Method of controlling a generator in a vehicle and vehicle

Abstract

The application discloses a control method of a generator in a vehicle and the vehicle. The method comprises the following steps: determining an actual torque of an engine in the vehicle; determining a power generation demand of the generator based on the actual torque and a permissible power generation torque of the generator, wherein the permissible power generation torque is determined based on a permissible power generation power of the generator; and controlling the generator to generate power based on the power generation demand. The application solves the technical problem of wheel end torque fluctuation or engine speed fluctuation.

Description

Technical Field

[0001] This invention relates to the field of vehicles, and more specifically, to a method for controlling a generator in a vehicle and a vehicle. Background Technology

[0002] In dual-motor hybrid systems, during coasting or braking recovery in series mode, the power demand of the drive motor wheel-end coasting or braking recovery and the generator power demand are coupled, affecting each other's power or torque capabilities.

[0003] Currently, the balance between the regenerative braking power of the drive motor wheel end and the generator power generation power is usually achieved by limiting the regenerative braking capacity of the drive motor and allocating the reserved capacity to the generator speed regulation. However, this method can only partially decouple the regenerative braking power of the drive motor wheel end and the generator power generation power, and still cannot balance the regenerative braking power of the drive motor wheel end and the generator power generation power, thus resulting in problems such as wheel end torque fluctuations or engine speed fluctuations.

[0004] There is currently no effective solution to the aforementioned problems of wheel-end torque fluctuations or engine speed fluctuations. Summary of the Invention

[0005] This invention provides a method for controlling a generator in a vehicle and a vehicle in general, to at least solve the technical problems of wheel-end torque fluctuation or engine speed fluctuation.

[0006] According to one aspect of the present invention, a method for controlling a generator in a vehicle is provided. The method may include: determining the actual torque of an engine in the vehicle; determining the generator's power demand based on the actual torque and the generator's allowable generating torque, wherein the allowable generating torque is determined based on the generator's allowable generating power; and controlling the generator to generate electricity based on the power demand.

[0007] Optionally, the generator's power demand is determined based on the actual torque and the generator's allowable generating torque, including: determining the speed ratio of the reducer between the generator and the motor in the vehicle, and determining the product of the actual torque and the speed ratio; and determining the power demand based on the product of the actual torque and the speed ratio and the allowable generating torque.

[0008] Optionally, the power generation demand is determined based on the product of the actual torque and the reducer ratio and the allowable generating torque, including: in response to the product of the actual torque and the reducer ratio being greater than the allowable generating torque, the power generation demand is determined as the product of the generator's minimum idle speed reserve power and the motor efficiency.

[0009] Optionally, the method further includes: in response to the product of the actual torque and the reducer ratio being greater than the allowable generator torque, determining the engine torque demand in the vehicle as a target value, the allowable generator power as the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor as the allowable motor recovery power, and the generator speed as the generator idle speed.

[0010] Optionally, the power generation demand is determined based on the product of the actual torque and the reducer ratio and the allowable power generation torque, including: in response to the product of the actual torque and the reducer ratio being less than or equal to the allowable power generation torque, the power generation demand is determined to be the power generation demand corresponding to the engine's idle speed, and is less than or equal to the maximum power generation demand corresponding to the idle speed.

[0011] Optionally, the method further includes: in response to the product of the actual torque and the reducer ratio being less than or equal to the allowable generator torque, determining that the torque demand of the engine in the vehicle is greater than the target value, the allowable generator power is the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor is the allowable regenerative power of the motor, and the generator speed is the generator idle speed.

[0012] Optionally, the method further includes: determining the quotient between the allowable charging power of the battery in the vehicle and the motor efficiency, and determining the difference between the quotient and the minimum idle speed reserve power of the generator; and determining the minimum value between the difference between the quotient and the minimum idle speed reserve power and the external characteristic power of the motor as the allowable regenerative power of the motor.

[0013] Optionally, the method further includes: determining the product between the actual power of the motor and the motor efficiency; determining the difference between the product of the actual power of the motor and the motor efficiency and the allowable charging power of the battery in the vehicle; and determining the allowable generating power of the generator by taking the minimum value between the difference and the external characteristic power of the generator.

[0014] Optionally, the method further includes: determining the product of the allowable power generation and the standard value; and determining the quotient between the product of the allowable power generation and the standard value and the generator speed as the allowable power generation torque.

[0015] According to another aspect of the present invention, a control device for a generator in a vehicle is also provided. The device may include: a first determining unit for determining the actual torque of the engine in the vehicle; a second determining unit for determining the generator's power demand based on the actual torque and the generator's allowable generating torque, wherein the allowable generating torque is determined based on the generator's allowable generating power; and a control unit for controlling the generator to generate power based on the power demand.

[0016] According to another aspect of the present invention, a vehicle is also provided. This vehicle is used to execute the control method for a generator in a vehicle according to the embodiments of the present invention.

[0017] According to another aspect of the present invention, a computer-readable storage medium is also provided. The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device where the computer-readable storage medium is located to perform the control method for a generator in a vehicle according to the embodiments of the present invention.

[0018] In this embodiment of the invention, the actual torque of the engine in the vehicle is determined; based on the actual torque and the allowable generating torque of the generator, the generator's power demand is determined, wherein the allowable generating torque is determined based on the generator's allowable generating power; and the generator is controlled to generate power based on the power demand. In other words, this embodiment of the invention determines the actual torque of the engine, determines the generator's power demand based on the actual torque and the generator's allowable generating torque, and further controls the generator's power generation based on the generator's power demand, thereby achieving the technical effect of avoiding wheel-end torque fluctuations or engine speed fluctuations, and solving the technical problem of wheel-end torque fluctuations or engine speed fluctuations. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0020] Figure 1 This is a flowchart of a control method for a generator in a vehicle according to an embodiment of the present invention;

[0021] Figure 2 This is a flowchart illustrating the calculation of allowable reclaimed power of a motor and allowable generated power of a generator according to an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of a dual-motor hybrid configuration according to an embodiment of the present invention;

[0023] Figure 4 This is a flowchart of another method for controlling a generator in a vehicle according to an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of a control device for a generator in a vehicle according to an embodiment of the present invention. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first," "second," etc., in the specification and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0027] Example 1

[0028] According to an embodiment of the present invention, an embodiment of a method for controlling a generator in a vehicle is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0029] Figure 1 This is a flowchart of a control method for a generator in a vehicle according to an embodiment of the present invention, such as... Figure 1 As shown, the method may include the following steps:

[0030] Step S102: Determine the actual torque of the engine in the vehicle.

[0031] In the technical solution provided by step S102 of the present invention, the actual torque of the engine in the vehicle can be determined. The engine torque can be the rotational torque generated when the engine is driven by input power. The actual torque of the engine can be the real torque generated by the engine during operation, which can be represented by T. 发动机实际 express.

[0032] Step S104: Based on the actual torque and the generator's allowable generating torque, determine the generator's power demand, wherein the allowable generating torque is determined based on the generator's allowable generating power.

[0033] In the technical solution provided in step S104 of the present invention, the allowable generating torque of the generator can be determined based on the allowable generating power of the generator. Based on the determined actual torque of the engine and the allowable generating torque of the generator, the generator's power demand can be determined. The allowable generating torque of the generator can be the maximum torque that the generator can withstand under normal operating conditions, and can be expressed in T. 发电机许用发电 The generator's power demand can be expressed as the power required by the generator during operation, and can be represented by P. 发电机发电需求 The allowable generating power of a generator can be expressed as the maximum power that the generator can continuously output during long-term operation, which can be represented by P. 发电机许用发电 express.

[0034] Optionally, the allowable generating power P of the generator 发电机许用发电 The allowable generating power P of the motor varies with the actual regenerative power recovered by the generator. When the generator and engine begin coasting or regenerative braking, the allowable generating power P of the motor varies. 发电机许用发电 The allowable generating torque T of the generator is getting smaller and smaller. 发电机许用发电 It is also getting smaller and smaller. Based on the allowable generating power P of the generator 发电机许用发电 The allowable generating torque T of the generator can be determined using the following formula. 发电机许用发电 :

[0035] T 发电机许用发电 =P 发电机许用发电 *9550 / n 发电机

[0036] Where, n 发电机 This can be used to represent the rotational speed of a generator, typically expressed as revolutions per minute or rotational speed. It should be noted that the number 9550 in the formula can be changed according to the actual situation.

[0037] Step S106: Control the generator to generate electricity based on the power demand.

[0038] In the technical solution provided by step S106 of the present invention, the generator power generation can be controlled based on the generator power generation demand.

[0039] In steps S102 to S106 of the present invention, the actual torque of the engine in the vehicle is determined; based on the actual torque and the allowable generating torque of the generator, the generator's power demand is determined, wherein the allowable generating torque is determined based on the generator's allowable generating power; and the generator is controlled to generate power based on the power demand. In other words, the embodiments of the present invention determine the actual torque of the engine, determine the generator's power demand based on the actual torque of the engine and the allowable generating torque of the generator, and further control the generator's power generation based on the generator's power demand, thereby achieving the technical effect of avoiding wheel-end torque fluctuations or engine speed fluctuations, and solving the technical problem of wheel-end torque fluctuations or engine speed fluctuations.

[0040] The method described in this embodiment will be further described below.

[0041] As an optional embodiment, step S104, determining the generator's power demand based on the actual torque and the generator's allowable generating torque, includes: determining the speed ratio of the reducer between the generator and the motor in the vehicle, and determining the product of the actual torque and the speed ratio; and determining the power demand based on the product of the actual torque and the speed ratio and the allowable generating torque.

[0042] In this embodiment, the speed ratio of the reducer between the generator and the motor in the vehicle can be determined, and the product of the actual engine torque and the speed ratio of the reducer can be determined. Based on the determined product of the actual engine torque and the speed ratio of the reducer, and the allowable generating torque of the generator, the generator's power demand can be determined. The motor in the vehicle can be a drive motor. The speed ratio of the reducer can be the ratio between the generator's rotational speed and the engine's rotational speed, and can be expressed as R. 发电机 / 发动机 express.

[0043] Optionally, based on a determined actual engine torque T 发动机实际 and reducer speed ratio R 发电机 / 发动机 The product of the engine's actual torque and the reducer's speed ratio can be determined as T. 发动机实际 *R 发电机 / 发动机 Based on the product T between the actual engine torque and the reducer ratio. 发动机实际 *R 发电机 / 发动机 This allows us to determine the relationship between the product of the engine's actual torque and the reducer's speed ratio, and the generator's allowable torque. Based on this relationship, the generator's power demand P can be determined. 发电机发电需求 .

[0044] For example, when the generator's allowable generating torque T 发电机许用发电Less than the product T between the engine's actual torque and the reducer's speed ratio. 发动机实际 *R 发电机 / 发动机 When, that is, when T 发电机许用发电 <T 发动机实际 *R 发电机 / 发动机 When necessary, a fuel cut-off command needs to be issued to the engine to prevent it from overspeeding due to insufficient generator power output. Furthermore, based on the relationship between the product of the engine's actual torque and the reducer's speed ratio, and the generator's allowable generating torque, the generator's power demand P can be determined. 发电机发电需求 .

[0045] As an optional implementation method, the power generation demand is determined based on the product of the actual torque and the reducer ratio and the allowable generating torque, including: in response to the product of the actual torque and the reducer ratio being greater than the allowable generating torque, determining the power generation demand as the product of the generator's minimum idle speed reserve power and the motor efficiency.

[0046] In this embodiment, the relationship between the product of the engine's actual torque and the reducer ratio, and the generator's allowable generating torque can be determined. When the product of the engine's actual torque and the reducer ratio is greater than the generator's allowable generating torque, in response to this, the generator's power demand can be determined as the product of the generator's minimum idle speed reserve power and the generator efficiency. The generator's minimum idle speed reserve power can be the minimum power that the generator needs to reserve to meet its own operating requirements during idle operation, which can be represented by P. 最小怠速预留 For example, it could be 2 kilowatts (kW). This is just an example and does not impose specific limitations on the minimum idle speed reserve power of the generator. Motor efficiency can be the efficiency of the drive motor, specifically the energy conversion efficiency of the drive motor when converting electrical energy into mechanical energy, and can be expressed in μ. 驱动电机 express.

[0047] Optionally, when T 发电机许用发电 <T 发动机实际 *R 发电机 / 发动机 When the generator prioritizes regeneration via the wheel-end drive motor, it can still maintain a stable idle speed. At this time, the generator's power demand is the product of the generator's minimum idle reserve power and the motor efficiency, i.e., P. 发电机发电需求 =P 最小怠速预留 *μ 驱动电机 P 最小怠速预留 This takes into account the minimum stable power when the generator speed drops to the idle speed.

[0048] As an optional embodiment, the method further includes: in response to the product of the actual torque and the reducer ratio being greater than the allowable generator torque, determining the engine torque demand in the vehicle as a target value, the allowable generator power as the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor as the allowable motor recovery power, and the generator speed as the generator idle speed.

[0049] In this embodiment, the relationship between the product of the engine's actual torque and the reducer ratio, and the allowable generating torque of the generator can be determined. When the product of the engine's actual torque and the reducer ratio is greater than the allowable generating torque of the generator, in response to this, the torque requirement of the engine in the vehicle can be determined as the target value, the allowable generating power of the generator as the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor as the allowable regenerative braking power, and the generator speed as the generator idle speed. The engine's torque requirement can be the magnitude of the torque required by the engine during operation, which can be represented by T. 发动机扭矩需求 The target value can be the difference between the actual output torque and the theoretical output torque of the engine when the speed is too high or too low, due to mechanical and transmission losses. It can be represented by TrqLoss. For example, the target value can be -30 N·m. This is just an example and does not impose any specific restrictions on the target value. The actual power of the motor can be the actual output power of the drive motor under actual working conditions, which can be represented by P. 驱动电机实际 The allowable regenerative braking power of a motor is the maximum power that the drive motor can convert from mechanical energy into electrical energy and return to the power source during braking. It can be represented by P. 驱动电机许用回收 The generator idle speed can be expressed as the generator's rotational speed under no-load conditions, and can be represented by n. 发电机怠速 express.

[0050] Optionally, when the generator and engine begin coasting or regenerative braking, the actual power P of the drive motor is... 驱动电机实际 As it gets larger, the allowable generating power P of the generator increases. 发电机许用发电 The allowable generating torque T of the generator is getting smaller and smaller. 发电机许用发电 And it's getting smaller and smaller. When T 发电机许用发电 <T 发动机实际 *R 发电机 / 发动机 At this time, a fuel cut-off command needs to be issued to the engine, meaning that the engine's torque demand in the vehicle can be determined as the target value, i.e., T. 发动机扭矩需求 =TrqLoss, to prevent engine overspeed due to insufficient generator power output. In this case, the actual power of the drive motor is the allowable regenerative braking power of the drive motor, i.e., P.驱动电机实际 =P 驱动电机许用回收 The allowable generating power of a generator is the product of the generator's minimum idle speed reserve power and the generator efficiency, i.e., P. 发电机许用发电 =P 最小怠速预留 *μ 驱动电机 At the same time, by looking up the table, we can obtain the generator's speed as its idle speed, i.e., n. 发电机 =n 发电机怠速 .

[0051] As an optional embodiment, the power generation demand is determined based on the product of the actual torque and the reducer ratio and the allowable power generation torque, including: in response to the product of the actual torque and the reducer ratio being less than or equal to the allowable power generation torque, the power generation demand is determined to be the power generation demand corresponding to the engine's idle speed, and is less than or equal to the maximum power generation demand corresponding to the idle speed.

[0052] In this embodiment, the relationship between the product of the engine's actual torque and the reducer ratio, and the generator's allowable generating torque can be determined. When the determined product of the engine's actual torque and the reducer ratio is less than or equal to the generator's allowable generating torque, the generator power demand can be determined as the generator power demand corresponding to the engine's idle speed, and this generator power demand is less than or equal to the maximum generator power demand corresponding to the idle speed. The maximum generator power demand can be based on the idle speed n. 发电机怠速 The maximum power demand of the generator can be derived by looking up the table. For example, it can be 15kW. This is just an example and no specific limit is made on the maximum power demand.

[0053] Optionally, the generator can maintain a minimum stable idle speed throughout the recovery process. However, when the actual recovered power of the drive motor begins to decrease, assuming the final generator power demand can be represented by P... 发电机发电需求1 This indicates that the final n 发电机 n can be used 发电机1 This indicates that the initial n 发电机 n can be used 发电机0 It means that P 发电机许用发电 and T 发电机许用发电 It will get bigger and bigger, then P 发电机发电需求1 =min[P 发电机发电需求 P 发电机许用发电 ],P 发电机发电需求1 It will also follow P 发电机许用发电 It increases with the increase of the generator's rotational speed n. 发电机 By P 发电机发电需求1 From the table, we can see that the generator's rotational speed n is... 发电机 It will also follow P 发电机发电需求1 It increases as n increases. 发电机Increase to n 发电机1 When this happens, it will cause the actual generator speed n 发电机 During recovery operation, the initial rotational speed n may decrease. 发电机0 Decrease to n 发电机怠速 Then rise to n 发电机1 , where n 发电机0 and n 发电机1 All are greater than or equal to n 发电机怠速 That is, the generator speed does not decrease linearly and then remain constant after pedal operation, but fluctuates.

[0054] For example, to avoid the aforementioned generator speed fluctuations, the P value in the recovery operating condition... 发电机发电需求 The idle speed n must be less than or equal to the idle speed. 发电机怠速 The maximum power generation demand calculated from the table is 15kW. In other words, the power generation demand of generators with a maximum power generation demand below 15kW is calculated by looking up the generator speed n from the table. 发电机 This is equal to the idle speed of 1300 revolutions per minute (rpm).

[0055] As an optional embodiment, the method further includes: in response to the product of the actual torque and the reducer ratio being less than or equal to the allowable generator torque, determining that the torque demand of the engine in the vehicle is greater than a target value, the allowable generator power is the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor is the allowable regenerative power of the motor, and the generator speed is the generator idle speed.

[0056] In this embodiment, when the product of the engine's actual torque and the reducer's speed ratio is less than or equal to the generator's allowable generating torque, in response to the product of the engine's actual torque and the reducer's speed ratio being less than or equal to the generator's allowable generating torque, it can be determined that the engine's torque demand in the vehicle is greater than the target value, the generator's allowable generating power is the product of the generator's minimum idle speed reserve power and the motor efficiency, the drive motor's actual power is the drive motor's allowable regenerative power, and the generator's speed is the generator's idle speed.

[0057] Optionally, when T 发电机许用发电 ≥T 发动机实际 *R 发电机 / 发动机 At that time, T can be determined 发动机扭矩需求 >TrqLoss、P 发电机许用发电 =P 最小怠速预留 *μ 驱动电机 P 驱动电机实际 =P 驱动电机许用回收 , and n 发电机 =n 发电机怠速 .

[0058] As an optional embodiment, the method further includes: determining the quotient between the allowable charging power of the battery in the vehicle and the motor efficiency, and determining the difference between the quotient and the minimum idle speed reserve power of the generator; and determining the minimum value between the difference between the quotient and the minimum idle speed reserve power and the external characteristic power of the motor as the allowable regenerative power of the motor.

[0059] In this embodiment, the quotient between the allowable charging power of the battery and the motor efficiency can be determined, and the difference between the quotient and the minimum idle speed reserve power of the generator can be determined. Furthermore, the minimum value between the difference between the quotient and the minimum idle speed reserve power and the external characteristic power of the motor is determined as the allowable regenerative braking power of the motor. The allowable charging power of the battery can be the maximum power that the battery can withstand during charging, which can be represented by P. 电池许用充电 The external characteristic power of a motor can be expressed as the maximum power that the drive motor can output under specific operating conditions, and can be represented by P. 驱动电机外特性 The allowable regenerative power of a motor is the maximum power that the drive motor can recover and utilize during braking, expressed as P. 驱动电机许用回收 express.

[0060] Optionally, this embodiment first determines the allowable charging power P of the battery in the vehicle. 电池许用充电 and motor efficiency μ 驱动电机 The quotient between the two is P 电池许用充电 / μ 驱动电机 And it is possible to determine the quotient P 电池许用充电 / μ 驱动电机 and the minimum idle speed reserve power P of the generator 最小怠速预留 The difference between the two is P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 Furthermore, the difference P can be determined. 电池许用充电 / μ 驱动电机 -P 最小怠速预留 and the external characteristic power P of the drive motor 驱动电机外特性 The minimum value between them is min[(P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 ), P 驱动电机外特性 Finally, the minimum value was determined as the allowable regenerative power P of the drive motor. 驱动电机许用回收 That is, P 驱动电机许用回收 =min[(P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 ), P 驱动电机外特性 ].

[0061] As an optional embodiment, the method further includes: determining the product between the actual power of the motor and the motor efficiency; determining the difference between the product of the actual power of the motor and the motor efficiency and the allowable charging power of the battery in the vehicle; and determining the allowable generating power of the generator by taking the minimum value between the difference and the external characteristic power of the generator.

[0062] In this embodiment, the product of the motor's actual power and motor efficiency can be determined. Further, the difference between the product of the motor's actual power and motor efficiency and the allowable charging power of the vehicle's battery can be determined. Finally, the minimum value between this difference and the generator's external characteristic power can be used to determine the generator's allowable generating power. Here, the actual power of the drive motor can be the power consumed by the drive motor during actual operation, which can be represented by P. 驱动电机实际 The external characteristic power of a generator can be expressed as the power that the generator can output under load conditions, and can be represented by P. 发电机外特性 express.

[0063] Optionally, this embodiment first determines the actual power P of the drive motor. 驱动电机实际 and motor efficiency μ 驱动电机 The product of the two is P 驱动电机实际 *μ 驱动电机 Furthermore, it is possible to determine the product P between the actual power of the drive motor and the motor efficiency. 驱动电机实际 *μ 驱动电机 And the permissible charging power P of the battery in the vehicle 电池许用充电 The difference between the two is P 电池许用充电 -P 驱动电机实际 *μ 驱动电机 Furthermore, the difference P can be determined. 电池许用充电 -P 驱动电机实际 *μ 驱动电机 and the external characteristic power P of the generator 发电机外特性 The minimum value between the two is min[(P 电池许用充电 -P 驱动电机实际 *μ 驱动电机 ), P 发电机外特性 Finally, the minimum value was determined as the allowable generating power P of the generator. 发电机许用发电 That is, P 发电机许用发电 =min[(P 电池许用充电 -P 驱动电机实际 *μ 驱动电机 ), P 发电机外特性 ].

[0064] Optionally, the above calculation method for the allowable regenerative power of the drive motor and the allowable generating power of the generator can prioritize the regenerative power capability of the drive motor over the generating power capability of the generator, so as to prioritize ensuring the maximum regenerative energy at the wheel end and the drivability of the wheel end torque. At the same time, it is also to decouple the allowable regenerative power of the drive motor and the allowable generating power capability of the generator, so that the regenerative torque of the drive motor will not fluctuate due to fluctuations in generator power or torque.

[0065] Optionally, when the product P between the actual power of the drive motor and the motor efficiency... 驱动电机实际 *μ 驱动电机 The allowable charging power P of the battery in the vehicle 电池许用充电 The difference P between the two 电池许用充电 -P 驱动电机实际 *μ 驱动电机 The power is less than the generator's external characteristic power P. 发电机外特性 When the generator's allowable generating power is P, then the generator's allowable generating power is P. 发电机许用发电 =P 电池许用充电 -P 驱动电机实际 *μ 驱动电机 Due to the determined allowable regenerative braking power P of the drive motor 驱动电机许用回收 =min[(P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 ), P 驱动电机外特性 ], when P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 Less than P 驱动电机外特性 When this happens, the allowable regenerative braking power P of the drive motor is... 驱动电机许用回收 =P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 Therefore, the allowable generating power P of the generator... 发电机许用发电 =P 电池许用充电 -P 驱动电机实际 *μ 驱动电机 =P 电池许用充电 -(P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 )*μ 驱动电机 =P 最小怠速预留 *μ 驱动电机 .

[0066] As an optional embodiment, the method further includes: determining the product of the allowable power generation and a standard value; and determining the quotient between the product of the allowable power generation and the standard value and the generator speed as the allowable power generation torque.

[0067] In this embodiment, the product of the generator's allowable generating power and a standard value can be determined. Furthermore, the quotient between the product and the generator's rotational speed can be determined as the generator's allowable generating torque. The standard value can be a conversion factor for converting rotational speed per minute to rotational speed per hour, for example, 9550. This is merely an example and does not impose specific limitations on the content of the standard value.

[0068] Optionally, this embodiment determines the allowable generating power P of the generator. 发电机许用发电 The product of P and the standard value of 9550 is P. 发电机许用发电 *9550, and the product P can be determined. 发电机许用发电 *9550 and generator speed n 发电机 The quotient between the two is P 发电机许用发电 *9550 / n 发电机 Finally, the business P 发电机许用发电 *9550 / n 发电机 The allowable generating torque T of the generator is determined. 发电机许用发电 .

[0069] This embodiment determines the actual torque of the engine in the vehicle; based on the actual torque and the allowable generating torque of the generator, it determines the generator's power demand, wherein the allowable generating torque is determined based on the generator's allowable generating power; and it controls the generator's power generation based on the power demand. In other words, this embodiment determines the engine's actual torque, determines the generator's power demand based on the engine's actual torque and the generator's allowable generating torque, and further controls the generator's power generation based on the generator's power demand, thereby achieving the technical effect of avoiding wheel-end torque fluctuations or engine speed fluctuations, and solving the technical problem of wheel-end torque fluctuations or engine speed fluctuations.

[0070] Example 2

[0071] The technical solutions of the embodiments of the present invention will be illustrated below with reference to preferred embodiments.

[0072] Currently, in dual-motor hybrid systems, during regenerative braking or coasting in series mode, the regenerative braking power and the generator's power requirements are coupled, affecting each other's power or torque capabilities. This results in fluctuations in wheel-end torque or engine speed, which is more pronounced when battery charging capacity is low. To balance the regenerative braking power of the drive motor at the wheels and the generator's power output, ensuring both drivability at the regenerated wheels and a linear decrease in generator speed or torque with pedal input, a common approach is to limit the drive motor's regenerative braking capacity, allocating the reserved capacity to the generator for speed regulation. However, this method only partially decouples the power capabilities of the two systems and still cannot fully balance the regenerative braking power of the drive motor at the wheels and the generator's power output, thus resulting in fluctuations in wheel-end torque or engine speed.

[0073] As an alternative example, a control method, control system, and vehicle for improving energy recovery in hybrid electric vehicles are proposed. When the vehicle enters energy recovery mode, this method obtains the time interval between the current energy recovery and the previous one, the battery charging time under the current energy recovery mode, the battery temperature, and the battery state of charge (SOC). Based on the latter three, a target time interval is obtained. The total battery charging time is obtained by comparing the current energy recovery time interval with the target time interval. Furthermore, the maximum allowable charging power of the battery is obtained. Based on the current vehicle speed, brake pedal opening, and energy recovery intensity level, a second recovery power is obtained. The external characteristic power of the drive motor is also obtained. The minimum of the three powers is used as the actual recovery power of the drive motor. This method comprehensively considers the influence of battery charge, battery temperature, and battery charging time on the maximum allowable charging power of the battery, thereby improving the maximum energy recovery capability of the entire vehicle. However, this method does not address the problem of wheel torque fluctuations or engine speed fluctuations when the dual-motor hybrid system operates in series mode coasting or braking recovery conditions with low battery charging capability. This is because the coasting or braking recovery power and generator power are coupled, leading to fluctuations in wheel torque or engine speed.

[0074] As another alternative example, a method for controlling the braking torque of a hybrid vehicle and a hybrid vehicle are also proposed. This method calculates the maximum allowable power of motor energy recovery for the vehicle at present, sets the target acceleration based on the current brake pedal opening, and if the target acceleration is less than zero, it determines whether the maximum allowable power of motor energy recovery can make the vehicle's acceleration reach the target acceleration. If so, the motor braking is maintained until the vehicle's acceleration reaches the target acceleration; if not, the motor braking and engine auxiliary braking are controlled to brake together. This method realizes automatic control of motor braking or motor braking and engine auxiliary braking together according to actual operating conditions, effectively improving the safety of vehicle braking under slope conditions, and at a lower cost. However, this method does not address the problem of wheel-end torque fluctuations or engine speed fluctuations when the dual-motor hybrid vehicle is in series mode coasting or regenerative braking conditions with low battery charging capacity.

[0075] As another alternative example, an energy recovery method for hybrid vehicles is proposed. In this method, when the hybrid vehicle is driving in pure electric mode, it determines whether the driver has applied the brakes if the driver has not pressed the accelerator. If the driver has not applied the brakes, the motor speed is monitored. The motor speed is pre-divided into different stages from low to high, and a different motor braking torque is set for each stage. The motor braking torque is determined based on the real-time motor speed to recover the motor's braking energy. This method can control the motor with different braking torques in segments according to the motor speed, ensuring that the braking torque does not change abruptly when the hybrid vehicle recovers energy through motor braking, and ensuring a smooth transition. This ensures the smoothness of the hybrid vehicle and improves the driver's experience. However, this method does not address the problem of wheel-end torque fluctuations or engine speed fluctuations when the dual-motor hybrid vehicle is in series mode coasting or braking recovery conditions with low battery charging capacity.

[0076] To address the aforementioned issues, this embodiment proposes a control method for a generator in a vehicle. This method primarily addresses the problem of wheel-end torque fluctuations or engine speed fluctuations caused by the coupling between the recuperation power and generator power during coasting or regenerative braking in a dual-motor hybrid system when the battery charging capacity is low and the system is in series mode. This method ensures both wheel-end drivability during energy recovery and linear decrease in generator speed or torque with pedal movement, thereby achieving the technical effect of avoiding wheel-end torque fluctuations or engine speed fluctuations and solving the technical problems of wheel-end torque fluctuations or engine speed fluctuations.

[0077] Figure 2 This is a flowchart illustrating the calculation of allowable reclaimed power of a motor and allowable generated power of a generator according to an embodiment of the present invention, such as... Figure 2 As shown, the process for calculating the allowable reclaimed power of the motor and the allowable generated power of the generator may include the following steps:

[0078] Step S202: Establish the decoupling principle.

[0079] In step S202 above, a decoupling principle is established, prioritizing the maximum recoverable energy at the wheel end and the drivability of the wheel end torque. That is, the power recovery capability of the drive motor has a higher priority than the power generation capability of the generator.

[0080] Step S204: Calculate the allowable regenerative power of the motor.

[0081] In step S204 above, the allowable charging power P of the battery in the vehicle is first determined. 电池许用充电 and motor efficiency μ 驱动电机 The quotient between the two is P 电池许用充电 / μ 驱动电机And it is possible to determine the quotient P 电池许用充电 / μ 驱动电机 and the minimum idle speed reserve power P of the generator 最小怠速预留 The difference between the two is P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 Furthermore, the difference P can be determined. 电池许用充电 / μ 驱动电机 -P 最小怠速预留 and the external characteristic power P of the drive motor 驱动电机外特性 The minimum value between them is min[(P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 ), P 驱动电机外特性 Finally, the minimum value was determined as the allowable regenerative power P of the drive motor. 驱动电机许用回收 That is, P 驱动电机许用回收 =min[(P 电池许用充电 / μ 驱动电机 -P 最小怠速预留 ), P 驱动电机外特性 ].

[0082] Step S206: Calculate the allowable generating power of the generator.

[0083] In step S206 above, the actual power P of the drive motor is first determined. 驱动电机实际 and motor efficiency μ 驱动电机 The product of the two is P 驱动电机实际 *μ 驱动电机 Furthermore, it is possible to determine the product P between the actual power of the drive motor and the motor efficiency. 驱动电机实际 *μ 驱动电机 And the permissible charging power P of the battery in the vehicle 电池许用充电 The difference between the two is P 电池许用充电 -P 驱动电机实际 *μ 驱动电机 Furthermore, the difference P can be determined. 电池许用充电 -P 驱动电机实际 *μ 驱动电机 and the external characteristic power P of the generator 发电机外特性 The minimum value between the two is min[(P 电池许用充电 -P 驱动电机实际 *μ 驱动电机 ), P 发电机外特性 Finally, the minimum value was determined as the allowable generating power P of the generator. 发电机许用发电 That is, P 发电机许用发电 =min[(P 电池许用充电 -P 驱动电机实际 *μ 驱动电机 ), P 发电机外特性 ].

[0084] Figure 3This is a schematic diagram of a dual-motor hybrid configuration according to an embodiment of the present invention, as shown below. Figure 3 As shown, this dual-motor hybrid configuration may include a clutch 301, an engine 302, a generator 303, a power battery 304, a drive motor 305, and a coupler 306. The clutch allows for smooth engagement or temporary disengagement of the power from the engine 302 with the transmission, facilitating driver operations such as starting, stopping, and shifting gears. The engine 302 is connected to the generator 303, which is connected to the power battery 304. When the engine 302 is not running, the power battery 304 supplies power to the vehicle's electrical equipment. When the engine 302 is running, the generator 303 supplies power to the vehicle's electrical equipment and simultaneously charges the power battery 304, replenishing its energy. The power battery 304 is connected to the drive motor 305, which drives the movement of equipment in the vehicle and draws power from the power battery 304 via a high-voltage cable. Coupler 306 may include clutch 301, which can be used to connect the vehicle's power output to the engine 302, enabling the vehicle to start smoothly and reducing impact.

[0085] Figure 4 This is a flowchart of another method for controlling a generator in a vehicle according to an embodiment of the present invention, such as... Figure 4 As shown, the control method for the generator in this vehicle may include the following steps:

[0086] Step S402: Determine the allowable generating torque of the generator.

[0087] In step S402 above, the allowable generating power P of the generator is... 发电机许用发电 The actual regenerative power P of the drive motor varies with the actual regenerative braking power of the drive motor. When the generator and engine begin coasting or regenerative braking, the actual power P of the drive motor changes. 驱动电机实际 As it gets larger, the allowable generating power P of the generator increases. 发电机许用发电 The allowable generating torque T of the generator is getting smaller and smaller. 发电机许用发电 It is also getting smaller and smaller, based on the allowable generating power P of the generator. 发电机许用发电 The allowable generating torque T of the generator can be determined. 发电机许用发电 =P 发电机许用发电 *9550 / n 发电机 .

[0088] Step S404: Issue a fuel cut-off command to the engine.

[0089] In step S404 above, when T 发电机许用发电 <T 发动机实际 *R 发电机 / 发动机At this time, a fuel cut-off command needs to be issued to the engine, which means that the engine's torque demand in the vehicle is determined as the target value, i.e., T. 发动机扭矩需求 =TrqLoss, to prevent the engine speed from running out of control due to insufficient generator power output.

[0090] Step S406: Restore engine fuel supply.

[0091] In step S406 above, after the engine speed slowly decreases to idle speed and stabilizes, it is necessary to restore engine fuel supply and the generator performs idle power generation. At this time, the actual power of the drive motor is the allowable regenerative braking power of the drive motor, i.e., P. 驱动电机实际 =P 驱动电机许用回收 This means that the allowable generating power of the generator is the product of the generator's minimum idle speed reserve power and the motor efficiency, i.e., P. 发电机许用发电 =P 最小怠速预留 *μ 驱动电机 Meanwhile, by looking up the table, the generator's speed is found to be the generator's idle speed, i.e., n. 发电机 =n 发电机怠速 .

[0092] This embodiment determines the actual torque of the engine in the vehicle; based on the actual torque and the allowable generating torque of the generator, it determines the generator's power demand, wherein the allowable generating torque is determined based on the generator's allowable generating power; and it controls the generator's power generation based on the power demand. In other words, this embodiment determines the engine's actual torque, determines the generator's power demand based on the engine's actual torque and the generator's allowable generating torque, and further controls the generator's power generation based on the generator's power demand, thereby achieving the technical effect of avoiding wheel-end torque fluctuations or engine speed fluctuations, and solving the technical problem of wheel-end torque fluctuations or engine speed fluctuations.

[0093] Example 3

[0094] According to an embodiment of the present invention, a control device for a generator in a vehicle is also provided. It should be noted that this control device for a generator in a vehicle can be used to execute the control method for a generator in a vehicle described in Embodiment 1.

[0095] Figure 5 This is a schematic diagram of a control device for a generator in a vehicle according to an embodiment of the present invention, such as... Figure 5 As shown, the generator control device 500 in the vehicle may include: a first determining unit 502, a second determining unit 504, and a control unit 506.

[0096] The first determining unit 502 is used to determine the actual torque of the engine in the vehicle.

[0097] The second determining unit 504 is used to determine the generator's power demand based on the actual torque and the generator's allowable generating torque, wherein the allowable generating torque is determined based on the generator's allowable generating power.

[0098] Control unit 506 is used to control the generator to generate electricity based on the power demand.

[0099] Optionally, the second determining unit 504 includes: a first determining module, used to determine the speed ratio of the reducer between the generator and the motor in the vehicle, and to determine the product between the actual torque and the speed ratio; and a second determining module, used to determine the power demand for power generation based on the product of the actual torque and the speed ratio and the allowable power generation torque.

[0100] Optionally, the second determining module includes: a first determining submodule, used to determine the power generation demand as the product of the generator's minimum idle speed reserve power and the motor efficiency in response to the product of the actual torque and the reducer speed ratio being greater than the allowable generating torque.

[0101] Optionally, the device further includes: a third determining unit, configured to determine, in response to the product of the actual torque and the reducer ratio being greater than the allowable generator torque, the torque demand of the engine in the vehicle as a target value, the allowable generator power as the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor as the allowable regenerative power of the motor, and the speed of the generator as the generator idle speed.

[0102] Optionally, the second determining module includes: a second determining submodule, used to determine the power generation demand as the power generation demand corresponding to the engine's idle speed, and less than or equal to the maximum power generation demand corresponding to the idle speed, in response to the product between the actual torque and the reducer speed ratio being less than or equal to the allowable power generation torque.

[0103] Optionally, the device further includes: a fourth determining unit, configured to determine, in response to the product of the actual torque and the reducer ratio being less than or equal to the allowable generator torque, that the torque demand of the engine in the vehicle is greater than a target value, the allowable generator power is the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor is the allowable regenerative power of the motor, and the generator speed is the generator idle speed.

[0104] Optionally, the device further includes: a fifth determining unit, configured to determine the quotient between the allowable charging power of the battery in the vehicle and the motor efficiency, and to determine the difference between the quotient and the minimum idle speed reserve power of the generator; and a sixth determining unit, configured to determine the minimum value between the difference between the quotient and the minimum idle speed reserve power and the external characteristic power of the motor as the allowable regenerative power of the motor.

[0105] Optionally, the device further includes: a seventh determining unit for determining the product between the actual power of the motor and the motor efficiency; an eighth determining unit for determining the difference between the product of the actual power of the motor and the motor efficiency and the allowable charging power of the battery in the vehicle; and a ninth determining unit for determining the allowable generating power of the generator by taking the minimum value between the difference and the external characteristic power of the generator.

[0106] Optionally, the device further includes: a tenth determining unit for determining the product of the allowable power generation and the standard value; and an eleventh determining unit for determining the quotient between the product of the allowable power generation and the standard value and the speed of the generator as the allowable power generation torque.

[0107] In this embodiment of the invention, the first determining unit 502 determines the actual torque of the engine in the vehicle, and the second determining unit 504 determines the generator's power demand based on the actual torque and the generator's allowable generating torque, wherein the allowable generating torque is determined based on the generator's allowable generating power. The control unit 506 controls the generator to generate power based on the power demand. In other words, this embodiment of the invention, by determining the engine's actual torque, determining the generator's power demand based on the engine's actual torque and the generator's allowable generating torque, and further controlling the generator to generate power based on the generator's power demand, achieves the technical effect of avoiding wheel-end torque fluctuations or engine speed fluctuations, thus solving the technical problem of wheel-end torque fluctuations or engine speed fluctuations.

[0108] Example 4

[0109] According to an embodiment of the present invention, a vehicle is also provided for performing the control method of the generator in any of the vehicles in Embodiment 1.

[0110] Example 5

[0111] According to an embodiment of the present invention, a computer-readable storage medium is also provided, the storage medium including a stored program, wherein the program executes the control method of the generator in the vehicle in Embodiment 1.

[0112] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0113] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0114] In the several embodiments provided by this invention, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection can be through some interfaces; the indirect coupling or communication connection of units or modules can be electrical or other forms.

[0115] The units defined as separate components may or may not be physically separate. Similarly, the components displayed as units may or may not be physical units; they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0116] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0117] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0118] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for controlling a generator in a vehicle, characterized in that, include: Determine the actual torque of the engine in the vehicle; Determine the product of the motor's actual power and its efficiency; Determine the difference between the product of the actual power of the motor and the motor efficiency, and the allowable charging power of the battery in the vehicle; The minimum value between the difference and the external characteristic power of the generator is determined as the allowable generating power of the generator. Determine the speed ratio of the reducer between the generator and the motor in the vehicle, and determine the product between the actual torque and the speed ratio of the reducer; In response to the fact that the product of the actual torque and the speed ratio of the reducer is greater than the allowable generating torque of the generator, the generating power demand of the generator is determined to be the product of the minimum idle speed reserve power of the generator and the motor efficiency, wherein the allowable generating torque is determined based on the allowable generating power of the generator; In response to the fact that the product of the actual torque and the reducer speed ratio is less than or equal to the allowable power generation torque, the power generation demand is determined to be the power generation demand corresponding to the engine's idle speed, and is less than or equal to the maximum power generation demand corresponding to the idle speed. The generator is controlled to generate electricity based on the power demand.

2. The method according to claim 1, characterized in that, The method further includes: In response to the fact that the product of the actual torque and the reducer ratio is greater than the allowable generator torque, the torque requirement of the engine in the vehicle is determined as the target value, the allowable generator power is the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor is the allowable regenerative braking power of the motor, and the speed of the generator is the generator idle speed.

3. The method according to claim 1, characterized in that, The method further includes: In response to the fact that the product of the actual torque and the reducer ratio is less than or equal to the allowable generator torque, it is determined that the torque demand of the engine in the vehicle is greater than the target value, the allowable generator power is the product of the generator's minimum idle speed reserve power and the motor efficiency, the actual power of the motor is the allowable regenerative braking power of the motor, and the speed of the generator is the generator idle speed.

4. The method according to claim 1, characterized in that, The method further includes: Determine the quotient between the allowable charging power of the battery in the vehicle and the motor efficiency, and determine the difference between the quotient and the minimum idle speed reserve power of the generator; The minimum value between the difference between the quotient and the minimum idle speed reserved power and the external characteristic power of the motor is determined as the allowable regenerative power of the motor.

5. The method according to claim 1, characterized in that, The method further includes: Determine the product of the actual power of the motor and the motor efficiency; Determine the difference between the product of the actual power of the motor and the motor efficiency, and the allowable charging power of the battery in the vehicle; The minimum value between the difference and the external characteristic power of the generator is used to determine the allowable generating power of the generator.

6. The method according to claim 1, characterized in that, The method further includes: Determine the product of the allowable power generation capacity and the standard value; The allowable generating torque is determined by the quotient between the product of the allowable generating power and the standard value and the generator speed.

7. A vehicle, characterized in that, For performing the control method of the generator in the vehicle according to any one of claims 1 to 6.

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