vehicle

Abstract

A vehicle according to the present invention comprises: a vehicle battery; a motor generator that is capable of inputting and outputting electric power to and from the vehicle battery and an external battery which is externally provided; a circuit unit that connects the motor generator to the vehicle battery and the external battery; and a control unit that controls the vehicle battery and the external battery. When electric power is input to and output from both the vehicle battery and the external battery, the control unit restricts input and output of electric power to and from one of the vehicle battery and the external battery on the basis of a load applied to the circuit unit.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles.

Background Art

[0002] Conventionally, there has been proposed a vehicle that runs by a motor that receives power supply from a main battery mounted on a vehicle body and a sub-battery that can be attached to and detached from the vehicle body (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described vehicle, the power of the sub-battery is preferentially used, and the power of the main battery is used after the sub-battery becomes empty. Therefore, in the vehicle, no measures have been taken regarding the safety when both the main battery and the sub-battery are used simultaneously.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to maintain safety while improving power performance.

Means for Solving the Problems

[0006] A vehicle according to an embodiment of the present invention includes a vehicle battery, a motor generator capable of inputting and outputting power to the vehicle battery and an external battery provided outside, the vehicle battery and the external battery, and a circuit unit connecting the motor generator. Based on either the first mode or the second mode, a control unit that controls the vehicle battery and the external battery, The first mode is a mode in which power is transferred between the motor generator and the vehicle battery, and between the vehicle battery and the external battery, and no power is transferred between the motor generator and the external battery; the second mode is a mode in which power is transferred between the motor generator and the vehicle battery, and between the motor generator and the external battery; The control unit is In the second mode, if the load on the circuit exceeds a predetermined load, the system switches to the first mode. . [Effects of the Invention]

[0007] According to the present invention, it is possible to improve power performance while maintaining safety. [Brief explanation of the drawing]

[0008] [Figure 1] This diagram shows an overview of the vehicle system configuration. [Figure 2] This is a diagram illustrating the functional configuration of the control unit. [Figure 3] This diagram shows the power flow when driving a motor generator in normal mode. [Figure 4] This flowchart shows the control flow of the trailer battery in normal mode. [Figure 5] This diagram shows the power flow when driving the motor generator in boost mode. [Figure 6] This diagram explains the process during boost mode. [Figure 7] This diagram explains the process during boost mode. [Figure 8] This graph shows the smoke emission characteristics. [Modes for carrying out the invention]

[0009] <1. Vehicle System Configuration> Figure 1 is a diagram showing the configuration overview of vehicle system 1. As shown in Figure 1, vehicle system 1 comprises a vehicle 2 and a trailer 3. Vehicle 2 and trailer 3 are mechanically and electrically connected via a connecting part 4. Trailer 3 is also detachable from vehicle 2.

[0010] Vehicle 2 is an electric vehicle equipped with a motor generator 11, an inverter 12, a vehicle battery 13, and a control unit 14.

[0011] The motor generator 11 is a power source for driving the vehicle 2 and is, for example, a three-phase AC motor. The motor generator 11 generates a driving force by the electric power supplied from one or both of the vehicle battery 13 and the trailer battery 22 described later via the inverter 12, and drives the vehicle 2 by transmitting the driving force to the drive wheels.

[0012] Also, the motor generator 11 generates electric power by performing regenerative operation. The electric power generated by the regenerative operation of the motor generator 11 can be supplied to the vehicle battery 13 and the trailer battery 22 via the inverter 12.

[0013] The inverter 12 converts the DC current input from the vehicle battery 13 and the trailer battery 22 into a three-phase AC current and outputs it to the motor generator 11. Also, when the motor generator 11 performs regenerative operation, the inverter 12 converts the AC current input from the motor generator 11 into a DC current and outputs it to the vehicle battery 13 and the trailer battery 22.

[0014] The vehicle battery 13 is a so-called high-voltage secondary battery and is mounted, for example, under the floor. The vehicle battery 13 stores electricity for supplying to the motor generator 11. Also, the vehicle battery 13 can be charged by the regenerative operation of the motor generator 11. Note that the vehicle battery 13 may be charged by the electric power supplied from the trailer battery 22.

[0015] The control unit 14 is composed of a computer such as one or more ECUs (Electronic Control Unit) and controls the vehicle 2 and the trailer 3 as a whole. Details of the control unit 14 will be described later.

[0016] The trailer 3 has no power source and is towed by the vehicle 2. The trailer 3 includes a converter 21 and a trailer battery 22.

[0017] Converter 21 is a DC (Direct Current) / DC converter. Converter 21 converts the voltage of the direct current input from trailer battery 22 and outputs it to vehicle 2 (motor generator 11, vehicle battery 13). Also, converter 21 converts the voltage of the direct current input from vehicle 2 (motor generator 11) and outputs it to trailer battery 22.

[0018] Trailer battery 22 is a so-called high-voltage secondary battery. Trailer battery 22 stores electricity for supplying to motor generator 11 and vehicle battery 13. Also, trailer battery 22 can be charged by regenerative operation of motor generator 11.

[0019] In vehicle system 1 having such a configuration, compared to vehicle 2 alone, the power that can be supplied to motor generator 11 is increased by the amount that trailer battery 22 is connected, and it is possible to extend the cruising distance that can be traveled with one charge. On the other hand, in vehicle system 1, since vehicle 2 will tow trailer 3, the overall weight increases and the power performance deteriorates.

[0020] Therefore, in vehicle system 1, by simultaneously supplying both the power output from vehicle battery 13 and the power output from trailer battery 22 to motor generator 11, the driving force of motor generator 11 can be increased, and the power performance of vehicle system 1 can be improved.

[0021] Figure 2 is a diagram for explaining the functional configuration of control unit 14. As shown in Figure 2, control unit 14 functions as mode setting unit 31, state detection unit 32, and power supply control unit 33. The mode setting unit 31 sets the control mode for controlling the motor generator 11, vehicle battery 13, and trailer battery 22 to one of several control modes. In this embodiment, a normal mode and a boost mode are provided as control modes. However, the control modes are not limited to these and other modes may be provided. The state detection unit 32 detects the state of the vehicle battery 13 and the trailer battery 22. The detected states include SOC (State of Charge), temperature, input / output current values, voltage values, etc., and also include the input power (hereinafter referred to as input power) and output power (hereinafter referred to as output power) calculated from these values. The power control unit 33 controls the motor generator 11, the vehicle battery 13, and the trailer battery 22 based on the control mode set by the mode setting unit 31 and the status of the motor generator 11 and the trailer battery 22 detected by the status detection unit 32.

[0022] <2. Normal Mode> Figure 3 shows the power flow when driving the motor generator 11 in normal mode. In Figure 3, the power flow is indicated by arrows.

[0023] In normal mode, power is transferred between the motor generator 11 and the vehicle battery 13, as well as between the vehicle battery 13 and the trailer battery 22. However, in normal mode, power is not transferred between the motor generator 11 and the trailer battery 22.

[0024] As shown in Figure 3, when the motor generator 11 is driven, power is supplied from the vehicle battery 13 to the motor generator 11 via the inverter 12. If the state of charge (SOC) of the vehicle battery 13 is low, power is supplied from the trailer battery 22 to the vehicle battery 13 via the converter 21, and the vehicle battery 13 is charged.

[0025] Therefore, since the motor generator 11 generates driving force using power supplied from the vehicle battery 13, the driving force it can generate is smaller than that of the boost mode described later.

[0026] Furthermore, when the motor generator 11 performs regenerative operation, the power generated by the motor generator 11 is supplied to the vehicle battery 13 via the inverter 12, but not to the trailer battery 22.

[0027] Figure 4 is a flowchart showing the control flow of the trailer battery 22 in normal mode. The processes shown in Figure 4 are performed when the state detection unit 32 has set the system to normal mode. When the process for controlling the trailer battery 22 is started, in step S1 the state detection unit 32 detects the state of the vehicle battery 13. Here, the state of charge (SOC) and input power of the vehicle battery 13 are detected. Next, in step S2, the power control unit 33 obtains the upper limit threshold for the SOC, which has been set in advance by the user. The upper limit threshold indicates the upper limit of the SOC desired by the user.

[0028] In step S3, the power control unit 33 determines whether the State of Charge (SOC) of the vehicle battery 13 is below the upper threshold. If the SOC of the vehicle battery 13 is not below the upper threshold (No in step S3), the process shown in Figure 4 is terminated. On the other hand, if the State of Charge (SOC) of the vehicle battery 13 is below the upper threshold (Yes in step S3), the state detection unit 32 detects the state of the trailer battery 22 in step S4. Here, the SOC and output power of the trailer battery 22 are detected.

[0029] Next, in step S5, the state detection unit 32 calculates the power output from the vehicle battery 13, that is, the power consumption of the vehicle battery 13. Also, in step S6, the power control unit 33 calculates the power that can be supplied from the trailer battery 22 to the vehicle battery 13 (supplied power) based on the input power and power consumption of the vehicle battery 13 and the output power of the trailer battery 22. Then, in step S7, the power control unit 33 controls the supply power calculated in step S6 to be supplied from the trailer battery 22 to the vehicle battery 13.

[0030] <3. Boost Mode> Figure 5 shows the power flow when driving the motor generator 11 in boost mode. In Figure 5, the power flow is indicated by arrows.

[0031] In boost mode, power is transferred between the motor generator 11 and the vehicle battery 13, and also between the motor generator 11 and the trailer battery 22. At this time, power can be supplied to the motor generator 11 from both the vehicle battery 13 and the trailer battery 22 simultaneously, and power can be supplied from the motor generator 11 to both the vehicle battery 13 and the trailer battery 22 simultaneously.

[0032] Therefore, a large current may flow through the circuit section 15 (harness) located between both the vehicle battery 13 and the trailer battery 22 and the motor generator 11. When a large current flows through the circuit section 15, it may overheat and cause a fire or smoke. Therefore, the vehicle system 1 takes the following measures to prevent a fire or smoke from occurring in the circuit section 15. Note that the circuit section 15 may include electronic components in addition to the harness.

[0033] Figures 6 and 7 illustrate the processing in boost mode. When the mode setting unit 31 sets the system to boost mode, the control unit 14 performs the processing shown in Figures 6 and 7. In step S11, the state detection unit 32 detects the state of the vehicle battery 13. Here, the state detection unit 32 detects the state of charge (SOC), input power, and output power of the vehicle battery 13.

[0034] Next, in step S12, the state detection unit 32 detects the state of the trailer battery 22. Here, the state detection unit 32 detects the state of charge (SOC), input power, and output power of the trailer battery 22.

[0035] In step S13, the power control unit 33 calculates the total input power (hereinafter referred to as total input power) by adding the input power of the vehicle battery 13 detected in step S11 and the input power of the trailer battery 22 detected in step S12. Furthermore, in step S14, the power control unit 33 calculates the total output power (hereinafter referred to as total output power) by adding the output power of the vehicle battery 13 detected in step S11 and the output power of the trailer battery 22 detected in step S12.

[0036] In step S15, the power control unit 33 determines whether there has been any operation on the accelerator pedal. If there has been no operation on the accelerator pedal (No in step S15), the process moves to step S20. On the other hand, if there is an operation on the accelerator pedal (Yes in step S15), in step S16 the power control unit 33 sets a target acceleration based on the amount of operation on the accelerator pedal (depression amount) and the speed of the vehicle 2 (vehicle speed). The power control unit 33 then calculates the driving force of the motor generator 11 so that the set target acceleration can be achieved. The power control unit 33 also calculates the power (driving power) required to output the calculated driving force from the motor generator 11. If the driving power calculated here exceeds the total output power, the driving power is limited to the total output power.

[0037] In the following step S17, the power control unit 33 determines whether the output power of the vehicle battery 13 is equal to or greater than the driving power. If the output power of the vehicle battery 13 is equal to or greater than the driving power (Yes in step S17), the driving power required to output the calculated driving force to the motor generator 11 can be supplied by the vehicle battery 13 alone. Therefore, in step S18, the power control unit 33 controls the output of drive power from the vehicle battery 13 to the motor generator 11 and stops the output of power from the trailer battery 22. In other words, the power control unit 33 prioritizes using the vehicle battery 13 to drive the motor generator 11.

[0038] On the other hand, if the power output of the vehicle battery 13 is not greater than or equal to the driving power (No in step S17), the vehicle battery 13 alone will not be able to provide the driving power necessary to output the calculated driving force to the motor generator 11. Therefore, in step S19, the power control unit 33 controls the vehicle battery 13 to output the available power, and also controls the trailer battery 22 to output the power obtained by subtracting the available power of the vehicle battery 13 from the drive power (the deficit). This allows the vehicle system 1 to drive the motor generator 11 using power from both the vehicle battery 13 and the trailer battery 22 simultaneously. In other words, the vehicle system 1 can improve its driving performance.

[0039] As shown in Figure 7, in step S20, the power control unit 33 determines whether there has been any operation on the brake pedal. If there has been no operation on the brake pedal (No in step S20), the process moves to step S25. On the other hand, if the brake pedal is operated (Yes in step S20), in step S21 the power control unit 33 sets a target deceleration based on the amount of brake pedal operation (pressure) and the speed of the vehicle 2 (vehicle speed). The power control unit 33 then calculates the braking force of the motor generator 11 so that the set target deceleration can be achieved. The power control unit 33 also calculates the power that can be regenerated by the motor generator 11 (regenerative power) based on the calculated braking force. If the regenerative power calculated here exceeds the total input power, the regenerative power is limited to the total input power.

[0040] In the following step S22, the power control unit 33 determines whether the input power available to the vehicle battery 13 is greater than or equal to the regenerative power. If the input power available to the vehicle battery 13 is greater than or equal to the regenerative power (Yes in step S22), then all of the power regenerated by the motor generator 11 can be used to charge the vehicle battery 13. Therefore, in step S23, the power control unit 33 controls the system to input all the power regenerated by the motor generator 11 to the vehicle battery 13 and to stop the input of power to the trailer battery 22. In other words, the power control unit 33 prioritizes charging the vehicle battery 13.

[0041] On the other hand, if the input power of the vehicle battery 13 is not greater than or equal to the regenerative power (No in step S22), then not all of the power regenerated by the motor generator 11 can be used to charge the vehicle battery 13. Therefore, in step S24, the power control unit 33 controls the regenerated power from the motor generator 11 to be input to the vehicle battery 13 as it is available for input, and the power obtained by subtracting the available input power of the vehicle battery 13 from the regenerated power (the excess) is input to the trailer battery 22. This allows the vehicle system 1 to charge the vehicle battery 13 and the trailer battery 22 simultaneously.

[0042] In step S25, the power control unit 33 detects the current values ​​and energizing time of the currents input and output to the vehicle battery 13 and the trailer battery 22. Here, the current value and energizing time of the current passing through the circuit unit 15 are detected by summing the current values ​​input and output to the vehicle battery 13 and the trailer battery 22.

[0043] In step S26, the power control unit 33 performs a fire and smoke determination by referring to the smoke emission characteristics of the circuit unit 15 and determining whether there is a risk of fire or smoke emission in the circuit unit 15.

[0044] Figure 8 is a graph showing the smoke generation characteristics. In Figure 8, the vertical axis represents the smoke generation start time (s), and the horizontal axis represents the current (A). As shown in Figure 8, the smoke emission characteristics specify the smoke emission start time for each ambient temperature relative to the current applied. The smoke emission characteristics indicate that a larger current increases the likelihood of smoke emission in a shorter time. Furthermore, it indicates that a higher ambient temperature also increases the likelihood of smoke emission in a shorter time.

[0045] In vehicle 2, a smoke emission characteristics map showing the smoke emission characteristics of the circuit section 15 is pre-stored in the memory unit. The power control unit 33 uses the detection results from step S25 to calculate, for example, the current value, the average value of the current value over the past 1 second, the average value of the current value over the past 10 seconds, and the average value of the current value over the past 100 seconds. Then, the power control unit 33 makes a fire and smoke determination by referring to the smoke emission characteristics map based on the calculated current values ​​for different periods or their average value.

[0046] In step S27, the power control unit 33 determines whether there is a possibility of fire or smoke in the circuit unit 15. If there is no possibility of fire or smoke in the circuit unit 15 (No in step S27), the process is terminated.

[0047] On the other hand, if there is a possibility of fire or smoke in the circuit section 15 (Yes in step S27), in step S28 the mode setting section 31 terminates the boost mode and sets it to normal mode, and the process ends. As a result, in the vehicle system 1, the state in which power is simultaneously input and output to the motor generator 11 from both the vehicle battery 13 and the trailer battery 22 is discontinued, and power is input and output to the motor generator 11 only from the vehicle battery 13. Therefore, in the vehicle system 1, the possibility of a large current flowing through the circuit section 15 and causing ignition or smoke can be reduced, thereby maintaining or improving safety.

[0048] In the above-described embodiment, the current value, the average current value over the past 1 second, the average current value over the past 10 seconds, and the average current value over the past 100 seconds are calculated in the ignition and smoke detection. However, these periods are just examples, and it is possible to calculate the average current value over several different predetermined periods going back from the present.

[0049] <4. Variation> Although embodiments of the present invention have been described above, the present invention is not limited to the above-described examples and can take on a variety of configurations. For example, in the above embodiment, the possibility of fire or smoke emission of the circuit unit 15 is determined by referring to the smoke emission characteristics based on the current value (load) of the current flowing through the circuit unit 15 and the energizing time. However, this is not limited to the above, as long as the power control unit 33 can determine the possibility of fire or smoke emission of the circuit unit 15 based on the load of the circuit unit 15. For example, the power control unit 33 may determine the possibility of fire or smoke emission by directly measuring the temperature (load) of the circuit unit 15. Alternatively, the power control unit 33 may calculate the amount of heat generated by the circuit unit 15 (load) based on the current value and resistance value of the current flowing through the circuit unit 15, and determine the possibility of fire or smoke emission based on the calculated amount of heat generated.

[0050] Furthermore, in the embodiment described above, when there is a risk of smoke generation in the circuit section 15 during boost mode, the input and output of power to the trailer battery 22 is restricted. However, it is sufficient to restrict the input and output of power to either the vehicle battery 13 or the trailer battery 22.

[0051] <5. Summary of Embodiments> As described above, the vehicle 2 of the embodiment includes a vehicle battery 13, a motor generator 11 capable of inputting and outputting power to the vehicle battery 13 and an externally provided battery (trailer battery 22), a circuit unit 15 connecting the vehicle battery 13, the external battery, and the motor generator 11, and a control unit 14 that controls the vehicle battery 13 and the external battery. When there is power input and output to both the vehicle battery 13 and the external battery, the control unit 14 limits the power input and output to one of the vehicle battery 13 or the external battery based on the load on the circuit unit 15. As a result, vehicle 2 can drive the motor generator 11 with power output simultaneously from both the vehicle battery 13 and the trailer battery 22, thereby improving driving performance. Furthermore, even if the circuit unit 15 is subjected to a high load, vehicle 2 can reduce the risk of the circuit unit 15 catching fire or emitting smoke by limiting the power input and output to either the vehicle battery 13 or the trailer battery 22. Thus, vehicle 2 can maintain safety while improving its power performance.

[0052] The control unit 14 stops the output from the external battery (trailer battery 22) if the power that can be output from the vehicle battery 13 (outputtable power) is greater than or equal to the power used by the motor generator 11 (driving power). This allows vehicle 2 to prioritize the use of the vehicle battery 13.

[0053] The control unit 14 stops supplying power to the external battery (trailer battery 22) if the power that can be input to the vehicle battery 13 (inputable power) is greater than or equal to the regenerative power of the motor generator 11. This allows the vehicle battery 13 to be charged preferentially.

[0054] The control unit 14, based on the current value of the high-voltage circuit and the energizing time of the high-voltage circuit, refers to a smoke emission characteristics map to determine whether to limit the input and output of power to either the vehicle battery 13 or the external battery (trailer battery 22). This makes it possible to limit the power input and output to either the vehicle battery 13 or the trailer battery 22 before the circuit unit 15 ignites or emits smoke, thereby maintaining safety.

[0055] The control unit 14 limits the power input and output to the external battery by referring to a smoke characteristic map based on the current value and the average value of current values ​​over several predetermined periods prior to the present. This allows for accurate detection of the possibility of smoke emission from the circuit section 15, even if the current value passing through the circuit section 15 changes. [Explanation of symbols]

[0056] 1. Vehicle System 2 vehicles 3 Trailers 11 Motor Generator 13. Vehicle Battery 14 Control Unit 22 Trailer Battery 31 Mode setting section 32 State detection unit 33 Power Control Unit

Claims

1. Vehicle battery and A motor generator capable of inputting and outputting power to the vehicle battery and an externally provided battery, A circuit section connecting the vehicle battery and the external battery and the motor generator, A control unit that controls the vehicle battery and the external battery based on either the first mode or the second mode, Equipped with, The first mode is a mode in which power is transferred between the motor generator and the vehicle battery, power is transferred between the vehicle battery and the external battery, and power is not transferred between the motor generator and the external battery. The second mode is a mode in which power is transferred between the motor generator and the vehicle battery, and also between the motor generator and the external battery. The control unit switches to the first mode if the load on the circuit exceeds a predetermined load in the second mode. vehicle.

2. The transfer of power between the vehicle battery and the external battery in the first mode is charging from the external battery to the vehicle battery. The vehicle according to claim 1.

3. The control unit, If the power that can be output from the vehicle battery is greater than or equal to the power used by the motor generator, the output from the external battery is stopped. The vehicle according to claim 1.

4. The control unit, If the power that can be input to the vehicle battery is greater than or equal to the regenerative power of the motor generator, the power supply to the external battery is stopped. The vehicle according to claim 1.

5. The control unit, Based on the current value of the circuit and the energizing time of the circuit, a smoke emission characteristics map is referenced to determine whether to limit the power input / output to either the vehicle battery or the external battery. A vehicle according to any one of claims 1 to 4.

6. The control unit, Based on the current value and the average of current values ​​over several predetermined periods preceding the present, a smoke characteristic map is referenced to determine whether to limit the power input / output to either the vehicle battery or the external battery. The vehicle according to claim 5.

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