Hybrid mode control method for extended-range automobile

Abstract

The invention discloses a hybrid mode control method for an extended-range automobile. At least a pure electric mode, a starting mode, a dragging mode and the like are configured for hybrid control. The control process comprises the steps that when the following conditions are met at the same time, the pure electric mode is allowed to enter the starting mode, specifically, high-voltage read exists, the rotating speed of an engine is low, and the range extender starting requirement exists; when the following conditions are met at the same time, the starting mode is allowed to enter the dragging mode: high-pressure read, lower engine rotating speed and range extender dragging requirement exist; wherein the conditions for judging the existence of the dragging demand are as follows: when a high-voltage read mode is a forward gear in a pure electric mode, the acceleration of the vehicle is relatively high, and the SOC is close to full power, energy recovery is performed; and when the following conditions are met at the same time, the dragging mode is allowed to enter the starting mode: high-voltage read exists, and the range extender starting requirement exists. The invention provides a comprehensive and abundant hybrid power control framework and mode switching mechanism which are obviously superior to the current hybrid power mode control scheme.

Description

Technical Field

[0001] The present invention relates to the technical field of extended-range vehicles, and in particular to a hybrid mode control method for an extended-range vehicle. Background Art

[0002] In order to reduce the pressure on the brake system and prevent the brake pads from overheating, traditional vehicles usually put the car in a suitable gear and use engine braking to assist braking when driving on a long downhill slope. However, for extended-range vehicles, the engine and drive are decoupled, so the previous method cannot be used for auxiliary braking.

[0003] At present, the hybrid control mode of most extended-range vehicles is not perfect. According to the existing mode, there are driving risks under certain conditions. For example, in a long downhill condition, if the battery is fully charged, energy recovery cannot be performed, and the vehicle speed can only be controlled by the vehicle's braking system. Therefore, based on this long downhill condition, there is a risk of brake pad overheating and failure. Summary of the invention

[0004] In view of the above, the present invention aims to provide a hybrid mode control method for an extended-range vehicle to solve the above-mentioned problems.

[0005] The technical solution adopted by the present invention is as follows:

[0006] The present invention provides a hybrid mode control method for a range-extended vehicle, wherein the hybrid mode includes: a pure electric mode, a range-extender start mode, and a range-extender drag mode;

[0007] When it is detected that the following conditions are met at the same time, it is allowed to enter the range extender start mode from the pure electric mode: the vehicle driving high voltage conditions are ready, the engine speed is less than the corresponding set threshold, and there is a need to start the range extender;

[0008] When it is detected that the following conditions are met at the same time, it is allowed to enter the range extender towing mode from the range extender start mode: the vehicle driving high voltage condition is ready, the engine speed is less than the corresponding set threshold, and there is a range extender towing demand; among which, the conditions for determining the existence of the towing demand are: when the vehicle driving high voltage condition is ready, the gear position in the pure electric mode is the forward gear, the vehicle acceleration is greater than the corresponding set threshold, and the SOC is characterized as close to full charge according to the established threshold, energy recovery is performed;

[0009] When it is detected that the following conditions are met at the same time, it is allowed to enter the range extender start mode from the range extender towing mode: the vehicle driving high voltage conditions are ready and there is a need to start the range extender.

[0010] In at least one of the possible implementations, the hybrid mode further includes: a range extender shutdown mode;

[0011] When any of the following conditions is detected, it is allowed to enter the range extender shutdown mode from the range extender towing mode: the vehicle driving high voltage conditions are not ready, the generator is not enabled, and there is no range extender towing demand.

[0012] In at least one possible implementation, the control method further includes:

[0013] When any of the following conditions is detected, it is allowed to enter the range extender stop mode from the range extender start mode: the vehicle driving high voltage conditions are not ready, the generator is not enabled, the engine start fails, and there is no range extender start demand.

[0014] In at least one possible implementation, the control method further includes:

[0015] When any of the following conditions is detected, it is allowed to enter the pure electric mode from the range extender shutdown mode: the vehicle's high voltage driving conditions are not ready, the generator is not enabled, the engine is not running and the engine speed is less than the corresponding set threshold.

[0016] In at least one of the possible implementations, the hybrid mode further includes: a series mode;

[0017] When it is detected that the following conditions are met at the same time, it is allowed to enter the series mode from the range extender start mode: the vehicle driving high voltage conditions are ready, the generator is enabled, there is a demand to start the range extender, and the range extender is started successfully.

[0018] In at least one possible implementation, the control method further includes:

[0019] When any of the following conditions is detected, it is allowed to enter the range extender shutdown mode from the series mode: the vehicle driving high voltage conditions are not ready, the generator is not enabled, and there is no need to start the range extender.

[0020] In at least one possible implementation, the presence of a range extender startup requirement is determined based on any of the following dimensions: SOC status, battery discharge power status, external request status, battery protection status, and parking power generation status.

[0021] In at least one possible implementation manner, the external request state includes: a request for heating in the cockpit.

[0022] Compared with the prior art, the main design concept of the present invention is to configure at least a pure electric mode, a range extender start mode, and a range extender drag mode for hybrid control; thus, the control process includes allowing entry from the pure electric mode to the start mode when the following conditions are met at the same time: driving high voltage ready, engine speed is less than a threshold, and there is a range extender start demand; when the following conditions are met at the same time, it is allowed to enter the drag mode from the start mode: driving high voltage ready, engine speed is less than a threshold, and there is a range extender drag demand; wherein, the condition for determining the existence of the drag demand is: when the driving high voltage is ready, the gear position in the pure electric mode is the forward gear, the acceleration of the vehicle is greater than the threshold, and the SOC is characterized as close to full power according to the established threshold, energy recovery is performed; and when the following conditions are met at the same time, it is allowed to enter the start mode from the drag mode: driving high voltage ready, and there is a range extender start demand. The present invention provides a comprehensive and rich hybrid control architecture and mode switching control mechanism, which is significantly better than the current hybrid mode control scheme. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described below with reference to the accompanying drawings, in which:

[0024] Figure 1 A schematic diagram of the mode flow of the hybrid mode control architecture of a range-extended vehicle provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0025] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein 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 accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0026] The present invention proposes an embodiment of a hybrid mode control method for a range-extended vehicle. Specifically, Figure 1 As shown, the hybrid control modes include: pure electric mode, series mode, range extender start mode, range extender stop mode, and in particular, also include range extender drag mode.

[0027] In the above control mode architecture, the present invention proposes the following conversion control strategy between different modes.

[0028] When entering the start mode from the pure electric mode (corresponding to Figure 1 Arrow ①) The following conditions must be met simultaneously: (1) The vehicle high pressure is Ready (the vehicle high pressure condition is ready for driving); (2) The engine speed is less than the corresponding set threshold; (3) The range extender start demand judgment is set to 1.

[0029] When entering drag mode from startup mode (corresponding to Figure 1 Arrow ②) requires the following conditions to be met simultaneously: (1) the vehicle high pressure is ready; (2) the engine speed is less than the corresponding set threshold; (3) the range extender drag demand determination is set to 1.

[0030] For the case where the drag demand judgment is set to 1, to expand on this, when the vehicle is in the high-voltage Ready state, the pure electric mode is in the forward gear, the vehicle acceleration is greater than the corresponding set threshold, and the SOC is determined to be close to full charge according to the established threshold, if energy recovery is performed at this time, it is necessary to enter the range extender drag mode proposed in this embodiment, and the range extender drag demand state position 1. By allowing this mode to be activated, the drive motor can continuously recover energy to reduce the pressure on the vehicle's braking system.

[0031] It should be pointed out here that in the towing mode, the generator is used to drive the engine to idle, and the engine is controlled not to perform fuel injection and ignition, thereby consuming the electric energy generated by the drive motor through energy recovery, thereby preventing the battery from being overcharged in a high SOC state, and at the same time, the drive motor energy recovery can reduce the pressure on the brake system. That is, through the towing mode proposed by the present invention, when the battery is nearly fully charged and in a long downhill condition, the range extender towing mode can consume electricity, allowing the drive motor to continue to recover energy, reducing the risk of brake pad overheating caused by continuous braking of the vehicle.

[0032] Continuing from the previous article, when entering the start mode from the drag mode (corresponding to Figure 1 Arrow ⑦), the following conditions must be met simultaneously: (1) the vehicle high voltage is Ready; and (2) the range extender start demand determination is set to 1.

[0033] In addition, in other embodiments of the present invention, when entering the series mode from the startup mode (corresponding to Figure 1 Arrow ③) requires the following conditions to be met simultaneously: (1) the vehicle high voltage is ready; (2) the generator is enabled; (3) the range extender start requirement is set to 1; (4) the range extender is started successfully.

[0034] Then, when entering the stop mode from the series mode (corresponding to Figure 1 Arrow ④) requires that any of the following conditions be met: (1) the vehicle is not in high voltage Ready state; or (2) the generator is not enabled; or (3) the range extender start demand determination is set to 0.

[0035] Or, when entering the stop mode from the start mode (corresponding to Figure 1 Arrow ⑥) requires any of the following conditions to be met: (1) the vehicle is not high voltage ready; or (2) the generator is not enabled; or (3) the engine starts failed; or (4) the range extender start demand determination is set to 0.

[0036] In particular, corresponding to the above embodiments, the present invention also relates to the case of entering the stop mode from the drag mode, and thus it is proposed that when any of the following conditions is detected, it is allowed to enter the stop mode from the drag mode (corresponding to Figure 1 Arrow⑧): (1) The vehicle is not high voltage ready; or (2) the generator is not enabled; or (3) the range extender traction demand determination is set to 0.

[0037] Then, when entering the pure electric mode from the stop mode (corresponding to Figure 1 Arrow ⑤) requires that any of the following conditions be met: (1) the vehicle is not in high voltage Ready state; or (2) the generator is not enabled; or (3) the engine is not running and the engine speed is less than the corresponding set threshold.

[0038] Finally, it can also be mentioned that for the situation involving the start requirement state position 1 of the range extender in the aforementioned embodiments, the present invention proposes in some embodiments that when any of the following judgment conditions is met, it indicates that the range extender needs to be started, that is, the start requirement state position 1.

[0039] (1) Determination based on SOC: The vehicle speed is higher than the corresponding set threshold and the SOC is lower than the corresponding set threshold, or the SOC is lower than the emergency low threshold.

[0040] (2) Determination based on insufficient battery discharge power: When the vehicle speed is higher than the corresponding set threshold and the battery discharge power is less than the battery discharge power for a period of time.

[0041] (3) Determination based on external requests: when there is a request for engine warm-up or post-processing ignition and the power battery SOC is less than (target SOC-preset threshold); or a carbon canister desorption request; or a cabin heating request; or a battery cell heating request, etc. Therefore, it can be additionally added that for the range-extending technology route with small batteries and mainly oil, when the driver has a heating demand, the range extender can be started to use the engine water temperature to heat the cabin without the need to specifically configure PTC.

[0042] (4) Based on battery protection judgment: the temperature of the single cell is too low and the SOC is lower than the corresponding set threshold; or the temperature of the single cell is too high; or the voltage of the single cell is lower than the corresponding set threshold; or the battery discharge power is lower than the corresponding set threshold; or the battery charging power is lower than the corresponding set threshold.

[0043] (5) Based on parking power generation judgment: when the vehicle speed is 0, the throttle is greater than the corresponding set threshold, the gear is in neutral, and the SOC is lower than the corresponding set threshold.

[0044] In summary, the main design concept of the present invention is to configure at least a pure electric mode, a range extender start mode, and a range extender drag mode for hybrid control; thus, the control process includes allowing entry from the pure electric mode to the start mode when the following conditions are met at the same time: driving high voltage ready, the engine speed is less than the threshold, and there is a range extender start demand; when the following conditions are met at the same time, it is allowed to enter the drag mode from the start mode: driving high voltage ready, the engine speed is less than the threshold, and there is a range extender drag demand; wherein, the condition for determining the existence of the drag demand is: when the driving high voltage is ready, the gear position in the pure electric mode is the forward gear, the acceleration of the vehicle is greater than the threshold, and the SOC is characterized as close to full power according to the established threshold, energy recovery is performed; and when the following conditions are met at the same time, it is allowed to enter the start mode from the drag mode: driving high voltage ready, and there is a range extender start demand. The present invention provides a comprehensive and rich hybrid control architecture and mode switching control mechanism, which is significantly better than the current hybrid mode control scheme.

[0045] If the expressions expressing orientation are mentioned in the embodiments of the present invention, they are relative concepts based on the embodiments. In addition, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, a and b, a and c, b and c, or a and b and c, wherein a, b, c can be single or multiple.

[0046] The above describes in detail the structure, features and effects of the present invention based on the embodiments shown in the drawings, but the above is only a preferred embodiment of the present invention. It should be noted that the technical features involved in the above embodiments and their preferred methods can be reasonably combined and matched into a variety of equivalent schemes by those skilled in the art without departing from or changing the design ideas and technical effects of the present invention; therefore, the present invention is not limited to the scope of implementation shown in the drawings, and all changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the specification and drawings, should be within the protection scope of the present invention.

Claims

1. A hybrid mode control method for a range-extended vehicle, characterized in that: Hybrid modes include: pure electric mode, range extender start mode, and range extender drag mode; When it is detected that the following conditions are met at the same time, it is allowed to enter the range extender start mode from the pure electric mode: the vehicle driving high voltage conditions are ready, the engine speed is less than the corresponding set threshold, and there is a need to start the range extender; When it is detected that the following conditions are met at the same time, it is allowed to enter the range extender towing mode from the range extender start mode: the vehicle driving high voltage condition is ready, the engine speed is less than the corresponding set threshold, and there is a range extender towing demand; among which, the conditions for determining the existence of the towing demand are: when the vehicle driving high voltage condition is ready, the gear position in the pure electric mode is the forward gear, the vehicle acceleration is greater than the corresponding set threshold, and the SOC is characterized as close to full charge according to the established threshold, energy recovery is performed; When it is detected that the following conditions are met at the same time, it is allowed to enter the range extender start mode from the range extender towing mode: the vehicle driving high voltage conditions are ready and there is a need to start the range extender.

2. The method for controlling the hybrid mode of a range-extended vehicle according to claim 1, characterized in that: Hybrid modes also include: range extender shutdown mode; When any of the following conditions is detected, it is allowed to enter the range extender shutdown mode from the range extender towing mode: the vehicle driving high voltage conditions are not ready, the generator is not enabled, and there is no range extender towing demand.

3. The method for controlling the hybrid mode of an extended-range vehicle according to claim 2, characterized in that: The control method further comprises: When any of the following conditions is detected, it is allowed to enter the range extender stop mode from the range extender start mode: the vehicle driving high voltage conditions are not ready, the generator is not enabled, the engine start fails, and there is no range extender start demand.

4. The method for controlling the hybrid mode of a range-extended vehicle according to claim 2, characterized in that: The control method further comprises: When any of the following conditions is detected, it is allowed to enter the pure electric mode from the range extender shutdown mode: the vehicle's high voltage driving conditions are not ready, the generator is not enabled, the engine is not running and the engine speed is less than the corresponding set threshold.

5. The method for controlling the hybrid mode of a range-extended vehicle according to claim 1, characterized in that: Hybrid modes also include: Series mode; When it is detected that the following conditions are met at the same time, it is allowed to enter the series mode from the range extender start mode: the vehicle driving high voltage conditions are ready, the generator is enabled, there is a demand to start the range extender, and the range extender is started successfully.

6. The method for controlling the hybrid mode of a range-extended vehicle according to claim 5, characterized in that: The control method further comprises: When any of the following conditions is detected, it is allowed to enter the range extender shutdown mode from the series mode: the vehicle driving high voltage conditions are not ready, the generator is not enabled, and there is no need to start the range extender.

7. The hybrid mode control method for a range-extended vehicle according to any one of claims 1 to 6, characterized in that: The presence of a range extender start requirement is determined based on any of the following dimensions: SOC status, battery discharge power status, external request status, battery protection status, and parking power generation status.

8. The method for controlling the hybrid mode of a range-extended vehicle according to claim 7, characterized in that: The external request state includes: a cockpit heating request.

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