Power supply unit

Abstract

The power supply unit houses the main DC / DC converter and the AC charger (charging circuit, sub-DC / DC converter) within a housing. The main DC / DC converter and the sub-DC / DC converter are arranged on the same layer of the housing. The charging circuit is arranged on a different layer than the main DC / DC converter and the sub-DC / DC converter. The main DC / DC converter and the sub-DC / DC converter, arranged on the same layer of the housing, are controlled to operate in a mutually exclusive manner.

Description

Technical Field

[0001] This disclosure relates to power supply units. Background Technology

[0002] Japanese Patent Publication No. 2014-230417 discloses a power converter that houses electronic components within a housing. Within the housing, a base having multiple through-holes for the flow of refrigerant to cool the electronic components is arranged. The electronic components are arranged on different surfaces of the base within the power converter, thereby increasing the area available for effectively cooling the electronic components. Summary of the Invention

[0003] To achieve a more spacious interior, electric vehicles, such as battery electric vehicles and plug-in hybrid electric vehicles, are expected to include smaller onboard units to save space.

[0004] Power converters, such as AC chargers that convert AC power supplied from an external AC (Alternating Current) power source into DC (Direct Current) power for charging the driving battery, main DC / DC converters that convert DC power from the driving battery into drive voltage for auxiliary devices, and sub-DC / DC converters that convert AC power supplied from an AC power source into drive voltage for auxiliary devices, can be mounted on electric vehicles. In one conceivable example, the functions of multiple on-board units including these power converters are integrated into a single unit to save more space compared to arranging multiple on-board units separately.

[0005] However, when integrating functions into a unit, multiple on-board devices are housed in the same housing, and thus, issues related to the heat generated in each on-board device can become significant. Specifically, when power converters that may generate a large amount of heat are arranged adjacent to each other, the risk of failure may increase due to thermal interference between the power converters.

[0006] This disclosure is made to solve the above-mentioned problems. The purpose of this disclosure is to reduce the size of power conversion units that integrate power conversion functions while reducing thermal interference between power converters.

[0007] (1) The power conversion unit according to this disclosure includes a first power converter, a second power converter, a controller for controlling the first and second power converters, and a housing having a plurality of receiving spaces defined by partition walls and housing the first power converter, the second power converter, and the controller. The first and second power converters are arranged in the same receiving space of the housing. The controller causes the first and second power converters to operate in a mutually exclusive manner.

[0008] Using the above configuration, the first and second power converters, arranged in the same housing space, operate in a mutually exclusive manner. In other words, when one of the first and second power converters is running, the other is stopped. As a result, the amount of heat generated by the first and second power converters can be reduced significantly compared to when both are running. Therefore, thermal interference between the power converters can be reduced while simultaneously decreasing size through unitization.

[0009] (2) In one embodiment, the partition wall has a refrigerant passage through which refrigerant flows.

[0010] Using the above configuration, the refrigerant passage of the partition wall reduces the heat generation of the first and second power converters.

[0011] (3) In one embodiment, the power supply unit is mounted on a vehicle configured to perform AC charging of a main battery mounted on the vehicle using AC power supplied from an external AC power source. A first power converter converts the power from the main battery into power to be supplied to auxiliary devices mounted on the vehicle. A second power converter converts the power supplied from the AC power source into power to be supplied to the auxiliary devices.

[0012] Considering ease of installation on a vehicle, it is desirable to minimize the increase in height of the power supply unit. The first and second power converters can supply power to the auxiliary device by operating at least one of them, and therefore can operate in a mutually exclusive manner. By arranging the first and second power converters, which can operate in a mutually exclusive manner, in the same housing space, the increase in height of the power supply unit can be minimized.

[0013] (4) In one embodiment, the power supply unit further includes a third power converter that converts AC power into power for charging the main battery. The third power converter is arranged in a different housing space than the housing spaces of the first and second power converters.

[0014] The first and second power converters can operate simultaneously with the third power converter. For example, during AC charging, when power from the main battery is supplied to the vehicle's auxiliary devices, the third power converter operates to charge the main battery, and the first power converter operates to convert the main battery power; the converted power is then supplied to the auxiliary devices. Alternatively, during AC charging, when AC power is supplied to the vehicle's auxiliary devices, the third power converter operates to charge the main battery, and the second power converter operates to convert the AC power; the converted power is then supplied to the auxiliary devices. By arranging the third power converter, which can operate simultaneously with the first and second power converters, in a different housing space than the housing spaces of the first and second power converters, thermal interference between the power converters can be reduced.

[0015] (5) In one embodiment, the controller controls a third power converter. The second power converter has a lower power capacity than the first power converter. During AC charging, when the power consumption of the auxiliary device is less than a threshold, the controller activates the third power converter to charge the main battery, activates the second power converter to supply power to the auxiliary device, and stops the first power converter.

[0016] (6), (7) In one embodiment, the controller controls a third power converter. The second power converter has a lower power capacity than the first power converter. During AC charging, when the power consumption of the auxiliary device exceeds a threshold, the controller activates the third power converter to charge the main battery, activates the first power converter to supply power to the auxiliary device, and stops the second power converter.

[0017] Using the configurations in each of (5) to (7) above, the controller determines which of the first and second power converters should be operated and which should be stopped based on whether the power consumption of the auxiliary device exceeds a threshold. The threshold is determined, for example, based on the power capacity of the second power converter. The power consumption of the second power converter is generally less than that of the first power converter. Considering power conversion efficiency, it is more desirable to operate the second power converter than to operate the first power converter when the power supplied from the second power converter can cover the power consumption of the auxiliary device. When the power consumption of the auxiliary device is less than the power capacity of the second power converter, power conversion efficiency can be further improved by operating the second power converter to supply power to the auxiliary device compared to operating the first power converter to supply power to the auxiliary device.

[0018] (8) In one embodiment, the vehicle is configured to perform DC charging of the main battery using DC power supplied from a DC power source outside the vehicle. The power supply unit also includes a relay for supplying DC power to the main battery. The relay is housed in a different housing space than the housing spaces of the first and second power converters and the third power converter.

[0019] With the above configuration, the relay is housed in a different space than the housing spaces of the first to third power converters. Therefore, thermal interference from the first to third power converters to the relay can be reduced.

[0020] The foregoing and other objects, features, aspects and advantages of this disclosure will become more apparent from the following detailed description of this disclosure when taken in conjunction with the accompanying drawings. Attached Figure Description

[0021] Figure 1 This is a block diagram illustrating an example configuration of a vehicle according to an embodiment.

[0022] Figure 2 This is a diagram illustrating the control of the power supply unit during vehicle operation.

[0023] Figure 3 This is a diagram used to illustrate the control of the power supply unit during AC charging.

[0024] Figure 4 This is a diagram used to illustrate the control of the power supply unit during AC charging.

[0025] Figure 5 This is a diagram used to illustrate the control of the power supply unit during DC charging.

[0026] Figure 6 This is a flowchart illustrating the control process of the power supply unit.

[0027] Figure 7 The operating status of the main DC / DC converter, the charging circuit, and the sub-DC / DC converter are displayed. Detailed Implementation

[0028] Embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. Furthermore, identical or corresponding elements in the drawings, which are labeled with the same reference numerals, will not be described again.

[0029] <Overall Configuration>

[0030] Figure 1This is a block diagram illustrating an example configuration of vehicle 1 according to this embodiment. Vehicle 1 according to Embodiment 1 is a pure electric vehicle. Vehicle 1 is capable of receiving power supplied from an external power source outside the vehicle and charging its onboard main battery; however, vehicle 1 is not limited to a pure electric vehicle. Vehicle 1 can be, for example, a plug-in hybrid electric vehicle or a fuel cell electric vehicle.

[0031] According to this embodiment, the vehicle 1 is configured to perform AC charging by receiving AC power supplied from a DC power source outside the vehicle 1 and charging the on-board main battery, and DC charging by receiving DC power supplied from a DC power source outside the vehicle 1 and charging the on-board main battery.

[0032] Vehicle 1 includes a battery pack 10, a power supply unit 20, a front power control unit (hereinafter also referred to as "Fr_PCU" 30), a low-voltage auxiliary device 40, a high-voltage auxiliary device 50, an AC input 60, a DC input 70, and a higher-level ECU (Electronic Control Unit) 100. Although vehicle 1 according to this embodiment is configured to drive the front wheels, when vehicle 1 is configured to drive all wheels, vehicle 1 also includes a rear power control unit (hereinafter also referred to as "Rr_PCU" 31).

[0033] The battery pack 10 is mounted on the vehicle 1 as the driving power source (i.e., power source) of the vehicle 1. The battery pack 10 includes a main battery 11, system main relays (hereinafter also referred to as "SMR") 12 and 13, and charging relays (hereinafter also referred to as "CHR") 14 and 15.

[0034] The main battery 11 is composed of a stack of multiple batteries. The batteries are, for example, secondary batteries such as nickel-metal hydride batteries or lithium-ion batteries. The batteries can be batteries with a liquid electrolyte between the positive and negative electrodes, or batteries with a solid electrolyte (all-solid-state batteries). The main battery 11 can be any rechargeable DC power source, and large-capacity capacitors can also be used.

[0035] SMRs 12 and 13 are electrically connected between the main battery 11 and power lines PL and NL, respectively. One end of SMR 12 is electrically connected to the positive terminal of the main battery 11, and the other end is electrically connected to power line PL. One end of SMR 13 is electrically connected to the negative terminal of the main battery 11, and the other end is electrically connected to power line NL. SMRs 12 and 13 are switched between open and closed states, for example, according to control signals from a higher-level ECU 100.

[0036] Power lines PL and NL electrically connect battery pack 10 to Fr_PCU 30. Power lines PL and NL are partially housed in power supply unit 20. Power lines PL and NL are equipped with noise-resistant ferrite cores 81 and 82. When Rr_PCU 31 is provided, power lines PL and NL are branched into power lines PL1 and NL1, respectively. Power lines PL1 and NL1 are electrically connected to Rr_PCU 31. Power lines PL1 and NL1 are equipped with ferrite cores 83. Each of ferrite cores 81 to 83 captures the magnetic field generated by high-frequency noise current and converts the captured magnetic field into heat, thereby reducing noise. Ferrite cores 81 to 83 are respectively housed in power supply unit 20.

[0037] Fr_PCU 30 converts the DC power supplied from the main battery 11 via power lines PL and NL into AC power and supplies the AC power to the motor generator (not shown). The motor generator is an AC rotary electric machine, and is, for example, a permanent magnet type synchronous motor with a rotor incorporating permanent magnets. The rotor of the motor generator is mechanically connected to the front wheel, which serves as the drive wheel, via a power transmission gear (not shown). Fr_PCU 30 includes, for example, an inverter for driving the motor generator and a converter for boosting the DC voltage supplied to the inverter to a level not less than the output voltage of the main battery 11.

[0038] When vehicle 1 also includes Rr_PCU 31, Rr_PCU 31 supplies AC power to a motor generator (not shown) having a rotor mechanically connected to the rear wheels via a power transmission gear.

[0039] CHR 14 and 15 are electrically connected between the main battery 11 and power lines APL1 and ANL1, respectively. One end of CHR 14 is electrically connected to the positive terminal of the main battery 11, and the other end is electrically connected to power line APL1. One end of CHR 15 is electrically connected to the negative terminal of the main battery 11, and the other end is electrically connected to power line ANL1. CHR 14 and 15 are switched between open and closed states, for example, according to control signals from a higher-level ECU 100.

[0040] Power lines APL1 and ANL1 electrically connect CHR 14 and 15 to an AC charger 22 (not shown) included in the power supply unit 20. When vehicle 1 also includes a solar charger 90, the solar charger 90 is electrically connected to power lines APL1 and ANL1. The solar charger 90 converts the electricity generated by the onboard solar panel (not shown) into charging power for the main battery 11 and supplies the charging power to power lines APL1 and ANL1. When CHR 14 and 15 are closed, the main battery 11 is charged using the power from the solar charger 90.

[0041] The power supply unit 20 houses and modularizes multiple on-board devices within a housing. Specifically, the power supply unit 20 includes a main DC / DC converter 21, an AC charger 22, a DC relay 25, a charging integrated ECU 26, and a housing 28. The housing 28 has multiple layers and houses the main DC / DC converter 21, the AC charger 22, the DC relay 25, and the charging integrated ECU 26. Fuse connectors 87 to 89 are disposed on the side surfaces of the housing 28. The arrangement of the on-board devices within the housing 28 will be described below.

[0042] The main DC / DC converter 21 is electrically connected between power lines PL, NL and power line EL. The main DC / DC converter 21 is electrically connected to power lines PL, NL via fuse 86. The main DC / DC converter 21 performs voltage conversion on the power supplied from the main battery 11 to power lines PL, NL and supplies the resulting power to power line EL. The power capacity (capability to supply current to power line EL) of the main DC / DC converter 21 is greater than the power capacity of the sub-DC / DC converter 24, which will be described below. The main DC / DC converter 21 corresponds to an example of the "first power converter" according to this disclosure.

[0043] The power line EL is electrically connected to the low-voltage auxiliary device 40 and the auxiliary battery (not shown). The low-voltage auxiliary device 40 is a device that operates using the power supplied to the power line EL. The low-voltage auxiliary device 40 includes, for example, various ECUs, lighting devices, audio devices, navigation devices, power steering devices, etc.

[0044] Power lines PL and NL are electrically connected to the high-voltage auxiliary device 50 via connectors provided on the side surface of the housing 28 of the power supply unit 20. The high-voltage auxiliary device 50 includes a water heater 51 and an air conditioner 52.

[0045] Water heater 51 is electrically connected to connector 87. Connector 87 is electrically connected to power lines PL and NL in housing 28 of power supply unit 20. Water heater 51 is a heater used to heat the interior of a vehicle. Water heater 51 is, for example, a PTC (Positive Temperature Coefficient) heater. Water heater 51 has, for example, pipes and heats water circulating in the pipes to indirectly heat the air.

[0046] Air conditioner 52 is electrically connected to connector 88. Connector 88 is electrically connected to power lines PL and NL in housing 28 of power supply unit 20. Air conditioner 52 includes a compressor and operates the compressor according to control signals from higher-level ECU 100 to regulate the air inside the vehicle.

[0047] The high-voltage auxiliary device 50 may also include an AC-100-V inverter 53 that supplies power to an on-board socket (not shown) located inside the vehicle 1. The AC-100-V inverter 53 is electrically connected to a connector 89. The connector 89 is electrically connected to power lines PL and NL in the housing 28 of the power supply unit 20. The AC-100-V inverter 53 converts the power supplied to the main battery 11 on the power lines PL and NL into power to be supplied to the on-board socket (e.g., AC 100V power) and outputs the converted power to the on-board socket.

[0048] AC charger 22 is electrically connected to battery pack 10 via power lines APL1 and ANL1. AC charger 22 is also electrically connected to AC inlet 60 via power lines APL2 and ANL2.

[0049] AC inlet 60 receives AC power supplied from an AC charging station (not shown) outside the vehicle 1. AC inlet 60 can be connected to a charging connector located at the end of the charging cable of the AC charging station. The AC power received by AC inlet 60 is supplied to AC charger 22 through power lines APL2 and ANL2.

[0050] The AC charger 22 includes a charging circuit 23 and a sub-DC / DC converter 24. In this embodiment, the charging circuit 23 and the sub-DC / DC converter 24 are arranged on different substrates and are electrically connected by power lines 27.

[0051] Charging circuit 23 includes a filter circuit (not shown), a PFC (Power Factor Correction) circuit, a smoothing capacitor, and a high-voltage DC / DC converter. The filter circuit is electrically connected to AC input 60 via fuse 84. Fuse 84 is configured to interrupt the current path when a current exceeding its rated current flows. Fuses 85 and 86, described below, also have the same configuration as fuse 84. However, the fuses are configured differently for their rated currents. The filter circuit removes noise contained in the AC power supplied from AC input 60 and outputs noise-free AC power to the PFC circuit. The PFC circuit rectifies and boosts the noise-removed AC power from the filter circuit and outputs the resulting AC power to the smoothing capacitor, and also makes the input current closer to a sine wave, thereby correcting the power factor. The PFC circuit can be any type of PFC circuit. The PFC circuit can be a rectifier without power factor correction. The smoothing capacitor smooths voltage fluctuations in the DC power received from the PFC circuit. The smoothed DC power is supplied to the high-voltage DC / DC converter and sub-DC / DC converter 24. The high-voltage DC / DC converter converts the voltage of the DC power smoothed by the smoothing capacitor into a voltage suitable for charging the main battery 11 (e.g., exceeding 200V), and then supplies this voltage to the power lines APL1, ANL1. The charging circuit 23 corresponds to an example of the "third power converter" according to this disclosure.

[0052] The sub-DC / DC converter 24 converts the voltage of the DC power smoothed by the smoothing capacitor into the voltage to be supplied to the low-voltage auxiliary device 40, and supplies the converted power to the power line EL. The sub-DC / DC converter 24 has a fuse 85 between the power line EL and the sub-DC / DC converter 24. The power capacity (ability to supply current to the power line EL) of the sub-DC / DC converter 24 is lower than that of the main DC / DC converter 21. The power consumption of the sub-DC / DC converter 24 is less than that of the main DC / DC converter 21. The sub-DC / DC converter 24 corresponds to an example of a "second power converter" according to this disclosure.

[0053] DC relay 25 is disposed between battery pack 10 and DC input 70. Specifically, one end of DC relay 25 is electrically connected to power lines PL and NL, and the other end is electrically connected to power lines CPL and CNL. Power lines CPL and CNL electrically connect DC input 70 to the other end of DC relay 25. DC relay 25 switches between open and closed states according to control signals from charging integrated ECU 26. When DC relay 25 is closed, power supplied from DC input 70 can be supplied to battery pack 10.

[0054] DC inlet 70 receives DC power supplied from a DC charging station (not shown) outside the vehicle 1. DC inlet 70 can be connected to a charging connector located at the front end of the charging cable of the DC charging station. The DC power received by DC inlet 70 is supplied to the battery pack 10 through DC relay 25.

[0055] Temperature sensors Ts are installed on the power lines CPL and CNL. The temperature sensors Ts detect the temperature of the power lines CPL and CNL and output a signal indicating the detection result to the charging integrated ECU 26 via the temperature detection line.

[0056] The charging integrated ECU 26 includes a CPU (Central Processing Unit), memory, and I / O ports (not shown). The memory includes ROM (Read Only Memory) and RAM (Random Access Memory) and stores programs executed by the CPU. The CPU deploys the program stored in ROM to RAM and executes it. Based on various signals input from the I / O ports and information stored in the memory, the CPU performs predetermined calculations and controls the main DC / DC converter 21, the AC charger 22 (charging circuit 23, sub-DC / DC converter 24), and the DC relay 25 based on the results of these calculations. Such control can be performed not only through software but also through specialized hardware (electronic circuitry).

[0057] A higher-level ECU 100 is, for example, an EV-ECU. The higher-level ECU 100 includes a CPU (not shown), memory, and I / O ports. The memory includes ROM and RAM and stores programs executed by the CPU. The CPU deploys the program stored in ROM to RAM and executes the program. The CPU performs predetermined calculations based on various signals input from the I / O ports and information stored in the memory, and controls each device based on the results of the calculations, causing the vehicle 1 to enter a desired state. For example, the CPU controls Fr_PCU 30, Rr_PCU 31, SMR 12, 13, CHR 14, 15, low-voltage auxiliary device 40, high-voltage auxiliary device 50, and solar charger 90. Such control can be handled not only by software but also by specialized hardware (electronic circuitry).

[0058] The higher-level ECU 100 and the charging integrated ECU 26 are configured to communicate with each other via a communication line. The charging integrated ECU 26, based on information from the higher-level ECU 100, controls the main DC / DC converter 21, the AC charger 22, and the DC relay 25.

[0059] As described above, the vehicle 1 configured as described above includes a power supply unit 20, in which multiple on-board devices (main DC / DC converter 21, AC charger 22, DC relay 25, and charging integrated ECU 26) are housed in a housing 28. The functions of the multiple on-board devices are integrated into the unit, thus saving more space and reducing costs compared to arranging multiple on-board devices separately.

[0060] However, when functions are integrated into a unit, multiple on-board devices are housed within the same housing 28, thus the problems associated with the heat generated in each on-board device can become significant. Specifically, the main DC / DC converter 21, charging circuit 23, and sub-DC / DC converter 24 may generate a significant amount of heat during operation. Therefore, when such devices are arranged adjacent to each other, the risk of failure may increase due to thermal interference between the devices. It is conceivable that the main DC / DC converter 21, charging circuit 23, and sub-DC / DC converter 24 could be arranged in different layers of housing 28. However, considering the ease of mounting the power supply unit 20 on the vehicle 1, it is necessary to prevent an increase in the height of the power supply unit 20 (the height of the vehicle in the vertical direction). Furthermore, each of the main DC / DC converter 21, charging circuit 23, and sub-DC / DC converter 24 has a large number of components and includes large-mass magnetic components, resulting in a heavier weight than any other on-board device. Therefore, the main DC / DC converter 21, the charging circuit 23 and the sub-DC / DC converter 24 need to be arranged in the lowest possible layer so that the center of gravity of the power supply unit 20 is located on the lower side of the housing 28.

[0061] Therefore, in this embodiment, the main DC / DC converter 21, the charging circuit 23, and the sub-DC / DC converter 24 are arranged in a layer on the lower side of the housing 28. The main DC / DC converter 21 and the sub-DC / DC converter 24 are then arranged in the same layer of the housing 28. The charging circuit 23 is then arranged in a different layer than the layers of the main DC / DC converter 21 and the sub-DC / DC converter 24. The charging integrated ECU 26 operates the main DC / DC converter 21 and the sub-DC / DC converter 24 in a mutually exclusive manner. In other words, the charging integrated ECU 26 operates one of the main DC / DC converter 21 and the sub-DC / DC converter 24 without operating the other, and does not operate the main DC / DC converter 21 and the sub-DC / DC converter 24 simultaneously. Thus, the amount of heat generated from the main DC / DC converter 21 and the sub-DC / DC converter 24 can be reduced more significantly compared to when the main DC / DC converter 21 and the sub-DC / DC converter 24 operate simultaneously. This can reduce thermal interference between the main DC / DC converter 21 and the sub-DC / DC converter 24 while they are arranged on the same layer of the housing 28.

[0062] The charging circuit 23 is arranged on a different layer than the main DC / DC converter 21 and the sub-DC / DC converter 24 because the charging circuit 23 may need to operate simultaneously with the main DC / DC converter 21 and the sub-DC / DC converter 24. The specific control of each during vehicle 1 operation, during AC charging, and during DC charging will be described below.

[0063] <Control during vehicle operation>

[0064] Figure 2 This is a diagram illustrating the control of the power supply unit 20 during the operation of vehicle 1. Figure 2 And what will be described below Figures 3 to 5 The main battery 11, power supply unit 20, low-voltage auxiliary device 40 and AC inlet 60 are schematically shown.

[0065] The housing 28 of the power supply unit 20 is made of, for example, aluminum. Multiple layers are defined by partition walls 29 within the housing 28. Specifically, when the power supply unit 20 is mounted on the vehicle 1, partition walls 29 extending in the longitudinal direction of the vehicle 1 are provided, and multiple layers are defined by these partition walls 29. In other words, when the power supply unit 20 is mounted on the vehicle 1, the multiple layers are formed to be stacked in the height direction of the vehicle 1. In this embodiment, the housing 28 has three layers. The bottom layer is also referred to as the "first layer," the middle layer as the "second layer," and the top layer as the "third layer." The term "layer" in this embodiment corresponds to an example of a "receiving space" according to this disclosure.

[0066] The partition wall 29 has a refrigerant passage through which refrigerant flows. Because the partition wall 29 has a refrigerant passage, each on-board unit housed in the housing 28 can be cooled. The partition wall 29 may have an insulating material instead of a refrigerant passage. Because the partition wall 29 has an insulating material, thermal interference between on-board units across layers can be reduced.

[0067] In this embodiment, the charging circuit 23 is arranged in the first layer. The main DC / DC converter 21 and the sub-DC / DC converter 24 are arranged in the second layer. The DC relay 25 and the charging integrated ECU 26 are arranged in the third layer. Although the charging circuit 23 and the sub-DC / DC converter 24 are included in the AC charger 22, as described above, by arranging the charging circuit 23 and the sub-DC / DC converter 24 on different substrates, the charging circuit 23 and the sub-DC / DC converter 24 can be arranged in different layers.

[0068] During the running of the vehicle 1, the charging integrated ECU 26 stops the AC charger 22 (charging circuit 23 and sub-DC / DC converter 24). The charging integrated ECU 26 operates the main DC / DC converter 21 to convert the power of the main battery 11 and supply the converted power to the low-voltage auxiliary device 40 (power line EL) as shown by the arrow AR1. During the running of the vehicle 1, the main DC / DC converter 21 and the sub-DC / DC converter 24 do not operate simultaneously, thus avoiding the problem of the amount of heat generated associated with the simultaneous operation of the main DC / DC converter 21 and the sub-DC / DC converter 24.

[0069] <Control during AC charging>

[0070] Figure 3 and Figure 4 are diagrams for explaining the control of the power supply unit 20 during AC charging. In the present embodiment, the charging integrated ECU 26 switches the control according to the power required by the low-voltage auxiliary device 40 (i.e., the power consumption of the low-voltage auxiliary device 40) required during AC charging. Figure 3 Shows the process of supplying power to the low-voltage auxiliary device 40 when the power consumption Pa of the low-voltage auxiliary device 40 is less than the threshold value Pth. Figure 4 Shows the process of supplying power to the low-voltage auxiliary device 40 when the power consumption Pa of the low-voltage auxiliary device 40 is not less than the threshold value Pth. The threshold value Pth is a value determined based on the power capacity of the sub-DC / DC converter 24 (the ability to supply power to the power line EL). The threshold value Pth can be appropriately set within a range lower than the power capacity of the sub-DC / DC converter 24.

[0071] When the power consumption Pa of the low-voltage auxiliary device 40 is less than the threshold value Pth, the charging integrated ECU 26 stops the main DC / DC converter 21 and operates the sub-DC / DC converter 24 to supply the power supplied from the AC inlet 60 to the low-voltage auxiliary device 40. The charging integrated ECU 26 divides the power supplied from the AC inlet 60 into the power to be supplied to the main battery 11 and the power to be supplied to the low-voltage auxiliary device 40 (power line EL). Specifically, the charging integrated ECU 26 operates the charging circuit 23 to convert the power supplied from the AC inlet 60 into the charging power of the main battery 11 and supply the converted power to the main battery 11 (arrow AR2). The charging integrated ECU 26 also operates the charging circuit 23 and the sub-DC / DC converter 24 to convert the power supplied from the AC inlet 60 into the power to be supplied to the low-voltage auxiliary device 40 and supply the converted power to the low-voltage auxiliary device 40 (arrow AR3).

[0072] When the power consumption Pa of the low-voltage auxiliary device 40 is not less than the threshold value Pth, the charging integrated ECU 26 stops the sub-DC / DC converter 24 and operates the main DC / DC converter 21, and supplies the power of the main battery 11 to the low-voltage auxiliary device 40. The charging integrated ECU 26 operates the charging circuit 23 to convert the power supplied from the AC inlet 60 into the charging power of the main battery 11, and supplies the converted power to the main battery 11 (arrow AR4). The charging integrated ECU 26 also operates the main DC / DC converter 21 to convert the power of the main battery 11 into the power to be supplied to the low-voltage auxiliary device 40, and supplies the converted power to the low-voltage auxiliary device 40 (arrow AR5).

[0073] When the power consumption Pa of the low-voltage auxiliary device 40 is less than the threshold value Pth, as described above, the charging integrated ECU 26 operates the sub-DC / DC converter 24 without operating the main DC / DC converter 21. When the power consumption Pa of the low-voltage auxiliary device 40 is not less than the threshold value Pth, the charging integrated ECU 26 does not operate the sub-DC / DC converter 24 but operates the main DC / DC converter 21. In this way, the main DC / DC converter 21 and the sub-DC / DC converter 24 do not operate simultaneously, thus avoiding the problem of the amount of heat generation associated with the simultaneous operation of the main DC / DC converter 21 and the sub-DC / DC converter 24.

[0074] The power consumption of the sub-DC / DC converter 24 is less than that of the main DC / DC converter 21. Thus, when the power consumption Pa of the low-voltage auxiliary device 40 is less than the threshold value Pth, that is, when the amount of power supplied from the sub-DC / DC converter 24 can cover the power consumption Pa of the low-voltage auxiliary device 40, by stopping the main DC / DC converter 21 and operating the sub-DC / DC converter 24, it is possible to reduce the reduction in the charging efficiency of the main battery 11 while supplying power to the low-voltage auxiliary device 40 (power line EL).

[0075] <Control during DC charging>

[0076] Figure 5 It is a diagram for explaining the control of the power supply unit 20 during DC charging.

[0077] During DC charging, the charging integrated ECU 26 stops the AC charger 22 (charging circuit 23 and sub-DC / DC converter 24). During DC charging, the charging integrated ECU 26 closes the DC relay 25. Therefore, power supplied from the DC inlet 70 is supplied to the main battery 11 via the DC relay 25 (arrow AR6). The charging integrated ECU 26 also operates the main DC / DC converter 21 to convert the power from the main battery 11 into power to be supplied to the low-voltage auxiliary device 40, and supplies the converted power to the low-voltage auxiliary device 40 (arrow AR7). During DC charging, the main DC / DC converter 21 and the sub-DC / DC converter 24 do not operate simultaneously, thus avoiding the heat generation problems associated with the simultaneous operation of the main DC / DC converter 21 and the sub-DC / DC converter 24.

[0078] <Processing performed by the charging integrated ECU>

[0079] Figure 6 This is a flowchart illustrating the control process of the power supply unit 20. Figure 6 The processing shown in the flowchart is repeated by the charging integrated ECU 26 for each control cycle. Although a flowchart will be given... Figure 6 The flowchart shown describes the situation where each step (hereinafter referred to as "S") is implemented by the charging integrated ECU 26 through software processing, but the step may be implemented in part or in whole by hardware (electronic circuitry) formed in the charging integrated ECU 26.

[0080] In S1, the charging integrated ECU 26 determines whether vehicle 1 is in motion. For example, the charging integrated ECU 26 can also determine whether vehicle 1 is in motion based on information received from a higher-level ECU 100. When it is determined that vehicle 1 is in motion ("Yes" at S1), the charging integrated ECU 26 moves the processing to S2. When it is determined that vehicle 1 is not in motion ("No" at S1), the charging integrated ECU 26 moves the processing to S3.

[0081] In S2, the charging integrated ECU 26 operates the main DC / DC converter 21 and stops the sub-DC / DC converter 24. By operating the main DC / DC converter 21, the charging integrated ECU 26 converts the power from the main battery 11 into power to be supplied to the low-voltage auxiliary device 40, and supplies the converted power to the low-voltage auxiliary device 40 (power line EL).

[0082] In S3, the charging integrated ECU 26 determines whether DC charging is in progress. For example, the charging integrated ECU 26 determines whether DC charging is in progress based on whether the charging connector is connected to the DC input 70. When it is determined that DC charging is in progress ("Yes" at D3), the charging integrated ECU 26 moves the process to S4. When it is determined that DC charging is not in progress ("No" at S3), the charging integrated ECU 26 moves the process to S5.

[0083] In S4, the charging integrated ECU 26 operates the main DC / DC converter 21 and stops the sub-DC / DC converter 24. The charging integrated ECU 26 operates the main DC / DC converter 21 to convert the power from the main battery 11 into power to be supplied to the low-voltage auxiliary device 40, and supplies the converted power to the low-voltage auxiliary device 40 (power line EL). The charging integrated ECU 26 keeps the DC relay 25 closed. Upon initiation of DC charging, the charging integrated ECU 26 switches the DC relay 25 from the open state to the closed state.

[0084] In S5, the charging integrated ECU 26 determines whether AC charging is in progress. For example, the charging integrated ECU 26 determines whether AC charging is in progress based on whether the charging connector is connected to the AC inlet 60. If it is determined that AC charging is in progress ("Yes" at S5), the charging integrated ECU 26 moves the process to S6. If it is determined that AC charging is not in progress ("No" at S5), the charging integrated ECU 26 moves the process back.

[0085] In step S6, the charging integrated ECU 26 determines whether the power consumption Pa of the low-voltage auxiliary device 40 is not less than the threshold Pth. If the power consumption Pa is less than the threshold Pth (S6 is "No"), the charging integrated ECU 26 moves the processing to step S7. If the power consumption Pa is not less than the threshold Pth (S6 is "Yes"), the charging integrated ECU 26 moves the processing to step S8.

[0086] In S7, the charging integrated ECU 26 stops the main DC / DC converter 21 and operates the sub-DC / DC converter 24. During AC charging, the charging integrated ECU 26 also operates the charging circuit 23. By operating the charging circuit 23 and the sub-DC / DC converter 24, the charging integrated ECU 26 converts the power supplied from the AC inlet 60 into power to be supplied to the low-voltage auxiliary device 40, and supplies the converted power to the low-voltage auxiliary device 40 (power line EL).

[0087] In S8, the charging integrated ECU 26 operates the main DC / DC converter 21 and stops the sub-DC / DC converter 24. During AC charging, the charging integrated ECU 26 also operates the charging circuit 23. By operating the charging circuit 23, the charging integrated ECU 26 converts the power supplied from the AC inlet 60 into power for charging the main battery 11 and supplies the converted power to the main battery 11. By operating the main DC / DC converter 21, the charging integrated ECU 26 converts the power from the main battery 11 into power to be supplied to the low-voltage auxiliary device 40 and supplies the converted power to the low-voltage auxiliary device 40 (power line EL).

[0088] Figure 7 The operating status of the main DC / DC converter 21, the charging circuit 23, and the sub-DC / DC converter 24 is shown. Figure 7 The diagram shows the operating status of the main DC / DC converter 21, the charging circuit 23, and the sub-DC / DC converter 24 during vehicle 1's driving, AC charging, and DC charging periods.

[0089] During the operation of vehicle 1, charging circuit 23 and sub-DC / DC converter 24 are stopped (not running), while main DC / DC converter 21 is running.

[0090] During AC charging, the operating states of the main DC / DC converter 21, charging circuit 23, and sub-DC / DC converter 24 vary according to the relationship between the power consumption Pa of the low-voltage auxiliary device 40 and the threshold Pth. When the power consumption Pa of the low-voltage auxiliary device 40 is less than the threshold Pth, the charging circuit 23 and the sub-DC / DC converter 24 operate, while the main DC / DC converter 21 stops. When the power consumption Pa of the low-voltage auxiliary device 40 is not less than the threshold Pth, the charging circuit 23 and the main DC / DC converter 21 operate, while the sub-DC / DC converter 24 stops.

[0091] During DC charging, charging circuit 23 and sub-DC / DC converter 24 stop, while main DC / DC converter 21 operates.

[0092] As described above, the power supply unit 20 mounted on the vehicle 1 according to this embodiment includes multiple on-board devices in the housing 28, specifically a main DC / DC converter 21, an AC charger 22, a DC relay 25, and a charging integrated ECU 26, and the functions of the multiple on-board devices are integrated. Because the functions of the multiple on-board devices are integrated into a single unit, space and cost can be significantly reduced compared to arranging the on-board devices individually.

[0093] The AC charger 22 includes a charging circuit 23 and a sub-DC / DC converter 24 disposed on different substrates. The charging circuit 23 is electrically connected to the sub-DC / DC converter 24 via a power line 27. The charging circuit 23 and the sub-DC / DC converter 24 can operate simultaneously, for example, during AC charging. Because the charging circuit 23 and the sub-DC / DC converter 24 are disposed on different substrates, they can be disposed in different layers of the housing 28. This avoids thermal interference caused by the simultaneous operation of the charging circuit 23 and the sub-DC / DC converter 24 disposed in the same layer.

[0094] The main DC / DC converter 21 and the sub-DC / DC converter 24 are arranged in the same layer of the housing 28. The main DC / DC converter 21 and the sub-DC / DC converter 24 operate in a mutually exclusive manner. In other words, the charging integrated ECU 26 does not allow the main DC / DC converter 21 and the sub-DC / DC converter 24 to operate simultaneously. Therefore, the amount of heat generated by the main DC / DC converter 21 and the sub-DC / DC converter 24 can be reduced more significantly compared to when they operate simultaneously.

[0095] Compared to arranging the main DC / DC converter 21 and the sub-DC / DC converter 24 in different layers, arranging the main DC / DC converter 21 and the sub-DC / DC converter 24, which can operate in a mutually exclusive manner, in the same layer of the housing 28 can further reduce the increase in the height of the power supply unit 20. This can improve the ease of mounting the power supply unit 20 on the vehicle 1.

[0096] The charging circuit 23 is arranged on a different layer than the main DC / DC converter 21 and the sub-DC / DC converter 24. The charging circuit 23 may need to operate simultaneously with the main DC / DC converter 21 and the sub-DC / DC converter 24. Therefore, arranging the charging circuit 23 on a different layer than the main DC / DC converter 21 and the sub-DC / DC converter 24 can reduce thermal interference caused by simultaneous operation.

[0097] The DC relay 25 and the charging integrated ECU 26 are arranged on a different layer than the main DC / DC converter 21, the charging circuit 23, and the sub-DC / DC converter 24, which generate a large amount of heat during operation. This reduces the thermal interference to the DC relay 25 and the charging integrated ECU 26 caused by the main DC / DC converter 21, the charging circuit 23, and the sub-DC / DC converter 24.

[0098] [Variation Example]

[0099] A description of an example in which multiple layers are defined by partition walls 29 in housing 28 has been given. When power supply unit 20 is mounted on vehicle 1, the multiple layers are formed to be stacked in the height direction of vehicle 1. However, multiple receiving spaces for accommodating onboard devices can be defined by partition walls 29, and how the receiving spaces are defined is not limited to the form in which the receiving spaces are stacked in the height direction of vehicle 1.

[0100] For example, when the power supply unit 20 is mounted on the vehicle 1, multiple accommodating spaces can be defined by providing a partition wall 29 extending in the height direction of the vehicle 1. Furthermore, when the power supply unit 20 is mounted on the vehicle 1, the partition wall 29 extending in the longitudinal direction of the vehicle 1 and the partition wall 29 extending in the height direction of the vehicle 1 can be provided together to define multiple accommodating spaces.

[0101] In the above case, the main DC / DC converter 21 and the sub-DC / DC converter 24 arranged in the same housing space can also operate in a mutually exclusive manner, thus achieving a similar effect to the embodiment.

[0102] Although this disclosure has been described and illustrated in detail, it should be clearly understood that this disclosure is by way of illustration and example only and should not be used in a limiting manner. The scope of this disclosure is to be interpreted by the terms of the appended claims.

Claims

1. Power supply unit, including: First power converter; Second power converter; A controller that controls the first power converter and the second power converter; as well as A housing having multiple receiving spaces defined by partition walls, the housing accommodating the first power converter, the second power converter, and the controller, wherein... The first power converter and the second power converter are arranged in the same housing space of the housing. The controller causes the first power converter and the second power converter to operate in a mutually exclusive manner. The power supply unit is mounted on a vehicle configured to perform AC charging, which utilizes AC power supplied from an external AC power source to charge the main battery mounted on the vehicle. The first power converter converts the power from the main battery into power to supply auxiliary devices mounted on the vehicle. The second power converter will convert the power supplied from the AC power source into the power to be supplied to the auxiliary device. The power supply unit also includes a third power converter that converts the AC power into power for charging the main battery. The third power converter is arranged in a different housing space than the housing spaces of the first power converter and the second power converter. The controller controls the third power converter. The second power converter has a lower power capacity than the first power converter, and During the AC charging process, when the power consumption of the auxiliary device is less than a threshold, the controller activates the third power converter to charge the main battery, activates the second power converter to supply power to the auxiliary device, and stops the first power converter.

2. The power supply unit according to claim 1, wherein, During the AC charging process, when the power consumption of the auxiliary device exceeds the threshold, the controller activates the third power converter to charge the main battery, activates the first power converter to supply power to the auxiliary device, and stops the second power converter.

3. Power supply unit, including: First power converter; Second power converter; A controller that controls the first power converter and the second power converter; as well as A housing having multiple receiving spaces defined by partition walls, the housing accommodating the first power converter, the second power converter, and the controller, wherein... The first power converter and the second power converter are arranged in the same housing space of the housing. The controller causes the first power converter and the second power converter to operate in a mutually exclusive manner. The power supply unit is mounted on a vehicle configured to perform AC charging, which utilizes AC power supplied from an external AC power source to charge the main battery mounted on the vehicle. The first power converter converts the power from the main battery into power to supply auxiliary devices mounted on the vehicle. The second power converter will convert the power supplied from the AC power source into the power to be supplied to the auxiliary device. The power supply unit also includes a third power converter that converts the AC power into power for charging the main battery. The third power converter is arranged in a different housing space than the housing spaces of the first power converter and the second power converter. The controller controls the third power converter. The second power converter has a lower power capacity than the first power converter, and During the AC charging process, when the power consumption of the auxiliary device exceeds a threshold, the controller activates the third power converter to charge the main battery, activates the first power converter to supply power to the auxiliary device, and stops the second power converter.

4. The power supply unit according to any one of claims 1 to 3, wherein, The vehicle is configured to perform DC charging of the main battery using DC power supplied from a DC power source outside the vehicle. The power supply unit also includes a relay for supplying the DC power to the main battery, and The relay is housed in a different housing space than the housing spaces of the first power converter, the second power converter, and the third power converter.

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