A control method of a range extended vehicle

Abstract

The application provides a control method of a range-extender vehicle. First, the vehicle controller receives the state of the range-extender APU, judges the high-pressure state, and receives the remaining battery capacity SOC and the current vehicle speed. Then, it is determined whether to start the range-extender APU. Finally, the battery demand power value is distributed to the range-extender APU according to the remaining battery capacity SOC and the current vehicle operating condition. The application distributes the demand power according to the remaining battery capacity SOC and the vehicle operating condition, which can effectively reduce the discharge power of the power battery while ensuring the vehicle power, and the remaining battery capacity SOC as the condition for distributing the demand power can effectively ensure the safety of the power battery.

Description

Technical Field

[0001] This invention relates to a control method for range-extended electric vehicles, belonging to the field of electric vehicle manufacturing technology. Background Technology

[0002] With the increasingly severe energy and environmental situation, and the promotion of electric vehicles, the driving range of electric vehicles has become a key research focus for automotive developers. However, the high cost and short lifespan of current batteries severely hinder the development of electric vehicles. The emergence of range-extended electric vehicles has effectively alleviated people's anxiety about the driving range of electric vehicles. When the power battery has sufficient charge, the range extender is turned off, and the vehicle operates in pure electric mode. When the power battery is low on charge, the range extender is turned on to assist in driving the vehicle, and the vehicle enters range-extended mode. Summary of the Invention

[0003] The purpose of this invention is to provide a control method for range-extended electric vehicles. By allocating the required power based on the remaining battery charge (SOC) and operating conditions of the range-extended vehicle through the vehicle controller, the range-extended electric vehicle can improve its economy to a certain extent while ensuring safety and power.

[0004] This invention is achieved through the following technical solution: a control method for a range-extended electric vehicle, characterized in that: the required power is allocated to the remaining battery charge (SOC) and operating conditions of the range-extended electric vehicle through the vehicle controller, including the following specific steps:

[0005] Step 1: Receive the status of the range extender APU from the vehicle controller to determine if there is a fault. If there is a fault, disable the range extender APU and perform fault detection. If the APU is not faulty, proceed to the next step.

[0006] Step 2: The vehicle controller determines whether the vehicle's high-voltage status is READY or NO READY. If the vehicle status is READY, the next step is executed.

[0007] Step 3: The vehicle controller receives the remaining battery charge (SOC) and the current vehicle speed. When the battery charge (SOC) is less than the preset calibration value x and the vehicle speed is greater than the calibration value v, or when the battery charge (SOC) is less than the preset calibration value z and the vehicle speed is not equal to zero, the next step is executed.

[0008] Step 4: Based on the range extender APU status, vehicle high voltage status, remaining battery SOC, and current vehicle speed from the above steps, decide whether to activate the range extender APU.

[0009] Step 5: After the range extender APU is turned on, the power distribution control method for the range-extended vehicle is executed, and the required power is allocated according to the remaining battery charge (SOC) and the vehicle operating conditions obtained in the previous steps.

[0010] Furthermore, in step 1, if the range extender APU malfunctions, the vehicle will be controlled to operate in pure electric mode, and the start of the range extender APU will be prohibited.

[0011] Furthermore, in step 3, when the battery charge SOC is less than the preset calibration value x=70% and the vehicle speed is greater than the calibration value v=20km / h, or when the battery charge SOC is less than the preset calibration value z=20% and the vehicle speed is not equal to zero, the next step is executed.

[0012] Furthermore, in step 3, by setting a MAP table with corresponding parameters and obtaining the corresponding data by looking up the table, the specific steps include:

[0013] Step 3.1: Within the rated power range of the range extender, select n power points with intervals and low fuel consumption rates as the operating points of the range extender APU.

[0014] Step 3.2: Based on the vehicle speed and the power point in Step 3.1, set the vehicle speed-power MAP table. Pspd can be obtained by looking up the table based on the current vehicle speed.

[0015] Step 3.3: Set the throttle opening-MAP table according to the throttle pedal opening and the power point in Step 3.1, and obtain Pacc by looking up the table through the vehicle controller according to the current throttle pedal opening;

[0016] Step 3.4: Based on the remaining battery SOC and the power point setting SOC-power MAP table in step 3.1, the Psoc can be obtained by looking up the table based on the current SOC.

[0017] Furthermore, select power points P that have lower fuel consumption rates near 40%, 60%, 80%, and 100% of the range extender's rated power. A P B P C P D This serves as the operating point for the range extender APU.

[0018] Furthermore, in step 5, the current vehicle speed, current accelerator pedal travel, and remaining battery charge (SOC) are received through the vehicle controller; the required power value is allocated based on the remaining battery charge (SOC), the current vehicle speed, and the accelerator pedal travel.

[0019] Furthermore, when the battery charge SOC is less than the preset calibration value x but not less than the preset calibration value y, the power request sent by the vehicle controller (VCU) to the range extender (APU) is PAPU = min{ P spd P acc When the battery SOC is less than the preset calibration y, the APU power is set to PAPU = max{ P acc PSOC}; Based on the vehicle's latest SOC, vehicle speed, and accelerator pedal opening value, repeat the aforementioned steps.

[0020] Furthermore, set the APU power hold time t1 and the APU shutdown hold time t2; when the APU is turned on and P APU When P1 is equal to P1, it can only be changed to P when time t>t1. APU =P2 or shut down the APU; once the APU is shut down, it can only be turned on again when time t>t2.

[0021] Furthermore, t1 = 90s and t2 = 60s.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention controls the start-up of the range extender and the allocation of the required power according to the remaining battery charge (SOC) and the vehicle operating conditions. While ensuring the vehicle's power performance, it can effectively reduce the discharge power of the power battery. Moreover, using the remaining battery charge (SOC) as a condition for allocating the required power can effectively ensure the safety of the power battery. Attached Figure Description

[0023] Figure 1 This is a flowchart illustrating the process of determining whether the range extender APU is enabled in this invention.

[0024] Figure 2 This is a flowchart illustrating the range extender power allocation process based on the battery's remaining SOC and the vehicle's operating conditions in this invention.

[0025] Figure 3 This is a flowchart illustrating how the range extender changes its operating conditions in this invention. Detailed Implementation

[0026] This embodiment proposes a control method for a range-extended electric vehicle, firstly as follows: Figure 1 The flowchart shown illustrates the process of determining whether the range extender is activated. This process is used by the vehicle controller to determine whether the range extender APU (Automatic Power Unit) is activated. The specific control methods include:

[0027] S010, The vehicle controller receives the status of the range extender APU (whether it is faulty). If the APU is fault-free, proceed to the next step.

[0028] S020, the vehicle controller determines the high voltage status (READY or NO READY). If the vehicle status is READY, proceed to the next step.

[0029] S030, the vehicle controller receives the remaining battery charge (SOC) and the current vehicle speed. When the battery charge (SOC) is less than the preset calibration value x=70% and the vehicle speed is greater than the calibration value v=20km / h, or when the battery charge (SOC) is less than the preset calibration value z=20% and the vehicle speed is not equal to zero, the next step is executed.

[0030] S100, control the range extender APU to start according to the above steps.

[0031] In S100, the vehicle controller uses the power MAP table corresponding to vehicle speed / throttle opening / SOC to look up Pspd, Pacc, and Psoc, as shown in Table 1, specifically including:

[0032] 1) Select the power point P that has the lowest fuel consumption rate near 40%, 60%, 80%, and 100% of the range extender's rated power. A P B P C P D This serves as the operating point for the range extender APU.

[0033] 2) Based on the vehicle speed and the power point in step 1), set the vehicle speed-power MAP table. Pspd can be obtained by looking up the table based on the current vehicle speed.

[0034] 3) Based on the accelerator pedal opening and the power point in step 1), set the accelerator opening-power MAP table. Pacc can be obtained by looking up the table based on the current accelerator pedal opening.

[0035] 4) Based on the remaining battery SOC and the power point setting in step 1), the Psoc can be obtained by looking up the table according to the current SOC.

[0036]

[0037] Table 1: Power Map Table Corresponding to Vehicle Speed / Throttle Opening / SOC

[0038] Figure 2 This embodiment presents a flowchart of range extender power allocation based on battery remaining SOC and vehicle operating conditions, used by the vehicle controller to determine the operating power of the range extender APU. The control method specifically includes:

[0039] S110, when the battery SOC is not lower than the preset calibration value x=70%, P APU =0;

[0040] S120, when the battery charge SOC is lower than the preset calibration value x=70% but not lower than the preset calibration value y=30%, the vehicle controller VCU sends a power request P to the range extender APU. APU =min{ P spd P acc};

[0041] S130, when the battery SOC is lower than the preset calibration value y=30%, the APU power is set to...

[0042] PAPU =max{ P acc P SOC};

[0043] S140, repeat steps S110, S120, and S130.

[0044] Figure 3 This is a flowchart illustrating how a range extender changes its operating conditions, as described in this embodiment. The flowchart is used by the vehicle controller to determine the operating power of the range extender APU. The control method specifically includes:

[0045] To protect the engine in the range extender and avoid frequent engine start-stop and operating condition changes, the APU power hold time t1=90s and the APU shutdown hold time t2=60s are set.

[0046] 1) When the APU is enabled and P APU When P = P1, P can only be changed when time t > t1. APU =P2 or shut down APU;

[0047] 2) Once the APU is shut down, it can only be restarted when time t > t2.

[0048] This embodiment can control the range extender to start and allocate the required power according to the battery's remaining SOC and the vehicle's operating conditions. While ensuring the vehicle's power performance, it can effectively reduce the power battery's discharge power. Moreover, using the battery's remaining SOC as a condition for allocating the required power can effectively ensure the safety of the power battery.

[0049] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the specific embodiments described above, and various changes and modifications can be made to the present invention, all of which fall within the scope of the claims.

Claims

1. A control method for a range-extended electric vehicle, characterized in that: The vehicle controller allocates the required power to the range-extended electric vehicle based on the remaining battery charge (SOC) and operating conditions, including the following specific steps: Step 1: Receive the status of the range extender APU through the vehicle controller to determine if there is a fault. If there is a fault, the range extender APU is prohibited from starting and the fault is detected. If the APU is not faulty, continue to the next step. If the range extender APU is faulty, control the vehicle to drive in pure electric mode and prohibit the start of the range extender APU. Step 2: The vehicle controller determines whether the vehicle's high-voltage status is READY or NO READY. If the vehicle status is READY, the next step is executed. Step 3: The vehicle controller receives the remaining battery charge (SOC) and the current vehicle speed. When the battery charge (SOC) is less than the preset calibration value x=70% and the vehicle speed is greater than the calibration value v=20km / h, or when the battery charge (SOC) is less than the preset calibration value z=20% and the vehicle speed is not equal to zero, the next step is executed. By setting the corresponding parameters in the MAP table and obtaining the corresponding data through table lookup, the specific steps include: Step 3.1: Within the rated power range of the range extender, select power points P near 40%, 60%, 80%, and 100% of the rated power of the range extender where the fuel consumption rate is relatively low. A P B P C P D As the operating point of the range extender APU; Step 3.2: Based on the vehicle speed and the power point in Step 3.1, set the vehicle speed-power MAP table. Pspd can be obtained by looking up the table based on the current vehicle speed. Step 3.3: Set the throttle opening-MAP table according to the throttle pedal opening and the power point in Step 3.1, and obtain Pacc by looking up the table through the vehicle controller according to the current throttle pedal opening; Step 3.4: Based on the remaining battery SOC and the power point setting SOC-power MAP table in step 3.1, the Psoc can be obtained by looking up the table based on the current SOC. Step 4: Based on the range extender APU status, vehicle high voltage status, remaining battery SOC, and current vehicle speed from the above steps, decide whether to activate the range extender APU. Step 5: After the range extender APU is activated, the power distribution control method for the range-extended vehicle is executed. Based on the remaining battery charge (SOC) obtained in the previous steps and the vehicle's operating conditions, the required power is allocated. When the battery SOC is less than a preset calibration value x but not less than a preset calibration value y, the vehicle controller VCU sends a power request P to the range extender APU. APU =min{ P spd P acc When the battery SOC is less than the preset calibration y, the APU power is set to P. APU =max{ P acc P SOC }; Set the APU power hold time t1 and the APU shutdown hold time t2; When the APU is turned on and P APU When P1 is equal to P1, it can only be changed to P when time t>t1. APU =P2 or shut down the APU; after the APU is shut down, it can be turned on again when time t>t2; repeat the above steps according to the vehicle's latest SOC, vehicle speed and accelerator pedal opening value.

2. The control method for a range-extended electric vehicle according to claim 1, characterized in that: In step 5, the current vehicle speed, current accelerator pedal travel, and remaining battery charge (SOC) are received through the vehicle controller; the required power value is allocated based on the remaining battery charge (SOC), the current vehicle speed, and the accelerator pedal travel.

3. The control method for a range-extended electric vehicle according to claim 1, characterized in that: The values ​​are t1=90s and t2=60s.

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