Range extender control method and device, and four-wheel drive range extender vehicle

Abstract

The application relates to the technical field of new energy vehicles, and provides a range extender control method and device and a four-wheel drive range extender vehicle. The method comprises the following steps: if it is determined that the power driving mode of the four-wheel drive range extender vehicle is a four-wheel driving mode, then the power generation power request value is split into first and second power generation power request values based on real-time vehicle speed; a first control instruction is issued to a first range extender controller, so that the first range extender controller controls the first range extender based on the first power generation power request value to indirectly regulate the torque and rotating speed of a front axle motor; and a second control instruction is issued to a second range extender, so that the second range extender controller controls the second range extender based on the second power generation power request value to indirectly regulate the torque and rotating speed of a rear axle motor. According to the application, the power battery is omitted, the energy utilization rate is greatly improved, the rotating speed and torque of the front axle motor and the rear axle motor can be indirectly regulated through the first and second range extender controllers, and the comprehensive performance of the range extender is improved.

Description

Technical Field

[0001] This application relates to the field of new energy vehicles, and in particular to a range extender control method, device and four-wheel drive range extender vehicle. Background Technology

[0002] Compared to two-wheel-drive vehicles, four-wheel-drive vehicles have greater potential for interaction between their wheels and the ground, making them less prone to losing full traction. This results in significant advantages in traction and driving stability on surfaces with poor traction, as well as superior off-road capability on rough terrain. In recent years, to address the short driving range of traditional electric vehicles, the focus of electric vehicle development has gradually shifted to range-extended electric vehicles (REEVs). REEVs with four-wheel-drive capability (hereinafter referred to as "four-wheel-drive REEVs") combine the advantages of four-wheel drive and a longer driving range, making them a popular research topic in the field of new energy vehicles.

[0003] In current four-wheel drive range-extended vehicle range-extender systems, the energy transfer process from the range extender's generator to the electric motor requires simultaneous charging and discharging of the power battery. This charging and discharging process results in significant energy loss (approximately 10%). Furthermore, existing range extender control schemes in four-wheel drive range-extender systems still suffer from unreasonable power generation allocation, leading to insignificant optimization of the range extender's overall performance. Summary of the Invention

[0004] In view of this, the present application provides a range extender control method, device and four-wheel drive range extender vehicle to solve the problems that the existing four-wheel drive range extender vehicle range extender system has large power loss and the range extender control scheme still has unreasonable power generation distribution, resulting in an insignificant optimization effect on the overall performance of the range extender.

[0005] A first aspect of this application provides a range extender control method applied to a four-wheel drive range extender vehicle. The four-wheel drive range extender vehicle includes a vehicle controller, a first range extender controller and a second range extender controller respectively communicateably connected to the vehicle controller; a first range extender communicately connected to the first range extender controller, a front axle motor electrically connected to the first range extender controller; a second range extender communicately connected to the second range extender controller, and a rear axle motor electrically connected to the second range extender controller.

[0006] Range extender control methods, applied to vehicle controllers, include:

[0007] Obtain the power generation request value for the four-wheel drive range-extended vehicle at the current moment;

[0008] If the power drive mode of the four-wheel drive range-extended vehicle is determined to be four-wheel drive mode, the real-time vehicle speed of the four-wheel drive range-extended vehicle at the current moment is collected, and the power generation request value is split into a first power generation request value and a second power generation request value based on the real-time vehicle speed.

[0009] A first control command is sent to the first range extender controller to enable the first range extender controller to execute the first control command and control the first range extender based on the first power generation request value to indirectly regulate the torque and speed of the front axle motor;

[0010] A second control command is issued to the second range extender so that the second range extender controller executes the second control command and controls the second range extender based on the second power generation request value to indirectly regulate the torque and speed of the rear axle motor.

[0011] A second aspect of this application provides a range extender control device, comprising:

[0012] The acquisition module is configured to acquire the power generation request value for the four-wheel drive range-extended vehicle at the current moment;

[0013] The splitting module is configured to, if it is determined that the power drive mode of the four-wheel drive range-extended vehicle is four-wheel drive mode, collect the real-time vehicle speed of the four-wheel drive range-extended vehicle at the current moment, and split the power generation request value into a first power generation request value and a second power generation request value based on the real-time vehicle speed.

[0014] The first sending module is configured to send a first control command to the first range extender controller, so that the first range extender controller executes the first control command and controls the first range extender based on the first power generation request value to indirectly regulate the torque and speed of the front axle motor.

[0015] The second sending module is configured to send a second control command to the second range extender, so that the second range extender controller executes the second control command and controls the second range extender based on the second power generation request value to indirectly regulate the torque and speed of the rear axle motor.

[0016] A third aspect of the embodiments of this application provides a four-wheel drive range-extended vehicle, including a vehicle controller;

[0017] A first range extender controller and a second range extender controller, which are respectively connected to the vehicle controller for communication.

[0018] A first range extender that is communicatively connected to a first range extender controller, and a front axle motor that is electrically connected to the first range extender;

[0019] A second range extender that is communicatively connected to a second range extender controller, and a rear axle motor that is electrically connected to the second range extender;

[0020] The vehicle controller includes the range extender control unit in the second aspect.

[0021] A fourth aspect of this application provides a readable storage medium storing a computer program that, when executed by a processor, implements the steps of the above-described method.

[0022] Compared with the prior art, the beneficial effects of the embodiments of this application include at least the following: On the one hand, the power system of the four-wheel drive range-extended vehicle in the embodiments of this application includes a vehicle controller, a first range extender controller and a second range extender controller respectively communicatively connected to the vehicle controller; a first range extender communicatively connected to the first range extender controller, and a front axle motor electrically connected to the first range extender controller; a second range extender communicatively connected to the second range extender controller, and a rear axle motor electrically connected to the second range extender controller. Compared with the power system of a traditional four-wheel drive range-extended vehicle, the power system of the four-wheel drive range-extended vehicle in the embodiments of this application omits the power battery that powers the front axle motor through the power generated by the first range extender, and the power battery that powers the rear axle motor through the power generated by the second range extender. This avoids the large energy loss (approximately 10%) caused by the power battery during charging and discharging, which is beneficial to improving energy utilization and reducing the weight of the entire vehicle. On the other hand, the range extender control method proposed in this application is applied to the above-mentioned vehicle controller. This method determines the power generation ratio allocated to the first range extender and the second range extender based on the real-time vehicle speed of the four-wheel drive range extender, making the power generation allocation more reasonable. Then, by issuing control commands to the first range extender controller and the second range extender controller respectively, they execute the corresponding control commands and control the speed and torque of their corresponding range extenders according to the power generation request value allocated to them, thereby indirectly regulating the speed and torque of the front axle motor and the rear axle motor, which can significantly improve the overall performance of the range extender. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of a four-wheel drive range-extended vehicle provided in an embodiment of this application;

[0025] Figure 2 This is a schematic flowchart of a range extender control method provided in an embodiment of this application;

[0026] Figure 3 This is a schematic diagram of the structure of a range extender control device provided in an embodiment of this application;

[0027] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0028] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0029] The following detailed description, in conjunction with the accompanying drawings, describes a range extender control method, apparatus, and four-wheel drive range extender vehicle according to embodiments of this application.

[0030] Figure 1 This is a schematic diagram of the structure of a four-wheel drive range-extended vehicle according to an embodiment of this application. For ease of description, only the parts of the structure related to the embodiment of this application are shown in the figure, which are described in detail below:

[0031] like Figure 1 As shown, the power system of the four-wheel drive range-extended vehicle includes a vehicle controller 101, a first range extender controller 102 and a second range extender controller 103 which are respectively communicatively connected to the vehicle controller 101; a first range extender 104 which is communicatively connected to the first range extender controller 102; a front axle motor 105 which is electrically connected to the first range extender 104; a second range extender 106 which is communicatively connected to the second range extender controller 103; and a rear axle motor 107 which is electrically connected to the second range extender 106.

[0032] The first range extender 104 includes a first engine and a first generator (not shown in the figure). The first engine and the first generator are mechanically connected, and the first motor and the front axle motor are electrically connected. The second range extender 106 includes a second engine and a second generator (not shown in the figure). The second engine and the second generator are mechanically connected, and the second generator and the rear axle motor are electrically connected.

[0033] The Vehicle Control Unit (VCU) 101, also known as the powertrain controller, is the core component of the entire four-wheel drive range-extended vehicle.

[0034] Both the first range extender controller 102 and the second range extender controller 103 can be ECUs (Electronic Control Units).

[0035] Mechanical connection refers to connecting two or more components through the mechanical interlocking of connecting parts. Specifically, the first engine and the first generator are connected by a mechanical connection, which can be achieved by connecting the first engine and the first generator through connecting parts such as bearings and couplings.

[0036] In a broad sense, electrical connection refers to the collection of all electrical circuits in an electrical product, including power connection components such as power plugs, power terminals, power cords, internal wires, and internal connecting parts. In a narrow sense, it refers to all ways in which different conductors are connected within a product. Specifically, the first motor and the front axle motor are connected by an electrical connection, which can be achieved by connecting the conductors in the first motor and the front axle motor with wires.

[0037] The vehicle controller 101 can communicate with the first range extender controller 102 and the second range extender controller 103 via a CAN bus or an Ethernet bus.

[0038] Compared with the power system of traditional four-wheel drive range-extended vehicles, the power system of the four-wheel drive range-extended vehicle (generator direct drive four-wheel drive range-extended vehicle) provided in this application embodiment omits the power battery that powers the front axle motor with the power generated by the first range extender, and the power battery that powers the rear axle motor with the power generated by the second range extender. This can avoid the large energy loss (about 10%) caused by the power battery during charging and discharging, which is conducive to improving energy utilization and reducing the weight of the whole vehicle.

[0039] Figure 2 This is a flowchart illustrating a range extender control method provided in an embodiment of this application. Figure 2 The range extender control method can be derived from Figure 1 The vehicle controller 101 performs the execution. For example... Figure 2 As shown, the range extender control method may specifically include the following steps:

[0040] Step S201: Obtain the power generation request value for the four-wheel drive range-extended vehicle at the current moment;

[0041] Step S202: If it is determined that the power drive mode of the four-wheel drive range-extended vehicle is four-wheel drive mode, then the real-time vehicle speed of the four-wheel drive range-extended vehicle at the current moment is collected, and the power generation request value is split into a first power generation request value and a second power generation request value based on the real-time vehicle speed.

[0042] Step S203: Send a first control command to the first range extender controller so that the first range extender controller executes the first control command and controls the first range extender based on the first power generation request value to indirectly regulate the torque and speed of the front axle motor.

[0043] Step S204: A second control command is sent to the second range extender so that the second range extender controller executes the second control command and controls the second range extender based on the second power generation request value to indirectly regulate the torque and speed of the rear axle motor.

[0044] As an example, the vehicle controller 101 can collect relevant parameters for calculating the power generation request value through various sensor information acquisition devices mounted on the four-wheel drive range-extended vehicle. These relevant parameters mainly include the real-time vehicle speed signal and accelerator pedal opening signal of the four-wheel drive range-extended vehicle at the current moment. Then, the collected relevant parameters are input into a pre-trained power generation calculation model for processing to obtain the total power generation request value of the first and second range extenders of the four-wheel drive range-extended vehicle at the current moment. The power generation calculation model can be a neural network model (such as a convolutional neural network model) pre-trained using existing machine learning methods.

[0045] The technical solution provided in this application determines the power generation ratio allocated to the first and second range extenders based on the real-time vehicle speed of the four-wheel drive range-extended vehicle, making the power generation allocation more reasonable. The vehicle controller issues control commands to the first and second range extenders based on the first and second power generation request values, respectively, so that they execute the corresponding control commands and control the speed and torque of their respective range extenders according to the power generation request values ​​allocated to them. This can indirectly regulate the speed and torque of the front axle motor and the rear axle motor, thereby improving the overall performance of the first and second range extenders of the four-wheel drive range-extended vehicle.

[0046] In some embodiments, the vehicle controller 101 splits the power generation request value into a first power generation request value and a second power generation request value based on the real-time vehicle speed, specifically including:

[0047] When the real-time vehicle speed is less than the first vehicle speed, the power generation request value will be determined as the second power generation request value.

[0048] When the real-time vehicle speed is greater than or equal to the first vehicle speed and less than the second vehicle speed, the power generation request value is split into the first power generation request value and the second power generation request value, wherein the first vehicle speed is less than the second vehicle speed;

[0049] When the real-time vehicle speed is greater than or equal to the second vehicle speed, the power generation request value is split into the first power generation request value and the second power generation request value.

[0050] Vehicle speed is a key control parameter that determines the overall vehicle economy. Vehicle speed is closely related to the vehicle's operating mode. The rationality of torque distribution between different power sources under different vehicle operating modes will affect the energy utilization rate.

[0051] In the first scenario, when the real-time vehicle speed V act Less than the first vehicle speed V fir At a initial speed of 10 km / h, the vehicle is in a starting condition, and rear-wheel drive mode is preferred, meaning the rear axle motor outputs 100% torque. At this time, the power generation request value P0 (vehicle power generation request) can be set as the second power generation request value P2. This helps improve the vehicle's fuel economy.

[0052] In the second scenario, when the real-time vehicle speed V act Greater than or equal to the first vehicle speed V fir (For example, the first speed is 10 km / h) and less than the second speed V sec (For example, the second speed is 70 km / h), that is, V fir ≤V act <V sec Furthermore, when the vehicle is operating at a constant speed, the requested power generation value P0 can be split into a first requested power generation value P1 and a second requested power generation value P2 in a 3:2 ratio, i.e., P1 = 0.6 * P0 and P2 = 0.4 * P0. In this way, it can be ensured that the second range extender can reserve enough energy to supply the rear axle motor to meet the vehicle's possible acceleration conditions.

[0053] The third scenario is when the real-time vehicle speed V act Greater than or equal to the first vehicle speed V fir (For example, the first speed is 10 km / h) and less than the second speed V sec (For example, the second speed is 70 km / h), that is, V fir ≤V act <V sec Furthermore, when the vehicle is accelerating, based on the second scenario, the proportion of the second power generation request value P2 can be gradually increased according to a preset upward adjustment gradient, while simultaneously decreasing the proportion of the first power generation request value P1. For example, if the preset upward adjustment gradient is 0.1, then the proportion of the second power generation request value P2 will be increased sequentially to 0.4→0.5→0.6→0.7→0.8→0.9→1.0, while simultaneously decreasing the proportion of the first power generation request value P1 sequentially to 0.6→0.5→0.4→0.3→0.2→0.1→0. This ensures the timely delivery of vehicle torque, providing passengers with a better acceleration experience.

[0054] The fourth scenario is when the real-time vehicle speed V act Greater than or equal to the second vehicle speed V sec(For example, if the second vehicle speed is 70 km / h) and the vehicle is operating at a constant speed, based on the second scenario, the proportion of the first power generation request value P1 can be gradually increased according to a preset upward adjustment gradient until the proportion of the first power generation request value P1 reaches 1, while simultaneously decreasing the proportion of the second power generation request value P2 to 0. For instance, if the preset upward adjustment gradient is 0.1, then the proportion of the first power generation request value P1 will be increased sequentially to 0.6 → 0.7 → 0.8 → 0.9 → 1.0, while simultaneously decreasing the proportion of the second power generation request value P2 sequentially to 0.4 → 0.3 → 0.2 → 0.1 → 0. This ensures the stability of the vehicle's operation.

[0055] The fifth scenario is when the real-time vehicle speed V act Greater than or equal to the second vehicle speed V sec (For example, when the second vehicle speed is 70 km / h) and the vehicle is accelerating, the proportions of the first power generation request value P1 and the second power generation request value P2 are each 0.5 of the power generation request value P0. That is, the power generation request value P0 is broken down into...

[0056] In this embodiment, the vehicle's real-time speed is acquired, and the current power drive mode is determined based on this speed. Then, based on the vehicle's power drive mode, the vehicle's (whole vehicle) power generation request value is reasonably divided. After that, according to the division result, a first control command is sent to the first range extender controller and / or a second control command is sent to the second range extender controller. This allows the first range extender controller to control the first range extender according to the received first control command, thereby indirectly regulating the torque and speed of the front axle motor. And / or, the second range extender controller can control the second range extender according to the received second control command, thereby indirectly regulating the torque and speed of the rear axle motor. This improves the overall performance of the first and second range extenders in the four-wheel drive range-extended vehicle, while also improving the overall vehicle's economic performance.

[0057] In some embodiments, please refer to Figure 1 and Figure 2When the first range extender controller 102 receives the first control command issued by the vehicle controller 101, it controls the first range extender 104 based on the first power generation request value to indirectly regulate the torque and speed of the front axle motor 105. Specifically, the first range extender controller 102 can first perform power correction on the first power generation request value to obtain a first target power generation value; then, based on the first target power generation value, determine the first target speed and first target torque of the first range extender 104; finally, dynamically adjust the first actual speed of the first range extender 104 at the current moment to the first target speed to indirectly regulate the speed of the front axle motor 105, and dynamically adjust the first actual torque of the first range extender 104 at the current moment to the first target torque to indirectly regulate the torque of the front axle motor 105.

[0058] In some embodiments, the first power generation request value is modified to obtain a first target power generation value, specifically including:

[0059] Obtain the operating status information, fault status information, engine coolant temperature, and generator temperature of the first range extender 104;

[0060] The first power generation limit of the first range extender 104 is determined based on the working status information, the second power generation limit of the first range extender 104 is determined based on the fault status information, the third power generation limit of the first range extender 104 is determined based on the engine coolant temperature, and the fourth power generation limit of the first range extender 104 is determined based on the generator temperature.

[0061] The first target power generation value is determined based on the first power generation limit, the second power generation limit, the third power generation limit, the fourth power generation limit, and the first power generation request value.

[0062] Operating status information, including the power-on, power-off, low-voltage standby, high-voltage standby, and power generation status of the first range extender 104.

[0063] The fault status information is used to characterize whether the first range extender 104 is in a shutdown fault state.

[0064] In this embodiment of the first range extender 104, the first engine employs water cooling, with the optimal operating range for the engine coolant temperature being 70–90°C. If the engine coolant temperature is below 70°C or above 90°C, the lubrication performance, power performance, fuel consumption, and emissions of the first engine will all be affected, and prolonged exposure may even shorten its service life. Therefore, when the first range extender 104 is operating, reasonably limiting its power generation based on the engine's coolant temperature can protect the first engine and extend its service life.

[0065] If the temperature of the first generator exceeds 140℃, its power generation efficiency will decrease significantly, and prolonged exposure to this temperature can shorten its service life. Therefore, when the first range extender 104 is operating, reasonably limiting its power generation based on the temperature of the first generator can protect the first generator and extend its service life.

[0066] In some implementations, the first power generation limit P of the first range extender is determined based on the operating status information. limit1 Specifically, when the first range extender 104 is in power-on, power-off, low-voltage standby, or high-voltage standby state, the first power generation limit P limit1 The first power output limit P is 0 kW; when the first range extender 104 is in power generation mode. limit1 This is the maximum permissible power generation value of the first range extender 104. For example, if the maximum permissible power generation of the first range extender 104 is y kilowatts, then when the first range extender 104 is in power generation mode, the first power generation limit is y kilowatts.

[0067] In some implementations, the second power generation limit P of the first range extender is determined based on fault status information. limit2 Specifically, when the first range extender 104 is in a shutdown fault state, the second power generation limit is 0 kilowatts.

[0068] In some implementations, the third power generation limit P of the first range extender is determined based on the engine coolant temperature. limit3 Specifically, the process involves: first, determining a first correction coefficient based on the engine coolant temperature of the first engine; then, calculating a third power generation limit P based on the first correction coefficient, the maximum allowable power generation of the first range extender 104, and the minimum allowable power generation. limit3 The first correction factor is related to the engine coolant temperature T. eng The correspondence is shown in Table 1 below:

[0069] Table 1. First correction factor and engine coolant temperature T eng Correspondence table

[0070] <![CDATA[-30℃≤T eng <0℃]]> <![CDATA[α1]]> <![CDATA[0℃≤T eng <20℃]]> <![CDATA[α2]]> <![CDATA[20℃≤T eng <40℃]]> <![CDATA[α3]]> <![CDATA[40℃≤T eng <70℃]]> <![CDATA[α4]]> <![CDATA[70℃≤T eng <90℃]]> <![CDATA[α5]]> <![CDATA[90℃≤T eng <110℃]]> <![CDATA[α6]]>

[0071] After determining the first correction factor α based on Table 1 above, the third power generation limit P can be calculated according to the following formula (1). limit3 .

[0072] P limit3 =α(P max +P min )+P min (1);

[0073] In equation (1), α represents the first correction coefficient, and P limit3 P represents the third power generation limit. max P represents the maximum permissible power generation of the first range extender. min This indicates the minimum permissible power generation of the first range extender.

[0074] In some implementations, the fourth power generation limit of the first range extender is determined based on the generator temperature. Specifically, a second correction coefficient β is first determined based on the temperature of the first generator, and then the fourth power generation limit P is calculated based on the second correction coefficient, the maximum allowable power generation of the first range extender 104, and the minimum allowable power generation. limit4 The second correction factor is related to the generator temperature T. elect The correspondence is shown in Table 2 below:

[0075] Table 2 Second Correction Factor and Generator Temperature T elect Correspondence table

[0076] <![CDATA[140℃≤T elect <145℃]]> <![CDATA[β1]]> <![CDATA[145℃≤T eng <150℃]]> <![CDATA[β2]]> <![CDATA[150℃≤T eng <155℃]]> <![CDATA[β3]]> <![CDATA[155℃≤T eng <160℃]]> <![CDATA[β4]]>

[0077] After determining the second correction factor β based on Table 2 above, the fourth power generation limit P can be calculated according to the following formula (2). limit4 .

[0078] P limit4 =β(P max +P min )+P min (2);

[0079] In equation (1), β represents the second correction coefficient, and P limit4 P represents the fourth power generation limit. max P represents the maximum permissible power generation of the first range extender. min This indicates the minimum permissible power generation of the first range extender.

[0080] Next, the first target power generation value P is determined according to the following formula (3). tar .

[0081]

[0082] In equation (3), P1 represents the first requested power generation value, P min P represents the minimum permissible power generation of the first range extender. max P represents the maximum permissible power generation of the first range extender. tar P represents the first target power generation value. limit1 P represents the first power generation limit. limit2 P represents the second power generation limit. limit3P represents the third power generation limit. limit4 This indicates the fourth power generation limit.

[0083] The technical solution provided in this application comprehensively considers the limitations of the first range extender's working state, fault state, engine coolant temperature, and generator temperature on power generation, and combines the first range extender's maximum and minimum allowable power generation to determine the first target power generation value. This not only improves the vehicle's fuel economy but also effectively prevents power conflicts that could lead to malfunctions or damage to the first range extender, thus optimizing the overall performance of the first range extender.

[0084] Similarly, the second target power generation value corresponding to the second range extender 106 can be determined by referring to the method for determining the first target power generation value in the above embodiments, which will not be repeated here.

[0085] In some embodiments, determining a first target speed and a first target torque of the first range extender based on a first target power generation value includes:

[0086] The feedforward mechanical power of the first range extender is determined based on the power generation efficiency of the first range extender and the first target power generation value.

[0087] Calculate the power difference between the first actual power generation value and the first target power generation value of the first range extender at the current moment;

[0088] Calculate the feedback power of the first range extender based on the power difference and the first actual power generation value;

[0089] Based on the feedforward mechanical power and the feedback power generation, the first target speed and the first target torque of the first range extender are determined.

[0090] Feedforward mechanical power is "advanced compensation" before the first target power generation of the first range extender changes.

[0091] Feedback power generation is the value calculated by the PI control algorithm based on the deviation between the first actual power generation value and the first target power generation value of the first range extender, which enables the power generation of the first range extender to meet the expected target.

[0092] As an example, firstly, the feedforward mechanical power P of the first range extender can be calculated according to formula (4). eng .

[0093]

[0094] In equation (4), P eng P represents the engine's required mechanical power for the first range extender. tarη represents the first target power generation value of the first range extender, and η represents the power generation efficiency of the first range extender.

[0095] Then, the power difference between the first actual power generation value and the first target power generation value of the first range extender can be calculated according to formula (5).

[0096] P diff =P tar- P real (5);

[0097] In equation (5), P diff P represents the power difference between the first actual power output value and the first target power output value of the first range extender. real P represents the first actual power output value of the first range extender. tar This indicates the first target power generation value of the first range extender.

[0098] Next, a PID control algorithm is used, based on the power difference P. diff The first actual power generation value P real Calculate the feedback power generation p of the first range extender feed The ideal equation for the PID control algorithm is shown in equation (6).

[0099]

[0100] In equation (6), u(t) represents the first actual power generation value P of the first range extender. real ;K p K i K d These represent the proportional gain, integral time constant, and derivative time constant of the PID controller, respectively, where t is the time constant; e(t) is the power difference P. diff The initial value is 0.

[0101] Since continuous PID control algorithm cannot be used in actual control process, the above formula (6) is simplified to formula (7) by discretizing and taking the increment. The feedback power generation P of the first range extender is calculated according to formula (7). feed .

[0102] Vu(k)=u(k)-u(k-1)=δe(k)+ωe(k-1) (7);

[0103] In equation (7), Vu(k) represents the feedback power generation p of the first range extender. feed ,coefficient Coefficient ω=-K pT is the sampling period, e(k) represents the power difference between the first actual power generation value and the first target power generation value of the first range extender at the kth sampling time, and e(k-1) represents the power difference between the first actual power generation value and the first target power generation value of the first range extender at the (k-1)th sampling time.

[0104] P M =P feed +P eng (8);

[0105] In equation (8), P M P represents the first target mechanical power of the first range extender, that is, the mechanical power output of the engine required to generate the first target power; feed P represents the feedback power generation of the first range extender. eng This represents the feedforward mechanical power of the first range extender.

[0106] Since the first engine and the first generator of the first range extender are connected by a mechanical connection, the first target mechanical power is the mechanical power output of the first engine required for the first target power generation of the first range extender.

[0107] In some embodiments, determining a first target speed and a first target torque of the first range extender based on feedforward mechanical power and feedback power generation includes:

[0108] The torque compensation value of the first range extender is determined based on the first actual power generation value and the first target power generation value.

[0109] Determine the first target mechanical power based on the feedforward mechanical power and the feedback power, and find the required power generation speed and required power generation torque corresponding to the first target mechanical power.

[0110] The required power generation speed is determined as the first target speed;

[0111] The first target torque is determined based on the torque compensation value and the required power generation torque.

[0112] As an example, firstly, the difference between the first actual power generation value and the first target power generation value of the first range extender can be calculated. Then, the torque compensation value of the first range extender is calculated using a PI controller. After calculating the first target mechanical power, the required power generation speed and required torque corresponding to the first target mechanical power can be obtained by consulting a table of correspondence between "first target mechanical power - required power generation speed - required power generation torque". This table can be used to determine the required power generation speed and required torque values ​​corresponding to the first target mechanical power, with constraints such as fuel economy, power performance, noise, and emissions. Then, each set of first target mechanical power values ​​and their corresponding required power generation speeds and torques are organized into a table of correspondence between "first target mechanical power - required power generation speed - required power generation torque". The required power generation speed obtained from the query is determined as the first target speed of the first generator of the first range extender. The calculated torque compensation value and the obtained required power generation torque are added together to obtain the first target torque of the first engine of the first range extender.

[0113] Similarly, the second target speed and second target torque corresponding to the second range extender 106 can be determined by referring to the determination method of the first target speed and the first target torque in the above embodiments, which will not be repeated here.

[0114] The above method enables rapid tracking of the mechanical power of the first range extender and precise control of its power generation. It also accelerates the response of the first range extender to engine torque while keeping the generator speed step value constant, thus effectively suppressing the power reverse overshoot problem that exists in the first range extender during actual operation.

[0115] In some embodiments, dynamically adjusting the first actual speed of the first range extender at the current moment to a first target speed to indirectly control the speed of the front axle motor includes:

[0116] Obtain the actual front axle motor speed and the target front axle motor speed;

[0117] Calculate the speed difference between the actual front axle motor speed and the target front axle motor speed;

[0118] Based on the speed difference, determine the speed adjustment gradient to dynamically adjust the first actual speed to the first target speed;

[0119] According to the speed adjustment gradient, the first actual speed of the first range extender is dynamically adjusted to the first target speed, thereby indirectly controlling the speed of the front axle motor.

[0120] Specifically, the speed difference between the actual front axle motor speed and the target front axle motor speed can be calculated according to formula (9).

[0121] R diff =R M -R real (9);

[0122] In equation (9), R diff R represents the speed difference between the actual front axle motor speed and the target front axle motor speed. M R represents the target front axle motor speed. real This indicates the actual front axle motor speed.

[0123] If R diff >0, meaning the target front axle motor speed is greater than the actual front axle motor speed, then the actual front axle motor speed needs to be gradually increased to reach the target front axle motor speed. If R diff If the target front axle motor speed is less than the actual front axle motor speed, then the actual front axle motor speed needs to be gradually reduced to the target front axle motor speed.

[0124] In practical applications, if R diff If R > 0, then the actual front axle motor speed will gradually increase to the target front axle motor speed according to the preset speed increase gradient. diff If the value is less than 0, the actual front axle motor speed will be gradually reduced to the target front axle motor speed according to the preset speed adjustment gradient.

[0125] In this way, the first actual speed of the first range extender can be dynamically and smoothly adjusted to the first target speed, while the speed of the front axle motor can be indirectly controlled.

[0126] Similarly, the second actual speed of the second range extender can be dynamically and smoothly adjusted to the second target speed by referring to the above implementation method, while the speed of the rear axle motor can be indirectly controlled.

[0127] All of the above-mentioned optional technical solutions can be combined in any way to form the optional embodiments of this application, and will not be described in detail here.

[0128] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0129] Figure 3 This is a schematic diagram of a range extender control device provided in an embodiment of this application. Figure 3 As shown, the range extender control device includes:

[0130] The acquisition module 301 is configured to acquire the power generation request value for the four-wheel drive range-extended vehicle at the current moment;

[0131] The split module 302 is configured to, if it is determined that the power drive mode of the four-wheel drive range-extended vehicle is four-wheel drive mode, collect the real-time vehicle speed of the four-wheel drive range-extended vehicle at the current moment, and split the power generation request value into a first power generation request value and a second power generation request value based on the real-time vehicle speed.

[0132] The first issuing module 303 is configured to issue a first control command to the first range extender controller, so that the first range extender controller executes the first control command and controls the first range extender based on the first power generation request value to indirectly regulate the torque and speed of the front axle motor.

[0133] The second sending module 304 is configured to send a second control command to the second range extender so that the second range extender controller executes the second control command and controls the second range extender based on the second power generation request value to indirectly regulate the torque and speed of the rear axle motor.

[0134] In some embodiments, the splitting module 302 described above includes:

[0135] The power determination unit is configured to determine the power generation request value as the second power generation request value when the real-time vehicle speed is less than the first vehicle speed;

[0136] The first splitting unit is configured to split the power generation request value into a first power generation request value and a second power generation request value when the real-time vehicle speed is greater than or equal to the first vehicle speed and less than the second vehicle speed, wherein the first vehicle speed is less than the second vehicle speed.

[0137] The second splitting unit is configured to split the power generation request value into a first power generation request value and a second power generation request value when the real-time vehicle speed is greater than or equal to the second vehicle speed.

[0138] In some embodiments, the first range extender controller includes a control module configured to control the first range extender based on a first power generation request value to indirectly control the torque and speed of the front axle motor.

[0139] This control module includes:

[0140] The correction unit is configured to perform power correction on the first power generation request value to obtain the first target power generation value;

[0141] The determining unit is configured to determine the first target speed and the first target torque of the first range extender based on the first target power generation value;

[0142] The adjustment unit is configured to dynamically adjust the first actual speed of the first range extender at the current moment to the first target speed, so as to indirectly control the speed of the front axle motor, and to dynamically adjust the first actual torque of the first range extender at the current moment to the first target torque, so as to indirectly control the torque of the front axle motor.

[0143] In some embodiments, the above-described correction unit includes:

[0144] The acquisition component is configured to acquire the operating status information, fault status information, engine coolant temperature, and generator temperature of the first range extender.

[0145] The first determining component is configured to determine a first power generation limit of the first range extender based on operating status information, a second power generation limit of the first range extender based on fault status information, a third power generation limit of the first range extender based on engine coolant temperature, and a fourth power generation limit of the first range extender based on generator temperature.

[0146] The second determining component is configured to determine a first target power generation value based on a first power generation limit, a second power generation limit, a third power generation limit, a fourth power generation limit, and a first power generation request value.

[0147] In some embodiments, the determining unit described above includes:

[0148] The third determining component is configured to determine the feedforward mechanical power of the first range extender based on the power generation efficiency of the first range extender and the first target power generation value;

[0149] The first calculation component is configured to calculate the power difference between the first actual power generation value and the first target power generation value of the first range extender at the current moment;

[0150] The second calculation component is configured to calculate the feedback power of the first range extender based on the power difference and the first actual power generation value.

[0151] The fourth determining component is configured to determine the first target speed and the first target torque of the first range extender based on the feedforward mechanical power and the feedback power generation.

[0152] In some embodiments, the adjustment unit described above includes:

[0153] The speed acquisition component is configured to acquire the actual front axle motor speed and the target front axle motor speed.

[0154] The difference calculation component is configured to calculate the speed difference between the actual front axle motor speed and the target front axle motor speed.

[0155] The gradient determination component is configured to determine the speed adjustment gradient for dynamically adjusting the first actual speed to the first target speed based on the speed difference.

[0156] The adjustment component is configured to dynamically adjust the first actual speed of the first range extender to the first target speed according to the speed adjustment gradient, thereby indirectly controlling the speed of the front axle motor.

[0157] In some embodiments, the fourth determining component described above includes:

[0158] The first determining device is configured to determine the torque compensation value of the first range extender based on the first actual power generation value and the first target power generation value;

[0159] The device is configured to determine a first target mechanical power based on the feedforward mechanical power and the feedback power generation, and to find the required power generation speed and required power generation torque corresponding to the first target mechanical power.

[0160] The second determining device is configured to determine the required power generation speed as the first target speed;

[0161] The third determining device is configured to determine the first target torque based on the torque compensation value and the required generated torque.

[0162] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0163] Figure 4 This is a schematic diagram of the electronic device 4 provided in an embodiment of this application. Figure 4 As shown, the electronic device 4 of this embodiment includes: a processor 401, a memory 402, and a computer program 403 stored in the memory 402 and executable on the processor 401. When the processor 401 executes the computer program 403, it implements the steps in the various method embodiments described above. Alternatively, when the processor 401 executes the computer program 403, it implements the functions of each module / unit in the various device embodiments described above.

[0164] Electronic device 4 can be a desktop computer, laptop, handheld computer, cloud server, or other electronic device. Electronic device 4 may include, but is not limited to, processor 401 and memory 402. Those skilled in the art will understand that... Figure 4 This is merely an example of electronic device 4 and does not constitute a limitation on electronic device 4. It may include more or fewer components than shown, or different components.

[0165] The processor 401 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0166] The memory 402 can be an internal storage unit of the electronic device 4, such as a hard disk or RAM of the electronic device 4. The memory 402 can also be an external storage device of the electronic device 4, such as a plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, Flash Card, etc., equipped on the electronic device 4. The memory 402 can also include both internal and external storage units of the electronic device 4. The memory 402 is used to store computer programs and other programs and data required by the electronic device.

[0167] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0168] If integrated modules / units are implemented as software functional units and sold or used as independent products, they can be stored in a readable storage medium (e.g., a computer-readable storage medium). Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program may include computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. A computer-readable storage medium may include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0169] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A range extender control method, characterized in that, The invention is applied to four-wheel drive range-extended vehicles, which include a vehicle controller, a first range extender controller and a second range extender controller respectively communicateably connected to the vehicle controller; a first range extender communicately connected to the first range extender controller, a front axle motor electrically connected to the first range extender controller; a second range extender communicately connected to the second range extender controller, and a rear axle motor electrically connected to the second range extender controller. The range extender control method, applied to the vehicle controller, includes: Obtain the power generation request value for the four-wheel drive range-extended vehicle at the current moment; If it is determined that the power drive mode of the four-wheel drive range-extended vehicle is four-wheel drive mode, then the real-time vehicle speed of the four-wheel drive range-extended vehicle at the current moment is collected, and the power generation request value is split into a first power generation request value and a second power generation request value based on the real-time vehicle speed. A first control command is sent to the first range extender controller to enable the first range extender controller to execute the first control command and control the first range extender based on the first power generation request value to indirectly regulate the torque and speed of the front axle motor. A second control command is issued to the second range extender so that the second range extender controller executes the second control command and controls the second range extender based on the second power generation request value to indirectly regulate the torque and speed of the rear axle motor.

2. The method according to claim 1, characterized in that, Controlling the first range extender based on the first power generation request value to indirectly regulate the torque and speed of the front axle motor includes: The first power generation request value is corrected to obtain the first target power generation value; Based on the first target power generation value, determine the first target speed and the first target torque of the first range extender; The first actual speed of the first range extender at the current moment is dynamically adjusted to the first target speed to indirectly control the speed of the front axle motor. The first actual torque of the first range extender at the current moment is dynamically adjusted to the first target torque to indirectly control the torque of the front axle motor.

3. The method according to claim 2, characterized in that, The first power generation request value is corrected to obtain the first target power generation value, including: Obtain the operating status information, fault status information, engine coolant temperature, and generator temperature of the first range extender; Based on the operating status information, a first power generation limit of the first range extender is determined; based on the fault status information, a second power generation limit of the first range extender is determined; based on the engine coolant temperature, a third power generation limit of the first range extender is determined; and based on the generator temperature, a fourth power generation limit of the first range extender is determined. The first target power generation value is determined based on the first power generation limit, the second power generation limit, the third power generation limit, the fourth power generation limit, and the first power generation request value.

4. The method according to claim 2 or 3, characterized in that, Based on the first target power generation value, the first target speed and first target torque of the first range extender are determined, including: The feedforward mechanical power of the first range extender is determined based on the power generation efficiency of the first range extender and the first target power generation value. Calculate the power difference between the first actual power generation value of the first range extender at the current moment and the first target power generation value; The feedback power generation of the first range extender is calculated based on the power difference and the first actual power generation value. Based on the feedforward mechanical power and the feedback power generation, the first target speed and the first target torque of the first range extender are determined.

5. The method according to claim 2, characterized in that, Dynamically adjusting the first actual speed of the first range extender at the current moment to the first target speed to indirectly control the speed of the front axle motor includes: Obtain the actual front axle motor speed and the target front axle motor speed; Calculate the speed difference between the actual front axle motor speed and the target front axle motor speed; Based on the speed difference, determine the speed adjustment gradient to dynamically adjust the first actual speed to the first target speed; According to the speed adjustment gradient, the first actual speed of the first range extender is dynamically adjusted to the first target speed, thereby indirectly controlling the speed of the front axle motor.

6. The method according to claim 4, characterized in that, Based on the feedforward mechanical power and the feedback power generation, the first target speed and the first target torque of the first range extender are determined, including: The torque compensation value of the first range extender is determined based on the first actual power generation value and the first target power generation value. The first target mechanical power is determined based on the feedforward mechanical power and the feedback power generation, and the required power generation speed and required power generation torque corresponding to the first target mechanical power are found. The required power generation speed is determined as the first target speed; The first target torque is determined based on the torque compensation value and the required power generation torque.

7. The method according to claim 1, characterized in that, Based on the real-time vehicle speed, the power generation request value is split into a first power generation request value and a second power generation request value, including: When the real-time vehicle speed is less than the first vehicle speed, the power generation request value is determined as the second power generation request value; When the real-time vehicle speed is greater than or equal to the first vehicle speed and less than the second vehicle speed, the power generation request value is split into a first power generation request value and a second power generation request value, wherein the first vehicle speed is less than the second vehicle speed; When the real-time vehicle speed is greater than or equal to the second vehicle speed, the power generation request value is split into a first power generation request value and a second power generation request value.

8. A range extender control device, characterized in that, include: The acquisition module is configured to acquire the power generation request value for the four-wheel drive range-extended vehicle at the current moment; The splitting module is configured to, if it is determined that the power drive mode of the four-wheel drive range-extended vehicle is a four-wheel drive mode, collect the real-time vehicle speed of the four-wheel drive range-extended vehicle at the current moment, and split the power generation request value into a first power generation request value and a second power generation request value based on the real-time vehicle speed. The first sending module is configured to send a first control command to the first range extender controller, so that the first range extender controller executes the first control command and controls the first range extender based on the first power generation request value to indirectly regulate the torque and speed of the front axle motor. The second sending module is configured to send a second control command to the second range extender, so that the second range extender controller executes the second control command and controls the second range extender based on the second power generation request value to indirectly regulate the torque and speed of the rear axle motor.

9. A four-wheel drive range-extended electric vehicle, characterized in that, Including the vehicle controller; A first range extender controller and a second range extender controller are respectively communicatively connected to the vehicle controller; A first range extender that is communicatively connected to the first range extender controller, and a front axle motor that is electrically connected to the first range extender; A second range extender that is communicatively connected to the second range extender controller, and a rear axle motor that is electrically connected to the second range extender; The vehicle controller includes the range extender control device as described in claim 8.

10. A readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 7.

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