Hybrid vehicle control method and vehicle control unit

Abstract

A method for controlling a hybrid vehicle (1000) including an engine (10) that selectively outputs power to the wheels, a drive motor (20) that outputs power to the wheels, a generator (30) that is connected to the engine (10) and is driven by the engine (10) to generate power, and a power battery (40) that supplies power to the drive motor (20) includes the steps of acquiring driving parameters of the hybrid vehicle (1000), controlling the engine (10), the drive motor (20) and the generator (30) based on the driving parameters and controlling charging and discharging of the power battery (40) so that the engine (10) operates in an eco zone, and comparing the equivalent fuel consumption of the hybrid vehicle (1000) in a series mode, a parallel mode and an EV mode to select an operating mode with the lowest equivalent fuel consumption as a current operating mode of the hybrid vehicle (1000). A vehicle control unit (2000) is further disclosed.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This disclosure is based on and claims priority to a Chinese patent application with application number 202110228793.2, filed on March 2, 2021, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to the technical field of vehicles, and in particular to a control method and a vehicle control unit for a hybrid vehicle. [Background technology]

[0003] With the development of hybrid vehicles, users' requirements for the economy of hybrid vehicles are becoming higher and higher. Current hybrid system architectures and policies cannot optimize the energy consumption of vehicles, so the requirements for the economy of hybrid vehicles cannot be met, and the expectations of users cannot be met.

[0004] For example, in a conventional pure range extender type hybrid vehicle, the system architecture requires the engine to drive a generator to generate electricity, and then the electricity is provided to a traction motor to drive the vehicle. Therefore, even in the highly efficient medium- to high-speed mode in which the engine is directly driven, energy must be converted by the generator, resulting in large losses and preventing optimal energy consumption in the medium- to high-speed mode, further reducing the economic efficiency of the vehicle. Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure seeks to at least partially solve one of the technical problems in the related art. Therefore, a first objective of the present disclosure is to provide a control method for a hybrid vehicle, which allows the hybrid vehicle to operate in an operation mode with the lowest equivalent fuel consumption based on driving parameters and consume less energy, thereby effectively improving the economy of the hybrid vehicle and meeting the user's usage expectations.

[0006] A second object of the present disclosure is to provide a computer-readable storage medium.

[0007] A third object of the present disclosure is to provide a vehicle control unit. [Means for solving the problem]

[0008] In order to achieve the above object, an embodiment of a first aspect of the present disclosure provides a control method for a hybrid vehicle, the hybrid vehicle including an engine that selectively outputs power to the wheels, a drive motor that outputs power to the wheels, a generator connected to the engine and driven by the engine to generate electricity, and a power battery that supplies power to the drive motor and is charged based on an alternating current output from the generator or the drive motor, and has a capacity equal to or greater than a first predetermined capacity, the control method including the steps of acquiring driving parameters of the hybrid vehicle, controlling the engine, the drive motor, and the generator based on the driving parameters, and performing charge / discharge control on the power battery, thereby causing the engine to operate in an eco zone, and comparing the equivalent fuel efficiency of the hybrid vehicle in series mode, parallel mode, and EV mode, and selecting the operating mode with the lowest equivalent fuel efficiency as the current operating mode of the hybrid vehicle.

[0009] In the control method for a hybrid vehicle according to the embodiment of the present disclosure, the driving parameters of the hybrid vehicle are acquired, the engine, the drive motor, and the generator are controlled based on the driving parameters, and the charging and discharging of the power battery are controlled so that the engine always operates in the eco zone when the engine is in operation, and the equivalent fuel efficiency of the hybrid vehicle is compared in the series mode, the parallel mode, and the EV mode, and the operation mode with the lowest equivalent fuel efficiency is selected as the current operation mode of the hybrid vehicle, so that the hybrid vehicle operates in the operation mode with the lowest equivalent fuel efficiency based on the driving parameters, and energy consumption is low, which effectively improves the economy of the hybrid vehicle and meets the user's expectations for use.

[0010] In order to achieve the above object, a computer-readable storage medium according to an embodiment of the second aspect of the present disclosure stores a hybrid vehicle control program that, when executed by a processor, realizes the above-mentioned hybrid vehicle control method.

[0011] The computer-readable storage medium according to the embodiment of the present disclosure uses the above-mentioned hybrid vehicle control method to operate the hybrid vehicle in an operating mode with the lowest equivalent fuel efficiency based on driving parameters, and consumes less energy, thereby effectively improving the economical efficiency of the hybrid vehicle and meeting users' usage expectations.

[0012] In order to achieve the above object, a vehicle control unit according to an embodiment of a third aspect of the present disclosure includes a memory, a processor, and a hybrid vehicle control program stored in the memory and executable by the processor, and when the processor executes the hybrid vehicle control program, it realizes the above-mentioned hybrid vehicle control method.

[0013] The vehicle control unit according to the embodiment of the present disclosure uses the above-mentioned hybrid vehicle control method to operate the hybrid vehicle in an operating mode with the lowest equivalent fuel efficiency based on the driving parameters, and consumes less energy, thereby effectively improving the economical efficiency of the hybrid vehicle and meeting users' usage expectations.

[0014] Additional aspects and advantages of the disclosure will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the disclosure. [Brief description of the drawings]

[0015] [Figure 1a] 1 is a schematic configuration diagram of a hybrid system according to a first embodiment of the present disclosure. [Figure 1b] FIG. 11 is a schematic configuration diagram of a hybrid system according to a second embodiment of the present disclosure. [Diagram 2] FIG. 2 is a schematic diagram showing an optimal eco-point of an engine according to one embodiment of the present disclosure. [Diagram 3] FIG. 13 is a diagram illustrating the proportion of different driving methods in a power-starved mode according to an embodiment of the present disclosure. [Figure 4] FIG. 1 is a schematic diagram showing an eco-line of an engine in series mode according to one embodiment of the present disclosure. [Diagram 5] FIG. 1 is a schematic diagram showing an eco-line of an engine in parallel mode according to one embodiment of the present disclosure. [Figure 6a] - [Figure 6b] 4 is a control flowchart of a hybrid system according to an embodiment of the present disclosure. [Figure 7] FIG. 2 is a schematic diagram illustrating a control policy of a hybrid system according to an embodiment of the present disclosure. [Figure 8a] - [Figure 8b] FIG. 4 is a schematic diagram showing the efficiency of a traction motor according to an embodiment of the present disclosure. [Figure 9] FIG. 2 is a schematic diagram illustrating efficiency and operating points of an engine according to one embodiment of the present disclosure. [Figure 10] FIG. 11 is a schematic configuration diagram of a hybrid system according to a third embodiment of the present disclosure. [Figure 11] 1 is a schematic diagram of a hybrid vehicle according to an embodiment of the present disclosure. [Figure 12] 4 is a flowchart of a control method for a hybrid vehicle according to an embodiment of the present disclosure. [Figure 13] FIG. 2 is a schematic diagram of a vehicle control unit according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the embodiments of the present disclosure will be described in detail, and examples of the embodiments are shown in the drawings, in which the same or similar reference numerals throughout represent the same or similar elements, or elements having the same or similar functions. The embodiments described below with reference to the drawings are illustrative and are for interpreting the present disclosure, and should not be understood as limiting the present disclosure.

[0017] Hereinafter, a hybrid system 100, a hybrid vehicle 1000 and a control method thereof, a vehicle control unit 2000, and a computer-readable storage medium according to an embodiment of the present disclosure will be described with reference to the drawings.

[0018] 1a is a schematic diagram of a hybrid system 100 according to an embodiment of the present disclosure. As shown in FIG. 1a, the hybrid system 100 may include an engine 10, a traction motor 20, a generator 30, a power battery 40, and a controller 50.

[0019] The engine 10 selectively outputs power to the wheels. The drive motor 20 outputs power to the wheels. The generator 30 is connected to the engine 10 and is driven by the engine 10 to generate power. The power battery 40 supplies power to the drive motor 20, is charged based on the AC current output from the generator 30 or the drive motor 20, and has a capacity equal to or greater than a first predetermined capacity. The controller 50 is configured to acquire driving parameters of the hybrid vehicle 1000, control the engine 10, the drive motor 20, and the generator 30 based on the driving parameters, and perform charge / discharge control on the power battery 40 so that the engine 10 operates in an eco zone, and select an operation mode with the lowest equivalent fuel consumption as the current operation mode of the hybrid vehicle 1000 by comparing the equivalent fuel consumption of the hybrid vehicle 1000 in the series mode, the parallel mode, and the EV mode.

[0020] Specifically, the engine 10 may be an Atkinson cycle engine 10, and a clutch C1 is provided between the engine 10 and the wheel side, and the controller 50 controls the disengagement and engagement of the clutch C1 to control the connection and disengagement between the engine 10 and the wheel side, so that the engine 10 can selectively output power to the wheel side, thus realizing direct drive of the engine 10, i.e., direct output of power by the engine 10 to the wheel side. For example, when the controller 50 controls to disengage the clutch C1, the engine 10 is separated from the wheel side and does not directly output power to the wheel side, whereas when the controller 50 controls to engage the clutch C1, the engine 10 is connected to the wheel side and directly outputs power to the wheel side, thereby realizing direct drive of the engine 10. Compared with the conventional pure range extender type hybrid vehicle, this architecture has a direct drive path of the engine 10, so that the conventional pure range extender type hybrid vehicle lacks a direct drive path of the engine 10, and even if the engine 10 is very efficient (even if the rotation speed and torque of the engine 10 are both highly efficient), the energy conversion loss caused by generating electricity using the generator 30 and then providing the electricity to the drive motor 20 for driving, and the further energy conversion loss caused by the power battery 40 frequently operating in a charging and discharging state can be avoided, thereby effectively improving the economic efficiency of the vehicle.

[0021] The driving motor 20 may be a flat wire motor, and a rectangular coil is used as the stator winding of the flat wire motor, which improves the space factor in the stator slot and reduces the volume of the motor, thereby greatly improving the power density of the motor, and the driving motor 20 is directly connected to the wheel side by a gear, and the controller 50 outputs power to the wheel side by controlling the operation of the driving motor 20. In some implementations of the present disclosure, the driving motor 20 and the generator 30 are arranged in parallel, and compared with other installation methods, such as the method in which the driving motor 20 and the generator 30 are arranged coaxially, the parallel arrangement method in this embodiment has lower requirements for the design of the motor, making it easier to install the high-power generator 30 and lowering the cost.

[0022] The generator 30 may be a flat wire motor, and the generator 30 is connected between the clutch C1 and the engine 10 and directly connected to the engine 10 by gears. The controller 50 can drive the generator 30 to generate electricity by controlling the operation of the engine 10. The generated electricity can be controlled by the controller 50 to charge the power battery 40 or supply power to the drive motor 20.

[0023] In some implementations of the present disclosure, as shown in Fig. 1a, the hybrid system 100 may further include a transmission 70 and a final reduction gear 80. As shown in Fig. 1b, the transmission 70 may further include gears Z1, Z2, Z3, and Z4, in which the central axis of the gear Z1 is connected to one end of the clutch C1, the gear Z1 meshes with the gear Z2, the gear Z2 meshes with the gear Z3, the central axis of the gear Z3 is connected to the driving motor 20, the central axis of the gear Z2 is connected to the central axis of the gear Z4, and the gear Z4 meshes with the final reduction gear of the final reduction gear 80. Of course, the transmission 70 may use other structures, and the specifics are not limited here.

[0024] The power battery 40 may be a blade battery, and the power battery 40 may be electrically connected to the drive motor 20 and the generator 30, respectively, and under the control of the controller 50, the power battery 40 may power the drive motor 20 or may be charged based on the alternating current output from the generator 30 or the drive motor 20, i.e., the power battery 40 may be charged by the generator 30 or the drive motor 20. In addition, the capacity of the power battery 40 is equal to or larger than a first predetermined capacity, for example, the first predetermined capacity is 5 kWh to 25 kWh. Since the power battery 40 has a large capacity, the power battery 40 has an excellent buffering effect by charging and discharging the power battery 40, and can adjust the operating efficiency of the engine 10. In this way, the engine 10 can always operate in the eco zone when in operation; otherwise, the operating efficiency of the engine 10 is low and the engine 10 is in a non-operating state. The engine 10 operating in the eco zone means that the engine 10 always operates in a high efficiency state. In this embodiment, the engine 10 operates in a state of 38% thermal efficiency or higher. Furthermore, the large-capacity power battery 40 allows the hybrid system 100 to realize long-term running in EV mode, and the operating time of the engine 10 is shorter and fuel consumption is reduced.

[0025] The controller 50 is connected to the engine 10, the drive motor 20, the generator 30, the power battery 40, and the clutch C1, respectively, and can realize control by transmitting control signals to the engine 10, the drive motor 20, the generator 30, the power battery 40, and the clutch C1. The controller 50 acquires driving parameters of the hybrid vehicle 1000, and in some implementations of the present disclosure, the driving parameters include at least one of the wheel side required torque, the SOC of the power battery 40, and the vehicle speed of the hybrid vehicle 1000, and the wheel side required torque is the vehicle required torque. The controller 50 controls the engine 10, the drive motor 20, and the generator 30 based on the driving parameters, and performs charge / discharge control on the power battery 40, so that the engine 10 operates in the eco zone, and selects the operation mode with the lowest equivalent fuel consumption as the current operation mode of the hybrid vehicle 1000 by comparing the equivalent fuel consumption of the hybrid vehicle 1000 in the series mode, the parallel mode, and the EV mode. The comparison of the equivalent fuel efficiency is based on the engine 10 operating in an eco zone. For example, when the engine 10 operates in a 25 kW eco zone, the fuel efficiency in the parallel mode may be lower than that in the serial mode and may also be lower than that in the EV mode when combined with driving parameters such as the wheel side torque. In this case, the hybrid vehicle 1000 is controlled to run in the parallel mode, while if the fuel efficiency in the EV mode is lower than that in the parallel mode and is also lower than that in the serial mode, the hybrid vehicle 1000 is controlled to run in the EV mode. The equivalent fuel efficiency means the sum of the fuel consumed by the engine 10 itself and the fuel equivalent to the power consumed by the power battery 40. The power consumed by the power battery 40 may be converted into fuel based on an empirical value to obtain the fuel equivalent to the power consumed by the power battery 40. When the power battery 40 is charged, the fuel equivalent to the power consumed by the power battery 40 is a negative value, and when the power battery 40 is discharged, the fuel equivalent to the power consumed by the power battery 40 is a positive value.

[0026] In other words, the controller 50 can comprehensively judge the driving parameters of the hybrid vehicle 1000, such as the required torque on the wheel side, the SOC of the power battery 40, the vehicle speed of the hybrid vehicle 1000, and the equivalent fuel efficiency in different operating modes of the hybrid vehicle 1000, and when the power requirements and NVH (Noise, Vibration, Harshness), etc. are satisfied, the controller 50 sets the hybrid vehicle 1000 to the operating mode with the lowest equivalent fuel efficiency, so that the equivalent fuel efficiency of the hybrid vehicle 1000 becomes the lowest in the operating mode, and the hybrid vehicle 1000 has high economic efficiency. The series mode means that the power output between the engine 10 and the wheel side is cut off (i.e., the clutch C1 is in the disengaged state), and the engine 10 drives the generator 30 to generate electricity to provide power to the traction motor 20; in some cases, the engine 10 uses excess energy to charge the power battery 40 through the generator 30; the parallel mode means that the engine 10 and the wheel side are power-coupled (i.e., the clutch C1 is in the engaged state), and in some cases, the engine 10 uses excess energy to charge the power battery 40 through the traction motor 20; and the EV mode means that neither the engine 10 nor the generator 30 is operating, and the power battery 40 supplies power to the traction motor 20. Furthermore, when the hybrid vehicle 1000 operates in series mode, parallel mode or EV mode, the engine 10 always operates in the eco zone by controlling the charging and discharging of the power battery 40, and when comparing the equivalent fuel consumption, the comparison is made based on the engine 10 being in the eco zone, in this way the engine 10 always operates in the eco zone within the range of the operating mode, and the equivalent fuel consumption of the hybrid vehicle 1000 is the lowest, effectively improving the economic efficiency of the hybrid vehicle 1000. In this embodiment, the comprehensive control and cooperation of the large-capacity power battery 40, the engine 10, the drive motor 20 and the generator 30 ensures that the hybrid vehicle 1000 operates in the energy-saving mode.

[0027] In some embodiments of the present disclosure, when the hybrid vehicle 1000 is in series mode, the engine 10 charges the power battery 40 through the generator 30, and when the hybrid vehicle 1000 is in parallel mode, the engine 10 charges the power battery 40 through the traction motor 20. In this embodiment, in series mode and parallel mode, the engine 10 charges the power battery 40 through different motors, which can optimize losses and reduce the energy consumption of the vehicle.

[0028] In some embodiments of the present disclosure, when the engine 10 operates in the Eco Zone, the controller 50 is further configured to control the engine 10 to operate at the optimal Eco Line if the SOC of the power battery 40 is greater than or equal to a first predetermined value, or to control the engine 10 to operate at the optimal Eco Line if the SOC of the power battery 40 is less than the first predetermined value and the output power of the engine 10 is greater than or equal to the wheel side required power, wherein the magnitude of the first predetermined value is inversely correlated with the magnitude of the first predetermined capacity.

[0029] Specifically, when engine 10 operates in the eco zone, if the SOC of power battery 40 is equal to or greater than a first predetermined value, or if the SOC of power battery 40 is less than the first predetermined value and the output power of engine 10 is equal to or greater than the wheel side required power, controller 50 controls engine 10 to operate in the optimal eco zone.

[0030] That is, when the power battery 40 can discharge a certain amount of power, or when the power of the power battery 40 is low but the wheel-side power requirement is small, the hybrid vehicle 1000 can be operated at the optimal eco line. The engine 10 has at least one eco line in the eco zone, and among these eco lines, there is one optimal eco line, and the fuel efficiency of the engine 10 corresponding to the optimal eco line is the lowest, and the fuel efficiency of the hybrid vehicle 1000 is lowest by controlling the engine 10 to operate at the optimal eco line. The magnitude of the first predetermined value is inversely correlated with the magnitude of the first predetermined capacity, and in practical application, the first predetermined value can be obtained by table lookup based on the first predetermined capacity, and the first predetermined value in different modes may be different, for example, the first predetermined value in the series mode may be 17%, and the first predetermined value in the parallel mode may be 25%. In this embodiment, the capacity of the power battery 40 is equal to or greater than a first predetermined capacity, the power battery 40 is a large capacity battery, the first predetermined value may be set low, the SOC of the power battery 40 may be lowered, and the engine 10 can operate at the optimum eco line; by setting the capacity of the power battery 40 to be equal to or greater than the first predetermined capacity, the engine 10 of the hybrid vehicle 1000 can operate at the optimum eco line for more of the time.

[0031] In some embodiments of the present disclosure, when the hybrid vehicle 1000 is in the parallel mode, the controller 50 is further configured to determine a wheel-side required torque, and if the wheel-side required torque is smaller than the output torque of the engine 10 when operating on the eco line, control the engine 10 to operate on the eco line in response to the wheel-side required torque, and control the engine 10 to drive the traction motor 20 to generate electricity so that the power battery 40 is charged by the traction motor 20 using excess energy output from the engine 10, and if the wheel-side required torque is greater than the output torque of the engine 10 when operating on the eco line, control the engine 10 to operate on the eco line, and control the power battery 40 to supply power to the traction motor 20 so that both the power battery 40 and the engine 10 respond to the wheel-side required torque.

[0032] This method is the parallel mode of the hybrid vehicle 1000. In the parallel mode, the large-capacity power battery 40 can supplement torque or absorb excess torque. In other words, the power battery 40 can act as a buffer, allowing the engine 10 to operate in a highly efficient eco zone for a long period of time. In the parallel mode, the equivalent fuel consumption of the hybrid vehicle 1000 is the lowest, and the hybrid vehicle 1000 is highly economical.

[0033] Specifically, the controller 50 may control the clutch C1 to be engaged so as to power-couple the engine 10 and the wheel side, and may also control the engine 10 to operate so as to put the hybrid vehicle 1000 into the parallel mode. In the parallel mode, the controller 50 obtains a wheel side required torque, and compares the wheel side required torque with the output torque of the engine 10 when operating on the eco line.

[0034] If the wheel side required torque is equal to or less than the output torque of the engine 10 when it operates on the eco line, the engine 10 is controlled to operate on the eco line to satisfy the power requirement, and the controller 50 controls the engine 10 to drive the drive motor 20 to generate power and the generator 30 to idle, and the drive motor 20 charges the power battery 40 using the excess energy output from the engine 10, and at this time, the hybrid vehicle 1000 enters a parallel power generation mode in the parallel mode. In other words, the parallel mode includes a parallel power generation mode, and when generating power in the parallel mode, the drive motor 20 generates power, the power of the drive motor 20 is larger, the power replenishment is faster, and the loss due to the idle of the generator 30 is smaller than the loss due to the idle of the drive motor 20, resulting in a higher energy saving effect. Therefore, by generating power using the drive motor 20 in this mode, the economy of the vehicle is further improved, and as the excess energy output from the engine 10 is used to charge the power battery 40, the power of the power battery 40 increases, and the time during which the vehicle operates in the EV mode can be extended, resulting in higher economy.

[0035] If the wheel side required torque is greater than the output torque when the engine 10 is operating on the eco line, the engine 10 is controlled to operate on the eco line and the power battery 40 is controlled to supply power to the drive motor 20. At this time, both the power battery 40 and the engine 10 provide the wheel side required torque to satisfy the power requirement, and the hybrid vehicle 1000 enters the parallel power assist mode in the parallel mode.

[0036] As a result, when the hybrid vehicle 1000 is in the parallel mode, the power battery 40 acts as a buffer so that the operating region of the engine 10 is in the eco zone (i.e., on the eco line) of the efficiency curve, ensuring that the engine 10 always operates in the eco zone, resulting in high economic efficiency for the hybrid vehicle 10. Also, in this embodiment, the capacity of the power battery 40 is equal to or greater than the first predetermined capacity, and the power battery 40 is large, so that it acts as a buffer when the engine 10 is operating, and can supplement torque or absorb excess torque.

[0037] In some other embodiments of the present disclosure, when the hybrid vehicle 1000 is in series mode, the controller 50 is further configured to determine the wheel-side required power based on the wheel-side required torque and vehicle speed, drive the generator 30 to generate power based on the output torque of the engine 10 when operating on the eco line, control the engine 10 to operate on the eco line so as to output power to the wheel side by the traction motor 20, and when the generated power of the generator 30 is greater than the wheel-side required power, charge the power battery 40 using the generator 30 with the excess power, and when the generated power of the generator 30 is less than the wheel-side required power, control the power battery 40 to supply power to the traction motor 20 so that both the engine 10 and the power battery 40 respond to the wheel-side required power.

[0038] This method is the series mode of the hybrid vehicle 1000. In the series mode, the large-capacity power battery 40 can supplement power or absorb excess power. In other words, the power battery 40 can act as a buffer, so that the engine 10 can operate in a highly efficient eco-zone for a long period of time, making the hybrid vehicle 1000 highly economical.

[0039] Specifically, the controller 50 may control the clutch C1 to be disconnected so that the engine 10 cuts off the power output between the engine 10 and the wheel side, and the engine 10 drives the generator 30 to generate electricity, and may output power to the wheel side by the drive motor 20 so that the hybrid vehicle 1000 enters the series mode. In the series mode, the controller 50 controls the engine 10 to operate on the eco line, obtains the wheel side required torque and the vehicle speed of the hybrid vehicle 1000, obtains the wheel side required power based on the wheel side required torque and the vehicle speed of the hybrid vehicle 1000 (specifically, this may be realized using a conventional technique, and is not limited here), and compares the wheel side required power with the generated power of the generator 30. The generated power of the generator 30 is the power generated and output by the generator 30 when driven by the torque output when the engine 10 operates on the eco line. If the power generated by the generator 30 is greater than the power required by the wheel side, the excess power is used to charge the power battery 40 by the generator 30, and if the power generated by the generator 30 is equal to or less than the power required by the wheel side, the power battery 40 is controlled to supply power to the drive motor 20, and at this time, both the engine 10 and the power battery 40 provide the power required by the wheel side to guarantee the power requirement.

[0040] In addition, in the series mode, when comparing the power, it is possible to avoid control deviations caused by the inability of the generating and driving powers to follow each other with perfect high efficiency when using torque comparison.

[0041] As a result, when the hybrid vehicle 1000 is in series mode, the power battery 40 acts as a buffer so that the operating region of the engine 10 is in the eco zone (i.e., on the eco line) of the efficiency curve, ensuring that the engine 10 always operates in the eco zone, resulting in high economic efficiency for the hybrid vehicle 10. Also, in this embodiment, the capacity of the power battery 40 is larger than the first predetermined capacity, and the power battery 40 is large and can act as a buffer when the engine 10 is operating, replenishing power or absorbing excess power.

[0042] In some further embodiments of the present disclosure, the controller 50 determines a first wheel-side torque threshold at which the hybrid vehicle 1000 enters the parallel mode and a second wheel-side torque threshold at which the hybrid vehicle 1000 exits the parallel mode based on the SOC of the power battery 40 and the vehicle speed of the hybrid vehicle 1000 when the vehicle speed of the hybrid vehicle 1000 is equal to or greater than a predetermined vehicle speed threshold, and controls the hybrid vehicle 1000 to enter the parallel mode when the wheel-side torque request is equal to or greater than the first wheel-side torque threshold and equal to or less than the second wheel-side torque threshold, and controls the engine 10 to operate on the eco line when the wheel-side torque request is greater than the output torque of the engine 10 when operating on the eco line, and controls both the engine 10 and the power battery 40 to respond to the wheel-side torque request. the power battery 40 is controlled to supply power to the drive motor 20, and if the wheel side required torque is smaller than the output torque of the engine 10 when operating on the eco line, the engine 10 is controlled to operate on the eco line in response to the wheel side required torque, and the engine 10 is controlled to drive the drive motor 20 to generate electricity and charge the power battery 40 using excess energy output from the engine 10, and if the wheel side required torque is equal to the output torque of the engine 10 when operating on the eco line, the engine 10 is controlled to operate on the eco line in response to the wheel side required torque alone, and the first wheel side torque threshold is smaller than the second wheel side torque threshold.

[0043] In other words, the operating mode of the hybrid vehicle 1000 is determined based on the wheel side required torque of the hybrid vehicle 1000, the SOC of the power battery 40, and the vehicle speed of the hybrid vehicle 1000, ensuring that the hybrid vehicle 1000 operates in the mode with the lowest equivalent fuel consumption, thereby achieving the goal of energy conservation.

[0044] Specifically, while the hybrid vehicle 1000 is traveling, the controller 50 acquires the vehicle speed of the hybrid vehicle 1000 and compares the vehicle speed with a predetermined vehicle speed threshold (e.g., 65 km / h). When the vehicle speed of the hybrid vehicle 1000 is equal to or higher than the predetermined vehicle speed threshold, the controller 50 can first determine, by a table lookup method, a first wheel-side torque threshold T1 at which the hybrid vehicle 1000 enters the parallel mode and a second wheel-side torque threshold T2 at which the hybrid vehicle 1000 exits the parallel mode, based on the SOC of the power battery 40 and the vehicle speed of the hybrid vehicle 1000. Next, the controller 50 acquires the wheel-side required torque of the hybrid vehicle 1000 and compares the wheel-side required torque with the first wheel-side torque threshold T1 and the second wheel-side torque threshold T2. When the wheel side required torque is equal to or greater than the first wheel side torque threshold T1 and equal to or less than the second wheel side torque threshold T2, the controller 50 controls the clutch C1 to be engaged so that the engine 10 and the wheel side are power-coupled, and the hybrid vehicle 1000 enters the parallel mode.

[0045] After the hybrid vehicle 1000 enters the parallel mode, if the wheel side required torque is greater than the output torque of the engine 10 when operating on the eco line, the controller 50 controls the engine 10 to operate on the eco line and controls the power battery 40 to supply power to the drive motor 20, so that the engine 10 and the power battery 40 both provide the wheel side required torque. At this time, if the hybrid vehicle 1000 enters the parallel power assist mode in the parallel mode and the wheel side required torque is less than the output torque of the engine 10 when operating on the eco line, the controller 50 controls the engine 10 to operate on the eco line. The controller 50 controls the engine 10 to drive the drive motor 20 to generate electricity and uses the excess energy output from the engine 10 to charge the power battery 40 with the drive motor 20, and at this time, the hybrid vehicle 1000 enters a parallel power generation mode in the parallel mode, and if the wheel-side required torque is equal to the output torque of the engine 10 when operating on the eco line, the controller 50 controls the engine 10 to operate on the eco line and solely provide the wheel-side required torque, and at this time, the hybrid vehicle 1000 enters a parallel direct drive mode in the parallel mode.

[0046] Thus, the hybrid vehicle 1000 is controlled to enter the parallel mode based on the wheel side torque required by the hybrid vehicle 1000, the SOC of the power battery 40, and the vehicle speed of the hybrid vehicle 1000, and different methods are used in the parallel mode, so that the engine 10 always operates in the eco zone, thereby achieving the purpose of energy saving and ensuring that the hybrid vehicle 1000 has high economic efficiency. In addition, the hybrid vehicle 1000 can operate in the parallel direct drive mode, whereas the conventional pure range extender type hybrid vehicle lacks the direct drive path of the engine 10, so even in the highly efficient medium-high speed mode of direct drive of the engine 10, it can only generate electricity and then provide it to the drive motor 20 for driving, and the energy needs to be converted by the generator 30, which causes loss during energy conversion, and the power battery 40 frequently operates in a charging and discharging state, which further causes loss during energy conversion. In contrast, the hybrid vehicle 1000 in the present disclosure can operate in the parallel direct drive mode, which effectively avoids the above energy consumption, and further improves the economic efficiency of the hybrid vehicle 1000. As can be seen, in this embodiment, with the current wheel side torque requirement, the current SOC, and the current vehicle speed, operating the hybrid vehicle 1000 in parallel mode saves more energy than operating in series mode and EV mode.

[0047] In some implementations of the present disclosure, the magnitudes of the first wheel-side torque threshold T1 and the second wheel-side torque threshold T2 are positively correlated with the magnitude of the SOC of the power battery 40. That is, the first wheel-side torque threshold T1 and the second wheel-side torque threshold T2 change with the change in the SOC of the power battery 40, thereby ensuring energy saving and realizing power retention of the power battery 40. When the SOC of the power battery 40 is low, the engine 10 is operated as much as possible, and when the SOC of the power battery 40 is high, the vehicle is operated in EV mode as much as possible, ensuring energy saving and improving the NVH effect of the vehicle. In practical application, the first wheel-side torque threshold T1 and the second wheel-side torque threshold T2 can be obtained by a table lookup manner based on the SOC of the power battery 40, as shown in Table 1.

[0048] [Table 1] SOC1 and SOC2 are predetermined values, and SOC1 <SOC2であり、T11<T12<T13であり、T21<T22<T23である。

[0049] In some implementations of the present disclosure, when the hybrid vehicle 1000 operates in parallel mode, the vehicle speed at which the engine 10 is involved in operation is inversely correlated with the magnitude of the SOC of the power battery 40. That is, in parallel mode, the vehicle speed at which the engine 10 is involved in operation changes with changes in the SOC of the power battery 40 to reduce the length of time in parallel mode as much as possible, and discharge the power battery 40 as much as possible to power the traction motor 20, i.e., use as much electricity as possible, i.e., operate in EV mode as much as possible. In practical application, the vehicle speed V at which the engine 10 is involved in operation can be obtained by a table lookup method based on the SOC of the power battery 40, as shown in Table 2.

[0050] [Table 2] SOC1 and SOC2 are predetermined values, and SOC1 <SOC2であり、V3<V2<V1である。

[0051] In some embodiments of the present disclosure, the controller 50 controls the engine 10 to stop operating when the wheel-side required torque is less than a first wheel-side torque threshold T1, and controls the power battery 40 to supply power to the drive motor 20 so that the power battery 40 responds to the wheel-side required torque.

[0052] It should be noted that this method is the EV mode of the hybrid vehicle 1000, i.e., the pure EV mode, and when the hybrid vehicle 1000 runs in the EV mode, the engine 10 does not need to be involved in the operation, and at this time, the fuel consumption rate is zero, and the efficiency of the hybrid vehicle 1000 can reach 90% or more, and is highly economical. Specifically, when the wheel side required torque is smaller than the first wheel side torque threshold T1, the controller 50 controls the clutch C1 to be disconnected so as to cut off the power output between the engine 10 and the wheel side, controls the engine 10 and the generator 30 to stop operating, controls the power battery 40 to supply power to the drive motor 20, and provides the wheel side required torque by the drive motor 20, and at this time, the hybrid vehicle 1000 enters the EV mode, i.e., the pure EV mode. As can be seen, in this embodiment, with the current wheel side required torque, the current SOC, and the current vehicle speed, it is more energy-saving when the hybrid vehicle 1000 operates in the EV mode, so the operation mode of the vehicle is switched from the parallel mode to the EV mode.

[0053] In this way, by controlling hybrid vehicle 1000 to enter EV mode based on the wheel side torque required by hybrid vehicle 1000, the SOC of power battery 40, and the vehicle speed of hybrid vehicle 1000, the efficiency is high in EV mode, so that the goal of energy saving can be achieved and it can be ensured that hybrid vehicle 1000 is highly economical.

[0054] In some embodiments of the present disclosure, the controller 50 is further configured to: control the hybrid vehicle 1000 to enter a series mode when the wheel side torque required is greater than a second wheel side torque threshold T2; determine the wheel side power required based on the wheel side torque required and the vehicle speed; drive the generator 30 to generate electricity based on a predetermined power when operating at the optimal eco point of the engine 10, and control the engine 10 to operate at the optimal eco point with the predetermined power so as to output power to the wheel side by the traction motor 20; charge the power battery 40 by the generator 30 using the excess power when the generated power of the generator 30 is greater than the wheel side required power; and control the engine 10 to increase the output power of the engine 10 when the generated power of the generator 30 is less than the wheel side required power, and control the engine 10 to operate at the eco line of the engine 10 in response to the wheel side required power.

[0055] Specifically, when the wheel side required torque is greater than the second wheel side torque threshold T2, the controller 50 cuts off the power output between the engine 10 and the wheel side, controls the clutch C1 to be disengaged so that the engine 10 drives the generator 30 to generate electricity, and outputs power to the wheel side by the drive motor 20 so that the hybrid vehicle 1000 enters the series mode. In the series mode, the controller 50 controls the engine 10 to operate at an optimal eco point with a predetermined power (e.g., 25 kW), obtains the wheel side required torque and the vehicle speed, and determines the wheel side required power based on the wheel side required torque and the vehicle speed, and compares the wheel side required power with the generated power of the generator 30. If the generated power of the generator 30 is greater than the power required by the wheel side, the controller 50 uses the excess power to charge the power battery 40 with the generator 30, and if the generated power of the generator 30 is less than the power required by the wheel side, the controller 50 controls the engine 10 to increase its output power and also controls the engine 10 to operate on its eco line so as to provide the power required by the wheel side.

[0056] Thus, based on the wheel side required torque of the hybrid vehicle 1000, the SOC of the power battery 40, and the vehicle speed of the hybrid vehicle 1000, the hybrid vehicle 1000 is controlled to enter the series mode, and by using different methods in the series mode, the engine 10 always operates in the eco zone, thereby achieving the purpose of energy saving and ensuring high economic efficiency of the hybrid vehicle 1000. As can be seen, in this embodiment, with the current wheel side required torque, the current SOC, and the current vehicle speed, if the hybrid vehicle 1000 operates in the series mode, it is more energy saving, so the operation mode of the vehicle is switched from the parallel mode to the series mode, and the engine 10 always operates in the eco line, specifically, from the eco line of the parallel mode to the eco line of the series mode.

[0057] In some embodiments of the present disclosure, the controller 50 is further configured to, when the generated power of the generator 30 is less than the wheel side required power, check whether the current SOC of the power battery 40 is less than a second predetermined value (e.g., 10%, 15%, etc.), and if so, control the output power of the engine 10 to respond to the wheel side required power, and to control the output power of the engine 10 to continue to increase so as to charge the power battery 40 by the generator 30.

[0058] In other words, when the generated power of the generator 30 is smaller than the power required by the wheels and the current SOC of the power battery 40 is smaller than a second predetermined value, i.e., when the SOC of the power battery 40 is extremely low, the engine 10 increases the output power on the premise that the driving requirements are met, that is, the operating point of the engine 10 moves in the direction of increasing the output torque on the eco line, and some of the energy is transmitted to the power battery 40 to charge the power battery 40, so that the engine 10 operates in energy saving mode and power is replenished to the power battery 40.

[0059] The thermal efficiency is highest when the engine 10 operates at the optimal eco point, and as shown in Fig. 2, when the output power of the engine 10 is 25 kW, the corresponding thermal efficiency is 43.04%. Therefore, after the engine 10 starts, if the wheel side required power is smaller than the generated power of the generator 30, the engine 10 drives the generator 30 to generate power at the optimal eco point, and then drives the driving motor 20, after which the excess energy enters the power battery 40. On the other hand, if the wheel side required power is larger than the generated power of the generator 30, the engine 10 follows the wheel side required power at a power exceeding the power corresponding to the optimal eco point and drives at the high efficiency eco line of the engine 10, that is, the engine 10 operates at the eco line of the engine 10, but outputs more power. In some embodiments of the present disclosure, when the wheel side power requirement is greater than the power generated by the generator 30 and the SOC of the power battery 40 drops to a certain value, the engine 10 continues to increase the power to meet the power requirement and some energy enters the power battery 40 to charge the power battery 40, that is, at this time, the engine 10 increases the output power on the premise of meeting the driving requirement to supply some energy to the power battery 40, and when the SOC of the power battery 40 rises to a certain value, the controller 50 controls the engine 10 to stop and enters the EV mode. In this manner, as shown in FIG. 3, the proportion of pure EV driving of the hybrid vehicle 1000 in the power shortage mode can reach 81%, so that the hybrid vehicle 1000 is guaranteed to have high economic efficiency, and a typical power shortage mode is an urban power shortage mode, which not only includes frequent starting and stopping of the vehicle and following traffic jams, but also often has a medium to low vehicle speed with strict NVH restrictions.

[0060] In some embodiments of the present disclosure, the controller 50 is further configured to: determine a third wheel-side torque threshold T3 at which the hybrid vehicle 1000 enters the series mode based on the SOC of the power battery 40 and the vehicle speed when the vehicle speed of the hybrid vehicle 1000 is lower than a predetermined vehicle speed threshold; and control the hybrid vehicle 1000 to enter the series mode when the wheel-side torque required is equal to or higher than the third wheel-side torque threshold T3; determine a wheel-side power required based on the wheel-side torque required and the vehicle speed; drive the generator 30 to generate electricity based on a predetermined power when operating at the optimal eco point of the engine 10, and control the engine 10 to operate at the optimal eco point with the predetermined power so as to output power to the wheel side by the traction motor 20; charge the power battery 40 using the excess power by the generator 30 when the generated power of the generator 30 is greater than the wheel-side required power; and control the engine 10 to increase the output power of the engine 10 when the generated power of the generator 30 is smaller than the wheel-side required power, and control the engine 10 to operate at the eco line of the engine 10 in response to the wheel-side power required.

[0061] In some embodiments of the present disclosure, the controller 50 controls the engine 10 to stop operation when the wheel side torque requirement is less than a third wheel side torque threshold, and controls the power battery 40 to power the traction motor 20 so as to respond to the wheel side torque requirement by the power battery 40. As can be seen, in this embodiment, with the current wheel side torque requirement, the current SOC, and the current vehicle speed, operating the hybrid vehicle 1000 in the EV mode is more energy-efficient, so the vehicle operation mode is switched from the series mode to the EV mode.

[0062] In other words, when the vehicle speed of the hybrid vehicle 1000 is low, for example, lower than 65 km / h, the hybrid vehicle 1000 can be controlled to enter the series mode or the EV mode based on the SOC of the power battery 40 and the vehicle speed; that is, when the speed is low, it is limited by the hardware and cannot enter the parallel mode. At this time, it is sufficient to compare the equivalent energy consumption in the series mode and the EV mode, which reduces the amount of calculation of the system, reduces the requirements for the processing speed of the controller 50, allows the processing speed to be faster, reduces the application of high-speed processing chips, and reduces costs.

[0063] Specifically, when the vehicle speed of the hybrid vehicle 1000 is lower than a predetermined vehicle speed threshold (e.g., 65 km / h), a third wheel-side torque threshold T3 at which the hybrid vehicle 1000 enters the series mode can be determined by a table lookup method based on the SOC of the power battery 40 and the vehicle speed, and the third wheel-side torque threshold T3 can be compared with the wheel-side required torque.

[0064] When the wheel side required torque is equal to or greater than the third wheel side torque threshold T3, the controller 50 controls the hybrid vehicle 1000 to enter a series mode. In the series mode, the controller 50 controls the engine 10 to operate at an optimal eco point with a predetermined power (e.g., 25 kW), and obtains the wheel side required torque and the vehicle speed, and determines the wheel side required power based on the wheel side required torque and the vehicle speed. If the generated power of the generator 30 is greater than the wheel side required power, the controller 50 uses the excess power to charge the power battery 40 via the generator 30; if the generated power of the generator 30 is less than the wheel side required power, the controller 50 controls the engine 10 to increase its output power and controls the engine 10 to operate on its eco line to provide the wheel side required power; in some embodiments of the present disclosure, if the generated power of the generator 30 is less than the wheel side required power and the current SOC of the power battery 40 is less than a second predetermined value, the engine 10 increases its output power on the premise of meeting the driving requirements and transmits some of the energy to the power battery 40 to replenish the power of the power battery 40.

[0065] If the wheel-side required torque is less than the third wheel-side torque threshold T3, the controller 50 controls the engine 10 to stop operation and controls the power battery 40 to supply power to the drive motor 20 so as to provide the wheel-side required torque from the power battery 40, and at this time the hybrid vehicle 1000 enters EV mode.

[0066] Thus, the hybrid vehicle 1000 is controlled to enter the series mode based on the wheel side torque requirement of the hybrid vehicle 1000, the SOC of the power battery 40, and the vehicle speed of the hybrid vehicle 1000, and different methods are used in the series mode, so that the engine 10 always operates in the eco zone, thereby achieving the purpose of energy saving and ensuring that the hybrid vehicle 1000 has high economic efficiency. In some implementations of the present disclosure, the magnitude of the third wheel side torque threshold T3 is positively correlated with the magnitude of the SOC of the power battery 40. That is, the third wheel side torque threshold T3 changes with the change in the SOC of the power battery 40 to reduce the time length in the series mode as much as possible, and discharge the power battery 40 as much as possible to supply power to the traction motor 20, that is, use electricity as much as possible, that is, mainly use the EV mode as much as possible. In practical application, the third wheel side torque threshold T3 can be obtained by a table lookup method based on the SOC of the power battery 40, as shown in Table 3.

[0067] [Table 3] SOC1 and SOC2 are predetermined values, and SOC1 <SOC2であり、T31<T32<T33である。

[0068] In some embodiments of the present disclosure, as shown in FIG. 4 , when the hybrid vehicle 1000 operates in the series mode, the controller 50 is further configured to control the engine 10 to operate on a first eco line if the SOC of the power battery 40 is in a first predetermined interval, and to control the engine 10 to operate on a second eco line if the SOC of the power battery 40 is in a second predetermined interval, where an upper limit of the second predetermined interval is equal to or lower than a lower limit of the first predetermined interval, and the first eco line is an optimal eco line for the series mode, and at the same rotation speed, the output torque of the engine 10 operating on the second eco line is equal to or higher than the output torque of the engine 10 operating on the first eco line, and in this embodiment, the second eco line may be approximately equal to the external characteristic line of the engine 10, or may be set to be between the first eco line and the external characteristic line of the engine 10. The first predetermined section may be a section in which the SOC of the power battery 40 is 17% or more, and the second predetermined section may be a section in which the SOC of the power battery 40 is less than 17%.

[0069] In some embodiments of the present disclosure, as shown in FIG. 5 , when the hybrid vehicle 1000 operates in the parallel mode, the controller 50 is further configured to: control the engine 10 to operate on the third ecoline if the SOC of the power battery 40 is in a third predetermined interval; control the engine 10 to operate on the fourth ecoline if the SOC of the power battery 40 is in a fourth predetermined interval; and control the engine 10 to operate on the fifth ecoline if the SOC of the power battery 40 is in a fifth predetermined interval, wherein an upper limit of the fifth predetermined interval is equal to or lower than a lower limit of the fourth predetermined interval, and an upper limit of the fourth predetermined interval is equal to or lower than a lower limit of the third predetermined interval, the third ecoline is an optimal ecoline in the parallel mode, the fifth ecoline approximately coincides with the external characteristic line of the engine 10, and the fourth ecoline is between the fifth ecoline and the third ecoline. The third predetermined section may be a section where the SOC of the power battery 40 is 25% or more, the fourth predetermined section may be a section where the SOC of the power battery 40 is greater than 15% and less than 25%, and the fifth predetermined section may be a section where the SOC of the power battery 40 is 15% or less, that is, the optimal operating mode of the engine 10 is not to operate in an eco zone between eco lines, but to always operate in an eco line, and as mentioned above, the eco zone of the present disclosure may be two eco lines in series mode or three eco lines in parallel mode in an eco zone, which is of course not limited to this and will be described as an example in this specification. In other words, because the eco line on which engine 10 operates can be moved, when the SOC of power battery 40 is low, hybrid vehicle 1000 adjusts the eco line on which engine 10 operates and increases the proportion of engine 10 involved in driving and the output torque, thereby enabling power conservation for power battery 40. The eco lines of engine 10 in parallel mode and series mode are different, thereby achieving a reduction in overall fuel consumption of hybrid vehicle 1000.

[0070] As described above, the hybrid vehicle 1000 according to an embodiment of the present disclosure has a series mode and a parallel mode set, and can achieve highly efficient operation of the engine 10 over the entire range of low speed and medium to high speed modes. In the medium to high speed mode, it is possible to check whether the engine 10 will operate in parallel mode or series mode based on the driving parameters, and in the low speed mode, it is possible to check the timing at which the engine 10 will enter series mode based on the driving parameters, thereby increasing the probability that the engine 10 will operate in the optimal eco line and ensuring that the engine 10 always operates in the eco zone, thereby achieving energy savings.

[0071] In some embodiments of the present disclosure, the controller 50 is further configured to determine the SOC of the power battery 40, and when the SOC of the power battery 40 is less than a third predetermined value, control the hybrid vehicle 1000 to operate in a series mode or a parallel mode based on the SOC of the power battery 40, the vehicle speed, and the wheel side torque request, and control the engine 10 to operate in an eco zone. That is, when the SOC of the power battery 40 is less than a third predetermined value (e.g., 25%), control the hybrid vehicle 1000 to enter a series mode or a parallel mode based on the SOC of the power battery 40, the vehicle speed, and the wheel side torque request, and when the hybrid vehicle 1000 operates in the series mode or the parallel mode, control the engine 10 to operate in an eco zone, and when the hybrid vehicle 1000 operates in the EV mode, avoid a too fast power reduction in the case of a power shortage mode and realize power conservation of the power battery 40.

[0072] As a specific example, the controller 50 may be configured to control the hybrid vehicle 1000 according to a control logic shown in FIG. 6a to FIG. 6b, and specifically, the control logic may include the following steps S101 to S126.

[0073] In step S101, determine whether to manually select to enter EV mode or HEV mode (hybrid mode). If yes, execute step S102; if not, continue to run in the current mode.

[0074] In step S102, it is determined whether the EV mode is selected. If so, step S103 is executed, and if not, step S105 is executed.

[0075] In step S103, the EV mode is entered and operation is performed.

[0076] In step S104, it is determined whether the SOC of the power battery 40 is currently in a power shortage mode. If so, execute step S105; if not, return to step S103.

[0077] In step S105, the vehicle operates in the HEV mode.

[0078] In step S106, it is determined whether or not the vehicle speed is greater than or equal to 65 km / h. If so, step S107 is executed, and if not, step S123 is executed.

[0079] In step S107, a first wheel-side torque threshold T1 for entering the parallel mode and a second wheel-side torque threshold T2 for exiting the parallel mode are obtained by table lookup based on the SOC of the power battery 40 and the vehicle speed.

[0080] In step S108, it is determined whether the wheel side required torque T is smaller than T1. If so, step S109 is executed, and if not, step S110 is executed.

[0081] In step S109, the EV mode is entered and operation is performed.

[0082] In step S110, it is determined whether the wheel side required torque T is greater than T2. ​​If so, step S111 is executed, and if not, step S119 is executed.

[0083] In step S111, the serial mode is entered and the device operates.

[0084] In step S112, the engine 10 is operated at a constant output power to maintain high efficiency.

[0085] In step S113, it is determined whether the electric power of the generator 30 is greater than the wheel-side required electric power. If so, step S114 is executed, and if not, step S115 is executed.

[0086] In step S114, the generator 30 is controlled so as to charge the power battery 40 with the excess power.

[0087] In step S115, the output power of the engine 10 is increased and is output based on the wheel side requested power, and the engine 10 operates on the eco line.

[0088] In step S116, determine whether the SOC of the power battery 40 is extremely low (e.g., the SOC of the power battery 40 is lower than a second predetermined value). If so, execute step S118; if not, execute step S117.

[0089] In step S117, power is generated based on the wheel side required power.

[0090] In step S118, engine 10 continues to increase its output power but still operates at the eco line.

[0091] In step S119, the parallel mode is entered and operation is performed.

[0092] In step S120, it is determined whether or not the wheel side required torque T is greater than the output torque of the eco line of the engine 10. If so, step S121 is executed, and if not, step S122 is executed.

[0093] In step S121, in the parallel power assist mode, the engine 10 always operates on the eco line, and the power battery 40 drives the drive motor 20 to assist in making up for the lack of energy.

[0094] In step S122, power is generated in parallel so that the engine 10 always operates on the eco line, and excess energy is used to charge the power battery 40 by the drive motor 20.

[0095] In step S123, a third wheel-side torque threshold T3 for entering the series mode is obtained by table lookup based on the SOC of the power battery 40 and the vehicle speed.

[0096] In step S124, it is determined whether the wheel side required torque T is smaller than T3. If so, step S125 is executed, and if not, step S126 is executed.

[0097] In step S125, the vehicle enters and operates in the EV mode.

[0098] In step S126, the serial mode is entered for operation.

[0099] In some embodiments of the present disclosure, Fig. 7 is a schematic diagram showing a corresponding control policy. As can be seen from Fig. 7, when the SOC of the power battery 40 is high (e.g., SOC≧70%), the vehicle often runs on pure electricity, that is, the ratio of the EV mode operation region is higher than the ratio of the series mode operation region, and at medium and high speeds, the engine 10 is mainly driven directly, and the engine 10 operates at an optimal eco line, and is assisted by the traction motor 20 to meet the wheel side requirements, that is, the parallel power assist mode is entered, and only when a large amount of power is required, the series power generation mode can be entered to meet the wheel side requirements.

[0100] 7, as the SOC of the power battery 40 decreases, the EV mode operating range decreases and the series mode operating range increases, and after driving at medium to high speed and being directly driven by the engine 10, the assist torque of the drive motor 20 decreases, mitigating the rate at which the SOC of the power battery 40 decreases and realizing the power battery 40 to maintain electric power. In the parallel mode, when the speed involved in the operation of the engine 10 is higher than the SOC of the power battery 40, the involved speed is smaller and closer to the predetermined vehicle speed threshold.

[0101] When the SOC of the power battery 40 is extremely low (for example, SOC≦18%), in order to improve the power retention of the vehicle's power battery 40, the vehicle does not run on pure electricity, but instead operates in series at low speed, and drives the engine 10 to generate electricity in series mode to generate more power to replenish the power battery 40. As a result, the direct drive range of the engine 10 at high speed is reduced, and after the engine 10 is directly driven, more power is generated to replenish the power battery 40.

[0102] Thus, the SOC of the power battery 40 is identified, and in the process of the SOC constantly decreasing, the priority of the power retention performance of the vehicle is constantly improved, so that the EV mode operation area is constantly reduced. During series driving, based on the SOC of the different power batteries 40, it is divided into series power tracking (when the SOC of the power battery 40 is low) and series constant power (when the SOC of the power battery 40 is high), in the case of series power tracking, the operating point of the engine 10 operates according to the eco line of the engine 10, and when the SOC of the power battery 40 is extremely low, the power output from the engine 10 responds to the wheel side required power and charges the power battery 40, and in the case of series constant power, the engine 10 operates at a high efficiency eco point (e.g., 25 kW), and when driving only by the engine 10 is not satisfactory, the power battery 40 outputs a part of the energy, and the power battery 40 and the engine 10 drive the drive motor 20 together. As can be understood, 25 KW is an exemplary eco point in this embodiment.

[0103] For example, when the SOC is high and the vehicle speed is high, the wheel side requirements are small, and at this time the parallel mode is mainly used, i.e. the engine 10 is mainly driven directly. Using this method is economical and consumes less energy. For example, in a test, the fuel consumption equivalent to the power when using the EV mode alone is about 1.5 times that when the engine 10 is operated in the eco zone, and the NVH performance is excellent. For example, when the vehicle speed is 100 km / h, the engine 10 rotation speed is about 2500 rpm in the parallel mode, and when the series generation mode is selected, the engine 10 rotation speed is greater than 3000 rpm, and the power retention performance is excellent. For example, in this mode, the power battery 40 does not discharge to the outside, and the SOC of the power battery 40 hardly decreases. In contrast, when the EV mode is selected, the power battery 40 discharges to the outside, and the SOC power decrease of the power battery 40 is fast. In addition, since the power battery 40 has a large capacity, a large discharge power, and can run long distances on pure electricity and for long periods of time on pure electricity, the vehicle has excellent NVH performance, and the engine 10 and drive motor 20 operate in high-efficiency sections, resulting in low vehicle energy consumption.

[0104] The EV mode is mainly used when the SOC of the power battery 40 is near the equilibrium point or when the vehicle is in low speed or urban congestion mode. This method is economical; for example, the efficiency of the drive motor 20 is high in low speed mode. In contrast, when the series power generation mode is selected, it is unavoidable that the engine 10 operates in a low efficiency zone, and at this time, the power generation efficiency of the engine 10 is low. In addition, the EV mode is excellent in NVH performance; for example, there is no startup noise of the engine 10 in this mode, and it is quiet. In contrast, when the series mode is selected, the engine 10 rotation speed is 1400 rpm to 1600 rpm, and the experience is somewhat inferior.

[0105] When the SOC is low and the torque required from the wheel side is large (for example, when accelerating with a large accelerator or when the driver's request is large), the series mode is mainly used. When this method is used, the driving performance is excellent; for example, when the discharge capacity of the power battery 40 is insufficient, the engine 10 has strong generating power and can meet the driver's request to accelerate and overtake, and the power retention performance is excellent; for example, in this mode, when the discharge capacity of the power battery 40 is insufficient, the engine 10 can generate power according to the driver's request. In contrast, when the parallel power assist mode is selected, the engine 10 is directly connected to the wheel side, so the engine 10 operates in the eco zone and cannot meet the driving request, and it is necessary to replenish a large amount of power to the power battery 40, resulting in poor power retention performance.

[0106] As a result, when the vehicle is traveling at medium to low speeds, the hybrid vehicle 1000 mainly uses the EV mode and the series mode, and when the vehicle is traveling at high speeds, the hybrid vehicle 1000 mainly uses the direct drive of the engine 10, and in the series mode, the engine 10 operates at the eco line to ensure fuel economy, and when the power battery 40 is in an extremely low SOC state, the engine 10 operates at the second eco line to improve power retention, and in the case of direct drive of the engine 10, when the SOC is high, the engine 10 operates at the eco line, and as the SOC decreases, the eco line on which the engine 10 operates gradually shifts toward the external characteristic line to improve power retention. As a result, the energy consumption, power performance, and NVH of the hybrid vehicle 10 can better meet the needs of users.

[0107] The control core of the present disclosure is mainly for electric drive, and as shown in Fig. 8a-8b, the high-efficiency operating region of the drive motor 20 covers almost the entire rotation speed and torque region, and the direct drive of the engine 10 is assisted, and as shown in Fig. 9, the engine 10 is always operated in the optimal eco line, thereby improving the fuel economy of the vehicle. In tests, the ratio of the region where the efficiency of the drive motor 20 exceeds 90% exceeds 90.7%, the motor drive is in the high efficiency region for a long time, the engine 10 is in a high efficiency section of 38% or more for 70% of the time during operation, and the capacity of the power battery 40 is 5 kWh or more, so that the ratio of the EV driving mode can be guaranteed even when the battery is not fully charged, and the engine 10 can be operated in the high efficiency section, and when the engine 10 operates in the eco zone, if the output power is greater than the power required by the vehicle, the battery absorbs the excess energy, thereby extending the time that the vehicle operates in the electric drive mode.

[0108] In some embodiments of the present disclosure, as shown in FIG. 1a and FIG. 10, the aforementioned hybrid system 100 further includes a dual electric control module 60, which is connected to the drive motor 20 and the generator 30, respectively, and supplies power to the drive motor 20 based on the AC current output from the generator 30; the power battery 40 is connected to the dual electric control module 60, and the power battery 40 supplies power to the drive motor 20 by the dual electric control module 60, or is charged by the dual electric control module 60 based on the AC current output from the generator 30 or the drive motor 20; the maximum operating power of the generator 30 is equal to or greater than a first predetermined power, the maximum operating power of the engine 10 is equal to or greater than a second predetermined power, the second predetermined power is equal to or greater than the first predetermined power, and the difference between the second predetermined power and the first predetermined power is less than 5% to 10% of the second predetermined power.

[0109] In some implementations of the present disclosure, the capacity of the power battery 40 is equal to or greater than a first predetermined capacity, for example, the first predetermined capacity is 5 kWh to 25 kWh. The first predetermined power may be set to 70 kW, and the second predetermined power may be set to 81 kW.

[0110] In the present disclosure, since the capacity of the power battery 40 is large, the hybrid vehicle 1000 operates in EV mode for 80% of the operating time, and since the capacity of the power battery 40 is large, the operation of the engine 10 can be balanced by charging and discharging, so that when the engine 10 is in an operating state, it can always operate to drive or generate electricity with high efficiency (specifically, see above). And since the generator 30 is large and the generated power is accordingly large, power can be quickly replenished, and the time to increase the SOC of the power battery 40 from 20% to 25% is about 5 minutes, that is, one SOC requires about 1 minute when generating power on site. And since the difference in maximum operating power between the generator 30 and the engine 10 is not large, the generator 30 can fully utilize the active power of the engine 10 and avoid energy waste. With the above configuration, the engine 10 becomes the energy source, the generator 30 becomes the pipes through which the energy flows, and the battery becomes the reservoir, with no bottlenecks in the energy flow between the source, the pipes, and the reservoir; that is, the parameters of the engine 10, the generator 30, and the battery work together to achieve highly efficient and rational use of energy.

[0111] In some embodiments of the present disclosure, as shown in FIG. 10 , the dual electric control module 60 includes a first inverter 61, a second inverter 62 and a DC / DC 63, the AC end of the first inverter 61 is connected to the traction motor 20, the DC end of the first inverter 61 is connected to the DC end of the second inverter 62 and the first DC end of the DC / DC 63, respectively, the AC end of the second inverter 62 is connected to the generator 30, and the second DC end of the DC / DC 63 is connected to the power battery 40.

[0112] In some implementations of the present disclosure, the maximum operating power of the DC / DC 63 is greater than the third predetermined power, which is greater than the second predetermined power, and may be set to, for example, 90 kW. This allows the power battery 40 to fully utilize its capacity, thereby outputting the maximum power of the power battery 40 to the drive motor 20.

[0113] In some implementations of the present disclosure, the difference between the third predetermined power and the second predetermined power is less than 5% to 10% of the third predetermined power. In this way, regardless of the SOC of the power battery 40, the driving motor 20 is in a high efficiency section for most of the time due to the power generated by the engine 10, and the third predetermined power is close to the maximum operating power of the driving motor 20, so that it is effectively avoided to waste power by driving a light load with a large power motor.

[0114] Hereinafter, the operation states of the dual electric control module 60 when the hybrid vehicle 1000 is in different operation modes will be described with reference to Fig. 10. In some embodiments of the present disclosure, as shown in Fig. 10, when the power output between the engine 10 and the wheel side is cut off and the generator 3010 is driven to generate electricity, the hybrid system 100 enters a series mode, and the AC current output from the generator 30 is converted to DC current by the second inverter 62, and the DC current is converted to AC current by the first inverter 61 and supplied to the traction motor 20, so that the traction motor 20 performs a driving operation; or the AC current output from the generator 30 is converted to DC current by the second inverter 62, and the DC current is converted to AC current by the first inverter 61. The second inverter 62 converts the AC current output from the generator 30 into a DC current and supplies it to the drive motor 20, and the DC current output from the power battery 40 is converted by the DC / DC 63 and then the first inverter 61 converts the DC current into an AC current and supplies it to the drive motor 20, thereby causing the drive motor 20 to perform a driving operation. Alternatively, the second inverter 62 converts the AC current output from the generator 30 into a DC current and the first inverter 61 converts the DC current into an AC current and supplies it to the drive motor 20, thereby causing the drive motor 20 to perform a driving operation, and the DC current is converted by the DC / DC 63 before charging the power battery 40.

[0115] In some embodiments of the present disclosure, when the engine 10 and the generator 30 are not operating and the power battery 40 supplies power to the drive motor 20, the hybrid system 100 enters EV mode, and the direct current output from the power battery 40 passes through the DC / DC 63, after which the first inverter 61 converts the direct current to alternating current and supplies it to the drive motor 20, thereby causing the drive motor 20 to perform driving operation.

[0116] In some embodiments of the present disclosure, when the engine 10 and the wheel side are power-coupled, the generator 30 is idling, and the engine 10 drives the drive motor 20 to generate electricity, the hybrid system 100 enters a parallel power generation mode, and the AC current output from the drive motor 20 is converted to DC current by the first inverter 61, and the DC current is then converted by the DC / DC 63 before charging the power battery 40.

[0117] This allows power to be generated by the drive motor 20 during parallel power generation, resulting in greater power for the drive motor 20, faster power replenishment, and smaller losses due to idling of the generator 30 than losses due to idling of the drive motor 20, resulting in energy savings.

[0118] In some embodiments of the present disclosure, when the engine 10 and the wheel side are power-coupled, the generator 30 is spinning, and the power battery 40 is supplying power to the drive motor 20, the hybrid system 100 enters a parallel power assist mode, and the direct current output from the power battery 40 is converted by the DC / DC 63, and then the direct current is converted to alternating current by the first inverter 61 and supplied to the drive motor 20, causing the drive motor 20 to perform driving operation, and the engine 10 is involved in the driving operation by outputting power to the wheel side.

[0119] The hybrid system 100 according to an embodiment of the present disclosure allows the hybrid vehicle 1000 to be primarily driven by electricity with fuel-powered driving as an auxiliary, and by comprehensively taking into consideration the current vehicle speed, actual required torque, SOC of the power battery 40, and the high-efficiency sections of the engine 10 and the drive motor 20, driving in a high-efficiency mode is prioritized, and the vehicle's power performance and power retention performance are combined to switch modes, so that the energy consumption, power performance, and NVH of the hybrid vehicle 1000 can better meet the user's requirements.

[0120] FIG. 11 is a schematic diagram of a hybrid vehicle 1000 according to one embodiment of the present disclosure. As shown in FIG. 11, the hybrid vehicle 1000 includes the hybrid system 100 described above.

[0121] In the hybrid vehicle 1000 according to the embodiment of the present disclosure, the aforementioned hybrid system 100 enables the hybrid vehicle 1000 to operate in an operating mode with the lowest equivalent fuel efficiency based on the driving parameters, and consumes less energy, thereby effectively improving the economic efficiency of the hybrid vehicle 1000 and meeting the user's expectations for use.

[0122] Fig. 12 is a flowchart of a control method for a hybrid vehicle 1000 according to an embodiment of the present disclosure. As shown in Fig. 1a, the hybrid vehicle 1000 includes an engine 10 that selectively outputs power to the wheels, a drive motor 20 that outputs power to the wheels, a generator 30 that is connected to the engine 10 and driven by the engine 10 to generate power, and a power battery 40 that supplies power to the drive motor 20, is charged based on an AC current output from the generator 30 or the drive motor 20, and has a capacity equal to or greater than a first predetermined capacity.

[0123] 12, the control method for hybrid vehicle 1000 includes the following steps S201 to S203. In step S201, the driving parameters of hybrid vehicle 1000 are acquired.

[0124] In step S202, the engine 10, the drive motor 20, and the generator 30 are controlled based on the driving parameters, and charging and discharging of the power battery 40 is controlled, so that the engine 10 operates in the eco zone.

[0125] In step S203, the equivalent fuel consumption of the hybrid vehicle 1000 in the series mode, parallel mode, and EV mode is compared, and the operation mode with the lowest equivalent fuel consumption is selected as the current operation mode of the hybrid vehicle 1000.

[0126] In some embodiments of the present disclosure, when engine 10 operates in an eco zone, if the SOC of power battery 40 is greater than or equal to a first predetermined value, engine 10 is controlled to operate at the optimal eco line, or if the SOC of power battery 40 is less than the first predetermined value and the output power of engine 10 is greater than or equal to the wheel side required power, engine 10 is controlled to operate at the optimal eco line, and the magnitude of the first predetermined value is inversely correlated with the magnitude of the first predetermined capacity.

[0127] In some embodiments of the present disclosure, when the hybrid vehicle 1000 is in series mode, the engine 10 charges the power battery 40 through the generator 30, and when the hybrid vehicle 1000 is in parallel mode, the engine 10 charges the power battery 40 through the traction motor 20.

[0128] In some embodiments of the present disclosure, the driving parameters include at least one of a wheel-side torque demand, a SOC of the power battery 40, and a vehicle speed of the hybrid vehicle 1000.

[0129] In some embodiments of the present disclosure, when the hybrid vehicle 1000 is in the parallel mode, the step of controlling the engine 10, the traction motor 20, and the generator 30 based on the driving parameters includes the steps of: determining a wheel-side required torque; if the wheel-side required torque is smaller than the output torque of the engine 10 when operating on the eco line, controlling the engine 10 to operate on the eco line in response to the wheel-side required torque, and controlling the engine 10 to drive the traction motor 20 to generate electricity so that the power battery 40 is charged by the traction motor 20 using excess energy output from the engine 10; and if the wheel-side required torque is greater than the output torque of the engine 10 when operating on the eco line, controlling the engine 10 to operate on the eco line, and controlling the power battery 40 to supply power to the traction motor 20 so that both the power battery 40 and the engine 10 respond to the wheel-side required torque.

[0130] In some embodiments of the present disclosure, when the hybrid vehicle 1000 is in series mode, the step of controlling the engine 10, the traction motor 20, and the generator 30 based on the driving parameters includes the steps of determining a wheel side required power based on a wheel side required torque and vehicle speed, controlling the engine 10 to operate on an eco line so as to drive the generator 30 to generate electricity based on the output torque of the engine 10 when operating on an eco line and to output power to the wheel side by the traction motor 20, if the generated power of the generator 30 is greater than the wheel side required power, charging the power battery 40 with the generator 30 using the excess power, and if the generated power of the generator 30 is less than the wheel side required power, controlling the power battery 40 to supply power to the traction motor 20 so that both the engine 10 and the power battery 40 respond to the wheel side required power.

[0131] In some embodiments of the present disclosure, the step of controlling the engine 10, the drive motor 20, and the generator 30 based on the driving parameters includes a step of determining a first wheel side torque threshold at which the hybrid vehicle 1000 enters the parallel mode and a second wheel side torque threshold at which the hybrid vehicle 1000 exits the parallel mode based on the SOC of the power battery 40 and the vehicle speed of the hybrid vehicle 1000 when the vehicle speed of the hybrid vehicle 1000 is equal to or higher than a predetermined vehicle speed threshold, and controlling the hybrid vehicle 1000 to enter the parallel mode when the wheel side required torque is equal to or higher than the first wheel side torque threshold and equal to or lower than the second wheel side torque threshold; and controlling the engine 10 to operate on the eco line and, if the wheel side required torque is greater than the output torque when the engine 10 operates on the eco line, the step of controlling the power battery 40 to supply power to the drive motor 20 so that both the power battery 40 and the power battery 40 respond to the wheel-side required torque; if the wheel-side required torque is smaller than the output torque of the engine 10 when it operates on the eco line, controlling the engine 10 to operate on the eco line so as to respond to the wheel-side required torque, and controlling the engine 10 to drive the drive motor 20 to generate electricity so that the power battery 40 is charged by the drive motor 20 using excess energy output from the engine 10; and if the wheel-side required torque is equal to the output torque of the engine 10 when it operates on the eco line, controlling the engine 10 to operate on the eco line so as to respond solely to the wheel-side required torque.

[0132] In some embodiments of the present disclosure, the step of controlling the engine 10, the traction motor 20 and the generator 30 based on the driving parameters further includes the steps of controlling the engine 10 to stop operation when the wheel-side torque requirement is less than a first wheel-side torque threshold, and controlling the power battery 40 to supply power to the traction motor 20 so that the power battery 40 responds to the wheel-side torque requirement.

[0133] In some embodiments of the present disclosure, the step of controlling the engine 10, the traction motor 20, and the generator 30 based on the driving parameters further includes the steps of controlling the hybrid vehicle 1000 to enter a series mode when the wheel side required torque is greater than a second wheel side torque threshold value; determining the wheel side required power based on the wheel side required torque and the vehicle speed; driving the generator 30 to generate power based on a predetermined power when operating at the optimal eco point of the engine 10, and controlling the engine 10 to operate at the optimal eco point with a predetermined power so as to output power to the wheel side by the traction motor 20; charging the power battery 40 by the generator 30 using the excess power when the generated power of the generator 30 is greater than the wheel side required power; and controlling the engine 10 to increase the output power of the engine 10 and to operate at the eco line of the engine 10 in response to the wheel side required power when the generated power of the generator 30 is less than the wheel side required power.

[0134] In some embodiments of the present disclosure, the step of controlling the engine 10, the traction motor 20, and the generator 30 based on the driving parameters includes the steps of determining a third wheel-side torque threshold at which the hybrid vehicle 1000 enters the series mode based on the SOC of the power battery 40 and the vehicle speed when the vehicle speed of the hybrid vehicle 1000 is lower than a predetermined vehicle speed threshold, and controlling the hybrid vehicle 1000 to enter the series mode when the wheel-side required torque is equal to or greater than the third wheel-side torque threshold; determining a wheel-side required power based on the wheel-side required torque and the vehicle speed; and determining a power supply voltage when the engine 10 operates at an optimal eco point. The method further includes the steps of driving the generator 30 to generate electricity based on a certain electric power, and controlling the engine 10 to operate at an optimal eco point with the specified electric power so that the drive motor 20 outputs power to the wheel side, charging the power battery 40 with the generator 30 using the surplus electric power when the generated power of the generator 30 is greater than the power required by the wheel side, and controlling the engine 10 to increase the output power of the engine 10 and to operate at its eco line in response to the power required by the wheel side when the generated power of the generator 30 is less than the power required by the wheel side.

[0135] In some embodiments of the present disclosure, the step of controlling the engine 10, the traction motor 20, and the generator 30 based on the driving parameters further includes a step of checking whether the current SOC of the power battery 40 is smaller than a second predetermined value when the generated power of the generator 30 is smaller than the wheel side required power, and if so, controlling the output power of the engine 10 to respond to the wheel side required power, and controlling the output power of the engine 10 to continue to increase so as to charge the power battery 40 by the generator 30.

[0136] In some embodiments of the present disclosure, the step of controlling the engine 10, the traction motor 20 and the generator 30 based on the driving parameters further includes the steps of controlling the engine 10 to stop operation when the wheel-side torque requirement is less than a third wheel-side torque threshold, and controlling the power battery 40 to supply power to the traction motor 20 so that the power battery 40 responds to the wheel-side torque requirement.

[0137] In some embodiments of the present disclosure, when hybrid vehicle 1000 operates in series mode, if the SOC of power battery 40 is in a first predetermined interval, engine 10 is controlled to operate on a first eco line, and if the SOC of power battery 40 is in a second predetermined interval, engine 10 is controlled to operate on a second eco line, where the upper limit of the second predetermined interval is less than or equal to the lower limit of the first predetermined interval, and at the same rotation speed, the output torque of engine 10 operating on the second eco line is greater than or equal to the output torque of engine 10 operating on the first eco line.

[0138] In some embodiments of the present disclosure, when the hybrid vehicle 1000 operates in the parallel mode, if the SOC of the power battery 40 is in a third predetermined interval, the engine 10 is controlled to operate on the third ecoline, if the SOC of the power battery 40 is in a fourth predetermined interval, the engine 10 is controlled to operate on the fourth ecoline, if the SOC of the power battery 40 is in a fifth predetermined interval, the engine 10 is controlled to operate on the fifth ecoline, an upper limit of the fifth predetermined interval is equal to or lower than a lower limit of the fourth predetermined interval, and an upper limit of the fourth predetermined interval is equal to or lower than a lower limit of the third predetermined interval, the third ecoline is an optimal ecoline in the parallel mode, the fifth ecoline approximately coincides with an external characteristic line of the engine 10, and the fourth ecoline is between the fifth ecoline and the third ecoline.

[0139] In some embodiments of the present disclosure, when the hybrid vehicle 1000 operates in EV mode, if the SOC of the power battery 40 is less than a third predetermined value, the hybrid vehicle 1000 is controlled to operate in series mode or parallel mode based on the SOC of the power battery 40, the vehicle speed, and the wheel-side required torque, and the engine 10 is controlled to operate in the eco zone.

[0140] Note that, for an explanation of the control method for the hybrid vehicle 1000 in this disclosure, the explanation of the hybrid system 100 in this disclosure can be referred to, and therefore the explanation will be omitted here.

[0141] In the control method for the hybrid vehicle 1000 according to the embodiment of the present disclosure, the driving parameters of the hybrid vehicle 1000 are acquired, the engine 10, the drive motor 20, and the generator 30 are controlled based on the driving parameters, and charging and discharging control is performed on the power battery 40, so that the engine 10 operates in an eco-zone, and the equivalent fuel efficiency of the hybrid vehicle 1000 in the series mode, parallel mode, and EV mode is compared, and the operating mode with the lowest equivalent fuel efficiency is selected as the current operating mode of the hybrid vehicle 1000, so that the hybrid vehicle 1000 operates in the operating mode with the lowest equivalent fuel efficiency based on the driving parameters, and energy consumption is low, thereby effectively improving the economy of the hybrid vehicle 1000 and meeting the user's expectations for use.

[0142] In some embodiments, a computer-readable storage medium is further provided that stores a control program for the hybrid vehicle 1000 that, when executed by the processor 2200, implements the control method for the hybrid vehicle 1000 described above.

[0143] The computer-readable storage medium according to the embodiment of the present disclosure uses the above-mentioned control method for the hybrid vehicle 1000 to operate in an operating mode with the lowest equivalent fuel efficiency based on the driving parameters, and consumes less energy, thereby effectively improving the economic efficiency of the hybrid vehicle 1000 and meeting the user's usage expectations.

[0144] FIG. 13 is a schematic configuration diagram of a vehicle control unit 2000 according to one embodiment of the present disclosure. As shown in FIG. 13, the vehicle control unit 2000 includes a memory 2100, a processor 2200, and a control program for the hybrid vehicle 1000 that is stored in the memory 2100 and executable by the processor 2200. When the processor 2200 executes the control program for the hybrid vehicle 1000, the above-mentioned control method for the hybrid vehicle 1000 is realized.

[0145] The vehicle control unit 2000 according to the embodiment of the present disclosure uses the above-mentioned control method for the hybrid vehicle 1000 to operate the hybrid vehicle 1000 in an operating mode with the lowest equivalent fuel efficiency based on the driving parameters, and consumes less energy, thereby effectively improving the economic efficiency of the hybrid vehicle 1000 and meeting the user's expectations for use.

[0146] It should be noted that the logic or steps shown in the flowcharts or otherwise described herein, or the logic and steps, may be considered, for example, as an ordered list of executable instructions for implementing logical functions, and may be tangibly embodied in any computer-readable medium for use by or in conjunction with an instruction execution system, device, or appliance (e.g., a computer-based system, a system including processor 2200, or other system capable of reading instructions from and executing instructions from an instruction execution system, device, or appliance). As used herein, a "computer-readable medium" may be any device that can store, store, communicate, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or appliance. More specific examples (non-exhaustive list) of computer readable media include an electrical connection having one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory 2100 (RAM), a read only memory 2100 (ROM), an erasable programmable read only memory 2100 (EPROM or flash memory 2100), a fiber optic device, and a portable read only memory 2100 (CDROM). The computer readable medium may also be a paper or other suitable medium on which the program can be printed, for example by optically scanning the paper or other medium and then editing, interpreting, or otherwise processing in a suitable manner as required, to obtain the program electronically and subsequently store it in the computer memory 2100.

[0147] It should be understood that each part of the present disclosure can be realized by hardware, software, firmware, or a combination thereof. In the above embodiment, a plurality of steps or methods may be realized by software or firmware stored in the memory 2100 and executed by an appropriate instruction execution system. For example, when realized by hardware, as in the other embodiments, it can be realized by any one or combination of known techniques in the art, such as a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combination logic gate circuit, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0148] In the description of this specification, a description that refers to the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, exemplary expressions of the above terms are not necessarily limited to the same embodiment or example. In addition, the specific features, structures, materials, or characteristics described can be appropriately combined in any one or more embodiments or examples.

[0149] Additionally, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or suggest relative importance or quantity of the technical features depicted. Thus, a feature qualified with "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of this disclosure, "plurality" means at least two, e.g., two, three, etc., unless otherwise clearly and specifically limited.

[0150] In the present disclosure, unless otherwise specified and limited, the terms "attached", "coupled", "connected", "fixed", etc. should be understood in a broad sense, and unless otherwise specified, may be, for example, a fixed connection, a detachable connection, or an integral connection, may be a mechanical connection, an electrical connection, a direct connection, an indirect connection via an intermediate medium, or a relationship of internal communication between two elements or an interaction between two elements. A person skilled in the art can understand the specific meaning of the above terms in the present disclosure based on the specific situation.

[0151] Although the embodiments of the present disclosure have been shown and described above, the above embodiments are illustrative and should not be understood as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present disclosure. [Explanation of symbols]

[0152] 1000 Hybrid Cars 100 Hybrid System 10 Engine 20 Drive motor 30 Generator 40 Power battery 50 Controller 60 Dual Electrical Control Module 61 First inverter 62 Second inverter 63 DC / DC 70 Gearbox 80 Final reduction gear C1 Clutch 2000 Vehicle Control Unit 2100 Memory 2200 Processor

Claims

1. A control method for a hybrid vehicle including an engine that selectively outputs power to wheels, a drive motor that outputs power to the wheels, a generator connected to the engine and driven by the engine to generate power, and a power battery that supplies power to the drive motor, is charged based on an AC current output from the generator or the drive motor, and has a capacity equal to or greater than a first predetermined capacity, comprising: acquiring driving parameters of a hybrid vehicle; A step of controlling the engine, the drive motor, and the generator based on the traveling parameters and controlling charging and discharging of the power battery, thereby operating the engine in an eco zone; selecting an operation mode with the lowest equivalent fuel consumption as a current operation mode of the hybrid vehicle by comparing the equivalent fuel consumption of the hybrid vehicle in a series mode, a parallel mode, and an EV mode; and controlling the hybrid vehicle to operate in a series mode, a parallel mode, or an EV mode based on the driving parameters. The traveling parameters include at least one of a wheel side required torque, an SOC of the power battery, and a vehicle speed of the hybrid vehicle. A method for controlling a hybrid vehicle.

2. When the engine is operated in an EcoZone: if the SOC of the power battery is equal to or greater than a first predetermined value, the engine is controlled to operate at an optimum eco line, or if the SOC of the power battery is smaller than a first predetermined value and the output power of the engine is equal to or greater than a wheel side required power, the engine is controlled to operate at an optimum eco line; 2. The method of claim 1, wherein the magnitude of said first predetermined value is inversely correlated with the magnitude of said first predetermined capacity.

3. 3. The control method for a hybrid vehicle according to claim 1, wherein when the hybrid vehicle is in a series mode, the engine charges the power battery by the generator, and when the hybrid vehicle is in a parallel mode, the engine charges the power battery by the traction motor.

4. The step of controlling the engine, the traction motor, and the generator based on the driving parameters when the hybrid vehicle is in a parallel mode includes: determining the wheel side required torque; when the wheel-side required torque is smaller than an output torque of the engine when operating on an eco line, controlling the engine to operate on an eco line in response to the wheel-side required torque, and controlling the engine to drive the traction motor to generate electricity and to charge the power battery using excess energy output from the engine by the traction motor; 4. The control method for a hybrid vehicle according to claim 1, further comprising the steps of: when the wheel-side required torque is greater than an output torque of the engine when operating on an Ecoline, controlling the engine to operate on an Ecoline, and controlling the power battery to supply power to the drive motor so that both the power battery and the engine respond to the wheel-side required torque.

5. When the hybrid vehicle is in a series mode, the step of controlling the engine, the traction motor, and the generator based on the driving parameters includes: determining a wheel-side required power based on the wheel-side required torque and the vehicle speed; a step of controlling the engine to operate on an eco line by driving a generator to generate electricity based on an output torque of the engine when operating on an eco line and outputting power to the wheel side by a drive motor; When the generated power of the generator is greater than the wheel side required power, charging the power battery by the generator using the surplus power; and when the generated power of the generator is smaller than the wheel side required power, controlling the power battery to supply power to the drive motor so that both the engine and the power battery respond to the wheel side required power.

6. The step of controlling the engine, the drive motor, and the generator based on the traveling parameters includes: determining a first wheel-side torque threshold at which the hybrid vehicle enters a parallel mode and a second wheel-side torque threshold at which the hybrid vehicle exits a parallel mode based on an SOC of the power battery and the vehicle speed of the hybrid vehicle when the vehicle speed of the hybrid vehicle is equal to or greater than a predetermined vehicle speed threshold, and controlling the hybrid vehicle to enter the parallel mode when the wheel-side required torque is equal to or greater than the first wheel-side torque threshold and equal to or less than the second wheel-side torque threshold; if the wheel-side required torque is greater than an output torque of the engine when operating on an eco line, controlling the engine to operate on an eco line and controlling the power battery to supply power to the drive motor so that both the engine and the power battery respond to the wheel-side required torque; if the wheel-side required torque is smaller than an output torque of the engine when operating on an eco line, controlling the engine to operate on an eco line in response to the wheel-side required torque, and controlling the engine to drive the traction motor to generate electricity and to charge the power battery using excess energy output from the engine by the traction motor; and if the wheel-side required torque is equal to an output torque of the engine when operating on an eco line, controlling the engine to operate on an eco line so as to respond solely to the wheel-side required torque.

7. 7. The method for controlling a hybrid vehicle according to claim 6, wherein the magnitudes of the first wheel-side torque threshold and the second wheel-side torque threshold are positively correlated with the magnitude of an SOC of the power battery.

8. 7. The method of claim 6, wherein when the hybrid vehicle is operated in a parallel mode, the vehicle speed at which the engine is engaged in operation is inversely related to the magnitude of the power battery's SOC.

9. The step of controlling the engine, the drive motor, and the generator based on the traveling parameters includes:

7. The hybrid vehicle control method according to claim 6, further comprising the steps of: controlling the engine to stop operation when the wheel-side required torque is smaller than the first wheel-side torque threshold; and controlling the power battery to supply power to the drive motor so that the wheel-side required torque is responded to by the power battery.

10. The step of controlling the engine, the drive motor, and the generator based on the traveling parameters includes: controlling the hybrid vehicle to enter a series mode if the wheel side torque request is greater than the second wheel side torque threshold; determining a wheel-side required power based on the wheel-side required torque and the vehicle speed; A step of controlling the engine so as to operate at the optimum eco point with a predetermined electric power, by driving a generator to generate electric power based on a predetermined electric power when the engine operates at an optimum eco point, and by outputting power to the wheel side by a drive motor; When the generated power of the generator is greater than the wheel side required power, charging the power battery by the generator using the surplus power; 7. The control method for a hybrid vehicle according to claim 6, further comprising the steps of: when the generated power of the generator is smaller than the wheel side required power, controlling the engine to increase output power, and controlling the engine to operate on an engine eco line in response to the wheel side required power.

11. The step of controlling the engine, the drive motor, and the generator based on the traveling parameters includes: determining a third wheel-side torque threshold at which the hybrid vehicle enters a series mode based on an SOC of the power battery and the vehicle speed when the vehicle speed of the hybrid vehicle is lower than a predetermined vehicle speed threshold, and controlling the hybrid vehicle to enter the series mode when the wheel-side required torque is equal to or greater than the third wheel-side torque threshold; determining a wheel-side required power based on the wheel-side required torque and the vehicle speed; A step of controlling the engine so as to operate at the optimum eco point with a predetermined electric power, by driving a generator to generate electric power based on a predetermined electric power when the engine operates at an optimum eco point, and by outputting power to the wheel side by a drive motor; When the generated power of the generator is greater than the wheel side required power, charging the power battery by the generator using the surplus power; 7. The control method for a hybrid vehicle according to claim 6, further comprising the steps of: when the generated power of the generator is smaller than the wheel side required power, controlling the engine to increase output power, and controlling the engine to operate on an engine eco line in response to the wheel side required power.

12. The step of controlling the engine, the drive motor, and the generator based on the traveling parameters includes:

12. The control method for a hybrid vehicle according to claim 10 or 11, further comprising the steps of: when the generated power of the generator is smaller than the wheel side required power, checking whether the current SOC of the power battery is smaller than a second predetermined value; and if so, controlling the output power of the engine to respond to the wheel side required power, and controlling the output power of the engine to continue to increase so as to charge the power battery by the generator.

13. The step of controlling the engine, the drive motor, and the generator based on the traveling parameters includes:

12. The control method for a hybrid vehicle according to claim 11, further comprising the steps of: controlling the engine to stop operation when the wheel-side required torque is less than the third wheel-side torque threshold; and controlling the power battery to supply power to the drive motor so as to respond to the wheel-side required torque by the power battery.

14. 14. The method for controlling a hybrid vehicle according to claim 11 or 13, wherein the magnitude of the third wheel-side torque threshold is positively correlated with the magnitude of an SOC of the power battery.

15. When the hybrid vehicle is operated in series mode, If the SOC of the power battery is within a first predetermined range, the engine is controlled to operate on a first eco line; 4. The control method for a hybrid vehicle according to claim 1, wherein if an SOC of the power battery is in a second predetermined interval, the engine is controlled to operate on a second eco line, an upper limit of the second predetermined interval is equal to or lower than a lower limit of the first predetermined interval, the first eco line is an optimum eco line in a series mode, and an output torque of the engine operating on the second eco line is equal to or greater than an output torque of the engine operating on the first eco line at a same rotation speed.

16. When the hybrid vehicle is operated in a parallel mode, If the SOC of the power battery is within a third predetermined range, the engine is controlled to operate on a third eco line; If the SOC of the power battery is in a fourth predetermined section, the engine is controlled to operate on a fourth eco line; 4. The control method for a hybrid vehicle according to claim 1, wherein if the SOC of the power battery is in a fifth predetermined interval, the engine is controlled to operate on a fifth ecoline, an upper limit of the fifth predetermined interval is equal to or lower than a lower limit of the fourth predetermined interval, and an upper limit of the fourth predetermined interval is equal to or lower than a lower limit of the third predetermined interval, the third ecoline is an optimum ecoline in a parallel mode, the fifth ecoline approximately coincides with an external characteristic line of the engine, and the fourth ecoline is between the fifth ecoline and the third ecoline.

17. When the hybrid vehicle operates in an EV mode, 4. The hybrid vehicle control method according to claim 1, further comprising the steps of: if the SOC of the power battery is smaller than a third predetermined value, controlling the hybrid vehicle to operate in a series mode or a parallel mode based on the SOC of the power battery, the vehicle speed, and the wheel-side required torque, and controlling the engine to operate in an eco zone.

18. A computer-readable storage medium storing a hybrid vehicle control program that, when executed by a processor, realizes the hybrid vehicle control method according to any one of claims 1 to 17.

19. A vehicle control unit including a memory, a processor, and a hybrid vehicle control program stored in the memory and executable by the processor, the processor implementing the hybrid vehicle control method according to any one of claims 1 to 17 when it executes the hybrid vehicle control program.

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