Electric power control device for a vehicle

Abstract

The present application provides a power control device for a vehicle, which can continue charging a storage battery and running the vehicle even when a temperature detection function is damaged. To solve the above problem, the IPU 3 includes: a storage battery that supplies electric power to a drive unit of the vehicle; a temperature sensor that detects a temperature of the storage battery; a current sensor that detects a current of the storage battery; a voltage sensor that detects a voltage of the storage battery; a contactor that blocks the flow of the current from the storage battery and the flow of the current to the storage battery; and a storage battery ECU that, when the temperature detection function of the temperature sensor is damaged, calculates a power value of the storage battery based on a current detection result obtained by the current sensor and a voltage detection result obtained by the voltage sensor, and causes the contactor to act to block the flow of the current from the storage battery and the flow of the current to the storage battery when the calculated power value exceeds a certain value and exceeds a certain time.

Description

Technical Field

[0001] This invention relates to an electrical control device for a vehicle. Background Technology

[0002] In recent years, research and development related to batteries that help improve energy efficiency has been carried out in order to ensure that more people have access to suitable, reliable, sustainable and advanced energy.

[0003] For example, a vehicle power control device is disclosed that, in a vehicle equipped with a battery, a temperature sensor monitors the rate of temperature rise of electrically connected components, and performs specific control when the rate of temperature rise of the electrically connected components exceeds a reference value (e.g., see Patent Document 1). According to this power control device, the battery can be charged even when the rate of temperature rise of the electrically connected components exceeds the reference value.

[0004] [Previous Technical Documents]

[0005] (Patent Documents)

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-140827 Summary of the Invention

[0007] [The problem the invention aims to solve]

[0008] However, the Automotive Safety Integrity Level (ASIL) now includes provisions related to battery overheating. Even if the temperature detection function malfunctions, it is necessary to detect battery overheating to protect the battery. Therefore, in vehicles equipped with conventional electrical control systems, battery charging must be stopped and the vehicle must be stopped when the temperature detection function malfunctions.

[0009] The present invention was made in view of the above-mentioned problems, and its object is to provide a vehicle power control device that can continue to charge the battery and drive the vehicle even when the temperature detection function is damaged.

[0010] [Technical means to solve the problem]

[0011] (1) The power control device (e.g., the Intelligent Power Unit (IPU) 3) of the vehicle (e.g., vehicle 1) of the present invention comprises: a battery (e.g., battery 30) for supplying power to the drive unit of the vehicle (e.g., drive unit 2); a temperature sensor (e.g., temperature sensor 31) for detecting the temperature of the battery; a current sensor (e.g., current sensor 33) for detecting the current of the battery; a voltage sensor (e.g., voltage sensor 32) for detecting the voltage of the battery; an interrupting means (e.g., contactors 34b, 34c) for interrupting the flow of current from the battery and the flow of current toward the battery; and a control means (e.g., an electronic control unit for the battery). Unit (ECU) 35) When the aforementioned temperature sensor is damaged, the power value of the aforementioned battery is calculated based on the current detection result obtained by the aforementioned current sensor and the voltage detection result obtained by the aforementioned voltage sensor. When the calculated power value exceeds a certain value and exceeds a certain time, the aforementioned blocking means is activated to block the flow of current from the aforementioned battery and the flow of current toward the aforementioned battery.

[0012] According to the vehicle power control device of the invention in (1), when the temperature sensor is damaged, the control means calculates the battery power value based on the current detection result obtained by the current sensor and the voltage detection result obtained by the voltage sensor. When the calculated power value exceeds a certain value and exceeds a certain time, the blocking means is activated to block the flow of current from the battery and the flow of current toward the battery. Thus, even when the temperature sensor is damaged, the battery overheating can be prevented, so there is no need to stop the charging of the battery and the driving of the vehicle to avoid overheating. Therefore, the vehicle power control device according to the invention in (1) can continue to charge the battery and drive the vehicle even when the temperature detection function is damaged.

[0013] (2) The electric control device of the vehicle of the invention of (1) may also include a cooling means (e.g., the water cooling mechanism described below (illustration omitted)), which cools the aforementioned battery, and the aforementioned specific value and the aforementioned specific time are set based on the heating characteristics of the aforementioned battery and the cooling characteristics of the aforementioned cooling means.

[0014] The vehicle power control device according to (2) is able to effectively prevent excessive heating of the battery because the specific values ​​and specific times for the conditions for the blocking means to operate are set based on the heating characteristics of the battery and the cooling characteristics of the cooling means.

[0015] (The effect of the invention)

[0016] According to the present invention, a vehicle electrical control device can be provided that allows for continued battery charging and vehicle operation even when the temperature detection function is damaged. Furthermore, the present invention further contributes to improving energy efficiency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram illustrating the structure of a vehicle equipped with an IPU according to an embodiment of the present invention.

[0018] Figure 2 This is a flowchart illustrating the high-voltage blocking process in the IPU.

[0019] Figure 3 This is a diagram showing an example of the current value that is a condition for the contactor to operate. Detailed Implementation

[0020] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0021] First, use Figure 1 The structure of a vehicle 1 equipped with an IPU (Intelligent Power Unit) 3 according to an embodiment of the present invention will be described. Figure 1 This is a schematic diagram showing the structure of a vehicle 1 equipped with an IPU3 according to an embodiment of the present invention.

[0022] like Figure 1 As shown, vehicle 1 includes a drive unit 2, an IPU 3, a charger 4, and a plug 5, etc. That is, vehicle 1 in this embodiment is a plug-in hybrid electric vehicle.

[0023] Drive unit 2 uses the electricity supplied by IPU3 to propel vehicle 1. Drive unit 2 includes, for example, an engine and motor as power sources, as well as a fuel injection electronic control unit (FI-ECU) and a power control unit (PCU) that control them.

[0024] IPU3 includes the drive battery pack for drive unit 2 and functions as the power control device for vehicle 1. Specifically, IPU3 includes multiple batteries 30, multiple temperature sensors 31, multiple voltage sensors 32, current sensors 33, multiple contactors 34a, 34b, 34c, battery ECU 35, and water cooling mechanism (not shown).

[0025] The storage battery 30 is a high-voltage storage battery that is charged by the charger 4 and supplies power to the drive unit 2 by discharging. In this embodiment, the storage battery 30 is, for example, a large-capacity storage battery composed of multiple battery cells made of lithium-ion secondary batteries connected in series.

[0026] Temperature sensor 31 functions as a temperature sensor to detect the temperature of battery 30. In this embodiment, multiple temperature sensors 31 are provided, for example, one is provided in each stack of multiple battery cells to detect the temperature of each stack.

[0027] The voltage sensor 32 functions as a voltage sensor for detecting the voltage of the battery 30. In this embodiment, the voltage sensor 32 is, for example, a cell voltage sensor (CVS). One voltage sensor 32 is provided in each of the plurality of stacks included in the battery 30 to detect the voltage of each stack.

[0028] The current sensor 33 functions as a current sensor for detecting the current of the battery 30. In this embodiment, the current sensor 33 is, for example, composed of an initial state of charge (ISOC) sensor.

[0029] Contactor 34a operates during startup, while contactors 34b and 34c operate during vehicle operation and battery charging, in addition to startup. Contactors 34b and 34c are the positive and negative contactors, respectively, blocking the flow of current from and towards the battery 30. Specifically, contactors 34b and 34c, with high voltage, block the power supply from the battery 30 to the drive unit 2, and also block the supply of regenerative power from the drive unit 2 to the battery 30. Furthermore, contactors 34b and 34c, with high voltage, block the power supply from the charger 4 (not shown), which is connected to an external power supply device via plug 5, to the battery 30.

[0030] The battery ECU 35 centrally controls the IPU 3. The battery ECU 35 determines whether the temperature detection function of the temperature sensor 31 is damaged. If the temperature detection function of some temperature sensors 31 is damaged, the battery ECU 35 determines that the temperature detection function of the temperature sensor 31 is not missing and utilizes the temperature detection function of the remaining temperature sensors 31. That is, if the temperature detection function of multiple temperature sensors 31 is damaged, the battery ECU 35 determines that the temperature detection function of the temperature sensor 31 is damaged.

[0031] Specifically, when the temperature sensor 31 detects an abnormal value, the battery ECU 35 detects a fault in the temperature sensor 31 and determines that the temperature detection function of the temperature sensor 31 is damaged. Whether the detection value of the temperature sensor 31 is abnormal can be determined based on the charging and discharging history of the battery 30, etc.

[0032] Furthermore, when the temperature detection function of the temperature sensor 31 fails, the battery ECU 35 calculates the power value of the battery 30 based on the current detection result obtained by the current sensor 33 and the voltage detection result obtained by the voltage sensor 32. Then, when the calculated power value exceeds a certain value (e.g., 12kW) and exceeds a certain time (e.g., 5 seconds), the battery ECU 35 actuates the contactors 34b and 34c to block the flow of current from the battery 30 and the flow of current toward the battery 30.

[0033] In addition, regardless of whether the temperature detection function of the temperature sensor 31 is damaged, the battery ECU 35 controls the power of the battery 30 to not exceed the aforementioned specific value (e.g., 12kW).

[0034] The specific values ​​and timings that enable the battery ECU 35 to operate the contactors 34b and 34c are appropriately set based on the heating characteristics of the battery 30 and the cooling characteristics of the water-cooling mechanism (not shown). These specific values ​​and timings will be described in detail below.

[0035] The charger 4 is connected to an external power supply device (not shown) via a plug 5, thereby charging the battery 30.

[0036] The water-cooling mechanism (not shown) functions as a cooling means to cool the heated battery 30. The water-cooling mechanism is, for example, located below the battery 30 to cool the battery 30.

[0037] Next, use Figure 2 The high-voltage blocking process in IPU3 is explained. Figure 2 This is a flowchart illustrating the high-voltage blocking process in IPU3.

[0038] like Figure 2 As shown, the high-voltage blocking process in IPU3 includes a temperature detection function failure determination step S1, a high-voltage blocking determination step S2, and a high-voltage blocking step S3. This high-voltage blocking process in IPU3 is executed simultaneously with the IG-ON (automotive ignition) setting of vehicle 1.

[0039] In the temperature detection function failure determination step S1, the battery ECU 35 determines whether the temperature detection function of the temperature sensor 31 is damaged. When the temperature detection function of the temperature sensor 31 is damaged (if "yes" in step S1), the process proceeds to the high voltage interruption determination step S2. When the temperature detection function of the temperature sensor 31 is not damaged (if "no" in step S1), the temperature detection function failure determination step S1 is repeated.

[0040] In the high-voltage blocking determination step S2, the battery ECU 35 calculates the power value of the battery 30 based on the current detection result obtained by the current sensor 33 and the voltage detection result obtained by the voltage sensor 32, and determines whether the calculated power value exceeds a specific value (e.g., 12kW) and exceeds a specific time (e.g., 5 seconds). When the power value calculated by the battery ECU 35 exceeds the above-mentioned specific value and exceeds the above-mentioned specific time (if "yes" in step S2), the process proceeds to the high-voltage blocking step S3. When the power value calculated by the battery ECU 35 does not exceed the above-mentioned specific value or does not exceed the above-mentioned specific time (if "no" in step S2), the high-voltage blocking determination step S2 is repeated.

[0041] In the high-voltage blocking step S3, the battery ECU 35 actuates contactors 34b and 34c to block the flow of current from and toward the battery 30 with a high voltage (e.g., a voltage of 12 kW or higher). After blocking, the process ends.

[0042] Next, use Figure 3 The current values ​​required to operate contactors 34b and 34c are explained. Figure 3 This is a diagram showing an example of the current value required to operate contactors 34b and 34c.

[0043] like Figure 3 As shown, regardless of whether the temperature detection function of the temperature sensor 31 is damaged, the battery ECU 35 will interrupt the high voltage of the battery 30 by blocking a current of 60A or more. Based on this premise, the power value (e.g., 12kW) required to reach the safe upper limit temperature (e.g., 80 degrees Celsius) for continuous charging and discharging without cooling is set as a specific value as a condition for actuating the contactors 34b and 34c. At this time, the specific time is set to 5 seconds.

[0044] According to this embodiment, the following effects are achieved.

[0045] According to IPU3, when the temperature detection function of temperature sensor 31 fails, battery ECU 35 calculates the power value of battery 30 based on the current detection result obtained by current sensor 33 and the voltage detection result obtained by voltage sensor 32. When the calculated power value exceeds a certain value and exceeds a certain time, contactors 34b and 34c are activated to block the flow of current from and toward battery 30 with high voltage. Therefore, even when temperature sensor 31 fails, overheating of battery 30 can be prevented, and thus, there is no need to stop charging battery 30 and driving vehicle 1 to avoid overheating. Therefore, according to IPU3 of vehicle 1 in this embodiment, even when the temperature detection function fails, charging of battery 30 and driving of vehicle 1 can continue.

[0046] Furthermore, according to IPU3, the specific values ​​and specific times for the conditions to activate contactors 34b and 34c are set based on the heating characteristics of the battery 30 and the cooling characteristics of the water-cooling mechanism (not shown). Therefore, according to this embodiment, overheating of the battery 30 can be reliably prevented.

[0047] Furthermore, the present invention is not limited to the above-described embodiments, and all variations and improvements within the scope of achieving the objectives of the present invention are included in the present invention.

[0048] For example, the above embodiments apply the invention to plug-in hybrid electric vehicles, but it is not limited thereto. It can be widely applied to vehicles that include high-voltage batteries that supply power to the vehicle's drive unit.

[0049] Figure Labels

[0050] 1 vehicle

[0051] 2 drive units

[0052] 3IPU (Power Control Unit)

[0053] 30 storage batteries

[0054] 31 Temperature sensor

[0055] 32 Voltage Sensor

[0056] 33 Current Sensor

[0057] 34a, 34b, 34c contactors (interception method)

[0058] 35 Battery ECU (Control Method)

[0059] 4 Chargers

[0060] 5 plugs

[0061] S1 Temperature Detection Function Fault Determination Steps

[0062] S2 High Voltage Interruption Judgment Steps

[0063] S3 High Voltage Interception Procedure

Claims

1. An electrical control device for a vehicle, comprising: The battery supplies power to the vehicle's drive unit; A temperature sensor is used to detect the temperature of the aforementioned battery. A current sensor detects the current of the aforementioned battery; A voltage sensor detects the voltage of the aforementioned battery; Interception measures, which block the flow of current from the aforementioned battery and the flow of current toward the aforementioned battery; Cooling means, wherein the cooling means cools the aforementioned storage battery; and, The control mechanism, when the aforementioned temperature sensor fails, calculates the battery's power value based on the current detection results obtained from the aforementioned current sensor and the voltage detection results obtained from the aforementioned voltage sensor. When the calculated power value exceeds a certain value for a certain period of time, the aforementioned blocking mechanism is activated to block the flow of current from and toward the aforementioned battery. The aforementioned specific values ​​and the aforementioned specific time are set based on the heating characteristics of the aforementioned battery and the cooling characteristics of the aforementioned cooling method.

Images