System for implementing vehicle accessory load control and power stability

Abstract

A system in a vehicle includes a memory to store values obtained for a battery supplying current to one or more loads. The values include a battery state of charge. A processor obtains a measured battery current from a battery current sensor and a measured total current from a current sensor at a battery center directly supplying current to the one or more loads, obtains a generator current or a direct current-direct current (DC-DC) converter current from the measured total current and the battery current, determines a maximum available current as a sum of a maximum available battery current and the generator current or the DC-DC converter current, and stops supplying current to one or more of the one or more loads based on a comparison of the maximum available current and a current draw through the one or more loads.

Description

Technical Field

[0001] This disclosure relates to vehicle accessory load control and power stability. Background Technology

[0002] Vehicles (such as cars, trucks, construction equipment, and farm equipment) can be gasoline or diesel powered, or electric or hybrid. Regardless of the power source of the vehicle's propulsion system, the power source for accessory loads is typically a battery. In gasoline, diesel, or hybrid vehicles, a battery and a generator to charge the battery can be used. In electric vehicles, a battery and a DC-DC converter to charge the battery can be used. The maximum available output power of the battery and generator, or the battery and DC-DC converter, determines the power stability of the load. Therefore, it is desirable to provide vehicle accessory load control and power stability. Summary of the Invention

[0003] In one exemplary embodiment, the system in the vehicle includes a memory for storing values ​​obtained by the battery for supplying current to one or more loads of the vehicle. These values ​​include the battery's state of charge (SoC). The system also includes a processor for obtaining a measured battery current from a current sensor of the battery and a measured total current from a current sensor at the battery center, which directly supplies current to the one or more loads, to obtain a generator current or DC-DC converter current from the measured total current and the battery current, to determine a maximum available current as the sum of the maximum available battery current and the generator current or DC-DC converter current, and to stop supplying current to the one or more loads based on a comparison of the maximum available current with the current drawn through the one or more loads.

[0004] In addition to one or more features described herein, the processor is based on the battery's internal resistance R. internal and battery internal voltage V oc Maximum available battery current I bmax Determined as:

[0005]

[0006] In addition to one or more features described herein, the processor obtains the battery's internal resistance R from a lookup table based on the current values ​​of SoC, p, temperature, and voltage. internal and battery internal voltage V oc The value of .

[0007] In addition to one or more of the features described herein, the vehicle is gasoline or diesel powered, and the generator current is obtained by subtracting the battery current from the measured total current.

[0008] In addition to one or more of the features described herein, the vehicle is a hybrid vehicle, and the DC-DC converter current is obtained by subtracting the battery current from the measured total current.

[0009] In addition to one or more of the features described herein, the vehicle is an electric vehicle, and the DC-DC converter current is obtained by subtracting the battery current from the measured total current.

[0010] In addition to one or more features described herein, the processor is associated with a priority for each of one or more loads.

[0011] In addition to one or more features described herein, the processor, based on a comparison of the maximum available current with the current drawn through one or more loads, indicates that the maximum available current is less than the current drawn through one or more loads, and stops supplying current to one or more of the one or more loads.

[0012] In addition to one or more features described herein, the processor selects one or more of the one or more loads based on priorities associated with one or more of the one or more loads.

[0013] In addition to one or more features described herein, the processor continues to supply current to other loads besides those one or more of the one or more loads, based on other loads among the one or more loads that affect vehicle safety.

[0014] In another exemplary embodiment, a non-transitory computer-readable medium stores instructions that, when processed by a processor, cause the processor to implement a method in a vehicle. The method includes obtaining a measured battery current from a current sensor of the battery and a measured total current from a current sensor at a battery center configured to directly supply current to one or more loads. The method also includes obtaining a generator current or a DC-DC converter current from the measured total current and the measured battery current, determining a maximum available current as the sum of the maximum available battery current and the generator current or DC-DC converter current, and controlling the cessation of current supply to one or more of the one or more loads based on a comparison of the maximum available current with current drawn through the one or more loads.

[0015] In addition to one or more features described herein, the method includes a method based on the battery's internal resistance R. internal and battery internal voltage V oc Maximum available battery current I bmax Determined as:

[0016]

[0017] In addition to one or more features described herein, the method includes obtaining the battery's internal resistance R from a lookup table based on the current values ​​of SoC, p, temperature, and voltage. internal and battery internal voltage V oc The value of .

[0018] In addition to one or more features described herein, the method includes obtaining the generator current by subtracting the battery current from the total current measured in a gasoline or diesel-powered vehicle.

[0019] In addition to one or more features described herein, the method includes obtaining the DC-DC converter current by subtracting the battery current from the total current measured in the hybrid vehicle.

[0020] In addition to one or more features described herein, the method includes, for example, subtracting the battery current from the total current measured in the electric vehicle to obtain the DC-DC converter current.

[0021] In addition to one or more features described herein, the method includes associating a priority with each of one or more loads.

[0022] In addition to one or more features described herein, the method includes indicating, based on a comparison of the maximum available current with the current drawn through one or more loads, that the maximum available current is less than the current drawn through one or more loads, and stopping the supply of current to one or more of the one or more loads.

[0023] In addition to one or more features described herein, the method includes selecting one or more of the one or more loads based on a priority associated with one or more of the one or more loads.

[0024] In addition to one or more features described herein, the method includes continuing to supply current to other loads among the one or more loads besides the one or more loads that affect vehicle safety, based on other loads among the one or more loads that affect vehicle safety.

[0025] The above-described features and advantages, as well as other features and advantages of this disclosure, will become readily apparent from the following detailed description when taken in conjunction with the accompanying drawings. Attached Figure Description

[0026] Other features, advantages, and details appear only by way of example in the following detailed description, which is illustrated in the accompanying drawings:

[0027] Figure 1 This is a block diagram of a vehicle that implements accessory load control and power stability according to one or more embodiments;

[0028] Figure 2This is a schematic diagram of an exemplary power distribution system for a vehicle that implements accessory load control and power stability according to one or more embodiments;

[0029] Figure 3 This is a schematic diagram of an exemplary power distribution system for a vehicle that implements accessory load control and power stability according to one or more embodiments; and

[0030] Figure 4 This is a flowchart of a method for implementing accessory load control and power stability in a vehicle according to one or more embodiments. Detailed Implementation

[0031] The following description is exemplary in nature only and is not intended to limit this disclosure, its application, or use. It should be understood that in all the drawings, corresponding reference numerals denote the same or corresponding parts and features.

[0032] Embodiments of the systems and methods detailed herein relate to vehicle accessory load control and power stability. As previously described, accessory loads (e.g., air conditioning, infotainment systems, navigation) are powered by batteries (e.g., 12-volt (V) batteries) that are recharged by a generator in gasoline or diesel vehicles, and by batteries that are charged via a DC-DC converter in hybrid and electric vehicles. Maximum available output power refers to the output of the battery combined with the generator or DC-DC converter. This maximum available output power indicates whether all loads of the vehicle can be supported. Otherwise, mitigation measures may be necessary. For example, if the maximum available output power is known to be insufficient, predictive load shedding can be implemented to ensure that more critical loads (e.g., those related to safety systems) are powered, while less critical loads (e.g., those related to convenience systems) are shut down.

[0033] A battery's maximum current capability is a function of its voltage, state of charge (SoC), and temperature. Typically, a current sensor is located on the battery. The sensed battery current and voltage represent the battery's maximum available output power at any given time. However, generators or DC-DC converters may not have associated current sensors. Therefore, the maximum available output power of the generator or DC-DC converter, and consequently the total maximum available output power of the load, is often unknown. According to one or more embodiments, a current sensor is included in a battery power center (BEC) that includes switches and fuses to control the current supply to various loads. As detailed, this current sensor is used to determine the maximum available output power available to the load to facilitate accessory load control and ensure power stability.

[0034] According to an exemplary embodiment, Figure 1This is a block diagram of a vehicle 100 implementing accessory load control and power stability. An exemplary vehicle 100 is an automobile 101, and according to alternative embodiments, it may be a conventional (i.e., gasoline or diesel driven), hybrid, or electric vehicle 100. That is, vehicle 100 may include a port 102 for drawing in gasoline or diesel fuel. Alternatively (in the case of an EV) or additionally (in the case of a plug-in hybrid), vehicle 100 may include a port 103 for an external battery charger. A power distribution system 110 of vehicle 100 and a load 130 powered by the power distribution system 110 are shown. The power distribution system 110 may include a controller 115.

[0035] Furthermore, vehicle 100 may include vehicle controller 120, which controls various aspects of vehicle operation and may additionally control various aspects of power distribution system 110. For example, vehicle 100 may include a semi-autonomous or autonomous system. The controller 115 of power distribution system 110 and vehicle controller 120 may include processing circuitry, which may include application-specific integrated circuits (ASICs), electronic circuitry, processors (shared, dedicated, or grouped) and memory executing one or more software or firmware programs, combinational logic circuitry, and / or other suitable components providing the aforementioned functionality. The memory of the processing circuitry may include a non-transitory computer-readable medium storing instructions that, when processed by one or more processors of the processing circuitry, implement the processes described in detail herein.

[0036] Figure 2 This is a schematic diagram of an exemplary power distribution system 110 of a vehicle 100 that implements accessory load control and power stability according to one or more embodiments. Controller 115 and / or vehicle controller 120 are indicated and can obtain values ​​individually or in combination, as detailed. Figure 2 The exemplary vehicle 100 shown with the exemplary power distribution system 110 is a gasoline or diesel powered vehicle 100. Thus, the vehicle 100 includes a starter motor 250 connected via a relay 240 to a battery 210 and a generator 230 to charge the battery 210.

[0037] In addition to being used by the starter motor 250, the battery 210 supplies power to one or more loads 130 (denoted as L1 to Ln) when the vehicle 100 is started. The controller 115 and / or the vehicle controller 120 can use the battery's internal voltage V. oc (i.e., open-circuit voltage) and battery internal resistance R internal The value will be the maximum available battery current I from battery 210. bmax and battery power P bmax Determined as:

[0038] [Equation 1]

[0039] [Equation 2]

[0040] Battery internal voltage V oc and the internal resistance R of the battery internal The value can be based on the SoC of battery 210, voltage (V) Batt The current known values ​​of current and temperature are obtained from a lookup table. Memory included in controller 115 or vehicle controller 120 can store these current values ​​and the lookup table. Integrated battery sensor 220 can be used to sense the battery current I flowing from battery 210. Batt Based on the battery current I Batt Given the known current voltage of battery 210, the current battery output power P of battery 210. bout It can be determined as:

[0041] [Equation 3]

[0042] Generator 230 charges battery 210. As mentioned earlier, there is no direct sensing of the generator current I flowing from generator 230. Gen Instead of a dedicated current sensor, according to one or more embodiments, current sensor 260 is included in BEC 270, which controls the power supply to load 130. Controller 115 may also be part of BEC 270. Current sensor 260 measures the power supplied by the battery current I. Batt and generator current I Gen The total current I generated total Therefore, the generator current I Gen It can be determined as:

[0043] [Equation 4]

[0044] Based on the generator current I Gen and the known generator voltage V Gen The current generator output power P of generator 230 gout It can be determined by controller 115 and / or vehicle controller 120 as:

[0045] [Equation 5]

[0046] Maximum available generator current I from generator 230 gmax and generator power P gmax It can be obtained from lookup tables, mathematical functions, or suppliers, and is based on the generator voltage V of generator 230. Gen Temperature, magnetic field duty cycle, and rotational speed.

[0047] Figure 3 This is a schematic diagram of an exemplary power distribution system 110 for a vehicle 100 that implements accessory load control and power stability according to one or more embodiments. Controller 115 and / or vehicle 120 are indicated and can obtain values ​​individually or in combination, as detailed. Figure 3 The exemplary vehicle 100 shown, featuring an exemplary power distribution system 110, is an EV. The power distribution system 110 includes a high-voltage rechargeable energy storage system (RESS) 310, which may include, for example, one or more battery packs. A traction power inverter module (TPIM) 320 converts energy from the RESS 310 to drive one or more motors in the drivetrain, thereby propelling the electric vehicle 100. A DC-DC converter 330 converts energy from the RESS 310 to charge a battery 210, which provides constant power and constant resistance to loads 130 L1 to Ln. As shown, one or more high-voltage loads 130 Lx can be powered by the RESS 310 without requiring the DC-DC converter 330.

[0048] For reference Figure 2 The discussion and Figure 3 As shown, the integrated battery sensor 220 can be used to sense the battery current I flowing out of the battery 210. Batt Therefore, Equation 3 can be related to the battery voltage V. Batt The values ​​are used together to determine the current output power P of battery 210. bout This determination can be made by controller 115 and / or vehicle controller 120. Additionally, the maximum available battery current I from battery 210... bmax and battery power P bmax The internal voltage V of the battery can be determined using equations 1 and 2. oc and the internal resistance R of the battery internal The value is based on the SoC of battery 210 and the voltage (V) Batt The current known values ​​of temperature are obtained from the lookup table.

[0049] Similarly, as referenced Figure 2 The discussion and Figure 3 As shown, current sensor 260 is included in BEC 270, which controls the power supply from battery 210 to load 130. Current sensor 260 measures the power supplied by battery current I. Batt and the DC-DC converter current I from DC-DC converter 330 DCDC The total current I generated total Therefore, the DC-DC converter current I DCDC It can be determined as:

[0050] [Equation 6]

[0051] The current I from the DC-DC converter DCDC and the known DC-DC converter voltage V DCDC The current DC-DC converter output power P of DC-DC converter 330 dout It can be determined by controller 115 or vehicle controller 120 as follows:

[0052] [Equation 7]

[0053] DC-DC converter current I from DC-DC converter 330 dmax and DC-DC converter power P dmax It can be obtained from a lookup table, mathematical function, or supplier based on known values.

[0054] Figure 4 This is a flowchart of a method 400 for implementing accessory load control and power stability in a vehicle 100 according to one or more embodiments. These processes may be performed by the controller 115 of the power distribution system 110, by the vehicle controller 120, or by a combination of both. At block 410, obtaining the current value and the battery and total current measurements refers to obtaining the reference... Figure 2 and Figure 3 The values ​​discussed are: specifically, the current, power, maximum available current, and maximum available power of battery 210 and generator 230, or battery 210 and DC-DC converter 330. The maximum available current is the maximum available battery current I in Equation 1. bmax and the generator current I from Equation 4 Gen (In the case of gas-powered vehicle 100) or the DC-DC converter current I from Equation 6. DCDC The sum of .

[0055] At box 420, check if the maximum available current is less than the current draw from load 130. If the maximum available current is greater than or equal to the current draw from load 130, controller 115 or vehicle controller 120 takes no action and can continue monitoring the value at box 410. If the maximum available current is less than the current draw from load 130, load management, including load shedding, can be implemented at box 430.

[0056] At box 430, load management is performed if the check at box 420 indicates that the current drawn through load 130 exceeds the maximum available current. At box 430, load management may include shutting down one or more loads 130 based on their priority level. That is, loads 130 may be associated with priority levels (e.g., high or low). Alternatively, loads 130 may be categorized from those belonging to high-priority, safety-related functions (e.g., battery management, braking systems) to those belonging to lower-priority, convenience-related functions (e.g., heated seats). One or more lower-priority loads 130 may be shut down when the maximum available current is less than the current drawn from the currently operating load 130.

[0057] The terms “a” and “an” do not indicate a limitation of quantity, but rather the presence of at least one of the referenced items. The term “or” means “and / or” unless the context clearly indicates otherwise. Throughout the specification, a reference to “an aspect” means that a particular element described in connection with that aspect (e.g., a feature, structure, step, or characteristic) is included in at least one aspect described herein and may or may not be present in other aspects. Furthermore, it should be understood that the described elements may be combined in any suitable manner across the aspects. Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0058] While the foregoing disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and equivalents can replace its elements without departing from its scope. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of this disclosure without departing from its essential scope. Therefore, it is intended that this disclosure be limited to the specific embodiments disclosed, but will include all embodiments falling within its scope.

Claims

1. A system in a vehicle, comprising: A memory configured to store values ​​obtained by the battery for supplying current to one or more loads of the vehicle, including the battery's state of charge; and The processor is configured to obtain a measured battery current from a current sensor in the battery and a measured total current from a current sensor at the battery center, the battery center being configured to directly supply current to one or more loads to obtain a generator current or DC-DC converter current from the measured total current and the battery current, determine the maximum available current as the sum of the maximum available battery current and the generator current or DC-DC converter current, and stop supplying current to one or more loads based on a comparison of the maximum available current with the current drawn through one or more loads.

2. The system of claim 1, wherein the processor is configured based on the internal resistance R of the battery. internal and battery internal voltage V oc To maximize the available battery current I bmax Determined as: ,and The processor is configured to obtain the battery's internal resistance R from a lookup table based on the current values ​​of the state of charge, battery power, temperature, and voltage. internal and battery internal voltage V oc The value of .

3. The system of claim 1, wherein the vehicle is gasoline or diesel powered, and the generator current is obtained by subtracting the battery current from the measured total current.

4. The system of claim 1, wherein the vehicle is a hybrid vehicle and the DC-DC converter current is obtained by subtracting the battery current from the measured total current, or the vehicle is an electric vehicle and the DC-DC converter current is obtained by subtracting the battery current from the measured total current.

5. The system of claim 1, wherein the processor is configured to associate a priority with each of the one or more loads, the processor is configured to stop supplying current to one or more of the one or more loads based on a comparison of the maximum available current with the current drawn through the one or more loads indicating that the maximum available current is less than the current drawn through the one or more loads, the processor is configured to select one or more of the one or more loads based on the priority associated with one or more of the one or more loads, and the processor is configured to continue supplying current to other loads in the one or more loads besides the one or more of the one or more loads based on other loads in the one or more loads that affect vehicle safety.

6. A non-transitory computer-readable medium configured to store instructions, which, when processed by a processor, cause the processor to implement a method in a vehicle, the method comprising: The battery current is measured from the battery's current sensor, and the total current is measured from the current sensor at the battery center, which is configured to supply current directly to one or more loads. The generator current or DC-DC converter current is obtained from the measured total current and the measured battery current; The maximum available current is determined as the sum of the maximum available battery current and the generator current or DC-DC converter current; and Based on a comparison between the maximum available current and the current drawn through one or more loads, control stops supplying current to one or more of the one or more loads.

7. The non-transitory computer-readable medium of claim 6, wherein the method comprises based on the internal resistance R of the battery. internal and battery internal voltage V oc Maximum available battery current I bmax Determined as: ,and This method includes obtaining the battery's internal resistance R from a lookup table based on the current values ​​of the state of charge, battery power, temperature, and voltage. internal and battery internal voltage V oc The value of .

8. The non-transitory computer-readable medium of claim 6, wherein the method comprises subtracting the battery current from the total current measured in a gasoline or diesel-powered vehicle to obtain the generator current.

9. The non-transitory computer-readable medium of claim 6, wherein the method comprises subtracting the battery current from the measured total current in a hybrid vehicle to obtain the DC-DC converter current, or the method comprises subtracting the battery current from the measured total current in an electric vehicle to obtain the DC-DC converter current.

10. The non-transitory computer-readable medium of claim 6, wherein the method includes associating a priority with each of the one or more loads, the method includes indicating, based on a comparison of a maximum available current with current drawn through the one or more loads, that the maximum available current is less than current drawn through the one or more loads, stopping the supply of current to one or more of the one or more loads, the method includes selecting one or more of the one or more loads based on the priority associated with one or more of the one or more loads, and the method includes continuing to supply current to other loads of the one or more loads besides one or more of the one or more loads based on other loads of the one or more loads that affect vehicle safety.

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