A fuel cell commercial vehicle long time idle protection control method and system

Abstract

The present application relates to the technical field of new energy vehicle control, and specifically provides a long-time idle speed protection control method and system for a fuel cell commercial vehicle, which comprises the following steps: collecting fuel cell output power, vehicle accessory load power and power battery SOC; determining whether there is fuel cell surplus power; if there is fuel cell surplus power and the power battery SOC is less than a set upper threshold, absorbing the fuel cell surplus power by the power battery; when the power battery SOC is not less than the set upper threshold, increasing the operating power of a cold machine and converting the fuel cell surplus power into cold energy, and storing the cold energy by a phase change cold storage device. The present application preferentially uses the power battery to absorb the fuel cell surplus power when the vehicle is idling, and when the power battery SOC is not less than the set upper threshold, increases the operating power of the cold machine and converts the fuel cell surplus power into cold energy, and stores the cold energy by the phase change cold storage device, thereby realizing the joint storage and scheduling of electric energy and cold energy.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle control technology, specifically to the field of energy management and fuel cell system protection control technology for fuel cell commercial vehicles, and in particular to a long-term idling protection control method and system for fuel cell commercial vehicles based on electric-cold energy storage synergy for application scenarios such as cold chain transportation and logistics distribution. Background Technology

[0002] During cold chain transportation and logistics distribution, vehicles are often parked or idling for extended periods while loading, unloading, or waiting in line. At these times, the vehicles have virtually no need for driving power, but accessories such as refrigeration units, air conditioners, air compressors, circulating water pumps, and control systems still need to operate continuously. Therefore, the entire vehicle still requires a stable power supply.

[0003] Fuel cell systems cannot maintain efficient and stable operation at arbitrarily low power levels. To maintain operating conditions such as stack temperature, air supply, hydrogen circulation, and cooling circulation, fuel cells typically need to maintain a certain stable output power. Under prolonged idling conditions, this stable output power may exceed the actual electrical demand of vehicle accessories, thus generating excess electrical energy.

[0004] Existing technologies typically address this by reducing the fuel cell's output power, starting and stopping the fuel cell, or using a power battery to absorb excess electrical energy. To keep the fuel cell operating within a relatively efficient and stable range, the power battery is usually used to absorb its excess electrical energy.

[0005] How to maintain the fuel cell in a highly efficient and stable operating range during prolonged idling, while also effectively transferring, storing, and utilizing excess energy from the fuel cell when the power battery's state of charge (SOC) is high, is a problem that existing technologies need to solve. Based on this, this invention proposes a method and system for long-term idling protection and control of fuel cell commercial vehicles based on electric-cooled energy storage synergy. Summary of the Invention

[0006] Based on this, in order to achieve the joint storage and scheduling of electrical energy and cold energy, the present invention provides a method and system for recovering and utilizing waste heat from fuel cells based on thermoelectric power generation, the specific technical solution of which is as follows: A method for protecting and controlling the long-term idling speed of a fuel cell commercial vehicle includes the following steps: S1 determines whether the vehicle is idling. If so, it collects the fuel cell output power, the vehicle accessory load power, and the power battery SOC. S2, determine whether there is excess power in the fuel cell based on the fuel cell output power and the load power of the vehicle accessories; S3: If there is excess power in the fuel cell and the SOC of the power battery is less than the set upper limit threshold, the excess power of the fuel cell is absorbed by the power battery. S4: When the SOC of the power battery is not less than the set upper limit threshold, the electric-cold energy storage collaborative mode is activated to increase the operating power of the chiller and convert the surplus electrical energy of the fuel cell into cold energy, which is then stored through the phase change cold storage device.

[0007] The described long-term idling protection control method for fuel cell commercial vehicles prioritizes the use of the power battery to absorb the excess power of the fuel cell when the vehicle is idling. When the SOC of the power battery is not less than the set upper limit threshold, the electric-cold energy storage collaborative mode is activated to increase the operating power of the chiller and convert the excess electrical energy of the fuel cell into cold energy. The cold energy is stored through a phase change cold storage device, realizing the joint storage and scheduling of electrical energy and cold energy.

[0008] Preferably, step S4 further includes: in the electric-cold energy storage collaborative mode, reducing the temporary temperature setting value of the cargo compartment according to the allowable temperature range of the cargo inside the vehicle; when the cold storage capacity of the phase change cold storage device reaches the upper limit and the SOC of the power battery is not less than the set upper limit threshold, reducing the output power of the fuel cell and entering a low power holding state.

[0009] Preferably, the method for long-term idling protection control of fuel cell commercial vehicles further includes the following steps: S5 controls the phase change cold storage device to release stored cold energy when the vehicle exits the idling condition, assisting in the cooling of the cargo box and reducing the operating load of the refrigeration unit.

[0010] Preferably, in step S1, determining whether the vehicle is in an idling condition specifically includes: if the vehicle speed is zero and the duration exceeds a preset idling determination time threshold, and the drive motor power demand is less than a preset power demand threshold, then the vehicle is determined to be in an idling condition.

[0011] Preferably, the method for obtaining the temporary temperature setpoint includes the following steps: S41. Determine whether there is a risk of low-temperature damage to the goods. If so, obtain the predicted duration of idling and the low-temperature tolerance time threshold of the goods. Compare the predicted duration of idling and the low-temperature tolerance time threshold of the goods. If the predicted duration of idling is not greater than the low-temperature tolerance time threshold of the goods, use the minimum allowable temperature of the goods as the allowable pre-cooling lower limit. Otherwise, increase the allowable pre-cooling lower limit according to the ratio of the low-temperature tolerance time threshold of the goods to the predicted duration of idling and the minimum allowable temperature of the goods to the nominal optimal temperature. S42, obtain the current initial temperature of the cargo compartment when the electric-cooled energy storage collaborative mode is started, obtain the maximum temperature reduction range based on the difference between the current initial temperature of the cargo compartment and the allowable pre-cooling lower limit obtained in step S41, and obtain the temporary temperature setting value based on the current initial temperature of the cargo compartment and the maximum temperature reduction range.

[0012] A long-term idling protection control system for fuel cell commercial vehicles includes: The vehicle parameter acquisition module is used to collect the fuel cell output power, vehicle accessory load power, and power battery SOC when the vehicle is idling. The surplus power acquisition module is used to determine whether there is surplus power from the fuel cell based on the fuel cell output power and the load power of the vehicle accessories. The vehicle controller is used to control the power battery to absorb the excess power of the fuel cell when there is excess power in the fuel cell and the SOC of the power battery is less than the set upper limit threshold, and to start the electric-cooled energy storage collaborative mode to improve the operating power of the refrigeration unit when the SOC of the power battery is not less than the set upper limit threshold. Phase change energy storage devices are used to convert surplus electrical energy from fuel cells into cooling energy and store it.

[0013] Preferably, the vehicle controller is also used to reduce the temporary temperature setpoint of the cargo compartment according to the allowable temperature range of the cargo inside the vehicle in the electric-cold energy storage coordinated mode, and to reduce the output power of the fuel cell when the cold storage capacity of the phase change cold storage device reaches the upper limit and the SOC of the power battery is not less than the set upper limit threshold.

[0014] Preferably, the vehicle controller is also used to control the phase change cold storage device to release the stored cold energy when the vehicle exits the idling condition, to assist in the cooling of the cargo box and reduce the operating load of the refrigeration unit.

[0015] Preferably, the fuel cell commercial vehicle long-term idling protection control system further includes an idling judgment module, used to determine that the vehicle is in an idling condition when the vehicle speed is zero and the duration exceeds a preset idling judgment time threshold, and the drive motor power demand is less than a preset power demand threshold.

[0016] Preferably, the vehicle controller includes: The pre-cooling lower limit acquisition unit is used to determine whether there is a risk of low temperature damage to the goods. If so, it acquires the idling prediction duration and the low temperature tolerance duration threshold of the goods, and compares the idling prediction duration and the low temperature tolerance duration threshold of the goods. If the idling prediction duration is not greater than the low temperature tolerance duration threshold of the goods, the minimum allowable temperature of the goods is used as the allowable pre-cooling lower limit. Otherwise, the allowable pre-cooling lower limit is increased according to the ratio of the low temperature tolerance duration threshold of the goods to the idling prediction duration and the minimum allowable temperature of the goods to the nominal optimal temperature. The temporary temperature setting unit is used to obtain the current initial temperature of the cargo compartment when the electric-cooled energy storage collaborative mode is started, obtain the maximum temperature reduction range based on the difference between the current initial temperature of the cargo compartment and the allowable pre-cooling lower limit obtained in step S41, and obtain the temporary temperature setting value based on the current initial temperature of the cargo compartment and the maximum temperature reduction range. Attached Figure Description

[0017] The invention will be further understood from the following description taken in conjunction with the accompanying drawings. The components in the drawings are not necessarily drawn to scale, but rather the emphasis is on illustrating the principles of the embodiments. In different views, the same reference numerals designate corresponding parts.

[0018] Figure 1 This is a schematic diagram of the overall process of a long-term idling protection control method for fuel cell commercial vehicles according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the process of electric-cooled energy storage coordinated idling protection in one embodiment of the present invention; Figure 3 This is a schematic diagram of the system structure and energy flow principle in one embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to its embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the scope of protection of the invention.

[0020] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] In this invention, "first" and "second" do not represent a specific quantity or order, but are merely used to distinguish names.

[0023] Before describing the specific embodiments of the present invention, a brief introduction to the prior art will be given first.

[0024] With the development of new energy vehicle technology, hydrogen fuel cell vehicles are gradually being applied to commercial vehicle fields such as cold chain transportation and logistics distribution due to their advantages of long driving range, short refueling time, and environmental friendliness. At present, fuel cell commercial vehicles typically adopt a hybrid power architecture of "fuel cell system + power battery system", in which the fuel cell system serves as the main energy source, while the power battery system is used for auxiliary power supply, power regulation, and energy recovery.

[0025] During cold chain transportation and logistics distribution, vehicles are often parked or idling for extended periods while loading, unloading, or waiting in line. At these times, the vehicles have virtually no need for driving power, but accessories such as refrigeration units, air conditioners, air compressors, circulating water pumps, and control systems still need to operate continuously. Therefore, the entire vehicle still requires a stable power supply.

[0026] Fuel cell systems cannot maintain efficient and stable operation at arbitrarily low power levels. To maintain operating conditions such as stack temperature, air supply, hydrogen circulation, and cooling circulation, fuel cells typically need to maintain a certain stable output power. Under prolonged idling conditions, this stable output power may exceed the actual electrical demand of vehicle accessories, thus generating excess electrical energy.

[0027] Existing technologies typically address this by reducing the fuel cell's output power, starting and stopping the fuel cell, or utilizing the power battery to absorb excess electrical energy. However, prolonged low-load operation of the fuel cell can lead to decreased operating efficiency, lower stack temperature, and reduced hydrogen utilization; frequent start-stop cycles increase system losses and shorten the fuel cell's lifespan. Therefore, to maintain the fuel cell within a relatively efficient and stable operating range, the power battery is usually used to absorb its excess electrical energy.

[0028] However, this method is mainly suitable for short-term idling conditions. During long-term loading and unloading in refrigerated trucks and logistics vehicles, as the power battery continuously absorbs excess energy, its SOC gradually increases. When it reaches the set upper limit, the power that the power battery can continue to absorb is limited, and the excess energy generated by the fuel cell will be difficult to store further. If an additional energy-consuming load is used to directly consume this energy, it will result in energy waste.

[0029] Therefore, how to maintain the fuel cell in a highly efficient and stable operating range under prolonged idling conditions, while also effectively transferring, storing, and utilizing the excess energy of the fuel cell when the power battery's state of charge (SOC) is high, is a problem that existing technologies need to solve. Based on this, this invention proposes a method and system for long-term idling protection control of fuel cell commercial vehicles based on electric-cooled energy storage synergy.

[0030] This invention aims to solve the above problems and proposes a long-term idling protection control method and corresponding system for fuel cell commercial vehicles based on electric-cooled energy storage synergy. The overall idea is to construct a hierarchical energy management strategy.

[0031] This invention achieves protection for fuel cell commercial vehicles during prolonged idling by coordinating electrical and thermal energy storage. When the vehicle enters a prolonged idling state, such as during loading or unloading, the VCU (Vehicle Controller Unit) collects parameters in real time, including vehicle speed, idling time, fuel cell output power, accessory load, battery SOC, cargo compartment temperature, and phase change thermal storage status, to determine if there is excess fuel cell power. When the fuel cell output power exceeds the vehicle load requirement, the system prioritizes using the battery to absorb excess electrical energy, keeping the fuel cell in a highly efficient and stable operating range. When the battery SOC reaches a set threshold and can no longer store excess electrical energy, the system activates the electrical-thermal energy storage coordinating mode. By increasing the chiller's operating power, the excess electrical energy is converted into cooling energy and stored using the phase change thermal storage device. Simultaneously, the temporary temperature setting is appropriately lowered according to the allowable temperature range of the cargo, achieving pre-cooling of the cargo compartment. When the phase change thermal storage capacity reaches its upper limit, the system further reduces the fuel cell output power or enters a low-power hold-up state to prevent long-term inefficient operation of the fuel cell. After the vehicle restarts, the cold energy in the phase change cold storage device is released, reducing the operating load of the refrigeration unit and allowing more of the fuel cell's output energy to be used for vehicle propulsion.

[0032] like Figure 1 As shown, a method for long-term idling protection control of a fuel cell commercial vehicle includes the following steps: S1 determines whether the vehicle is idling. If so, it collects the fuel cell output power, the vehicle accessory load power, and the power battery SOC.

[0033] Determining whether a vehicle is idling involves the following steps: if the vehicle speed is zero and the duration exceeds a preset idling time threshold, and the drive motor power demand is less than a preset power demand threshold, then the vehicle is determined to be idling.

[0034] Specifically, the conditions for determining idling are that the vehicle speed is zero and the duration exceeds a preset idling time threshold, while the drive motor power demand is zero or close to zero. After the vehicle enters a long-term idling state such as loading and unloading, the VCU collects vehicle operating parameters and status parameters in real time, including fuel cell system output power, vehicle accessory load power, and power battery SOC.

[0035] S2 determines whether there is excess power in the fuel cell based on the fuel cell output power and the load power of the vehicle accessories.

[0036] The VCU compares the collected output power of the fuel cell system with the power demand of the vehicle's accessory loads to determine whether there is any surplus power in the fuel cell.

[0037]

[0038] in, This represents the current output power of the fuel cell. The appendix shows the actual power consumption of the vehicle's accessories.

[0039] when When the value is greater than 0, it indicates that the output power of the fuel cell is higher than the load demand of the vehicle, and there is excess electrical energy.

[0040] S3: If there is excess power in the fuel cell and the SOC of the power battery is less than the set upper limit threshold, the excess power of the fuel cell is absorbed by the power battery.

[0041] When the VCU determines that there is excess power in the fuel cell and the BMS (Battery Management System) detects that the current SOC is less than the set upper limit threshold (e.g., 0.9), the VCU prioritizes controlling the power battery system to absorb the excess power, so that the fuel cell remains in a high-efficiency and stable operating range.

[0042] S4: When the SOC of the power battery is not less than the set upper limit threshold, the electric-cold energy storage collaborative mode is activated to increase the operating power of the chiller and convert the surplus electrical energy of the fuel cell into cold energy, which is then stored through the phase change cold storage device.

[0043] In some cases, fuel cell commercial vehicles employ a fuel cell + small power battery system structure. Under prolonged idling conditions, the power battery's State of Charge (SOC) will quickly reach the preset threshold of 0.9. At this point, the power battery's ability to continue absorbing excess electrical energy is limited, and the VCU (Vehicle Control Unit) activates the electric-cold energy storage collaborative mode. This involves sending a power boost command to the refrigeration unit controller to increase the refrigeration unit's operating power, converting excess electrical energy into cooling capacity. The cooling capacity generated by the refrigeration unit is stored through a phase change energy storage device. This device is filled with phase change materials (such as a combination of organic phase change materials and expanded graphite), utilizing the latent heat of the phase change materials to store the cooling capacity.

[0044] In the electric-cooling energy storage collaborative mode, the VCU appropriately lowers the temporary temperature setpoint of the cargo compartment based on the permissible temperature range of the cargo. For example, the VCU obtains the permissible temperature range of the cargo in the current cargo compartment (e.g., -18℃ to -15℃); within the permissible range, it lowers the temperature setpoint by a preset amount (e.g., lowers it by 1 to 3℃) to achieve pre-cooling of the compartment. This increases the operating load of the refrigeration unit to consume more surplus electrical energy and also reserves cooling capacity for subsequent vehicle operation. When the phase change energy storage device reaches its upper limit (i.e., the energy storage capacity reaches the preset energy storage capacity threshold), and the power battery SOC is still at a high level, the VCU implements fuel cell protection measures, reduces the fuel cell output power, and enters a low-power maintenance state.

[0045] By employing a dual-energy storage strategy combining electricity and cooling, a multi-level energy absorption framework integrating power battery energy storage and phase change cooling energy storage is utilized. When the power battery's state of charge (SOC) is not saturated, it is prioritized for charging; when the SOC is high, it actively switches to cooling energy storage mode, and finally, the fuel cell is protected based on the energy storage status. This tiered energy absorption logic overcomes the limitations of traditional methods that rely solely on electrical energy storage, forming a three-level energy cycle: fuel cell output → power battery charging → phase change cooling energy storage → energy release. This strategy effectively avoids the predicament of having nowhere to dissipate electrical energy after the battery's SOC is saturated, allowing the fuel cell to continue operating within a suitable power range.

[0046] This solution does not simply reduce the load or shut down the fuel cell; instead, it actively increases the chiller power to absorb excess electrical energy. By dynamically adjusting the chiller compressor speed and lowering the cargo compartment temperature setting, the cooling load is temporarily increased, allowing excess electrical energy to be converted into latent heat and stored in the phase change material. In this way, the fuel cell is not forced to reduce its efficiency output, but rather the excess electrical energy is indirectly utilized through an external load.

[0047] Unlike previous cold chain vehicles which were only used to alleviate the cooling load during driving, the phase change cold storage device in this invention becomes a cross-energy domain energy storage medium for fuel cell idling protection.

[0048] As a preferred technical solution, the method for long-term idling protection control of fuel cell commercial vehicles further includes the following steps: S5, when the vehicle exits the idling condition, the phase change cold storage device is controlled to release the stored cold energy to assist in the cooling of the cargo compartment and reduce the operating load of the refrigeration unit.

[0049] Specifically, after the vehicle completes loading and unloading and restarts driving, the VCU executes a cold energy release control strategy. When the VCU detects that the vehicle speed is greater than zero and the drive motor has a power demand, it determines that the vehicle has exited the idling state; the VCU controls the phase change cold storage device to release the stored cold energy to assist in the cooling of the cargo compartment, reduce the operating load of the refrigeration unit, and enable more of the energy output from the fuel cell to be used for vehicle driving, thereby improving the overall energy utilization efficiency of the vehicle.

[0050] In summary, the proposed long-term idling protection control method for fuel cell commercial vehicles prioritizes the use of the power battery to absorb the excess power of the fuel cell when the vehicle is idling. When the SOC of the power battery is not less than the set upper limit threshold, the electric-cold energy storage collaborative mode is activated to increase the operating power of the chiller and convert the excess electrical energy of the fuel cell into cold energy. The cold energy is stored through a phase change cold storage device, thus realizing the joint storage and scheduling of electrical energy and cold energy.

[0051] As a preferred technical solution, the method for obtaining the temporary temperature setpoint includes the following steps: S41. Determine whether there is a risk of low-temperature damage to the goods. If so, obtain the predicted duration of idling and the low-temperature tolerance threshold of the goods. Compare the predicted duration of idling and the low-temperature tolerance threshold of the goods. If the predicted duration of idling is not greater than the low-temperature tolerance threshold of the goods, use the minimum allowable temperature of the goods as the allowable pre-cooling lower limit. Otherwise, increase the allowable pre-cooling lower limit based on the ratio of the low-temperature tolerance threshold of the goods to the predicted duration of idling and the minimum allowable temperature of the goods to the nominal optimal temperature.

[0052] Specifically, for goods at risk of low-temperature damage, such as leafy vegetables and berries, if the cargo compartment temperature exceeds the safe temperature range for a duration longer than the low-temperature tolerance threshold, irreversible damage may occur. This safe temperature range can be represented as [minimum allowable temperature, maximum allowable temperature]. The low-temperature tolerance threshold can be understood as the longest period of time the goods can safely withstand a brief period below the nominal optimal temperature but above the minimum allowable temperature. The nominal optimal temperature can be taken as the midpoint of the safe temperature range. The low-temperature tolerance threshold can be derived from industry standards, cold chain manuals, supplier specifications, or set by technical personnel based on experience.

[0053] The predicted duration of idling can be obtained from the VCU (Vehicle Control Unit), measured in minutes. For example, for different types of operating conditions such as loading, unloading, or queuing, the predicted duration can be determined by statistically averaging the historical idling duration under the corresponding operating conditions. Furthermore, when statistically averaging the historical idling duration under the corresponding operating conditions, the region, station, and seasonal time range can be specified to improve the accuracy of the predicted idling duration.

[0054] If the predicted idling duration is not greater than the cargo's low-temperature tolerance duration threshold, it means that pre-cooling can be sufficient. In this case, the cargo's minimum allowable temperature can be used as the lower limit of allowable pre-cooling. Otherwise, it means that the cargo is not allowed to operate at the cargo's minimum allowable temperature for a long time, and the safety boundary needs to be raised. In this case, the lower limit of allowable pre-cooling can be increased based on the ratio of the cargo's low-temperature tolerance duration threshold to the predicted idling duration, as well as the cargo's minimum allowable temperature and the nominal optimal temperature.

[0055] For example, the permissible pre-cooling lower limit = nominal optimal temperature + safety redundancy coefficient × (cargo's minimum permissible temperature - nominal optimal temperature) × cargo's low-temperature tolerance time threshold / idling prediction duration. The safety redundancy coefficient is generally taken as 0.7-0.9. Thus, the longer the idling prediction duration, the less likely the cargo compartment temperature should be set too low, to avoid prolonged low-temperature damage to the cargo.

[0056] S42, obtain the current initial temperature of the cargo compartment when the electric-cooled energy storage collaborative mode is started, obtain the maximum temperature reduction range based on the difference between the current initial temperature of the cargo compartment and the allowable pre-cooling lower limit obtained in step S41, and obtain the temporary temperature setting value based on the current initial temperature of the cargo compartment and the maximum temperature reduction range.

[0057] At this point, the temporary temperature setpoint is the current initial temperature of the cargo compartment minus the maximum possible temperature reduction. In this way, the excess power of the fuel cell is maximized while ensuring the cargo does not exceed temperature limits, balancing cargo safety and cold storage / charging efficiency.

[0058] After determining the temporary temperature setpoint, the cargo compartment can be pre-cooled using a segmented cooling rate approach, with a faster initial speed followed by a slower rate. The main purpose is to complete the pre-cooling and charging process within the predicted idling time, matching the real-time surplus power of the fuel cell, and avoiding excessively rapid cooling in the early stages, which would leave the fuel cell with nowhere to dissipate the surplus power once the cooling storage is full, forcing the fuel cell to reduce its power output and exit the high-efficiency range prematurely.

[0059] Specifically, the pre-cooling time is obtained based on the predicted idling duration, such as 0.6-0.8 times the predicted idling duration. Next, the average cooling rate is determined based on the ratio of the maximum possible temperature reduction to the pre-cooling time. For the early pre-cooling stage, such as the 0-0.5 times pre-cooling time range, excess power is used for rapid cooling at a rate higher than the average rate; for example, 1.2-1.5 times the average cooling rate can be used as the pre-cooling rate. For the later pre-cooling stage, 0.5-0.8 times the average cooling rate can be used as the pre-cooling rate, gradually slowing down the cooling rate to prevent premature saturation of the cold storage capacity.

[0060] During idling, the actual idling time is updated in real time, the idling duration is corrected, and the actual cargo compartment temperature is collected. The allowable pre-cooling lower limit, the maximum temperature reduction range, and the segmented cooling rate are updated iteratively. Once the cargo compartment temperature reaches the dynamic allowable pre-cooling lower limit, the downward pre-cooling is immediately stopped, and the system switches to the cold storage maintenance mode.

[0061] An embodiment of the present invention also provides a long-term idling protection control system for fuel cell commercial vehicles, including a vehicle parameter acquisition module, a surplus power acquisition module, a vehicle controller, and a phase change cold storage device.

[0062] The vehicle parameter acquisition module is used to acquire the fuel cell output power, vehicle accessory load power, and power battery SOC when the vehicle is idling; the surplus power acquisition module is used to determine whether there is surplus fuel cell power based on the fuel cell output power and vehicle accessory load power.

[0063] The vehicle controller is used to control the power battery to absorb the excess power of the fuel cell when there is excess power in the fuel cell and the SOC of the power battery is less than the set upper limit threshold, and to start the electric-cold energy storage collaborative mode to improve the operating power of the refrigeration unit when the SOC of the power battery is not less than the set upper limit threshold. The phase change cold storage device is used to convert the excess electrical energy of the fuel cell into cold energy and store it.

[0064] The vehicle controller is also used to reduce the temporary temperature setpoint of the cargo compartment in the electric-cold energy storage coordinated mode according to the allowable temperature range of the cargo inside the vehicle, and to reduce the output power of the fuel cell when the cold storage capacity of the phase change cold storage device reaches the upper limit and the SOC of the power battery is not less than the set upper limit threshold; and to control the phase change cold storage device to release the stored cold energy when the vehicle exits the idling condition to assist in the cooling of the cargo compartment and reduce the operating load of the refrigeration unit.

[0065] The aforementioned long-term idling protection control system for fuel cell commercial vehicles also includes an idling judgment module, which is used to determine that the vehicle is in an idling condition when the vehicle speed is zero and the duration exceeds a preset idling judgment time threshold, and the drive motor power demand is less than a preset power demand threshold.

[0066] The core advantage of the system described in this invention lies in its "electricity-cold energy storage synergy" strategy, which systematically resolves the contradiction between excess energy and component protection during prolonged idling in fuel cell commercial vehicles. It prioritizes the absorption of surplus electrical energy by the power battery, and once the battery is fully charged, it drives the chiller to convert electrical energy into cooling energy, which is then stored in a phase change cold storage device. This avoids energy waste and ensures the fuel cell remains in a highly efficient and stable range, significantly reducing the damage to the stack lifespan caused by low-load operation and frequent start-stop cycles. Simultaneously, the stored cooling energy is used for auxiliary cooling after the vehicle restarts, reducing the chiller load during driving and allowing more electrical energy to be used for propulsion, thereby significantly reducing hydrogen consumption and improving overall vehicle economy. Furthermore, the three-tiered management strategy—battery absorption → cold energy storage → protection measures—ensures safety and reliability under all operating conditions, particularly precisely meeting the specific needs of cold chain logistics vehicles requiring long-term parking and continuous chiller operation, achieving cross-time energy transfer and utilization from idling to driving.

[0067] As a preferred technical solution, the vehicle controller includes a pre-cooling lower limit acquisition unit and a temporary temperature setting unit.

[0068] The pre-cooling lower limit acquisition unit is used to determine whether there is a risk of low-temperature damage to the cargo. If so, it acquires the idling prediction duration and the cargo's low-temperature tolerance duration threshold, and compares the idling prediction duration and the cargo's low-temperature tolerance duration threshold. If the idling prediction duration is not greater than the cargo's low-temperature tolerance duration threshold, the cargo's minimum allowable temperature is used as the allowable pre-cooling lower limit. Otherwise, the allowable pre-cooling lower limit is increased based on the ratio of the cargo's low-temperature tolerance duration threshold to the idling prediction duration and the cargo's minimum allowable temperature to the nominal optimal temperature.

[0069] To predict the duration of idling, three types of core historical data can be retrieved when a vehicle enters the geofence of a pre-set loading / unloading yard and triggers the cargo box preparation signal. These data include historical idling duration datasets for the target yard during the same period, weather, and operation type over the past 30 days; standard operation duration data for the current transport order; and idling duration datasets for fuel cell commercial vehicles of the same brand and model. The three types of core historical data are then preprocessed to remove invalid sample data that is abnormally long or too short, and valid samples are retained for calculation.

[0070] Subsequently, the average historical idling time data of the target site over the past 30 days, under the same weather conditions and operation type, is calculated and recorded as the site's historical average idling time T1. The standard operation time data of the work order corresponding to the current transportation order is used as the order work order reservation standard time T2. The average idling time data of fuel cell commercial vehicles of the same brand and model at the site is calculated and recorded as the average idling time of the same vehicle type T3. Finally, the initial baseline idling time T is obtained by weighted fusion of T1, T2, and T3. For example, basic weights can be configured according to the characteristics of commercial vehicle operation scenarios, such as a 50% weight for site operation environment adaptation, a 30% weight for work order standard time constraints, and a 20% weight for vehicle operation characteristics. The initial baseline idling time T is calculated using the weighted fitting formula T = 0.5 × T1 + 0.3 × T2 + 0.2 × T3.

[0071] Preferably, a multi-dimensional scenario correction factor can be introduced to correct the initial baseline idling time T, eliminating interference from the environment and station conditions. The multi-dimensional scenario correction factor includes an environmental correction coefficient K1, a station congestion correction coefficient K2, and a cargo type correction coefficient K3. K1 can be adaptively selected based on ambient temperature, rain, snow, and high / low temperature operating conditions, with the environmental correction coefficient K1 being appropriately amplified in extreme weather. K2 is dynamically calibrated based on the real-time traffic flow and queuing quantity at the station, with the station congestion correction coefficient K2 being appropriately increased in congested conditions. K3 is set differently according to cargo type, with the loading and unloading time coefficient for fresh produce and bulky goods being higher than that for ordinary dry goods. That is, for fresh produce and bulky goods, the cargo type correction coefficient K3 can be appropriately increased.

[0072] The initial baseline idling time T is corrected based on a multi-dimensional scenario correction factor to obtain the final initial predicted total idling time that fits the actual working scenario. This is calculated as: Idle Prediction Duration = T × K1 × K2 × K3. Upper and lower thresholds are then set for this prediction. The upper threshold can be set to the station's historical maximum effective idling time, while the lower threshold is set to the shortest standard working time of the work order, to avoid abnormal prediction values. Here, by introducing a multi-dimensional scenario correction factor, the predicted idling time is fine-tuned based on temperature, rain / snow, and station congestion. In severe weather or station congestion scenarios, the predicted time is automatically and appropriately extended, achieving scenario-appropriate prediction.

[0073] The temporary temperature setting unit is used to obtain the current initial temperature of the cargo compartment when the electric-cooled energy storage collaborative mode is started, obtain the maximum temperature reduction range based on the difference between the current initial temperature of the cargo compartment and the allowable pre-cooling lower limit obtained in step S41, and obtain the temporary temperature setting value based on the current initial temperature of the cargo compartment and the maximum temperature reduction range.

[0074] The temporary temperature setpoint is the current initial temperature of the cargo compartment minus the maximum possible temperature reduction. In this way, the excess power of the fuel cell is maximized while ensuring that the cargo does not exceed the temperature limit, taking into account both cargo safety and cold storage / charging efficiency.

[0075] like Figure 2 The diagram shows the flowchart for the electric-cooled energy storage coordinated idling protection process. First, idling speed is determined and parameters are collected. Excess power is calculated and its value is checked against zero. If it is, energy is recovered through the power battery, and the power battery SOC is checked against 0.9%. Otherwise, the actual load function is applied, and continuous monitoring is performed. If the power battery SOC is greater than 0.9%, the electric-cooled energy storage coordinated mode is activated; otherwise, excess power is absorbed through the power battery, and continuous monitoring continues. After activating the electric-cooled energy storage coordinated mode, the power of the refrigeration unit is increased, phase change cooling is implemented, and the cargo compartment is pre-cooled. It is then determined whether the cooling target has been achieved. If so, the fuel cell output power is reduced for protection. After the vehicle exits idling mode, the cooling capacity of the phase change cooling device is released, and the refrigeration unit load is reduced.

[0076] like Figure 3 The diagram shows the system structure and energy flow principle. The current output from the fuel cell stack is input to the high-voltage DC bus after passing through a converter. A central controller controls the power output of the fuel cell stack and the power battery pack. The current output from the high-voltage DC bus is used to drive the motor and the air conditioning compressor, and the air conditioning compressor (also known as the refrigeration unit) is used for pre-cooling the cargo compartment and for phase change cold storage.

[0077] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for long-term idling protection control of fuel cell commercial vehicles, characterized in that, Includes the following steps: S1 determines whether the vehicle is idling. If so, it collects the fuel cell output power, the vehicle accessory load power, and the power battery SOC. S2, determine whether there is excess power in the fuel cell based on the fuel cell output power and the load power of the vehicle accessories; S3: If there is excess power in the fuel cell and the SOC of the power battery is less than the set upper limit threshold, the excess power of the fuel cell is absorbed by the power battery. S4: When the SOC of the power battery is not less than the set upper limit threshold, the electric-cold energy storage collaborative mode is activated to increase the operating power of the chiller and convert the surplus electrical energy of the fuel cell into cold energy, which is then stored through the phase change cold storage device.

2. The method for long-term idling protection control of a fuel cell commercial vehicle as described in claim 1, characterized in that, Step S4 also includes: in the electric-cold energy storage collaborative mode, reducing the temporary temperature setting value of the cargo compartment according to the allowable temperature range of the cargo inside the vehicle; when the cold storage capacity of the phase change cold storage device reaches the upper limit and the SOC of the power battery is not less than the set upper limit threshold, reducing the output power of the fuel cell and entering a low power hold state.

3. The method for long-term idling protection control of a fuel cell commercial vehicle as described in claim 1, characterized in that, It also includes the following steps: S5 controls the phase change cold storage device to release stored cold energy when the vehicle exits the idling condition, assisting in the cooling of the cargo box and reducing the operating load of the refrigeration unit.

4. The method for long-term idling protection control of a fuel cell commercial vehicle as described in claim 1, characterized in that, In step S1, determining whether the vehicle is in an idling condition specifically includes: if the vehicle speed is zero and the duration exceeds a preset idling determination time threshold, and the drive motor power demand is less than a preset power demand threshold, then the vehicle is determined to be in an idling condition.

5. The method for long-term idling protection control of a fuel cell commercial vehicle as described in claim 2, characterized in that, The method for obtaining the temporary temperature setpoint includes the following steps: S41. Determine whether there is a risk of low-temperature damage to the goods. If so, obtain the predicted duration of idling and the low-temperature tolerance time threshold of the goods. Compare the predicted duration of idling and the low-temperature tolerance time threshold of the goods. If the predicted duration of idling is not greater than the low-temperature tolerance time threshold of the goods, use the minimum allowable temperature of the goods as the allowable pre-cooling lower limit. Otherwise, increase the allowable pre-cooling lower limit according to the ratio of the low-temperature tolerance time threshold of the goods to the predicted duration of idling and the minimum allowable temperature of the goods to the nominal optimal temperature. S42, obtain the current initial temperature of the cargo compartment when the electric-cooled energy storage collaborative mode is started, obtain the maximum temperature reduction range based on the difference between the current initial temperature of the cargo compartment and the allowable pre-cooling lower limit obtained in step S41, and obtain the temporary temperature setting value based on the current initial temperature of the cargo compartment and the maximum temperature reduction range.

6. A long-term idling protection control system for fuel cell commercial vehicles, characterized in that, include: The vehicle parameter acquisition module is used to collect the fuel cell output power, vehicle accessory load power, and power battery SOC when the vehicle is idling. The surplus power acquisition module is used to determine whether there is surplus power from the fuel cell based on the fuel cell output power and the load power of the vehicle accessories. The vehicle controller is used to control the power battery to absorb the excess power of the fuel cell when there is excess power in the fuel cell and the SOC of the power battery is less than the set upper limit threshold, and to start the electric-cooled energy storage collaborative mode to improve the operating power of the refrigeration unit when the SOC of the power battery is not less than the set upper limit threshold. Phase change energy storage devices are used to convert surplus electrical energy from fuel cells into cooling energy and store it.

7. The long-term idling protection control system for fuel cell commercial vehicles as described in claim 6, characterized in that, The vehicle controller is also used to reduce the temporary temperature setpoint of the cargo compartment in the electric-cold energy storage collaborative mode, based on the allowable temperature range of the cargo inside the vehicle, and to reduce the output power of the fuel cell when the cold storage capacity of the phase change cold storage device reaches the upper limit and the SOC of the power battery is not less than the set upper limit threshold.

8. The long-term idling protection control system for fuel cell commercial vehicles as described in claim 6, characterized in that, The vehicle controller is also used to control the phase change cold storage device to release the stored cold energy when the vehicle exits the idling condition, to assist in the cooling of the cargo box and reduce the operating load of the refrigeration unit.

9. A long-term idling protection control system for fuel cell commercial vehicles as described in claim 6, characterized in that, It also includes an idle speed detection module, which determines that the vehicle is in an idle speed condition when the vehicle speed is zero and the duration exceeds a preset idle speed detection time threshold, and the drive motor power demand is less than a preset power demand threshold.

10. A long-term idling protection control system for fuel cell commercial vehicles as described in claim 7, characterized in that, The vehicle controller includes: The pre-cooling lower limit acquisition unit is used to determine whether there is a risk of low temperature damage to the goods. If so, it acquires the idling prediction duration and the low temperature tolerance duration threshold of the goods, and compares the idling prediction duration and the low temperature tolerance duration threshold of the goods. If the idling prediction duration is not greater than the low temperature tolerance duration threshold of the goods, the minimum allowable temperature of the goods is used as the allowable pre-cooling lower limit. Otherwise, the allowable pre-cooling lower limit is increased according to the ratio of the low temperature tolerance duration threshold of the goods to the idling prediction duration and the minimum allowable temperature of the goods to the nominal optimal temperature. The temporary temperature setting unit is used to obtain the current initial temperature of the cargo compartment when the electric-cooled energy storage collaborative mode is started, obtain the maximum temperature reduction range based on the difference between the current initial temperature of the cargo compartment and the allowable pre-cooling lower limit obtained in step S41, and obtain the temporary temperature setting value based on the current initial temperature of the cargo compartment and the maximum temperature reduction range.

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