Residual power utilization method of range-extended commercial vehicle

Abstract

The invention discloses a residual power utilization method of an extended-range commercial vehicle, relates to the technical field of energy recovery of commercial vehicles, and solves the technical problems of hub heating, brake failure and reduced safety caused by long-time brake of an existing extended-range commercial vehicle. The electric quantity of a battery of the extended-range commercial vehicle in the long downhill process is obtained, when the electric quantity of the battery is in a fully-charged state in the long downhill process, charging of the battery by a driving motor is cut off, the electric quantity recycled by the driving motor is transmitted to a power generator, and an engine is reversely dragged through the power generator; and when the engine is reversely dragged, the engine opens an in-cylinder brake. The purpose of consuming electricity can be achieved, and the safety is improved.

Description

Technical Field

[0001] This invention relates to the field of energy recovery technology for commercial vehicles, and more specifically, to a method for utilizing the residual power of a range-extended commercial vehicle. Background Technology

[0002] Range-extended commercial vehicles are equipped with a range extender and a drive motor. The range extender consists of an engine and a generator with a starter function. The drive motor has driving and energy recovery functions. The power batteries used in range-extended tractor vehicles are mostly in the range of tens to 120 degrees Celsius. When encountering long downhill sections, the drive motor may continuously charge the battery until it is fully charged. Then the drive motor can no longer charge the battery, and the energy recovered by the drive motor cannot be used. This is equivalent to losing the regenerative braking force of the drive motor (no braking). At this time, it is necessary to use the wheel hub brakes. However, the wheel hub brakes can only be used for a short time. Prolonged braking will cause the wheel hubs to overheat, brake failure, and reduced safety. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method for utilizing the residual power of a range-extended commercial vehicle, which addresses the shortcomings of the existing technology and solves the problem of wheel hub overheating, brake failure, and reduced safety caused by prolonged braking in existing range-extended commercial vehicles.

[0004] The present invention discloses a method for utilizing the residual power of a range-extended commercial vehicle. The method involves obtaining the battery charge of the range-extended commercial vehicle during a long downhill process. When the battery charge is fully charged during the long downhill process, the charging of the battery by the drive motor is cut off, and the power recovered by the drive motor is transmitted to the generator, which then tows the engine. While towing the engine, the engine engages its cylinder brake.

[0005] As a further improvement, when the in-cylinder brake is engaged, the maximum braking power of the engine is set, the regenerative braking power of the drive motor is obtained, and the regenerative braking power of the drive motor is compared with the maximum braking power of the engine. When the regenerative braking power of the drive motor is less than or equal to the maximum braking power of the engine, the first braking mode is triggered; when the regenerative braking power of the drive motor is greater than the maximum braking power of the engine, the second braking mode is triggered.

[0006] Furthermore, the first braking method involves driving a generator to use the power recovered by a drive motor to tow the engine backwards.

[0007] Furthermore, the second braking method involves obtaining the tire braking power by subtracting the recovery power of the drive motor from the maximum braking power of the engine, driving the generator to tow the engine with the maximum braking power of the engine, and simultaneously applying wheel hub braking based on the tire braking power.

[0008] Furthermore, when the in-cylinder brake is engaged, the brake pedal opening is acquired, and the engine speed and throttle opening are calibrated and adjusted based on the brake pedal opening and the regenerative braking power of the drive motor. The engine is then controlled based on the adjusted engine speed and throttle opening.

[0009] Beneficial effects

[0010] The advantages of this invention are: This invention obtains the battery charge of a range-extended commercial vehicle during a long downhill descent. When the battery is fully charged during the descent, the drive motor's charging of the battery is cut off, and the energy recovered by the drive motor is transferred to the generator. The generator then tows the engine. While towing the engine, the engine engages its in-cylinder brakes to increase drag resistance, converting the recovered energy into other forms of consumption. This consumes a portion of the energy generated by the drive motor, thereby reducing brake usage and improving driving safety. Attached Figure Description

[0011] Figure 1 This is a flowchart of the method for utilizing the residual power of a range-extended commercial vehicle according to the present invention; Figure 2 This is a flowchart of the engine in-cylinder braking control method of the present invention; Figure 3 This is a simplified structural diagram of the residual power utilization system for the range-extended commercial vehicle of the present invention.

[0012] Among them: 1-engine, 2-generator, 3-battery, 4-drive motor, 5-drive wheel. Detailed Implementation

[0013] The present invention will be further described below with reference to embodiments, but this does not constitute any limitation on the present invention. Any limited modifications made by any person within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0014] See Figures 1-3 The present invention provides a method for utilizing the residual power of a range-extended commercial vehicle, such as... Figure 1 As shown, the method involves obtaining the battery power of the range-extended commercial vehicle 3 during a long downhill slope. When the battery power of the battery 3 is fully charged during the long downhill slope, the charging of the battery 3 by the drive motor 4 is cut off, and the power recovered by the drive motor 4 is transmitted to the generator 2. The generator 2 then tows the engine 1. When towing the engine 1, the engine 1 engages the in-cylinder brake to increase the drag resistance. The recovered power is converted into other forms of consumption, thereby consuming the recovered power and consuming a portion of the power generated by the drive motor 4. This reduces the use of brakes and improves driving safety.

[0015] When the in-cylinder braking is engaged, the engine's maximum braking power is set, the regenerative braking power of the drive motor is obtained, and the regenerative braking power of the drive motor is compared with the engine's maximum braking power. When the regenerative braking power of the drive motor is less than or equal to the engine's maximum braking power, the first braking mode is triggered; when the regenerative braking power of the drive motor is greater than the engine's maximum braking power, the second braking mode is triggered.

[0016] The first braking method is to drive the generator 2 to use the power recovered by the drive motor to tow the engine 1 backward.

[0017] like Figure 2 As shown, when the in-cylinder brake is engaged and an in-cylinder brake signal is received, the brake pedal opening is acquired. Based on the brake pedal opening and the regenerative braking power of the drive motor, the engine speed and throttle opening are calibrated and adjusted. The engine 1 is controlled based on the adjusted engine speed and throttle opening. When the regenerative braking power of the drive motor changes due to the adjustment of the engine speed and throttle opening, the engine speed and throttle opening are calibrated and adjusted again based on the brake pedal opening and the regenerative braking power of the drive motor, thereby achieving closed-loop adjustment of the adjusted engine speed and throttle opening.

[0018] When engaging the in-cylinder brake, the engine's maximum idle speed must not be exceeded; this speed can be selected. Generally, higher speeds result in greater braking power. The braking power distribution can be adjusted based on the brake pedal opening, prioritizing engine braking during reversing. If engine braking during reversing doesn't consume enough energy, some energy will be allocated to wheel hub braking.

[0019] When the regenerative braking power of the drive motor exceeds the maximum braking power of the engine, the second braking mode is triggered.

[0020] The second braking method is to obtain the tire braking power by subtracting the recovery power of the drive motor from the maximum braking power of the engine, and drive the generator 2 to reverse the engine 1 with the maximum braking power of the engine, while simultaneously applying wheel hub braking according to the tire braking power.

[0021] In range extenders, the engine is generally not equipped with a starter motor; instead, the generator tows the engine to start it. Utilizing this characteristic, during long downhill descents, if the battery is fully charged, it can continue to drive the generator (achieving a braking effect), while the generator tows the engine (engaging cylinder braking and exhaust braking), thus consuming electricity and improving safety.

[0022] During long downhill driving, if battery 3 is fully charged, it can continue to drive generator 2, which in turn tow engine 1. Similarly, if battery 3 is fully charged during long downhill driving, it can continue to drive generator 2 (achieving a braking effect), while generator 2 tows engine 1 (activating cylinder braking and exhaust braking), thereby consuming electricity and improving safety.

[0023] Specifically, when the regenerative braking power of the drive motor is less than or equal to the engine's maximum braking power, all the regenerative braking power is used for engine braking. When the regenerative braking power of the drive motor is greater than the engine's maximum braking power, the regenerative braking power is allocated as: drive motor regenerative braking power - engine maximum braking power = tire brake braking power.

[0024] Here is a specific example: Assuming the maximum braking power of the towing engine is 150kW, and the brakes generate 150kW of braking force, then all of it can be used for braking the towing engine. If the brakes generate 200kW of braking force, then the engine consumes 150kW, and the remaining 50kW of braking force is consumed by the wheel hub brakes.

[0025] Numerous factors influence engine braking performance, encompassing engine characteristics and vehicle driving conditions. Vehicle speed, load, and center of gravity distribution also play a role; engine braking faces greater challenges at higher speeds and heavier loads. Therefore, this invention also provides a method for setting the maximum engine braking power. This method involves obtaining an initial maximum engine braking power, acquiring the vehicle's real-time speed and engine braking torque, calibrating an engine braking power correction value based on the real-time speed and braking torque, and adding the initial maximum engine braking power to the correction value to obtain the target maximum engine braking power. Incorporating this target maximum engine braking power into the aforementioned residual power method for range-extended commercial vehicles achieves constraint on the engine's maximum braking power, thereby improving safety.

[0026] Down Figure 3 This is a simplified structural diagram of the residual power utilization system for a range-extended commercial vehicle according to the present invention. The system includes an engine 1, a generator 2, a battery 3, a drive motor 4, and drive wheels 5. The engine 1 is connected to the generator 2, the generator 2 is connected to the drive motor 4, the battery 3 is connected between the drive motor 4 and the generator 2, and the drive motor 4 is connected to the two drive wheels 5 of the vehicle. The drive wheels 5 are the core transmission components for realizing power output. The drive motor 4 is used to provide power to the drive wheels 5 and can also be used for energy recovery from the drive wheels 5.

[0027] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention, and these will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A method for utilizing the residual power of a range-extended commercial vehicle, characterized in that, The method is as follows: the battery (3) of the range-extended commercial vehicle is obtained during the long downhill process. When the battery (3) is fully charged during the long downhill process, the charging of the battery (3) by the drive motor (4) is cut off, and the power recovered by the drive motor (4) is transmitted to the generator (2). The generator (2) is used to tow the engine (1). When towing the engine (1), the engine (1) engages the cylinder brake.

2. The method for utilizing residual power in a range-extended commercial vehicle according to claim 1, characterized in that, When the in-cylinder brake is engaged, the maximum braking power of the engine is set, the regenerative braking power of the drive motor is obtained, and the regenerative braking power of the drive motor is compared with the maximum braking power of the engine. When the regenerative braking power of the drive motor is less than or equal to the maximum braking power of the engine, the first braking mode is triggered; when the regenerative braking power of the drive motor is greater than the maximum braking power of the engine, the second braking mode is triggered.

3. The method for utilizing residual power in a range-extended commercial vehicle according to claim 2, characterized in that, The first braking method is to drive the generator (2) to drive the motor to recover power and tow the engine (1) backward.

4. The method for utilizing residual power in a range-extended commercial vehicle according to claim 2, characterized in that, The second braking method is to obtain the tire braking power by subtracting the recovery power of the drive motor from the maximum braking power of the engine, and drive the generator (2) to reverse the engine (1) with the maximum braking power of the engine, while simultaneously applying wheel hub braking according to the tire braking power.

5. The method for utilizing residual power in a range-extended commercial vehicle according to claim 1, characterized in that, When the in-cylinder brake is engaged, the brake pedal opening is obtained, and the speed and throttle opening are calibrated and adjusted according to the brake pedal opening and the regenerative braking power of the drive motor. The engine is controlled according to the adjusted speed and throttle opening (1).

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