Vehicle battery charging control device

Abstract

To provide a vehicle battery charging control device capable of starting an engine even when a vehicle is in operation for a short time.SOLUTION: A battery charge control device for a vehicle 1 is provided with an engine 2, a motor generator 3, and a battery 4, and includes a control unit 20 that executes long-term unused battery charge control that sets the power generation voltage of the motor generator 3 on the basis of the unused time and the operating time of the vehicle 1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle battery charge control device. [Background technology]

[0002] Conventionally, Patent Document 1 proposes a technique for setting a target state of charge of a power storage device based on a planned unused period set by a user, and adjusting the state of charge of the power storage device to the target state. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-141209 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional technology described above does not take into account the vehicle's operating time, and therefore has the problem that if the vehicle's operating time is short, the battery will not be sufficiently charged and the engine will not be able to start.

[0005] The present invention has been made to solve the above-mentioned problems, and aims to provide a battery charging control device for a vehicle that can start the engine even if the vehicle has been in operation for a short time. [Means for solving the problem]

[0006] The battery charging control device for a vehicle of the present invention is a battery charging control device for a vehicle that is provided with an engine, a generator that generates electricity using the driving force of the engine, a battery that stores the electricity generated by the generator, and an engine starting device that starts the engine using electricity supplied from the battery, and is configured to include a control unit that executes long-term unused battery charging control that sets the power generation voltage of the generator based on the amount of time the vehicle has been left unused and the amount of time the vehicle has been in operation. [Effects of the Invention]

[0007] The present invention can provide a battery charge control device for a vehicle that can start the engine even if the vehicle has been in operation for a short time. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a vehicle equipped with a vehicle battery charge control device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a conceptual diagram showing a first map referenced by a vehicle battery charge control device according to an embodiment of the present invention. [Figure 3] FIG. 3 is a conceptual diagram showing a second map referenced by a vehicle battery charge control device according to an embodiment of the present invention. [Figure 4] FIG. 4 is a flowchart showing the battery charge control operation of the vehicle battery charge control device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] A vehicle battery charge control device according to one embodiment of the present invention is a vehicle battery charge control device provided with an engine, a generator that generates electricity using the driving force of the engine, a battery that stores the electricity generated by the generator, and an engine starting device that starts the engine using electricity supplied from the battery, and is characterized by including a control unit that executes long-term unused battery charge control that sets the generated voltage of the generator based on the amount of time the vehicle has been left unused and the amount of time the vehicle has been operating. As a result, the vehicle battery charge control device according to the embodiment of the present invention can start the engine even if the vehicle has been operating for a short period of time. [Example]

[0010] A vehicle equipped with a vehicle battery charge control device according to an embodiment of the present invention will be described below with reference to the drawings.

[0011] As shown in FIG. 1, a vehicle 1 includes an engine 2, a motor generator 3, a battery 4, an electric load 5, and an ECU (Electronic Control Unit) 6.

[0012] The engine 2 has a plurality of cylinders. In this embodiment, the engine 2 generates power to drive the vehicle 1 by performing a series of four strokes for each cylinder, which are an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke.

[0013] The motor generator 3 is provided so as to be interlocked with the crankshaft of the engine 2. In this embodiment, the motor generator 3 is configured by an ISG (Integrated Starter Generator).

[0014] The motor generator 3 functions as an engine starting device that starts the engine 2 by rotating when power is supplied from the battery 4. The motor generator 3 also functions as a generator that converts the power generated by the engine 2 into electric power.

[0015] The battery 4 is configured by a rechargeable secondary battery. The battery 4 stores the electric power generated by the motor generator 3 and supplies the electric power to drive the motor generator 3 and the electric load 5.

[0016] The ECU 6 is composed of a computer unit equipped with a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), flash memory for storing backup data, input ports, and output ports.

[0017] The ROM of this computer unit stores various constants, various maps, and the like, as well as a program for causing the computer unit to function as the ECU 6. That is, the CPU executes the program stored in the ROM using the RAM as a work area, causing the computer unit to function as the ECU 6 in this embodiment.

[0018] An input port of the ECU 6 is connected to various sensors including an ignition switch (hereinafter also simply referred to as “IG”) 10 and a battery sensor 11 that detects the charge / discharge current and terminal voltage of the battery 4.

[0019] Various control objects including the motor generator 3 are connected to the output port of the ECU 6. The ECU 6 controls the various control objects connected to the output port based on information obtained from various sensors connected to the input port.

[0020] The ECU 6 functions as a control unit 20 that executes long-term unused battery charge control that sets the power generation voltage of the motor generator 3 based on the unused time Tr of the vehicle 1 and the operating time Tw of the vehicle 1. In this embodiment, the unused time Tr of the vehicle 1 corresponds to the time the IG 10 was turned off, and the operating time Tw of the vehicle 1 corresponds to the time the IG 10 was turned on.

[0021] The ECU 6 stores historical information representing the state of the IG 10 in a flash memory. The ECU 6 calculates the abandoned time Tr of the vehicle 1 and the operating time Tw of the vehicle 1 based on the historical information stored in the flash memory. Therefore, the abandoned time Tr of the vehicle 1 corresponds to historical information on the abandoned time of the vehicle 1, and the operating time Tw of the vehicle 1 corresponds to historical information on the operating time of the vehicle 1.

[0022] For example, ECU 6 calculates the abandoned time Tr of vehicle 1 and the operating time Tw of vehicle 1 based on historical information (hereinafter simply referred to as "valid historical information") for the most recent predetermined period (e.g., the past year) stored in flash memory.

[0023] The ECU 6 calculates the average value of the time from when the IG 10 is turned off to when it is turned on from the valid history information, thereby calculating the idle time Tr of the vehicle 1. The ECU 6 also calculates the average value of the time from when the IG 10 is turned on to when it is turned off from the valid history information, thereby calculating the operating time Tw of the vehicle 1.

[0024] A first map as shown in Fig. 2 is stored in advance in the ROM of the ECU 6. In the first map, the generated voltage V1 is associated with an increase in the idle time Tr of the vehicle 1. The ECU 6 refers to the first map and calculates the generated voltage V1 from the idle time Tr.

[0025] A second map as shown in Fig. 3 is stored in advance in the ROM of the ECU 6. In the second map, the generated voltage V2 is associated with the vehicle 1 so that it increases as the operating time Tw of the vehicle 1 decreases. The ECU 6 refers to the second map and calculates the generated voltage V2 from the operating time Tw.

[0026] The ECU 6, which executes the long-term unused battery charging control, sets the generated voltage of the motor generator 3 to the higher of the generated voltage Vh, which is the generated voltage V1 calculated by referring to the first map, and the generated voltage V2 calculated by referring to the second map.

[0027] That is, the ECU 6 that executes the long-term unused battery charging control sets the generated voltage of the motor generator 3 to the higher of the generated voltage Vh, which is the generated voltage V1 based on the unused time Tr of the vehicle 1 and the generated voltage V2 based on the operating time Tw of the vehicle 1.

[0028] The ECU 6 executes long-term unused battery charging control when the unused time Tr of the vehicle 1 is longer than a predetermined time TH (for example, one week), and executes normal battery charging control when the unused time Tr of the vehicle 1 is equal to or shorter than the predetermined time TH.

[0029] The ECU 6 that executes the normal battery charge control sets the power generation voltage of the motor generator 3 according to the state of charge of the battery 4 calculated from the detection result of the battery sensor 11. For example, the ECU 6 that executes the normal battery charge control sets the power generation voltage of the motor generator 3 higher as the state of charge of the battery 4 becomes lower.

[0030] The battery charge control operation by the ECU 6 configured as above will be described with reference to Fig. 4. The battery charge control operation described below is repeatedly executed at predetermined time intervals (for example, every 10 ms) while the charging conditions for the battery 4 are met.

[0031] First, in S1, the ECU 6 determines whether the abandoned time Tr of the vehicle 1 is longer than the predetermined time TH. If it is determined in S1 that the abandoned time Tr of the vehicle 1 is longer than the predetermined time TH, the ECU 6 executes the process of S2. If it is determined in S1 that the abandoned time Tr of the vehicle 1 is not longer than the predetermined time TH, the ECU 6 executes the process of S3.

[0032] In S2, the ECU 6 executes long-term unused battery charging control. After executing the process of S2, the ECU 6 ends the battery charging control operation. In S3, the ECU 6 executes normal battery charging control. After executing the process of S3, the ECU 6 ends the battery charging control operation.

[0033] As described above, the vehicle battery charge control device of this embodiment executes long-term unused battery charge control to set the power generation voltage of the motor generator 3 based on the unused time Tr of the vehicle 1 and the operating time Tw of the vehicle 1, so that the engine 2 can be started even if the operating time of the vehicle is short.

[0034] In addition, the vehicle battery charge control device of this embodiment executes long-term unused battery charge control, and sets the power generation voltage of the motor-generator 3 so that it increases the longer the unused time Tr of the vehicle 1 is, and increases the shorter the operating time Tw of the vehicle 1, so that the engine 2 can be started even if the operating time of the vehicle is short.

[0035] In addition, the vehicle battery charge control device according to this embodiment executes long-term unused battery charge control when the unused time Tr of the vehicle 1 is longer than the predetermined time TH, thereby preventing unnecessary execution of long-term unused battery charge control.

[0036] Furthermore, by executing long-term unused battery charging control, the vehicle battery charging control device according to this embodiment sets the generated voltage of the motor-generator 3 to the higher of the generated voltage V1 based on the unused time Tr of the vehicle 1 and the generated voltage V2 based on the operating time Tw of the vehicle 1, thereby simplifying the setting of the generated voltage of the motor-generator 3.

[0037] In this embodiment, an example has been described in which the ECU 6 calculates the left-standing time Tr of the vehicle 1 and the operating time Tw of the vehicle 1 based on history information for the most recent predetermined period stored in the flash memory.

[0038] In contrast to this, the ECU 6 may calculate the abandoned time Tr of the vehicle 1 and the operating time Tw of the vehicle 1 based on a predetermined number (for example, 700) of recent pieces of history information stored in the flash memory.

[0039] In this embodiment, an example has been described in which the idle time Tr of the vehicle 1 corresponds to the time the IG 10 was turned off, and the operating time Tw of the vehicle 1 corresponds to the time the IG 10 was turned on.

[0040] In contrast to this, the idle time Tr of the vehicle 1 may correspond to the time the engine 2 was operating, and the operating time Tw of the vehicle 1 may correspond to the time the engine 2 was not operating. By configuring in this manner, the vehicle battery charge control device according to this embodiment may also be applied to a hybrid vehicle in which the vehicle 1 can be driven by a drive source other than the engine 2.

[0041] In addition, in this embodiment, an example has been described in which the ECU 6 that executes the long-term unused battery charging control refers to the first map shown in FIG. 2 to calculate the generated voltage V1 from the unused time Tr of the vehicle 1, refers to the second map shown in FIG. 3 to calculate the generated voltage V2 from the operating time Tw of the vehicle 1, and sets the generated voltage of the motor generator 3 to the higher of the generated voltage V1 and the generated voltage V2.

[0042] In contrast to this, instead of the first map and the second map, a third map in which the generation voltage of the motor-generator 3 is correlated with the idle time Tr of the vehicle 1 and the operating time Tw of the vehicle 1 may be stored in the ROM of the ECU 6, and the ECU 6 that executes the long-term idle battery charging control may set the generation voltage of the motor-generator 3 by referring to the third map.

[0043] In the third map, the generated voltage of the motor-generator 3 is associated with the vehicle 1 so that it increases as the idle time Tr of the vehicle 1 increases, and the generated voltage of the motor-generator 3 is associated with the vehicle 1 so that it increases as the operating time Tw of the vehicle 1 decreases.

[0044] In the present embodiment, as described with reference to FIG. 4, the ECU 6 repeatedly executes the battery charge control operation at predetermined time intervals over a period in which the charging conditions for the battery 4 are met.

[0045] In contrast, the power generation voltage of the motor generator 3 set by executing the long-term unused battery charge control will not change until the IG10 is turned off. Therefore, when the ECU 6 executes the long-term unused battery charge control, the ECU 6 may prohibit the execution of the battery charge control operation until the IG10 is turned off.

[0046] In addition, the ECU 6 that executes the long-term unused battery charging control may set a target state of charge of the battery 4 based on the unused time Tr of the vehicle 1, and set the power generation voltage of the motor generator 3 so that the state of charge of the battery 4 reaches the target state of charge within the operating time Tw of the vehicle 1.

[0047] In addition, in this embodiment, an example has been described in which the ECU 6 executes the long-term unused battery charging control when the unused time Tr of the vehicle 1 is longer than the predetermined time TH, but the ECU 6 may also execute the long-term unused battery charging control when, for example, a predetermined switch provided on the instrument panel of the vehicle 1 is operated.

[0048] While the present invention has been described with reference to an embodiment thereof, it will be apparent that modifications may be made thereto without departing from the scope of the present invention, and the present invention is disclosed with the understanding that equivalents of such modifications are intended to be encompassed within the scope of the appended claims. [Explanation of symbols]

[0049] 1 vehicle 2 engines 3. Motor generator (generator, engine starter) 4 Battery 20 Control Unit

Claims

1. The engine and a generator that generates electricity using the driving force of the engine; a battery that stores the power generated by the generator; an engine starting device that starts the engine by receiving power from the battery, A vehicle battery charge control device comprising: a control unit that executes long-term unused battery charge control that sets the power generation voltage of the generator based on the unused time of the vehicle and the operating time of the vehicle.

2. The control unit 2. The vehicle battery charging control device according to claim 1, wherein, by executing the long-term unused battery charging control, the generator power generation voltage is set to be higher the longer the unused time of the vehicle is, and the generator power generation voltage is set to be higher the shorter the operating time of the vehicle is.

3. The control unit 3. The vehicle battery charge control device according to claim 1, wherein the long-term unused battery charge control is executed when the unused time of the vehicle is longer than a predetermined time, and the normal battery charge control is executed when the unused time of the vehicle is equal to or shorter than the predetermined time, and the power generation voltage of the generator is set in accordance with the state of charge of the battery.

4. The control unit 3. The vehicle battery charge control device according to claim 1, wherein the power generation voltage of the generator is set to the higher of a power generation voltage based on the vehicle's unused time and a power generation voltage based on the vehicle's operating time by executing the long-term unused battery charge control.

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