Closed-loop-based rotating speed control method and system for extended-range automobile

Abstract

The invention belongs to the technical field of automobile rotating speed control, and discloses a closed-loop-based rotating speed control method and system.The method comprises the steps that the target rotating speed of a motor is obtained according to the required generation power of a range extender, the speed difference between the target rotating speed and the actual rotating speed is calculated, and a relation table between the preset speed difference and the target acceleration is searched for; obtaining a target acceleration, and obtaining a motor speed regulation torque according to the target acceleration; obtaining actual acceleration according to the actual rotating speed, obtaining actual acceleration torque of the motor according to the actual acceleration, and obtaining reverse dragging force of the motor according to the actual acceleration torque of the motor; and the motor output torque is obtained according to the motor speed regulation torque and the motor reverse dragging force. According to the method, a rotating speed control algorithm can be accurately provided, and normal operation can be carried out according to the performance of the designed range extender under various complex working conditions such as urgent acceleration, urgent deceleration and rapid shutdown.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile speed control, and in particular relates to a closed-loop speed control method and system for an extended-range vehicle. Background Art

[0002] With the increasing popularity of new energy vehicles, extended-range vehicles have become one of the mainstream models in the current society. However, the range extender consists of an engine and a motor in series. The coordinated control of the two is the difficulty of the range extender control. One of the most important problems is the control of non-steady-state conditions. During the change of engine speed, the motor and the engine are rigidly connected, so the speed values ​​of the two remain constant and equal; the engine and the motor need to output torque, and the torque values ​​of the two can be different, and they work together on the range extender to achieve an increase or decrease in speed. The increase or decrease in speed is achieved through two inputs (engine torque and motor torque), and speed fluctuations or overshoot problems will occur during the control process.

[0003] At present, in the existing technology, the control of motor speed is generally carried out through PID to calculate the motor torque, that is, the PID calculation is performed through the motor target speed and the motor actual speed to obtain the torque that the motor needs to compensate; for example, when the vehicle needs the range extender to generate electricity, the range extender is required to provide engine power. At this time, a motor target speed should be set, and the motor outputs the motor torque through PID control to achieve the target speed to support the normal power generation of the range extender.

[0004] However, the above-mentioned prior art is limited to general usage scenarios. During actual driving, vehicles may encounter various complex working conditions. Such algorithms are difficult to adapt to various working conditions of vehicles, such as rapid acceleration, rapid deceleration, rapid shutdown, etc. For example, during rapid acceleration of the vehicle with a large throttle, the range extender needs to provide greater power. At this time, a higher target speed should be set, and the motor outputs the motor torque through PID control to achieve the target speed. However, the PID algorithm often brings a large overshoot when responding quickly, resulting in large fluctuations in the engine speed; and the P value and I value of the PID algorithm are difficult to calibrate because the P value and I value are generally one-dimensional or two-dimensional tables.

[0005] Therefore, a speed control algorithm is needed, which can ensure the normal operation of the range extender according to the designed performance regardless of various complex operating conditions such as sudden acceleration, sudden deceleration, and rapid shutdown. Summary of the invention

[0006] Based on this, the present application proposes a closed-loop speed control method and system for extended-range vehicles, aiming to accurately provide a speed control algorithm so that the vehicle can operate normally according to the designed range extender performance regardless of various complex operating conditions such as sudden acceleration, sudden deceleration, and rapid shutdown.

[0007] A first aspect of the present application provides a closed-loop speed control method for a range-extended vehicle, the method comprising: The target speed of the motor is obtained according to the required power generation power of the range extender, the speed difference between the target speed and the actual speed is calculated, the relationship table between the preset speed difference and the target acceleration is searched, the target acceleration is obtained, and the motor speed regulating torque is obtained according to the target acceleration; The actual acceleration is obtained according to the actual speed, the actual acceleration torque of the motor is obtained according to the actual acceleration, and the motor reverse drag force is obtained according to the actual acceleration torque of the motor; The motor output torque is obtained according to the motor speed regulation torque and the motor reverse drag force.

[0008] Compared with the prior art, the present application provides a closed-loop speed control method for a range-extended vehicle. The method first calculates the target speed of the motor according to the required power generation power of the range extender. This process ensures that the operating state of the motor matches the power generation demand of the range extender, thereby avoiding energy waste and unnecessary power loss; the target acceleration can be obtained by calculating the speed difference between the target speed and the actual speed, and looking up the relationship table between the preset speed difference and the target acceleration. This link ensures that the motor can respond quickly to speed changes by establishing the relationship between the speed difference and the acceleration, thereby improving the dynamic response capability of the system; the motor speed regulation torque is calculated according to the target acceleration to ensure The motor can run smoothly under the required acceleration. This process avoids the overshoot of the motor during acceleration by precisely controlling the torque, thus improving the smoothness and comfort of driving. The actual acceleration is calculated by the actual speed, and the actual acceleration torque of the motor is further obtained. The motor back-drag force is calculated according to the actual acceleration torque. This feedback mechanism enables the system to monitor the running state of the motor in real time and make corresponding adjustments to ensure the stability of the motor under various working conditions. Finally, the motor output torque is obtained according to the motor speed regulation torque and the motor back-drag force. This optimization process ensures that the motor can maintain the best output performance under different working conditions, thus improving the power response and energy efficiency of the extended-range vehicle. Therefore, this method provides an accurate algorithm for speed control, which can operate normally according to the designed range extender performance regardless of various complex working conditions such as rapid acceleration, rapid deceleration, and rapid shutdown.

[0009] As an optional implementation manner of the first aspect, the step of obtaining the target speed of the motor according to the required power generation power of the range extender includes: Subtract the power required by the vehicle auxiliary equipment from the power required by the current vehicle driving to obtain the required power generation power of the range extender; The output power of the motor is decomposed from the required power generation. According to the output power, torque and efficiency of the motor, the target speed of the motor is obtained. The calculation formula of the target speed of the motor is: , Wherein, n represents the target speed of the motor, P represents the required power generation of the range extender, η represents the efficiency of the motor, and T represents the torque of the motor.

[0010] As an optional implementation manner of the first aspect, the step of obtaining the motor speed regulation torque according to the target acceleration includes: Determine the motor mass and rotor winding radius, and combine them with the target acceleration to obtain the motor speed regulation torque. The calculation formula for the motor speed regulation torque is: , in, Indicates the motor speed regulation torque, represents the target acceleration, m represents the motor mass, and r represents the rotor winding radius.

[0011] As an optional implementation manner of the first aspect, the step of obtaining the actual acceleration according to the actual rotation speed includes: Get the actual speed of the motor, use a first-order filter to smooth the actual speed of the motor, and get the filtered speed. The calculation formula for the filtered speed is: , in, and They represent the speed at time t and time t-1 respectively, α represents the filtering parameter, Indicates the speed before filtering at time t; The least squares method is used to fit the filtered speed to obtain the actual acceleration of the motor. The calculation formula for the actual acceleration is: , in, Indicates the actual acceleration of the motor, represents the interval speed, Indicates the interval time.

[0012] As an optional implementation manner of the first aspect, the step of obtaining the actual acceleration torque of the motor according to the actual acceleration includes: According to the motor mass and the rotor winding radius, combined with the actual acceleration, the actual acceleration torque of the motor is obtained. The calculation formula of the actual acceleration torque of the motor is: , in, Indicates the actual acceleration torque of the motor. Indicates the actual acceleration.

[0013] As an optional implementation manner of the first aspect, the formula for obtaining the motor reverse drag force according to the actual acceleration torque of the motor is: , in, Indicates the motor's reverse drag. Indicates the motor torque of the previous cycle.

[0014] As an optional implementation manner of the first aspect, the formula for obtaining the motor output torque according to the motor speed regulation torque and the motor reverse drag force is: , in, Indicates the motor output torque.

[0015] A second aspect of an embodiment of the present application provides a closed-loop speed control system for a range-extended vehicle, the system comprising: The target torque calculation module is used to obtain the target speed of the motor according to the required power generation of the range extender, calculate the speed difference between the target speed and the actual speed, find the relationship table between the preset speed difference and the target acceleration, obtain the target acceleration, and obtain the motor speed regulation torque according to the target acceleration; An actual anti-drag force calculation module is used to obtain the actual acceleration according to the actual speed, obtain the actual acceleration torque of the motor according to the actual acceleration, and obtain the motor anti-drag force according to the actual acceleration torque of the motor; The motor output torque calculation module is used to obtain the motor output torque according to the motor speed regulation torque and the motor reverse drag force.

[0016] A third aspect of an embodiment of the present application provides a computer device, which includes a memory, a processor, and a processing program stored in the memory and executable on the processor, wherein the processing program, when executed by the processor, implements the above-mentioned closed-loop speed control method for an extended-range vehicle.

[0017] A fourth aspect of an embodiment of the present application provides a storage medium, on which a processing program is stored. When the processing program is run by a processor, the above-mentioned closed-loop speed control method for an extended-range vehicle is executed.

[0018] Additional aspects and advantages of the present application will be given in part in the following description, and in part will become apparent from the following description, or will be understood through the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a flow chart of a closed-loop speed control method for a range-extended vehicle proposed in the first embodiment of the present application; Figure 2 This is a simulation data diagram of a rapid acceleration process of a certain light-duty extended-range light truck in the first embodiment of the present application; Figure 3 This is a simulation data diagram of a sudden deceleration process of a certain light-duty extended-range light truck in the first embodiment of the present application; Figure 4 This is a schematic structural diagram of a closed-loop speed control system for a range-extended vehicle proposed in the second embodiment of the present application.

[0020] The following specific implementation methods will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0022] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here. In addition, the "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally represents that the objects associated with each other are in an "or" relationship.

[0023] In order to illustrate the technical solution described in this application, a specific embodiment is provided below for illustration.

[0024] See also Figure 1 , is a flow chart of a closed-loop speed control method for a range-extended vehicle proposed in the first embodiment of the present application, wherein the proposed method includes: S01: Obtain the target speed of the motor according to the required power generation power of the range extender.

[0025] First of all, it is necessary to clarify the required power of the range extender under specific operating conditions, which is usually determined by factors such as the vehicle's power requirements, driving speed, and load.

[0026] Subtract the power required by the vehicle auxiliary equipment from the power required by the current vehicle driving to obtain the required power generation power of the range extender; The required power generation can be calculated using the following formula: P 需求 =P 车辆 +P 辅助设备 , Among them, P 车辆 is the power required for the vehicle to move, P 辅助设备 It is the power required by vehicle auxiliary equipment (such as air conditioning, lighting, etc.).

[0027] Next, the output power of the motor is decomposed from the required power generation power; Based on the required power generation power of the range extender system, the required power generation power is usually decomposed into motor output power and engine output power.

[0028] Motor output power P 电机 and engine output power P 发动机 The following relationship exists: P 电机 +P 发动机 ==P 需求， The appropriate power distribution ratio can be determined according to the characteristics of the motor and engine.

[0029] Furthermore, the target speed of the motor is obtained according to the output power of the motor, the torque of the motor and the efficiency of the motor. The calculation formula of the target speed of the motor is: , Wherein, n represents the target speed of the motor, P represents the required power generation of the range extender, η represents the efficiency of the motor, and T represents the torque of the motor.

[0030] Finally, the target speed is selected based on the motor's high efficiency point, the engine's low fuel consumption point, and the required power generation; Exemplarily, the present invention obtains the target speed of the motor according to the required power generation power of the range extender, and forms a calibration table that is easy to select, as shown in Table 1 below.

[0031] Table 1 Selection table of required power generation and target motor speed S02: Calculate the speed difference between the target speed and the actual speed, search the relationship table between the preset speed difference and the target acceleration, and obtain the target acceleration; First, the speed difference n dev The calculation formula is: n dev =n tar −n act , Among them, n tar is the target speed of the motor, n act is the actual speed of the motor.

[0032] Next, according to the calculated speed difference n dev , find the pre-established relationship between the speed difference and the target acceleration in Table 1, and get the target acceleration a tar This table is usually obtained through experiments or simulations and can reflect the response characteristics of the motor under different speed differences.

[0033] If the required power generation increases, the target acceleration a tar A positive value indicates that acceleration is required to increase the motor speed, as shown in Table 2; Table 2 Relationship between speed difference and target acceleration (positive value) If the required power generation decreases, the target acceleration a tar A negative value indicates that deceleration is required to reduce the motor speed, as shown in Table 3.

[0034] Table 3 Relationship between speed difference and target acceleration (negative value) Finally, the motor control signal can be adjusted according to the calculated target acceleration to achieve the required acceleration or deceleration. During the adjustment process, the actual speed n of the motor is continuously monitored. act , and continuously correct the target acceleration based on the feedback information to ensure that the motor can stably reach the target speed.

[0035] S03: Obtain the motor speed regulation torque according to the target acceleration.

[0036] Specifically, the motor mass and the rotor winding radius are determined, and combined with the target acceleration, the motor speed regulation torque is obtained. The calculation formula of the motor speed regulation torque is: , in, Indicates the motor speed regulation torque, represents the target acceleration, m represents the motor mass, and r represents the rotor winding radius.

[0037] S04: Obtain actual acceleration according to actual rotation speed.

[0038] First, the actual speed of the motor is obtained, and then the actual speed of the motor is smoothed using a first-order filter to obtain the filtered speed. The calculation formula for the filtered speed is: , in, and They represent the speed at time t and time t-1 respectively, α represents the filtering parameter, Indicates the speed before filtering at time t; Next, the least squares method is used to fit the filtered speed to obtain the actual acceleration of the motor. The calculation formula for the actual acceleration is: , in, Indicates the actual acceleration of the motor, represents the interval speed, Indicates the interval time.

[0039] Finally, during the calculation process, pay attention to processing abnormal speed values. You can set a threshold to filter out obviously unreasonable speed data to ensure that the calculated acceleration value is stable and reliable.

[0040] For example, Figure 2 and Figure 3 As shown in the figure, it is a simulation data diagram of the motor output torque, speed and actual acceleration of a certain light-duty extended-range light truck during rapid acceleration and rapid deceleration after smoothing and abnormal value processing.

[0041] S05: Obtain the actual acceleration torque of the motor according to the actual acceleration.

[0042] Specifically, according to the motor mass and the rotor winding radius, combined with the actual acceleration, the actual acceleration torque of the motor is obtained. The calculation formula of the actual acceleration torque of the motor is: , in, Indicates the actual acceleration torque of the motor. Indicates the actual acceleration.

[0043] S06: Obtain the motor reverse force according to the actual acceleration torque of the motor.

[0044] Specifically, the formula for obtaining the motor's reverse drag force based on the motor's actual acceleration torque is: , in, Indicates the motor's reverse drag. Indicates the motor torque of the previous cycle.

[0045] It should be noted that during the calculation process, the motor torque of the previous cycle needs to be And the resulting motor anti-drag force A first-order filtering process is performed to smooth the data and reduce the effects of noise.

[0046] S07: Obtain the motor output torque according to the motor speed regulation torque and the motor reverse drag force.

[0047] Specifically, the formula for obtaining the motor output torque according to the motor speed regulation torque and the motor reverse drag force is: , in, Indicates the motor output torque.

[0048] In summary, the present application provides a closed-loop speed control method for a range-extended vehicle. The method first calculates the target speed of the motor according to the required power generation power of the range extender. This process ensures that the operating state of the motor matches the power generation demand of the range extender, thereby avoiding energy waste and unnecessary power loss; the target acceleration can be obtained by calculating the speed difference between the target speed and the actual speed, and looking up the relationship table between the preset speed difference and the target acceleration. This link ensures that the motor can respond quickly to speed changes by establishing the relationship between the speed difference and the acceleration, thereby improving the dynamic response capability of the system; the motor speed regulation torque is calculated according to the target acceleration to ensure that the motor It can run smoothly under the required acceleration. This process avoids the overshoot of the motor during acceleration by precisely controlling the torque, improving the smoothness and comfort of driving. The actual acceleration is calculated by the actual speed, and the actual acceleration torque of the motor is further obtained. The motor back-drag force is calculated according to the actual acceleration torque. This feedback mechanism enables the system to monitor the running state of the motor in real time and make corresponding adjustments to ensure the stability of the motor under various working conditions. Finally, the motor output torque is obtained according to the motor speed torque and the motor back-drag force. This optimization process ensures that the motor can maintain the best output performance under different working conditions, improving the power response and energy efficiency of the extended-range vehicle. Therefore, this method provides an accurate algorithm for speed control, which can operate normally according to the designed range extender performance regardless of various complex working conditions such as rapid acceleration, rapid deceleration, and rapid shutdown.

[0049] See also Figure 4 , which is a schematic diagram of a closed-loop speed control system for a range-extended vehicle proposed in the second embodiment of the present application, and the system includes: The target torque calculation module 10 is used to obtain the target speed of the motor according to the required power generation of the range extender, calculate the speed difference between the target speed and the actual speed, find the relationship table between the preset speed difference and the target acceleration, obtain the target acceleration, and obtain the motor speed regulating torque according to the target acceleration; The actual anti-drag force calculation module 20 is used to obtain the actual acceleration according to the actual rotation speed, obtain the actual acceleration torque of the motor according to the actual acceleration, and obtain the motor anti-drag force according to the actual acceleration torque of the motor; The motor output torque calculation module 30 is used to obtain the motor output torque according to the motor speed regulation torque and the motor reverse drag force.

[0050] On the other hand, the present application also proposes a computer device, which includes a memory, a processor, and a processing program stored in the memory and executable on the processor. When the processing program is executed by the processor, the above-mentioned closed-loop speed control method for an extended-range vehicle is implemented.

[0051] On the other hand, the present application further proposes a storage medium on which a processing program is stored. When the processing program is run by a processor, the above-mentioned closed-loop speed control method for an extended-range vehicle is executed.

[0052] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0053] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0054] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A closed-loop speed control method for a range-extended vehicle, characterized in that: The method comprises: The target speed of the motor is obtained according to the required power generation power of the range extender, the speed difference between the target speed and the actual speed is calculated, the relationship table between the preset speed difference and the target acceleration is searched, the target acceleration is obtained, and the motor speed regulating torque is obtained according to the target acceleration; The actual acceleration is obtained according to the actual speed, the actual acceleration torque of the motor is obtained according to the actual acceleration, and the motor reverse drag force is obtained according to the actual acceleration torque of the motor; The motor output torque is obtained according to the motor speed regulation torque and the motor reverse drag force.

2. The method according to claim 1, characterized in that: The step of obtaining the target speed of the motor according to the required power generation power of the range extender comprises: Subtract the power required by the vehicle auxiliary equipment from the power required by the current vehicle driving to obtain the required power generation power of the range extender; The output power of the motor is decomposed from the required power generation. According to the output power, torque and efficiency of the motor, the target speed of the motor is obtained. The calculation formula of the target speed of the motor is: ， Wherein, n represents the target speed of the motor, P represents the required power generation of the range extender, η represents the efficiency of the motor, and T represents the torque of the motor.

3. The method according to claim 1, characterized in that: The step of obtaining the motor speed regulating torque according to the target acceleration comprises: Determine the motor mass and rotor winding radius, and combine them with the target acceleration to obtain the motor speed regulation torque. The calculation formula for the motor speed regulation torque is: ， in, Indicates the motor speed regulation torque, represents the target acceleration, m represents the motor mass, and r represents the rotor winding radius.

4. The method according to claim 3, characterized in that: The step of obtaining the actual acceleration according to the actual rotation speed comprises: Get the actual speed of the motor, use a first-order filter to smooth the actual speed of the motor, and get the filtered speed. The calculation formula for the filtered speed is: ， in, and They represent the speed at time t and time t-1 respectively, α represents the filtering parameter, Indicates the speed before filtering at time t; The least squares method is used to fit the filtered speed to obtain the actual acceleration of the motor. The calculation formula for the actual acceleration is: ， in, Indicates the actual acceleration of the motor, represents the interval speed, Indicates the interval time.

5. The method according to claim 4, characterized in that: The step of obtaining the actual acceleration torque of the motor according to the actual acceleration comprises: According to the motor mass and the rotor winding radius, combined with the actual acceleration, the actual acceleration torque of the motor is obtained. The calculation formula of the actual acceleration torque of the motor is: ， in, Indicates the actual acceleration torque of the motor. Indicates the actual acceleration.

6. The method according to claim 5, characterized in that: The formula for obtaining the motor's reverse drag force based on the actual acceleration torque of the motor is: ， in, Indicates the motor's reverse drag. Indicates the motor torque of the previous cycle.

7. The method according to claim 6, characterized in that: The formula for obtaining the motor output torque according to the motor speed regulating torque and the motor reverse drag force is: ， in, Indicates the motor output torque.

8. A closed-loop speed control system for a range-extended vehicle, characterized in that: The system comprises: The target torque calculation module is used to obtain the target speed of the motor according to the required power generation of the range extender, calculate the speed difference between the target speed and the actual speed, find the relationship table between the preset speed difference and the target acceleration, obtain the target acceleration, and obtain the motor speed regulation torque according to the target acceleration; An actual anti-drag force calculation module is used to obtain the actual acceleration according to the actual speed, obtain the actual acceleration torque of the motor according to the actual acceleration, and obtain the motor anti-drag force according to the actual acceleration torque of the motor; The motor output torque calculation module is used to obtain the motor output torque according to the motor speed regulation torque and the motor reverse drag force.

9. A computer device, characterized in that: The computer device includes a memory, a processor, and a processing program stored in the memory and executable on the processor. When the processing program is executed by the processor, a closed-loop speed control method for an extended-range vehicle is implemented as described in any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium stores a processing program, and when the processing program is executed by the processor, the closed-loop speed control method for an extended-range vehicle as claimed in any one of claims 1 to 7 is implemented.

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