Fuel cell automobile energy management method
By collecting real-time vehicle transmission gradient signals and adjusting fuel cell stack power based on coasting and braking feedback, the problem of unstable SOC value in fuel cell vehicles under complex operating scenarios is solved, protecting the performance and lifespan of the power battery and improving operating efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2026-03-31
AI Technical Summary
In complex operating scenarios, the SOC value of the power battery in fuel cell vehicles may be inaccurate, resulting in low SOC values and requiring the vehicle to be returned to the factory for debugging, which wastes time and money and affects the performance and lifespan of the power battery.
By collecting vehicle transmission gradient signals in real time, the terrain is determined and the power of the fuel cell stack is adjusted. The stack power is increased on uphill sections and adjusted on horizontal or downhill sections based on coasting and braking feedback. The stack power is optimized by combining throttle opening and SOC value, and a mapping relationship is established to stabilize the SOC value.
This avoids low SOC values in fuel cell vehicles due to their inability to adapt to complex operating scenarios, protects the performance and lifespan of the power battery, reduces the need for return-to-factory debugging, and improves operational efficiency.
Smart Images
Figure CN121756982A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of automotive energy control technology, specifically relating to an energy management method for fuel cell vehicles. Background Technology
[0002] Currently, some fuel cell vehicle manufacturers only conduct road tests on tracks within their factory premises before vehicles leave the factory. These tests operate under simple and comfortable, limited scenarios, making it impossible to assess the vehicle's performance in complex operating conditions. After leaving the factory, the vehicles may struggle to adapt to various complex operating scenarios, and the SOC (State of Charge) value of the power battery may not accurately adjust according to these scenarios. This can lead to frequent low SOC situations, requiring drivers to stop and recharge the vehicle or return it to the factory for reprogramming, wasting operating time and causing financial and time losses for users. Furthermore, it can negatively impact the performance and lifespan of the fuel cell system and the power battery. Summary of the Invention
[0003] To overcome one or more of the above-mentioned technical defects, the present invention provides an energy management method for fuel cell vehicles, which avoids the vehicle from having a low SOC value due to its inability to adapt to complex operating scenarios, and at the same time avoids the power battery from being overcharged due to receiving too much feedback and stack power, thereby protecting the performance and lifespan of the power battery.
[0004] To address the above problems, this invention provides an energy management method for fuel cell vehicles, comprising:
[0005] Real-time acquisition of slope signals from the vehicle's transmission to determine the vehicle's terrain.
[0006] When the vehicle is on an uphill section of road, the power of the fuel cell stack is adjusted to twice the current level.
[0007] When the vehicle is on a level road and / or downhill road, the fuel cell stack power is adjusted based on the vehicle's coasting feedback and braking feedback.
[0008] Furthermore, it also includes:
[0009] The power of the fuel cell stack is adjusted based on real-time data collected on throttle opening and the state of charge (SOC) value of the power battery.
[0010] Furthermore, the real-time acquisition of the vehicle's transmission gradient signal to determine the vehicle's terrain includes:
[0011] If the gradient signal meets the first preset condition within the first preset time, it is determined that the vehicle is on an uphill section.
[0012] If the vehicle is determined to be on an uphill section, and the gradient signal meets the second preset condition within a second preset time, the vehicle is considered to be on an uphill section; otherwise, the vehicle is considered to be on a downhill section.
[0013] Furthermore, when the vehicle is on a level road and / or downhill road, the process of collecting and adjusting the fuel cell stack power based on the vehicle's coasting feedback and braking feedback includes:
[0014] Establish a mapping relationship between coasting feedback and vehicle speed;
[0015] When the vehicle is on a level road and / or downhill road, the vehicle speed is collected in real time to obtain the corresponding coasting feedback;
[0016] If an increase in coasting feedback is detected, the stack power of the fuel cell is reduced.
[0017] If a decrease in coasting feedback is detected, the stack power of the fuel cell is increased.
[0018] Furthermore, when the vehicle is on a level road and / or downhill road, the process of collecting and adjusting the fuel cell stack power based on the vehicle's coasting feedback and braking feedback includes:
[0019] Establish a mapping relationship between brake feedback and vehicle brake pedal depth;
[0020] When the vehicle is on a level road and / or downhill road, the vehicle speed is collected in real time to obtain the corresponding braking feedback.
[0021] If an increase in braking feedback is detected, the stack power of the fuel cell is reduced.
[0022] If a decrease in braking feedback is detected, the stack power of the fuel cell is increased.
[0023] The present invention also provides a fuel cell vehicle energy management system, including a VCU, a fuel cell and a power battery. The VCU is connected to the fuel cell and the power battery respectively. The energy management is performed using the above-mentioned fuel cell vehicle energy management method to adjust the stack power of the fuel cell.
[0024] The present invention also provides a fuel cell vehicle, which adopts the above-mentioned fuel cell vehicle energy management method. When the vehicle is operating in a short-term operation scenario, it is equipped with a high-energy power battery and a fuel cell stack with a power of 80kW-120kW.
[0025] The present invention also provides a fuel cell vehicle, which adopts the above-mentioned fuel cell vehicle energy management method. When the vehicle is operating on a highway, it is equipped with a high-power power battery and a fuel cell stack with a power of 190kW or more.
[0026] The present invention also provides a fuel cell vehicle, which adopts the above-mentioned fuel cell vehicle energy management method. When the vehicle is operating in a mining scenario, it is equipped with a high-energy and high-power power battery and a fuel cell stack with a power of 150kW or more.
[0027] Compared with the prior art, the present invention has the following beneficial effects:
[0028] This invention discloses an energy management method for fuel cell vehicles, comprising: real-time acquisition of slope signals from the vehicle's transmission to determine the vehicle's terrain; when the vehicle is on an uphill section, controlling the fuel cell stack power to double the current level; when the vehicle is on a level section and / or a downhill section, acquiring and adjusting the fuel cell stack power based on the vehicle's coasting and braking feedback; and obtaining corresponding coasting and braking feedback in real time according to the vehicle's terrain, adjusting the fuel cell stack power accordingly to achieve a suitable level, thereby avoiding low SOC values due to the vehicle's inability to adapt to complex operating scenarios and preventing overcharging of the power battery due to excessive feedback and stack power, thus protecting the performance and lifespan of the power battery. Attached Figure Description
[0029] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, wherein:
[0030] Figure 1 This is a flowchart of the fuel cell vehicle energy management method described in Example 1;
[0031] Figure 2 The flowchart of step S3 of the fuel cell vehicle energy management method described in Example 1 Figure 1 ;
[0032] Figure 3 The flowchart of step S3 of the fuel cell vehicle energy management method described in Example 1 Figure 2 . Detailed Implementation
[0033] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.
[0034] Example 1
[0035] This embodiment discloses an energy management method for fuel cell vehicles, such as... Figure 1 ,include:
[0036] S1. Real-time acquisition of slope signals from the slope sensor in the vehicle's gearbox to determine the vehicle's terrain.
[0037] Specifically, step S1 includes:
[0038] If a slope signal of 120 indicates that the vehicle is in a horizontal position, then if the slope signal is greater than 120, the vehicle is considered to be on an uphill section; if the slope signal is less than 120, the vehicle is considered to be on a downhill section. The horizontal position, uphill section, and downhill section can be defined according to actual needs. In this embodiment, a slope signal of 120 indicates that the vehicle is in a horizontal position.
[0039] Considering the interference caused by factors such as the fluctuation of the slope sensor to the slope signal, the slope signal is filtered:
[0040] If the gradient signal is greater than 125 for 10 seconds, it is determined that the vehicle is on an uphill section of the road.
[0041] If a vehicle is determined to be on an uphill section and the gradient signal remains below 115 for no more than 10 seconds, the vehicle is considered to be on an uphill section. If the gradient signal remains below 115 for more than 10 seconds, the vehicle is considered to be on a downhill section.
[0042] S2. When the vehicle is on an uphill section, the power of the fuel cell stack is adjusted to twice the current level, at which point the vehicle downshifts to increase torque.
[0043] S3. When the vehicle is on a level road and / or downhill road, collect and adjust the fuel cell stack power based on the vehicle's coasting feedback and braking feedback.
[0044] Specifically, such as Figure 2 Step S3 includes:
[0045] Establish a mapping relationship between coasting feedback and vehicle speed; the greater the vehicle speed, the greater the coasting feedback.
[0046] When the vehicle is on a level road and / or downhill road, the vehicle speed is collected in real time to obtain corresponding coasting feedback.
[0047] If an increase in coasting feedback is detected, the power of the fuel cell stack is reduced; if a decrease in coasting feedback is detected, the power of the fuel cell stack is increased. This ensures both a stable SOC value for the power battery and prevents overcharging. Specifically, when the vehicle is on a level road, the maximum coasting feedback is 30% of the anti-drag torque borne by the rear axle; when the vehicle is on a downhill road, the maximum coasting feedback is 70% of the anti-drag torque borne by the rear axle.
[0048] Specifically, such as Figure 3 Step S3 also includes:
[0049] Establish a mapping relationship between brake feedback and brake pedal depth; the greater the brake pedal depth, the greater the brake feedback.
[0050] When the vehicle is on a level road and / or downhill road, the vehicle speed is collected in real time to obtain the corresponding braking feedback.
[0051] If an increase in braking feedback is detected, the power of the fuel cell stack is reduced; if a decrease in braking feedback is detected, the power of the fuel cell stack is increased. This ensures both a stable SOC value for the power battery and prevents overcharging. Specifically, when the vehicle is on a level road, the maximum braking feedback is 50% of the reverse drag torque borne by the rear axle; when the vehicle is on a downhill road, the maximum braking feedback is 90% of the reverse drag torque borne by the rear axle.
[0052] When the vehicle is on a downhill section, it receives greater coasting and braking feedback. At this time, the VCU controls the fuel cell stack power to the minimum allowable output power to avoid overcharging the power battery. In addition, since the maximum charging power is greater when the power battery's SOC value is lower, and the motor's regenerative power is also greater, more regenerative torque is provided to the motor, reducing the driver's need to frequently apply the brakes when going downhill. This also avoids the risk of brake pads overheating and temporarily failing, which could lead to serious safety accidents, caused by frequent braking during long downhill sections.
[0053] Optionally, the steps also include:
[0054] Based on real-time data collection of throttle opening and battery SOC, the fuel cell stack power is adjusted.
[0055] A mapping relationship is established between the throttle opening ratio (0-100%) and the fuel cell stack power (0-rated power). Specifically, in this embodiment, the throttle opening ratio and the fuel cell stack power have a positive functional relationship.
[0056] The throttle opening ratio is collected in real time to obtain the corresponding fuel cell stack power.
[0057] A correction factor is used to adjust the obtained fuel cell stack power, ensuring the SOC value of the power battery is within 50±10. This correction factor is generated based on the real-time SOC value of the power battery; when the real-time SOC value is less than 50%, the correction factor is greater than 1; when the real-time SOC value is greater than 50%, the correction factor is less than 1. This keeps the power battery in a shallow charge / shallow discharge state, protecting its performance and lifespan.
[0058] Specifically, the correction factor is generated based on the real-time SOC value of the power battery.
[0059] The correction coefficient is based on the SOC value of the power battery for PI control. In this embodiment, the optimal SOC value is set to 50. The result obtained by subtracting the current SOC value from 50 is multiplied by the coefficient kp and added to the integral of the coefficient ki (in this embodiment, kp = 0.1, ki = 0.01).
[0060] This invention obtains corresponding coasting feedback and braking feedback in real time based on the vehicle's terrain, and adjusts the fuel cell stack power according to the obtained coasting feedback and braking feedback to obtain a suitable power. This avoids the vehicle from having a low SOC value due to not being adapted to complex operating scenarios, and also avoids the power battery from being overcharged due to receiving too much feedback and stack power, thus protecting the performance and lifespan of the power battery.
[0061] Example 2
[0062] This embodiment discloses a fuel cell vehicle energy management system, including a VCU, a fuel cell, and a power battery. The VCU is connected to the fuel cell and the power battery respectively. Energy management is performed using the fuel cell vehicle energy management method described in Embodiment 1 to adjust the stack power of the fuel cell.
[0063] For specific implementation details, please refer to Example 1, which will not be repeated here.
[0064] Example 3
[0065] This embodiment discloses a fuel cell vehicle that employs the fuel cell vehicle energy management method described in Embodiment 1. When the vehicle operates under a short-term rotational operation scenario, it often needs to queue, causing it to idle for most of the time, resulting in a daily operating mileage of less than 200km. It is known that the battery does not require high-power operation, and frequent start-stop cycles of the fuel cell stack will affect its lifespan. Therefore, a high-energy power battery is configured to receive energy from the fuel cell for extended periods, and a fuel cell stack with a power output of 80kW-120kW is configured.
[0066] Example 4
[0067] This embodiment discloses a fuel cell vehicle that adopts the fuel cell vehicle energy management method described in Embodiment 1. When the vehicle is operating on a highway, the energy demand of the whole vehicle is large. Therefore, a high-power power battery and a fuel cell stack with a power of 190kW or more are configured.
[0068] Example 5
[0069] This embodiment discloses a fuel cell vehicle that adopts the fuel cell vehicle energy management method described in Embodiment 1. When the vehicle is operating in a mining environment, it will encounter many uphill and downhill sections. For long uphill sections, the power battery needs to continuously release high power to prevent the vehicle from running out of energy when it is halfway up the slope. For long downhill sections, the power battery needs to receive energy fed back from the vehicle and energy released by the fuel cell stack. Therefore, a high-energy and high-power power battery and a fuel cell stack with a power of 150kW or more are configured.
[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.
Claims
1. A fuel cell vehicle energy management method, characterized by, The method comprises the following steps: Real-time acquisition of the slope signal of the vehicle transmission to determine the terrain where the vehicle is located; When the vehicle is on an uphill road section, the power of the fuel cell stack is controlled to be twice the current value; When the vehicle is on a horizontal road section and / or a downhill road section, the power of the fuel cell stack is adjusted based on the coasting feedback and braking feedback of the vehicle.
2. The fuel cell vehicle energy management method according to claim 1, characterized by, Further comprising: Based on the real-time acquisition of the accelerator opening degree and the SOC value of the power battery, the power of the fuel cell stack is adjusted.
3. The fuel cell vehicle energy management method of claim 1, wherein, The real-time acquisition of the slope signal of the vehicle transmission to determine the terrain where the vehicle is located comprises: If the slope signal meets the first preset condition within the first preset time, it is determined that the vehicle is on an uphill road section; If it is determined that the vehicle is on an uphill road section, and the slope signal meets the second preset condition within the second preset time, it is considered that the vehicle remains on the uphill road section, otherwise it is determined that the vehicle is on a downhill road section.
4. The fuel cell vehicle energy management method of claim 1 wherein, The adjustment of the power of the fuel cell stack based on the coasting feedback and braking feedback of the vehicle when the vehicle is on a horizontal road section and / or a downhill road section comprises: Establishing a mapping relationship between the coasting feedback and the vehicle speed; Real-time acquisition of the vehicle speed when the vehicle is on a horizontal road section and / or a downhill road section to obtain the corresponding coasting feedback; If the coasting feedback is detected to increase, the power of the fuel cell stack is controlled to decrease; If the coasting feedback is detected to decrease, the power of the fuel cell stack is controlled to increase.
5. The fuel cell vehicle energy management method of claim 1 wherein, The adjustment of the power of the fuel cell stack based on the coasting feedback and braking feedback of the vehicle when the vehicle is on a horizontal road section and / or a downhill road section comprises: Establishing a mapping relationship between the braking feedback and the depth of the vehicle brake pedal; Real-time acquisition of the vehicle speed when the vehicle is on a horizontal road section and / or a downhill road section to obtain the corresponding braking feedback; If the braking feedback is detected to increase, the power of the fuel cell stack is controlled to decrease; If the braking feedback is detected to decrease, the power of the fuel cell stack is controlled to increase.
6. A fuel cell vehicle energy management system characterized by comprising: The fuel cell vehicle energy management method comprises a VCU, a fuel cell and a power battery, the VCU is connected with the fuel cell and the power battery, and the energy management is performed by using the fuel cell vehicle energy management method of any one of claims 1-5 to adjust the power of the fuel cell stack.
7. A fuel cell vehicle characterized by comprising: When the operation scenario of the vehicle is reverse short operation, a large energy type power battery and a fuel cell stack with a power of 80kW-120kW are configured by using the fuel cell vehicle energy management method of any one of claims 1-5.
8. A fuel cell vehicle characterized by comprising: When the operation scenario of the vehicle is high-speed road section operation, a large power type power battery and a fuel cell stack with a power of more than 190kW are configured by using the fuel cell vehicle energy management method of any one of claims 1-5.
9. A fuel cell vehicle characterized by comprising: When the operation scenario of the vehicle is mine operation, a large energy type and large power type power battery and a fuel cell stack with a power of more than 150kW are configured by using the fuel cell vehicle energy management method of any one of claims 1-5.