2 is open” and “the speed control signal is open” are equivalent.

In this manner, when it is determined in step S100 that the signal harness 2 is in the open state (in the case of YES), it is determined whether or not a predetermined time has elapsed (see FIG. 2). If it is determined that the predetermined time has elapsed (in the case of YES), the fail safe operation of the cooling fan 1, that is, the fail safe operation of the drive motor 1a (details will be described later). Is executed (see step S114 in FIG. 2).
On the other hand, if it is determined in step S102 that the predetermined time has not elapsed (in the case of NO), the process proceeds to step S104 described later. Here, the predetermined time is determined when the signal harness 2 is suddenly opened only for a relatively short period of time when the signal harness 2 is not open and is reliable. Only for fail-safe operation.

  On the other hand, if it is determined in step S100 that the signal harness 2 is not in the open state (in the case of NO), the process proceeds to step S104, and whether or not the signal harness 2 is in the short state. Is determined. Here, the signal harness 2 being in a short state means that the signal harness 2 is connected to the ground at some point for some reason. In the embodiment of the present invention, as described above, since the speed control signal is output from a so-called open collector type circuit in the main control unit 101, the signal harness 2 is short-circuited. In the motor control unit 102, the speed control signal is received in a state substantially corresponding to the ground potential, in other words, the logical value Low. That is, in this case, the duty as the index value of the speed control signal is equivalent to 0%. Therefore, when the speed control signal is in such a state, the motor control unit 102 can determine that the speed control signal is equivalent to the short state of the signal harness 2. In the following description, it is assumed that “the signal harness 2 is in a short state” and “the speed control signal is in a short state” have the same meaning.

When it is determined in step S104 that the signal harness 2 is in a short state (in the case of YES), it is determined whether or not a predetermined time has elapsed (see step S106 in FIG. 2). When it is determined that the predetermined time has elapsed (in the case of YES), the fail safe operation of the cooling fan 1, that is, the fail safe operation of the drive motor 1a (details will be described later) is executed. (See step S114 in FIG. 2).
On the other hand, when it is determined in step S106 that the predetermined time has not elapsed (in the case of NO), the process proceeds to step S108 described later.

Here, the fail-safe operation in the embodiment of the present invention will be described with reference to FIG.
FIG. 3 is an explanatory diagram for explaining the relationship between the duty of the speed control signal and the rotational speed of the driving motor 1a in the embodiment of the present invention. First, in the embodiment of the present invention, from the viewpoint of operational stability and the like, the range in which the duty of the speed control signal is a predetermined value d4 (%) or more and a predetermined value d5 (%) or less is normal. It is defined as an operation region (see FIG. 3). That is, when the duty of the speed control signal is in the above-described normal operation range, the drive motor 1a starts from the predetermined minimum rotational speed Va as the duty of the speed control signal is increased by the motor control unit 102 and the drive circuit 103. It is driven up to a predetermined maximum rotational speed Vmax (see FIG. 3). When the duty is d5 or more, the motor rotation speed is held at the maximum rotation speed Vmax.

On the other hand, the range where the duty of the speed control signal is not less than the predetermined value d2 (%) and not more than the predetermined value d3 (%) is set as the operation stop range (see FIG. 3).
When the duty of the speed control signal is between the predetermined values d3 (%) to d4 (%) (d4> d3), known and well-known hysteresis is set from the viewpoint of operational stability and the like. .

Moreover, the range where the duty of the speed control signal is equal to or less than the predetermined value d2 (%) and the range where the duty of the speed control signal is equal to or greater than the predetermined value d6 (%) (d6> d5) are outside the range of the duty setting of the speed control signal, Below the predetermined value d2 (%), the motor rotational speed is held at a predetermined rotational speed Vb (Va <Vb). For convenience of explanation, a range in which the duty of the speed control signal is equal to or less than the predetermined value d2 (%) is referred to as “outside the first range”, and a range in which the duty of the speed control signal is equal to or greater than the predetermined value d6 (%) It will be referred to as “out of the second range”.
In particular, in the embodiment of the present invention, as described above, the duty 0 (%) is a state in which the speed control signal in the motor control unit 102 is the logic value Low, that is, for example, the signal harness 2 is Shorted to ground due to the cause.
On the other hand, the duty 100 (%) is a state in which the speed control signal in the motor control unit 102 is a logical value High, that is, for example, a state in which the signal harness 2 is opened (opened) for some reason.

  In the portion where the duty of the speed control signal moves from the stop range to outside the first range, hysteresis is provided in the range of duty d2 (%) to d1 (%) from the viewpoint of operation stability or the like ( (See FIG. 3). On the other hand, a hysteresis is similarly provided in the portion where the duty moves outside the second range in the range of the duty from d6 (%) to d7 (%) (see FIG. 3).

  When it is determined that the signal harness 2 is in the open state (see step S100 in FIG. 2) and the process proceeds to step S114, the drive motor 1a is driven at the rotational speed Vb (FIG. 3). reference).

On the other hand, when it is determined that the signal harness 2 is in a short state (see step S104 in FIG. 2) and the process proceeds to step S114, the drive motor 1a is driven at a predetermined speed Va (FIG. 3). reference).
In the embodiment of the present invention, as will be described later, even when the duty of the speed control signal is other than 0 (%) or 100%, a region outside the predetermined range, that is, the duty is a predetermined value. Even in the range of d2 (%) or less and the predetermined value d6 (%) or more, the drive motor 1a is made failsafe by assuming that the duty of the speed control signal is 0 (%) or 100%. It is supposed to be driven.

  Returning to the description of FIG. 2 again, when it is determined in step S104 that the signal harness 2 is not in a short state (in the case of NO), the duty of the speed control signal is predetermined in step S108. It is determined whether it is outside the first range or outside the second range. In the example described with reference to FIG. 3, the outside of the first range is a range where the duty is d2 (%) or less, and the outside of the second range is a range where the duty is d6 (%) or more. . In other words, the area outside the first or second range is an area where the duty of the speed control signal is outside the range preset as the normal drive range of the drive motor 1a.

When it is determined in step S108 that the duty of the speed control signal is outside the first or second range (in the case of YES), the process proceeds to step S110 to determine whether or not a predetermined time has elapsed. If it is determined that the predetermined time has passed (in the case of YES), the fail safe operation of the cooling fan 1 is executed (see step S114 in FIG. 2). .
That is, in this case, when the speed control signal is outside the first range, the duty of the speed control signal is 0 (%), that is, in other words, the signal harness 2 is in a short state. If the speed control signal is out of the second range, the duty of the speed control signal is 100 (%), that is, the signal harness 2 is in an open state. As described above, the fail-safe operation corresponding to each case is applied as described above.

  That is, as described above, the fail safe operation in the embodiment of the present invention is an operation state in which the motor rotational speed is maintained at the predetermined rotational speed Vb when the duty of the speed control signal is d2 (%) or less. When the duty of the speed control signal is d6 (%) or more, there is an operation state in which the motor rotational speed is maintained at the predetermined rotational speed Vb (see FIG. 3). Therefore, in step S108, it is determined whether the duty of the speed control signal is out of the first or second range. In step S114, the above-described fail-safe operation is performed according to the determination result. Will be made.

  On the other hand, if it is determined in step S108 that the duty of the speed control signal is not outside the predetermined range (NO), the process proceeds to step S112, and the duty of the speed control signal stops the driving motor 1a. It is determined whether or not the state is within a predetermined range. Here, the case where the duty of the speed control signal is within a predetermined range in which the driving motor 1a is stopped is the case where the duty of the speed control signal is d2 to d3 in the example described in FIG. (%).

  In step S112, when it is determined that the duty of the speed control signal is within a predetermined range in which the drive motor 1a is stopped (in the case of YES), the process proceeds to step S116, where the cooling fan 1 is stopped, that is, The drive motor 1a is brought into a drive stop state.

On the other hand, when it is determined in step S112 that the duty of the speed control signal is not within the predetermined range in which the driving motor 1a is stopped (in the case of NO), the cooling fan 1 is operated normally (in FIG. 2). Step S118). That is, the driving motor 1a is driven by the driving circuit 103 at a motor rotation speed corresponding to the duty of the speed control signal based on the control signal from the motor control unit 102 ("operating range" in FIG. 3). (See the section labeled as).
Then, after any one of steps S114, S116, and S118 is executed, the process returns to the previous step S100 again, and a series of processes is repeated.

Next, a second embodiment will be described with reference to FIGS.
First, a configuration example of the battery protection device S in the second embodiment will be described with reference to FIG. The same components as those shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. Hereinafter, different points will be mainly described.
The battery protection device S according to the second embodiment has a function for notifying the main control unit 101 of this state, particularly when the fail-safe operation described above is performed. This is in addition to the configuration shown in FIG.
In the second embodiment, the drive motor 1a is preferably a brushless motor having sensors 5a to 5c for detecting the rotational position of a rotor (not shown).

  In the motor control unit 102 in the second embodiment, the output signals of the sensors 5a to 5c are detected, and the main control unit 101 corresponds to the output signals of the sensors 5a to 5c in an appropriate signal format. Rotation detecting means 201 is provided for outputting the detected signal. The rotation detection unit 201 has a function of outputting information of the detected output signals of the sensors 5a to 5c to the drive control unit 202 that outputs a control signal to the drive circuit 103 based on the speed control signal. Plays. As is well known, the output timing and switching timing of the drive signal are determined based on the output signals of the sensors 5a to 5c, in other words, based on the position of the rotor (not shown). It is because it has come to be.

In addition, the motor control unit 102 detects an abnormality in the speed control signal, and when an abnormality in the speed control signal is detected, the motor control unit 102 replaces the rotation signal for the main control unit 101 with the main control unit. An abnormality detecting means 203 is provided for outputting a predetermined signal (diagnostic signal) indicating that the speed control signal is abnormal to the unit 101 (details will be described later).
In the embodiment of the present invention, the rotation detection unit 201, the drive control unit 202, and the abnormality detection unit 203 are realized by executing a processing procedure program as described below in the motor control unit 102. Has become.

Next, a second processing procedure example of fan drive control in the battery overheat protection device executed by the motor control unit 102 in the configuration shown in FIG. 4 will be described with reference to FIG. The same steps as those shown in FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted. Hereinafter, different points will be mainly described.
When the process is started, it is determined that the speed control signal is not in the open state as described above, that is, not the logical value High (see step S100 in FIG. 5), and then the speed control signal is not in the short state. That is, it is determined that it is not the logical value Low (see step S104 in FIG. 5), and it is determined that the duty of the speed control signal is not within the predetermined stop range of the driving motor 1a (in the case of NO). Then (see step S112 in FIG. 5), the cooling fan 1, in other words, the drive motor 1a is operated normally (see step S118 in FIG. 5 and FIG. 3).
In such a normal operation state, a signal corresponding to the output signals of the sensors 5a to 5c is transmitted from the motor control unit 102 to the main control unit 101 as a rotation signal indicating the rotation state (operation state) of the drive motor 1a. Is output (see step S124 in FIG. 5).

In step S112, if it is determined that the duty of the speed control signal is within a predetermined stop range of the driving motor 1a (in the case of YES), the cooling fan 1, in other words, the driving motor 1a is The stop state is set (see step S116 in FIG. 5).
In such a rotation stop state, a rotation signal having a predetermined signal level (for example, logical value Low) indicating the drive stop state of the drive motor 1a is output to the main control unit 101 (step in FIG. 5). (See S122).

  On the other hand, it is determined that the speed control signal is a predetermined signal state corresponding to the open state (in the case of “YES” in step S100 in FIG. 5), or the speed control signal is a predetermined signal corresponding to the short state. If it is determined that the vehicle is in a state (in the case of “YES” in step S104 in FIG. 5), fail-safe operation is performed as described above (see step S114 in FIG. 5).

Next, a diagnosis signal corresponding to the abnormal state of the speed control signal is output as the rotation signal (see step S120 in FIG. 5).
That is, fail-safe operation is performed when the duty of the speed control signal is in an abnormal state other than the value that should originally be, as described above with reference to FIG. Specifically, in the example shown in FIG. 3, the speed control signal is in an abnormal state when the duty of the speed control signal is equal to or less than a predetermined value d2 and when the duty of the speed control signal is equal to or greater than the predetermined value d6. It corresponds to.

  In step S120, the rotation signal is switched from a signal corresponding to the output signal of the sensors 5a to 5c to a predetermined signal (diagnosis signal) indicating that the speed control signal is in an abnormal state. The data is output from the unit 102 to the main control unit 101. Here, as the predetermined signal representing the abnormal state of the speed control signal, for example, with respect to the range of the repetition frequency of the signals output from the sensors 5a to 5c when the drive motor 1a is in a normal rotation state, A pulse signal having a repetitive frequency sufficiently separated is suitable.

In particular, in the case of the embodiment of the present invention, the repetition frequency when the duty of the speed control signal is less than or equal to the predetermined value d2 is different from the repetition frequency when the duty of the speed control signal is less than or equal to the predetermined value d6. Then, it is preferable because the main control unit 101 can determine whether the signal harness 2 is in a short state or an open state.
As a specific repetition frequency of the diagnosis signal, for example, an extremely long repetition period that is not used in the normal operation range of the driving motor 1a is clearly distinguished from the normal driving state. It is preferable from the viewpoint of enabling the

FIG. 6 shows a procedure example of a subroutine process for notifying abnormality of the battery overheat protection device based on the rotation signal executed in the microcomputer 101a constituting the main control unit 101. Refer to FIG. However, the contents will be described.
The process shown in FIG. 6 takes one form of various subroutine processes executed in the microcomputer 101a of the main control unit 101.

  Hereinafter, more specifically, when the processing is started, it is determined whether or not the rotation signal is a diagnosis signal (see step S200 in FIG. 6). If it is determined that the rotation signal is a predetermined diagnosis signal as described above (in the case of YES), a notification process is performed (see step S202 in FIG. 6). Here, specific examples of the notification include the generation of an alarm sound, the lighting of a display lamp such as a warning lamp, and a predetermined character or graphic using a display element capable of displaying a character or graphic. It is preferable to use a publicly known or well-known method such as display.

  In particular, when the diagnosis signal differs according to the difference in the abnormal state of the speed control signal, that is, in other words, when the speed control signal is determined to be in the open state as described above (see step S100 in FIG. 2). ) And when the speed control signal is determined to be in a short state (see step S104 in FIG. 2), if the diagnosis signal is different, the notification may be different depending on the signal state, so that the driver This is preferable because it is possible to distinguish what abnormal state the user is in.

  In the second embodiment described above, the rotation detection means 201 is realized by executing steps S100, S104, S112, and S124 by the motor control unit 102, and by executing steps S100, S104, and S120 by the motor control unit 102. The abnormality detection unit 203 is realized, and the drive control unit 202 is realized by the execution of steps S114, S116, and S118 by the motor control unit 102.

It is a block diagram which shows the 1st structural example of the battery overheat protection apparatus in embodiment of this invention. 2 is a flowchart showing a procedure of fan drive control processing in a battery overheat protection device executed by a motor control unit in the configuration shown in FIG. 1. It is explanatory drawing explaining the relationship between the duty of the speed control signal in the drive control of the cooling fan by the battery overheat protection device of embodiment of this invention, and the rotational speed of the motor for driving a cooling fan. It is a block diagram which shows the 2nd structural example of the battery overheat protection apparatus in embodiment of this invention. 5 is a flowchart showing a procedure of fan drive control processing in the battery overheat protection device executed by the motor control unit in the configuration shown in FIG. 4. 5 is a subroutine flowchart showing a procedure of abnormality notification processing executed by a main control unit in the configuration shown in FIG. 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Cooling fan 2 ... Signal harness 3 ... Auxiliary battery 4 ... Connector 5a-5c ... Sensor 101 ... Main control part 102 ... Motor control part 103 ... Drive circuit

Claims (10)

A fan for cooling the battery, a speed control signal for setting the rotational speed of the fan is input from the outside, and the fan is driven and controlled to a rotational speed based on the speed control signal; and the speed control Speed control is performed by detecting whether the signal is in a first abnormal state equivalent to a short-circuit state of the transmission line or whether the speed control signal is in a second abnormal state equivalent to an open state of the transmission line. When it is detected that a signal is in the first abnormal state, the fan is driven at a predetermined rotational speed, and when a speed control signal is detected in the second abnormal state. Is a fan drive control method in a battery overheat protection device configured to drive the fan at a predetermined rotational speed,
The speed control signal has a proportional relationship between the index value and the rotation speed of the fan, and the fan operating range and the stop range are adjacent to the index value along the increasing direction of the index value in advance. one set et is Ru, adjacent to the stop range, and the operating range and will be the first range is set to the opposite side, adjacent to the operating range, and, the opposite side to the stop range 2 is set and the index value is detected to be out of the first range, it is assumed that the speed control signal is in the first abnormal state, while the index value is in the second range. If it is outside is detected, the speed control signal is fiction to be in the second abnormal state, characterized and to Luba Tteri overheat protection device that is driven in rotation speed corresponding to each state of the fan Fan drive control method. The speed control signal is a repetitive pulse signal with a variable repetition period and a variable duty cycle whose pulse width is changed according to a desired fan rotation speed, and the speed control signal is in a state where the duty is 0%. when determining that the a first abnormal state, also, the speed control signal, according to claim 1, characterized in that it is determined that the when the duty is 100% of the state is the second abnormal state Fan control method in the battery overheat protection device of the present invention. The speed control signal uses the duty as an index value, and when it is detected that the index value is equal to or less than a first predetermined value, the speed control signal presumes that the speed control signal is in the first abnormal state, while the index When it is detected that the value is equal to or greater than a second predetermined value, the speed control signal is assumed to be in a second abnormal state, and the fan is driven to a rotational speed corresponding to each state. A fan drive control method for a battery overheat protection device according to claim 2 . When it is detected that the speed control signal is in the first abnormal state or the second abnormal state, the fact that the driving state of the fan is in an abnormal state is notified to the outside. The fan drive control method in the battery overheat protection apparatus in any one of Claims 1 thru | or 3 . The notification is performed by outputting a repetitive pulse signal having a different repetitive frequency depending on whether the speed control signal is in a first abnormal state or a second abnormal state. 5. A fan drive control method in the battery overheat protection device according to 4 . A fan for cooling the battery is provided, a speed control signal for setting the rotational speed of the fan is input from the outside, and the fan is driven and controlled to a rotational speed based on the speed control signal. And a drive circuit that controls energization of a motor that drives the fan, and a motor control unit that outputs a control signal for controlling the operation of the drive circuit to the drive circuit based on the speed control signal. ,
The motor control unit is in a first abnormal state in which the speed control signal is equivalent to a short circuit state of the transmission line, or a second abnormal state in which the speed control signal is equivalent to an open state of the transmission line. When the speed control signal is detected to be in the first abnormal state, the operation of the drive circuit is controlled so that the fan is driven at a predetermined rotational speed. A battery overheat configured to control the operation of the drive circuit so that the fan is driven at a predetermined rotational speed even when the speed control signal is detected to be in the second abnormal state. A protective device,
Said speed control signal has a rotational speed proportional to the index value and the fan, while operating range and stop range of the fan to the index value Ru been found previously determined so as to be adjacent, adjacent to the operating range And the outside of the first range is set on the side opposite to the stop range, the outside of the second range is set on the side adjacent to the stop range and opposite to the operation range,
When the motor control unit detects that the index value is out of the first range, the motor control unit assumes that the speed control signal is in the first abnormal state, while the index value is out of the second range. Is detected, the speed control signal is assumed to be in the second abnormal state, and the operation of the drive circuit is controlled so that the fan is driven at a rotational speed corresponding to each state. features and to Luba Tteri overheating protection device that. The speed control signal is a repetitive pulse signal with a variable repetition period and a variable duty cycle whose pulse width is changed according to a desired fan rotation speed, and the speed control signal is in a state where the duty is 0%. when determining that the a first abnormal state, also, the speed control signal, according to claim 6, characterized in that it is determined that the when the duty is 100% of the state is the second abnormal state Battery overheat protection device. The speed control signal has its duty as an index value,
When the motor control unit detects that the index value is less than or equal to the first predetermined value, the motor control unit presumes that the speed control signal is in the first abnormal state, while the index value is greater than or equal to the second predetermined value. If detected, the speed control signal is assumed to be in the second abnormal state, and the operation of the drive circuit is controlled so that the fan is driven at a rotational speed corresponding to each state. The battery overheat protection device according to claim 7 . When the motor control unit detects that the speed control signal is in the first abnormal state or the second abnormal state, the motor control unit notifies the outside that the fan drive state is in the abnormal state. battery overheat protection device according to any one of claims 6 to 8, characterized by comprising configured. The notification is performed by outputting a repetitive pulse signal having a different repetitive frequency depending on whether the speed control signal is in a first abnormal state or a second abnormal state. The battery overheat protection device according to 9 .

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