A charge-based passenger cabin remote thermal management method

Abstract

The application discloses a kind of based on charging cabin remote thermal management method, in advance by setting preheating / cold time parameter in charging scene;During preheating process, BMS continuously monitors monomer battery voltage and temperature, and timely adjusts charging current according to the change of parameter, when Vmax reaches monomer voltage threshold 1, BMS will adjust charging current from I Bat_r When temperature is less than time threshold 1 from greater than time threshold 1, BMS will trigger the operation of whole vehicle starting air conditioner and current adjustment I1;When satisfying SOC≤SOC threshold 1 and T>time threshold 1, enter normal charging process, normally request charging current I Bat_r When Vmax reaches voltage threshold 2 and T is greater than time threshold 2, BMS requests charging current to reduce, and enters discharge state.This charging current control strategy based on multi-parameter dynamic adjustment can accurately respond to complex chemical changes and performance changes in battery charging process, effectively protect battery from overcharge damage, prolong battery life, while improving charging efficiency.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle battery thermal management technology, and more specifically to a charging-based remote thermal management method for passenger cabins. Background Technology

[0002] In hot summer weather, the passenger cabin temperature rises rapidly when the vehicle is stationary, requiring drivers and passengers to endure a period of high temperatures after boarding until the air conditioning cools the cabin. Conversely, in cold winter weather, the passenger cabin temperature drops when the vehicle is stationary, requiring drivers and passengers to endure a period of cold temperatures after boarding. This affects driver comfort and passenger experience. Therefore, many automakers have introduced remote thermal management systems for their vehicle cabins.

[0003] While existing remote thermal management systems for passenger cabins can achieve preheating / cooling functions, the energy comes from the power battery, meaning the battery is not fully charged at departure, affecting vehicle range and posing a risk of overcharging. Some systems set thresholds to control the start and end of charging during cabin heating to prevent overcharging. However, there are still instances where heating continues after charging is complete, requiring battery energy to heat the cabin and preventing full charging. Prolonged inability to fully charge reduces vehicle range and affects SOC calibration, increasing the risk of vehicle breakdown. Therefore, we propose a charging-based remote thermal management method for passenger cabins. Summary of the Invention

[0004] This invention provides a charging-based remote thermal management method for passenger cabins, aiming to address the aforementioned shortcomings of existing remote thermal management systems for passenger cabins.

[0005] The present invention adopts the following technical solution:

[0006] A charging-based remote thermal management method for passenger cabins includes the following steps:

[0007] Step 1: Before charging begins, the user sets the preheating / cooling start time and the air conditioner's operating time.

[0008] Step 2: After the vehicle charging gun is successfully connected and the charging start signal is detected, the BMS continuously determines whether the preheating / cooling setting time has been reached, and whether the air conditioning working time setting is not zero and does not exceed the vehicle system limit.

[0009] Step 3: During the charging process, the BMS determines the validity of the preheating / cooling function signal transmitted from the vehicle, and at the same time monitors whether the communication between itself and the vehicle is normal.

[0010] Step 4: Specific judgments and current adjustments during the preheating / cooling process; specifically including: triggering adjustments to SOC, remaining preheating / cooling time T, and highest individual cell voltage V each time the BMS performs a status update. max If the time threshold T is satisfied, the preheating / cooling process is directly initiated. The BMS responds to the VCU's request for air conditioning current, and the BMS requests a charging current of I=I. Bat_r +I p -I0, where: I0 is the minimum charging current of the charging pile, I Bat_r The battery is configured to look up the corresponding current based on temperature and SOC. If SOC > SOC threshold 1, Vmax > single cell voltage threshold 1, and T > time threshold 1, the battery enters a current-reduction waiting process with a charging request current of I0. If SOC > SOC threshold 1, Vmax < single cell voltage threshold 1, and T > time threshold 1, the battery enters a preheating / cold preparation process with a charging request current of I1, where I1 = (1 - SOCmax) * nominal capacity / (T / 60), SOCmax is the current SOC, and nominal capacity is the capacity (Ah) released by a fully charged battery at room temperature when discharged at 1C current to reach the termination voltage. If SOC ≤ SOC threshold 1 and T > time threshold 1, the battery enters a normal charging process with a normal charging request current of I1. Bat_r .

[0011] The triggering condition for step three above is either to trigger periodically at time intervals or to trigger immediately upon receiving a status update signal for the entire vehicle.

[0012] In step three above, if communication between the BMS and the vehicle is interrupted, the pre-cooling / heating function will be invalid by default, and the charging will continue normally until the vehicle is fully charged before ending the charging process.

[0013] The cabin remote thermal management method of the present invention further includes step five: process jump; specifically including:

[0014] When the vehicle is in the cabin preheating / cooling process, it meets V max If the voltage threshold is ≥2, then enter the second battery discharge process. The second battery discharge process specifically requests a charging current of max(I0, Ip-I0), lasts for T1 time, and then returns to the cabin preheating / cooling process. If the time threshold 2 < T ≤ time threshold 1 and the air conditioning power and the remaining preheating / cooling time T are valid, then enter the normal charging process.

[0015] When a vehicle is in the flow reduction waiting process, if T ≤ time threshold 1, it enters the cabin preheating / cooling process; and if V ≤ time threshold 1, it enters the cabin preheating / cooling process. max If the voltage threshold is ≥2, then the battery discharge process one is entered. Specifically, the battery discharge process one requests a charging current of max(I0, Ip-I0) and the whole vehicle is turned on for preheating / cooling.

[0016] When the vehicle is in the preheating / cold preparation process, it meets V max If the voltage threshold is greater than or equal to 1, the current reduction waiting process will be initiated; if the time threshold is less than or equal to 1, the cabin preheating / precooling process will be initiated.

[0017] When the charging process is in progress, if the time threshold 2 < T ≤ time threshold 1 and the air conditioning power and the remaining time T for the scheduled heating are valid, the cabin preheating / cooling process will begin; if the SOC > SOC threshold 1 and T > time threshold 1 and the air conditioning power and the remaining time T for the preheating / cooling are valid, the current reduction waiting process will begin; if the charge is full, the charging process will be exited directly and the charging will end.

[0018] When the vehicle enters the battery discharge process one, the following process is performed: 1) When the vehicle determines that the cell voltage exceeds the voltage threshold 2 and the preheating / cooling task is effective, the preheating / cooling is started; 2) When the vehicle determines that the cell voltage is lower than the voltage threshold 3 or the preheating / cooling task is ineffective, the preheating / cooling is exited, and the passenger cabin preheating / cooling process is entered if T≤time threshold 1.

[0019] The above time threshold 1 is preferably set to 60 minutes; time threshold 2 is preferably set to 15 minutes; single-cell voltage threshold 1 is preferably set to 3.5V; single-cell voltage threshold 2 is preferably set to 3.6V; single-cell voltage threshold 3 is preferably set to 3.4V; and SOC threshold 1 is preferably 90%.

[0020] As can be seen from the above description of the present invention, compared with the prior art, the present invention has the following advantages:

[0021] I. This invention employs a multi-parameter dynamic adjustment charging current strategy. At the end of the charging process, the charging current is dynamically adjusted based on a combination of the highest single-cell voltage and the remaining preheating / cooling time T, even initiating a discharge state. For example, when the highest single-cell voltage reaches a voltage threshold of 2 and T is greater than a time threshold of 2, the BMS requests a reduction in the charging current and initiates a discharge state. This multi-parameter dynamic adjustment charging current control strategy can accurately address the complex chemical and performance changes during battery charging, effectively protecting the battery from overcharging damage, extending battery life, and improving charging efficiency.

[0022] Second, when the vehicle is connected to the grid for charging, preheating of the passenger compartment utilizes grid power, avoiding the use of the vehicle's own battery energy. For example, in cold weather, preheating the battery compartment reduces the burden on the vehicle's battery to power the heating system, thus saving battery power and increasing the vehicle's driving range. Compared to turning on heating or cooling equipment while the vehicle is in motion, preheating during charging allows the use of off-peak electricity rates, reducing energy costs.

[0023] Third, it enhances vehicle operational efficiency. Vehicles can be pre-processed according to a predetermined schedule, eliminating the need to adjust the temperature after passengers board. For example, bus companies can preheat or pre-cool vehicles while charging overnight, ensuring they are ready for immediate use the next day, reducing waiting time and improving vehicle turnover efficiency. For car-sharing and other operating models, maintaining a consistently good internal environment improves vehicle utilization and increases operating revenue.

[0024] Fourth, improving passenger experience means ensuring the vehicle's interior reaches a comfortable temperature before passengers board. For example, in hot summers, the vehicle is pre-cooled, so passengers feel refreshed upon entering; in cold winters, the interior is warm and inviting, enhancing passenger comfort. Providing a comfortable environment for public transportation vehicles such as buses and rail transit helps attract more passengers to choose public transport. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating an embodiment of the present invention. Detailed Implementation

[0026] The following reference Figure 1 Specific embodiments of the present invention will be described below. Many details are described below to provide a comprehensive understanding of the invention; however, those skilled in the art can implement the invention without these details. Well-known components, methods, and processes will not be described in detail hereafter.

[0027] This embodiment provides a charging-based remote thermal management method for passenger cabins, referring to... Figure 1 This includes the following steps:

[0028] Step 1: Pre-charging setup

[0029] Users must manually set the preheating / cooling start time and air conditioner operating time. They must ensure that the input format is correct and the time value is within a reasonable range (e.g., 0-24 hour format, with the duration not exceeding the preheating / cooling and air conditioner operating time corresponding to the longest battery charging time).

[0030] Before the vehicle is parked and powered off, the driver enters the scheduled departure time and air conditioning parameters, and the vehicle stores this information.

[0031] Step 2: Information transmission and preliminary judgment during charging.

[0032] The vehicle continuously sends the remaining time T for cabin preheating / cooling and the air conditioning power requirement. The BMS continuously determines whether the preheating / cooling setting has been activated (based on the vehicle clock) and whether the air conditioning operating time setting is not zero and does not exceed the vehicle system limit.

[0033] Once the vehicle's charging gun is successfully connected and a charging start signal is detected, the entire vehicle is triggered to perform this judgment and information processing operation.

[0034] Step 3: Continuous judgment of BMS

[0035] The BMS determines whether the preheating / cooling function is valid based on the validity signal (such as specific high / low levels or message signals) transmitted from the vehicle. At the same time, it monitors whether the communication between itself and the vehicle is normal. If the communication is interrupted, the preheating / cooling is invalid by default (a certain communication timeout can be set, for example, if no valid signal is received within 5 seconds, it is considered a communication interruption). The system will then charge normally until it is fully charged and then end the charging process.

[0036] During the charging process, the BMS is periodically triggered to make this judgment at certain time intervals, or it is triggered immediately when the vehicle status update signal is received.

[0037] Step 4: Specific Judgments and Current Adjustments in the Preheating / Cooling Process

[0038] SOC determination: By accurately monitoring the battery power within the BMS, the current SOC value is compared with a set threshold.

[0039] T-judgment: The time from the start of preheating / cooling, recorded by the vehicle's built-in clock or charging timing module, is compared with a time threshold.

[0040] Single cell voltage Vmax determination: Relying on the BMS to monitor the single cell voltage in real time, it is determined whether the single cell voltage threshold has been reached.

[0041] Each time the BMS performs a status update, it triggers a judgment on SOC, T, and individual cell voltage. If T ≤ time threshold 1 (judgment condition 1), it directly enters the preheating / cooling process. The BMS responds to the VCU's request for air conditioning current, and the BMS requests a charging current of I = I0. Bat_r +I p -I0, where: I0 is the minimum charging current of the charging pile; I Bat_r The corresponding current for the battery is determined by looking up a table based on temperature and SOC.

[0042] If SOC > SOC threshold 1, Vmax > single cell voltage threshold 1, and T > time threshold 1 (judgment condition 2), then the current reduction waiting process is entered, and the charging request current is I0.

[0043] If SOC > SOC threshold 1, Vmax < single cell voltage threshold 1, and T > time threshold 1 (judgment condition 3), then the preheating / cold preparation process is entered, and the requested charging current is I1, where: I1 = (1-SOCmax) * nominal capacity / (T / 60), SOCmax is the current SOC, and nominal capacity is the capacity (Ah) that a fully charged battery at room temperature discharges at a 1C current to reach the termination voltage.

[0044] If SOC ≤ SOC threshold 1 and T > time threshold 1 (judgment condition 4), the normal charging process begins, and the normal charging current I is requested. Bat_r .

[0045] Step 5: Process Redirection

[0046] When the vehicle is in the cabin preheating / cooling process, it meets V max If the voltage threshold is ≥2, then proceed to battery discharge process 2; if the time threshold 2 < T ≤ time threshold 1 and the received air conditioner power and the remaining time T for scheduled heating are valid, then proceed to normal charging process.

[0047] When a vehicle is in the flow reduction waiting process, if T ≤ time threshold 1, it enters the cabin preheating / cooling process; and if V ≤ time threshold 1, it enters the cabin preheating / cooling process. max If the voltage threshold is ≥2, then proceed to battery discharge process 1.

[0048] When the vehicle is in the preheating / cold preparation process, it meets V max If the voltage threshold is greater than or equal to 1, the current reduction waiting process will begin; if the time threshold is less than or equal to 1, the cabin preheating / cooling process will begin.

[0049] When the charging process is in progress, if the time threshold 2 < T ≤ time threshold 1 and the received air conditioning power and the remaining time T for preheating are valid (judgment condition 6), the cabin preheating / precooling process will begin; if the SOC > SOC threshold 1 and T > time threshold 1 and the received air conditioning power and the remaining time T for preheating / precooling are valid (judgment condition 5), the current reduction waiting process will begin; if the battery is fully charged, the charging process will end directly (if the individual cell voltage reaches the charging cutoff voltage during charging, the charging process will end directly).

[0050] The following are the detailed processes of battery discharge process 1 and battery discharge process 2:

[0051] Battery discharge process 1: Request charging current of max(I0, Ip-I0) and start vehicle preheating / precooling.

[0052] 1) The vehicle should initiate preheating / precooling when the individual cell voltage exceeds voltage threshold 2 and the preheating / precooling task is effective. 2) The vehicle should exit preheating / precooling when the individual cell voltage is below voltage threshold 3 or the preheating / precooling task is ineffective, and enter the cabin preheating / precooling process if T ≤ time threshold 1.

[0053] Battery discharge process 2: Request charging current of max(I0, Ip-I0), after a period of time (i.e., duration T1), return to the cabin preheating / precooling process, I p This is the current required for heating or cooling the air conditioner; if T ≤ time threshold 2, then the normal charging process begins.

[0054] The above time threshold 1 is preferably set to 60 minutes; time threshold 2 is preferably set to 15 minutes; single-cell voltage threshold 1 is preferably set to 3.5V; single-cell voltage threshold 2 is preferably set to 3.6V; single-cell voltage threshold 3 is preferably set to 3.4V; and SOC threshold 1 is preferably 90%.

[0055] The above are merely specific embodiments of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial modifications made to the present invention using this concept shall be considered as infringing upon the protection scope of the present invention.

Claims

1. A charge-based passenger cabin remote thermal management method, characterized by, Comprising the following steps, Step one: before charging starts, the user sets the preheating / cold starting time and the air conditioner working time; Step two: when the vehicle charging gun is successfully connected and the charging start signal is detected, the BMS continuously judges whether the preheating / cold setting time has arrived, and whether the air conditioner working time setting is not zero and does not exceed the vehicle system limit; Step three: during the charging process, the BMS judges whether the preheating / cold function effectiveness signal transmitted by the whole vehicle is valid, and monitors whether the communication between itself and the whole vehicle is normal. Step four: specific judgment and current adjustment in preheating / cold flow; including: each time the BMS updates the state to trigger the judgment of SOC, the remaining time T of preheating / cold and the highest single cell voltage V max , if T≤time threshold 1, directly enter the preheating / cold flow, the BMS responds to the air conditioning current requested by the VCU, the BMS requests the charging current I=I Bat_r +I p -I0, wherein: I0 is the minimum charging current of the charging pile, I Bat_r is the current corresponding to the temperature and SOC of the battery according to the table, I p is the current required for air conditioning heating or refrigeration; if SOC>SOC threshold 1 and Vmax>single cell voltage threshold 1 and T>time threshold 1, enter the current reduction waiting flow, the charging request current is I0; if SOC>SOC threshold 1 and Vmax Bat_r < single cell voltage threshold 1 and T>time threshold 1, enter the preheating / cold preparation flow, request the charging current I1, wherein: I1=(1-SOCmax)*nominal capacity / (T / 60), SOCmax is the current SOC, and the nominal capacity is the capacity (Ah) discharged when the battery is fully charged at room temperature with 1c current and reaches the termination voltage; if SOC≤SOC threshold 1 and T>time threshold 1, enter the normal charging flow, and the normal request charging current is I Bat_r .

2. A charge-based cabin remote thermal management method as in claim 1, characterized by: The trigger condition of step three is periodic triggering according to time interval or triggering immediately when receiving the state update signal of the whole vehicle.

3. A charge-based cabin remote thermal management method as in claim 1, characterized by: In step three, if the communication between BMS and the whole vehicle is interrupted, the preheating / cold is invalid by default, and the charging is directly normal to full charge and then ends.

4. A charge-based cabin remote thermal management method as in claim 1, wherein, It also includes step five: process jump; specifically including: When the vehicle is in the cabin preheating / cooling process, V max ≥ voltage threshold 2, enter the battery discharge process two, which is specifically to request the charging current to be max (I0, Ip-I0), and after T1 time, return to the cabin preheating / cooling process; meet time threshold 2 Teffective, enter the normal charging process; When the vehicle is in the descending flow waiting process, if T≤time threshold 1 is met, the passenger cabin preheating / cold flow process is entered; and if V max ≥voltage threshold 2 is met, the battery discharging process one is entered, which is specifically that the request charging current is max(I0, Ip-I0) and the whole vehicle is started to preheat / cold. When the vehicle is in the pre-heat / cool preparation procedure, V max ≥ voltage threshold 1, the vehicle enters the flow reduction waiting procedure; and when T≤ time threshold 1, the vehicle enters the passenger cabin pre-heat / pre-cool procedure. When normally in the charging process, if the time threshold 2 < T ≤ time threshold 1 is met and the air conditioner power and the remaining heating time T are valid, the cabin preheating / cold process is entered; if SOC > SOC threshold 1 and T > time threshold 1 and the air conditioner power and the preheating / cold remaining time T are valid, the current reduction waiting process is entered; if full, the charging process is directly exited and the charging is ended.

5. A charge-based cabin remote thermal management method as in claim 4, characterized by: When the vehicle enters the battery discharge process, the following processes are performed: 1) the whole vehicle judges that the single cell voltage exceeds the voltage threshold 2 and the preheating / cold task is valid, and the preheating / cold is started; 2) the whole vehicle judges that the single cell voltage is lower than the voltage threshold 3 or the preheating / cold task is invalid, and the preheating / cold is exited, and T ≤ time threshold 1 is met to enter the cabin preheating / cold process.

6. A charge-based cabin remote thermal management method as in claim 5, characterized by: The time threshold 1 is set to 60 minutes; the time threshold 2 is set to 15 minutes; the single cell voltage threshold 1 is set to 3.5V; the single cell voltage threshold 2 is set to 3.6V; the single cell voltage threshold 3 is set to 3.4V; and the SOC threshold 1 is 90%.

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