A crane dpf travel regeneration adaptive control method and crane

Abstract

The application discloses a crane DPF driving regeneration adaptive control method and a crane, and relates to the technical field of engine aftertreatment. The crane comprises an engine, a hoisting system and a DPF. The DPF is arranged in an exhaust pipeline of the engine. The crane DPF driving regeneration adaptive control method comprises the following steps: when a DPF driving regeneration entering condition is met, the engine is controlled to execute an auxiliary braking mode, so that the crane meets the hoisting system idle speed torque demand when waiting for a working condition, or meets the hoisting system output torque demand when hoisting a working condition, and the DPF upstream exhaust temperature T is improved. When the DPF upstream exhaust temperature T reaches T1, the DPF is controlled to enter driving regeneration, wherein T1 is the minimum temperature required for DPF driving regeneration. The crane DPF driving regeneration adaptive control method reduces the parking regeneration frequency, reduces the crane downtime waiting time, and improves the working efficiency of the crane.

Description

Technical Field

[0001] This invention relates to the field of engine aftertreatment technology, and in particular to a crane DPF trolley regeneration adaptive control method and a crane. Background Technology

[0002] Crane operation is characterized by intermittent operation, meaning that a single work cycle includes multiple operations such as waiting, picking up materials, transporting materials, and unloading. Among these, waiting conditions account for approximately 50% of the operation. During waiting conditions, the engine speed is typically below 800 r / min, and the low engine load results in exhaust temperatures below 200℃.

[0003] The engine aftertreatment system treats the exhaust gases from the engine before releasing them into the atmosphere. During crane waiting periods and lifting operations with low loads, carbon soot accumulates in the DPF (Diesel Particulate Filter) and cannot be automatically eliminated. Over time, the accumulated carbon soot in the DPF reaches a certain level, triggering parking regeneration. Parking regeneration requires the crane to completely stop operating, and the engine to increase its speed and load to raise the exhaust temperature. When the exhaust temperature reaches 500℃~600℃ or higher, the accumulated carbon soot in the DPF is oxidized and burned off. However, a complete parking regeneration process typically takes 30 to 40 minutes. During this time, the crane cannot perform any lifting or other operations, severely impacting the crane's operating efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a crane DPF (Device Filter) trolley regeneration adaptive control method and crane, so as to reduce the frequency of parking regeneration, reduce the crane's downtime, and improve the crane's operating efficiency.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] A crane DPF (Device Power Filter) adaptive control method for crane regeneration, wherein the crane includes an engine, a hoisting system, and a DPF, the DPF being installed in the engine's exhaust pipe, and the crane DPF adaptive control method for crane regeneration includes the following steps:

[0007] When the DPF travel regeneration entry condition is met, the engine is controlled to execute the auxiliary braking mode so that the crane meets the idle torque requirement of the hoisting system when waiting for work, or increases the exhaust temperature T upstream of the DPF under the premise of meeting the output torque requirement of the hoisting system when hoisting.

[0008] When the exhaust temperature T upstream of the DPF reaches T1, the DPF is controlled to enter the on-road regeneration process, where T1 is the minimum temperature required for the DPF to undergo on-road regeneration.

[0009] As an optional solution to the aforementioned crane DPF trolley regenerative adaptive control method, the control method for the auxiliary braking mode includes the following steps:

[0010] Calculate the required number of power cylinders and the required number of braking cylinders;

[0011] Based on the calculation results, the engine cylinder state is controlled, and some cylinders are controlled to be in the working state to meet the idle torque requirement or output torque requirement of the hoisting system; some cylinders are controlled to be in the braking state so that the exhaust temperature T upstream of the DPF meets the temperature T1 required for DPF regeneration during driving. The cylinders in the braking state generate negative work to increase the exhaust temperature.

[0012] As an optional scheme of the crane DPF trolley regenerative adaptive control method, the method for calculating the required number of power cylinders and the required number of braking cylinders includes:

[0013] When the cylinder allocation conditions are met, the following steps are performed:

[0014] Based on the idle torque or output torque requirements of the hoisting system, the total torque of the braking load, and the output torque of a single cylinder, calculate the required number of power cylinders.

[0015] The required number of brake cylinders is calculated based on the difference between the upstream exhaust temperature T of the DPF and the minimum temperature T1 required for DPF regeneration during operation.

[0016] As an optional scheme of the crane DPF traveling regeneration adaptive control method, the cylinder allocation condition is: the upstream exhaust temperature of the DPF is T < T1, and the duration is ≥ t1, where t1 = 15 min ~ 25 min;

[0017] If the above conditions are not met, control the engine to exit the auxiliary braking mode.

[0018] As an optional scheme of the crane DPF trolley regeneration adaptive control method, if the sum of the calculated number of working cylinders and the number of braking cylinders is equal to the total number of cylinders, then the calculation result shall be followed.

[0019] If the sum of the calculated number of power cylinders and the number of braking cylinders is greater than the total number of cylinders, the demand for power cylinders will be prioritized, and the number of braking cylinders will be the remaining number of cylinders.

[0020] If the sum of the calculated number of power cylinders and the number of braking cylinders is less than the total number of cylinders, the remaining cylinders after satisfying the requirements for the number of power cylinders and braking cylinders will enter the idling state.

[0021] As an optional embodiment of the crane DPF travel regenerative adaptive control method, the following steps are included after the step of controlling the engine cylinder state based on the calculation results:

[0022] The engine output torque N, the upstream exhaust temperature T of the DPF, and the engine speed fluctuation value ΔV are obtained.

[0023] The decision to adjust the number of brake cylinders and / or the number of power cylinders is based on the engine's output torque N, the exhaust temperature T upstream of the DPF, and the engine speed fluctuation value ΔV.

[0024] As an optional solution to the crane DPF trolley regeneration adaptive control method, the method for determining whether to adjust the number of brake cylinders and / or the number of power cylinders is as follows:

[0025] The engine's output torque N ≥ N1, where N1 is the maximum torque required by the hoisting system at the current speed;

[0026] After controlling the engine cylinder state for a preset duration based on the calculation results, the exhaust temperature upstream of the DPF is T≥T1 and the duration is ≥t1, where t1=15min~25min;

[0027] The engine speed fluctuation value ΔV≤ΔV1, where ΔV1 is the set maximum fluctuation value;

[0028] If any of the above conditions are not met, the number of the power cylinder and / or the braking cylinder needs to be dynamically adjusted.

[0029] As an optional solution to the crane DPF trolley regeneration adaptive control method, the method for adjusting the number of the power cylinder and / or the braking cylinder is as follows:

[0030] If the exhaust temperature T upstream of the DPF is less than T1, then the number of brake cylinders is increased, or the current state is maintained, and an alarm is triggered.

[0031] If the engine's output torque N < N1, or the engine's speed fluctuation value ΔV > ΔV1, then the number of power cylinders is increased.

[0032] As an optional scheme of the aforementioned crane DPF trolley regeneration adaptive control method, the DPF trolley regeneration entry condition is:

[0033] The crane is in the process of being loaded onto the crane.

[0034] The engine speed V≥V1, where V1 is the minimum speed required to satisfy vehicle regeneration.

[0035] The carbon load C of DPF is between the driving regenerated carbon load threshold and the parking regenerated carbon load threshold.

[0036] The engine's output torque N≤N2 and the duration ≥t2, where N2 is the upper limit of the engine output torque that allows the brake cylinder to be opened, and t2=3min~5min;

[0037] When the above conditions are met simultaneously, the engine is controlled to execute the auxiliary braking mode.

[0038] As an optional solution to the crane DPF traveling regenerative adaptive control method, the overhead crane operation is triggered by a remote throttle switch to the overhead crane throttle signal.

[0039] A crane, comprising:

[0040] engine;

[0041] A hoisting system, wherein the engine provides power to the hoisting system;

[0042] A DPF, located in the exhaust pipe of the engine, is used to capture carbon particles in the engine exhaust gas.

[0043] The DPF is configured to perform regeneration using the crane DPF trolley regeneration adaptive control method described in any of the above schemes.

[0044] The beneficial effects of this invention are:

[0045] The crane DPF travel regeneration adaptive control method provided by this invention utilizes the characteristic that the engine can increase exhaust temperature in auxiliary braking mode. When the conditions for DPF travel regeneration are met, the engine is controlled to execute auxiliary braking mode, so that the crane can meet the idling speed requirements of the lifting system during waiting conditions, or meet the output torque requirements of the lifting system during lifting conditions, thereby increasing the upstream exhaust temperature T of the DPF. When the upstream exhaust temperature T of the DPF reaches the minimum temperature T1 required for DPF travel regeneration, the DPF automatically enters travel regeneration. This crane DPF travel regeneration adaptive control method, by dynamically matching the torque requirements of the lifting system, enables real-time removal of DPF carbon soot during both waiting and lifting conditions of the crane during loading operations, reducing the frequency of parking regeneration, reducing crane downtime, and improving crane operating efficiency.

[0046] The crane provided by this invention includes an engine, a lifting system, and a DPF (Device Filter). The engine provides power to the lifting system. The DPF is located in the engine's exhaust pipe and is used to collect carbon particles from the engine exhaust gas. The DPF is configured to regenerate using the aforementioned crane DPF travel regeneration adaptive control method. This allows the crane to autonomously engage in travel regeneration during both waiting and lifting operations, provided that the idle torque or output torque requirements of the lifting system are met. This reduces the frequency of parking regeneration, decreases crane downtime, and improves crane operating efficiency. Attached Figure Description

[0047] Figure 1 This is a flowchart of the crane DPF trolley regeneration adaptive control method provided in an embodiment of the present invention;

[0048] Figure 2 This is a flowchart of the control method for the auxiliary braking mode provided in an embodiment of the present invention. Detailed Implementation

[0049] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0050] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0051] Unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and connections within two components or interactions between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0052] Unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of a second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0053] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0054] Cranes are devices used for vertically lifting and horizontally moving heavy objects. Common types include truck cranes, crawler cranes, and tire cranes.

[0055] The crane includes an engine, a lifting system, and an engine aftertreatment system. The engine is a diesel engine. The hydraulic drive system of the lifting system includes a hydraulic pump, and the engine aftertreatment system includes a DPF (discharge powder filter), which is located in the engine's exhaust pipe. During crane operation, the engine drives the hydraulic pump to generate high-pressure oil, controlling the lifting system's hoisting, luffing, and telescopic boom movements to achieve intermittent work cycles (waiting, picking up materials, transporting materials, and unloading materials).

[0056] To meet emission regulations, all models are equipped with a DPF (Diesel Particulate Filter) to capture carbon particles in the exhaust. As carbon particles accumulate, they increase engine exhaust back pressure, reduce power performance, and increase fuel consumption; therefore, the DPF must be regenerated to remove carbon soot and maintain system efficiency.

[0057] DPF regeneration is a chemical reaction in which carbon particles in the DPF react with O2, NO, and NO2 in the engine exhaust gas at different temperatures, eliminating the carbon particles in the DPF. DPF regeneration includes passive regeneration and active regeneration. Active DPF regeneration is further divided into on-the-go regeneration and parking regeneration. On-the-go regeneration requires no human intervention and is automatically triggered during operation without interruption. Parking regeneration requires the machine to be stopped and manually started, forcibly raising the exhaust temperature to above 500℃~600℃. Since waiting conditions account for up to 50% of crane operations, the engine speed is usually below 800r / min during waiting conditions, resulting in low engine load and exhaust temperature below 200℃. Under these conditions, the DPF is in a state of pure carbon soot accumulation and has no self-cleaning ability. When the carbon soot in the DPF accumulates to the parking regeneration threshold, the system forcibly triggers parking regeneration. One parking regeneration takes 30 to 40 minutes to complete. During this period, the entire vehicle cannot perform any lifting or other operations, severely affecting the crane's operating efficiency.

[0058] To address the high prevalence of low-speed, low-load operating conditions and frequent parking regeneration in cranes, this embodiment provides a crane DPF (Device Power Filter) adaptive control method for crane travel regeneration. This method eliminates the need for additional pressure sensors or electronic control systems. By monitoring the lifting system's actions in real-time through the engine ECU, it obtains the lifting system's demands on engine speed and torque. During crane loading operations, even low-speed, low-load conditions can meet the requirements for travel regeneration, reducing the frequency of parking regeneration. This significantly reduces crane downtime and improves operational efficiency.

[0059] When engine auxiliary braking is activated, fuel injection to the cylinders stops. As the piston approaches top dead center during the compression stroke, the exhaust valve opens, releasing the work done by the engine during the compression of air into the exhaust system. During the expansion stroke, the exhaust valve closes, and the piston's downward movement is similar to a vacuum process, generating negative work, increasing engine load, and consequently increasing exhaust temperature. Furthermore, during engine auxiliary braking, fuel is cut off to the cylinders used for auxiliary braking, and the regeneration process essentially does not increase fuel consumption; compared to the forced injection and warm-up during parking regeneration, fuel consumption is reduced.

[0060] like Figure 1 As shown, this embodiment provides a crane DPF trolley regeneration adaptive control method, including the following steps:

[0061] S10. When the conditions for DPF travel regeneration are met, control the engine to execute the auxiliary braking mode so that the crane meets the idle torque requirements of the hoisting system when waiting for work, or increases the exhaust temperature T upstream of the DPF while meeting the output torque requirements of the hoisting system during hoisting work.

[0062] During crane loading operations, when the conditions for DPF crane regeneration are met, crane regeneration is automatically triggered, eliminating the need for parking regeneration and reducing crane downtime.

[0063] In one embodiment, the DPF travel regeneration entry condition must simultaneously meet the following conditions:

[0064] (1) The crane is in the process of loading.

[0065] When the crane is in the loading operation, the lifting system will be in a waiting state before picking up materials or after unloading materials. In the waiting state or in the lifting state with a small load on the lifting system, the engine speed is low and the load is low. The carbon soot in the DPF is in the pure accumulation stage, which may accumulate to the parking regeneration threshold and trigger parking regeneration. In order to reduce the frequency of parking regeneration, reduce downtime and improve work efficiency, it is necessary to enter DPF traveling regeneration before entering parking regeneration in order to remove the carbon soot in the DPF.

[0066] Specifically, the identification method for on-vehicle operation is as follows: on-vehicle operation is triggered by remote throttle switching to the on-vehicle throttle signal.

[0067] When the engine ECU receives the switching signal of the remote throttle switch via the CAN bus and recognizes the signal that the crane's overhead throttle is open, it determines that the crane has entered the overhead operation phase.

[0068] (2) The engine speed V≥V1, where V1 is the minimum speed required to satisfy vehicle regeneration.

[0069] The engine ECU obtains the engine speed. When the engine speed V is greater than or equal to the minimum speed V1 required for vehicle-borne regeneration, it ensures that the DPF maintains the minimum exhaust flow and temperature required for DPF regeneration. Furthermore, when the engine speed V is greater than or equal to V1 and remains so for a certain period of time, it ensures that the exhaust temperature is stably transferred to the DPF, thereby ensuring a stable temperature field for DPF regeneration.

[0070] (3) The carbon load C of the DPF is between the driving regenerated carbon load threshold and the parking regenerated carbon load threshold.

[0071] The carbon load of a DPF refers to the amount of carbon particulate matter accumulated inside the DPF, serving as an important indicator for measuring the DPF's operating status and regeneration requirements. During crane loading operations, the carbon load of the DPF needs to be monitored in real time and transmitted to the engine ECU. Specifically, this is done by measuring the exhaust pressure difference before and after the DPF, combined with exhaust flow and temperature parameters, to calculate the real-time carbon load.

[0072] The carbon load C of the DPF is greater than the driving regeneration carbon load threshold and less than the parking regeneration carbon load threshold to ensure the feasibility of driving regeneration and avoid triggering parking regeneration of the DPF.

[0073] (4) The engine output torque N≤N2 and the duration ≥t2, where N2 is the upper limit of the engine output torque that allows the brake cylinder to be opened, and t2=3min~5min.

[0074] When the engine is in auxiliary braking mode, a portion of its effective output power is used to drive the braking system (such as exhaust butterfly valves, bleed brakes, or compression release brakes) instead of outputting driving power. This reduces the effective output power of the engine available to drive the lifting system. Forcing a start during periods of high torque demand may cause instability in the lifting operation, leading to speed fluctuations. Before controlling the engine to execute auxiliary braking mode, it must be confirmed that the current engine output torque, while meeting the output torque of the lifting system, can open at least one brake cylinder to increase the exhaust temperature T upstream of the DPF, with a duration ≥ t2, filtering out short-term torque fluctuations. DPF regeneration should only be initiated when the engine is stably under low load, ensuring that the exhaust temperature T upstream of the DPF is increased upon entering DPF regeneration. Furthermore, instantaneous low torque cannot establish a stable temperature field, and frequent starts and stops of DPF regeneration will lead to incomplete oxidation of DPF carbon deposits. Therefore, it is necessary to ensure that the internal temperature of the DPF is uniformly conducted to a level above the minimum temperature T1 required for DPF regeneration.

[0075] The method for obtaining N2 is either a lookup table method or a real-time calculation method. The specific method using the lookup table method is as follows: Query the pre-calibrated pulse spectrum. Input parameters include engine speed, required lifting torque, and accessory load. The output value is N2. This pulse spectrum is calibrated using the formula: N2 = Required torque of the lifting system × Safety factor - Single brake cylinder load torque. The safety factor, greater than 1, is determined through calibration and is used to cover uncertainties such as dynamic response and friction changes, ensuring reliable lifting operations. The single brake cylinder load torque is measured at different engine speeds through brake bench tests to obtain a brake consumption model, which is pre-stored in the engine ECU. The single brake cylinder load torque is obtained based on the current speed and operating parameters, using the pre-stored brake consumption model.

[0076] The specific method of using the real-time calculation method is as follows: According to the formula N2 = hoisting system required torque × safety factor - single brake cylinder load torque, the hoisting system required torque is calculated in real time, and the single brake cylinder load torque is obtained in real time. Then, it is substituted into the above formula to obtain the result.

[0077] For example, N2 = 100N, t2 = 3min ~ 5min.

[0078] The control logic for the above entry conditions is as follows: when the engine output torque N≤N2 and the duration is ≥t2, the brake cylinder is allowed to be opened; otherwise, the brake cylinder is prohibited from being opened.

[0079] S20. When the exhaust temperature T upstream of the DPF reaches T1, control the DPF to enter the on-road regeneration; where T1 is the minimum temperature required for the DPF to enter the on-road regeneration.

[0080] When the engine enters auxiliary braking mode, the cylinders in braking mode stop injecting fuel. As the piston approaches top dead center during the compression stroke, the exhaust valve opens, releasing the work done by the engine during the compression of air into the exhaust system. During the expansion stroke, the exhaust valve closes, and the piston moves downwards, similar to a vacuum process, generating negative work, increasing the engine load, and consequently increasing the exhaust temperature. When the exhaust temperature T upstream of the DPF reaches the minimum temperature T1 required for DPF regeneration during operation, the DPF automatically enters regeneration mode.

[0081] A temperature sensor is located upstream of the DPF. The temperature detected by the temperature sensor is sent to the engine ECU in real time. The engine ECU controls the DPF to enter the driving regeneration mode based on the real-time exhaust temperature upstream of the DPF.

[0082] In one embodiment, such as Figure 2 As shown, the control method for the auxiliary braking mode includes the following steps:

[0083] S11. Calculate the required number of power cylinders and the required number of braking cylinders.

[0084] S12. Based on the calculation results, control the engine cylinder state, controlling some cylinders to be in a working state to meet the idle torque or output torque requirements of the hoisting system. Control some cylinders to be in a braking state to ensure that the exhaust temperature T upstream of the DPF meets the temperature T1 required for DPF regeneration during operation. Specifically, the cylinders in the braking state generate negative work to increase the exhaust temperature.

[0085] The engine includes multiple cylinders; for example, the engine includes six or eight cylinders. When the engine is in auxiliary braking mode, a portion of the cylinders are in a power state, providing power to the lifting system to meet its lifting requirements. While meeting the lifting system's idle torque or output torque requirements, another portion of the cylinders are in a braking state to increase the exhaust temperature upstream of the DPF, reaching the temperature required for DPF regeneration during operation. This allows carbon particles in the DPF to chemically react with the exhaust gas from the engine, eliminating carbon particles and reducing the frequency of triggering parking regeneration.

[0086] Specifically, the method for calculating the required number of power cylinders and the required number of braking cylinders includes the following steps when the cylinder allocation conditions are met: calculate the required number of power cylinders based on the idle torque requirement or output torque requirement of the hoisting system, the total torque of the braking load and the output torque of a single cylinder; calculate the required number of braking cylinders based on the difference between the upstream exhaust temperature T of the DPF and the minimum temperature T1 required for DPF regeneration during travel.

[0087] When the engine is in auxiliary braking mode, the number of power cylinders and braking cylinders required are first calculated. Then, the engine cylinder state is controlled according to the calculation results. Under the premise of meeting the idle torque requirements or output torque requirements of the hoisting system, the driving regeneration is ensured before the DPF enters parking regeneration to remove carbon particles from the DPF.

[0088] Specifically, when the lifting system is unloaded and in a waiting state, the engine needs to maintain a stable idling speed. The required idling torque is the sum of the base idling torque and the accessory load torque. The base idling torque is the minimum torque required to maintain engine idling (no accessories, no braking), used to overcome internal friction and pumping losses. The base idling torque is obtained by calibrating a base idling torque and coolant temperature mapping table through bench testing and pre-storing it in the engine ECU. A coolant temperature sensor collects the coolant temperature in real time and sends it to the engine ECU. The engine ECU uses the acquired coolant temperature to look up the current base idling torque in the table. The accessory load torque is the torque consumption for driving accessories such as the air conditioning compressor, generator, and hydraulic pump. It can be measured in real time by installing a torque sensor on the accessory drive shaft.

[0089] The output torque of the lifting system is determined by the hydraulic pump load. The hydraulic pump load is calculated based on the hydraulic pump operating pressure, hydraulic pump displacement, and the mechanical efficiency from the engine to the hydraulic pump. The hydraulic pump operating pressure is collected in real time by a pressure sensor and sent to the engine ECU. The hydraulic pump displacement is obtained by looking up a table based on the pump control handle opening. The mechanical efficiency from the engine to the hydraulic pump is pre-stored in the engine ECU. For example, the mechanical efficiency from the engine to the hydraulic pump is 0.85 to 0.92. Then, the engine ECU calculates the output torque requirement of the lifting system based on the acquired parameters and the pre-stored calculation formula for the hydraulic pump load. The calculation formula for the hydraulic pump load is existing technology and will not be elaborated here.

[0090] The method for determining the total braking load torque is as follows: determine the load torque of a single brake cylinder based on the braking consumption model pre-stored in the engine ECU and the current speed; multiply the load torque of a single brake cylinder by the number of brake cylinders currently activated to obtain the total braking load torque.

[0091] The calculation method for the number of power cylinders is as follows: The torque output capacity of a single cylinder is calibrated. The calibration method involves obtaining a mapping table between the output torque of a single cylinder and its speed through experimental data. This mapping table is then pre-stored in the engine ECU. The engine ECU looks up the output torque of a single cylinder based on the real-time speed. Finally, based on the calculated output torque requirement of the hoisting system, the total braking load torque, and the output torque of a single cylinder, the theoretical number of power cylinders is obtained. For example, taking the hoisting system under hoisting conditions: Theoretical number of power cylinders = (output torque requirement of the hoisting system + total braking load torque) / output torque of a single cylinder. Then, the calculated theoretical number of power cylinders is rounded and processed. If the final theoretical number of power cylinders is greater than the total number of cylinders, then the final number of power cylinders is the total number of cylinders. The final number of power cylinders is the smallest integer not less than the theoretical number of power cylinders and not exceeding the total number of cylinders.

[0092] The method for calculating the number of brake cylinders is as follows: Based on the experiment, a mapping table is established between the difference between the upstream exhaust temperature of the DPF and the minimum temperature required for DPF regeneration during operation and the number of brake cylinders. Then, the corresponding number of brake cylinders is obtained by looking up the table based on the calculated temperature difference.

[0093] Furthermore, the cylinder allocation condition is: the real-time exhaust temperature upstream of the DPF, T < T1, and the duration is ≥ t1, where t1 = 15 min ~ 25 min. When the above conditions are not met, the engine is controlled to exit the auxiliary braking mode. When allocating cylinders, it is necessary to determine that the exhaust temperature T upstream of the DPF is in a continuously low temperature state, at which point active intervention to raise the temperature is required.

[0094] For example, T1 = 200℃~250℃, t1 = 20min.

[0095] If the sum of the calculated number of power cylinders and the number of braking cylinders equals the total number of cylinders, then the calculation result will be followed to maximize regeneration efficiency.

[0096] If the sum of the calculated number of power cylinders and the number of braking cylinders is greater than the total number of cylinders, the demand for power cylinders will be prioritized, and the number of braking cylinders will be the remaining number of cylinders. Priority will be given to ensuring operational safety, sacrificing some temperature rise capability, and waiting for the exhaust temperature T upstream of the DPF to rise to T1.

[0097] If the sum of the calculated number of power cylinders and the number of braking cylinders is less than the total number of cylinders, the remaining cylinders after satisfying the number of power cylinders and braking cylinders will enter the idling state. The cylinders in the idling state will not inject oil or brake, so that the power adjustment margin can be reserved to cope with sudden loads, or the temperature adjustment margin can be reserved to cope with the fact that the exhaust temperature upstream of the DPF cannot reach T1, while avoiding excessive heating and damage to the DPF.

[0098] Since the number of power cylinders directly determines the power output capacity, insufficient power cylinders will cause the load to fall and the hydraulic system to lose pressure, affecting the safety of crane operation. Therefore, in the process of adaptive control of crane DPF trolley regeneration, a dual-objective optimization of safety and efficiency is established through the principle of prioritizing power cylinders and the remaining cylinder allocation mechanism.

[0099] S13. Obtain the engine's output torque N, the exhaust temperature T upstream of the DPF, and the engine speed fluctuation value ΔV.

[0100] S14. Based on the engine's output torque N, the exhaust temperature T upstream of the DPF, and the engine speed fluctuation value ΔV, determine whether to adjust the number of brake cylinders and / or the number of power cylinders. If yes, proceed to S15; otherwise, proceed to S20.

[0101] In one embodiment, the method for determining whether to adjust the number of brake cylinders and / or the number of power cylinders is as follows:

[0102] The engine's output torque N ≥ N1, where N1 is the maximum torque required by the hydraulic pump at the current speed.

[0103] After controlling the engine cylinder state for a preset time based on the calculation results, the exhaust temperature upstream of the DPF is T≥T1, and the duration is ≥t1, where t1=15min~25min.

[0104] The engine speed fluctuation value ΔV ≤ ΔV1, where ΔV1 is the set maximum fluctuation value.

[0105] If any of the above conditions are not met, the number of power cylinders and / or braking cylinders needs to be dynamically adjusted.

[0106] S15. The method for adjusting the number of power cylinders and / or brake cylinders is as follows:

[0107] If the exhaust temperature T upstream of the DPF is less than T1, the number of brake cylinders will be increased, or the current state will be maintained, and an alarm will be triggered.

[0108] Based on the exhaust temperature T upstream of the DPF obtained by the engine ECU, it is determined whether the exhaust temperature T upstream of the DPF reaches the minimum temperature T1 required for DPF regeneration during operation. If it does not reach the minimum temperature T1 required for DPF regeneration during operation, it indicates that the number of brake cylinders is insufficient. If there are idle cylinders, the number of brake cylinders can be increased to ensure that the exhaust temperature upstream of the DPF reaches T1, so that the DPF can enter regeneration during operation. If there are no idle cylinders, the current state is maintained and an alarm is triggered to remind the operator that the exhaust temperature T upstream of the DPF under the current operating condition cannot reach the minimum temperature T1 required for DPF regeneration during operation. When the carbon load of the DPF reaches the carbon load threshold for parking regeneration, the crane will enter parking regeneration.

[0109] If the engine's output torque N < N1, or the engine's speed fluctuation value ΔV > ΔV1, then increase the number of power cylinders.

[0110] The engine ECU obtains the engine's output torque N and engine speed fluctuation value ΔV. If the engine's output torque N < N1, it means that the engine's output torque does not meet the torque required by the lifting system. In this case, the number of power cylinders needs to be increased to prioritize meeting the torque requirements of the lifting system. If there are idle cylinders, they can be added as power cylinders. If there are no idle cylinders, the number of power cylinders can be increased by reducing the number of braking cylinders.

[0111] If the engine's output torque N ≥ N1, it means that the engine's output torque N meets the torque requirements of the lifting system. When the engine's output torque N ≥ N1, if the torque margin is large, the engine speed fluctuation is small; if the torque margin is small, the engine speed fluctuation is large. If the engine speed fluctuation value ΔV > ΔV1, it means that the lifting system is unstable and prone to major safety hazards. If there is an idling cylinder, it can be added as a power cylinder; if there is no idling cylinder, the number of power cylinders can be increased by reducing the number of braking cylinders.

[0112] For example, ΔV1 = 80 r / min ~ 120 r / min.

[0113] After adjusting the number of power cylinders and / or brake cylinders, return to S14 until it is no longer necessary to adjust the number of brake cylinders and / or power cylinders. When the exhaust temperature T upstream of the DPF reaches T1, control the DPF to automatically enter the driving regeneration.

[0114] The crane DPF travel regeneration adaptive control method provided in this embodiment utilizes the characteristic that the engine can increase exhaust temperature in auxiliary braking mode. When the conditions for DPF travel regeneration are met, the engine is controlled to execute auxiliary braking mode, so that the crane meets the idle torque requirements of the lifting system during waiting conditions and the output torque requirements of the lifting system during lifting conditions, while increasing the exhaust temperature upstream of the DPF. When the exhaust temperature T upstream of the DPF reaches the minimum temperature T1 required for DPF travel regeneration, the DPF automatically enters travel regeneration. This crane DPF travel regeneration adaptive control method, by dynamically matching the torque requirements of the lifting system, enables real-time removal of DPF carbon soot during both waiting and lifting conditions of the crane, reducing the frequency of parking regeneration, reducing crane downtime, and improving crane operating efficiency.

[0115] This embodiment also provides a crane, including an engine, a lifting system, and a DPF (Device Filter). The engine provides power to the lifting system. The DPF is located in the engine's exhaust pipe and is used to collect carbon particles from the engine exhaust gas. The DPF is configured to regenerate using the aforementioned crane DPF travel regeneration adaptive control method. This allows the crane to autonomously engage in travel regeneration during both waiting and lifting operations, while meeting the idling and output torque requirements of the lifting system. This reduces the frequency of parking regeneration, decreases crane downtime, and improves crane operating efficiency.

[0116] The above description is only a preferred embodiment of the present invention. For those skilled in the art, there will be changes in the specific implementation and application scope based on the ideas of the present invention. The content of this specification should not be construed as a limitation of the present invention.

Claims

1. A crane DPF (Device Power Filter) adaptive control method for crane regeneration, wherein the crane includes an engine, a hoisting system, and a DPF, the DPF being installed in the exhaust pipe of the engine, characterized in that, The crane DPF trolley regenerative adaptive control method includes the following steps: When the DPF travel regeneration entry condition is met, the engine is controlled to execute the auxiliary braking mode so that the crane meets the idle torque requirement of the hoisting system when waiting for work, or increases the exhaust temperature T upstream of the DPF under the premise of meeting the output torque requirement of the hoisting system when hoisting. When the exhaust temperature T upstream of the DPF reaches T1, the DPF is controlled to enter the driving regeneration process, where T1 is the minimum temperature required for the DPF to regenerate during driving. The control method for the auxiliary braking mode includes the following steps: Calculate the required number of power cylinders and the required number of braking cylinders; Based on the calculation results, the engine cylinder state is controlled, and some cylinders are controlled to be in the working state to meet the idle torque requirement or output torque requirement of the hoisting system; some cylinders are controlled to be in the braking state so that the exhaust temperature T upstream of the DPF meets the temperature T1 required for DPF regeneration during driving. In the braking state, the cylinders do work by compressing the air in the cylinder through the piston during the compression stroke, and generate negative work by drawing a vacuum through the piston during the expansion stroke to increase the exhaust temperature. Methods for calculating the required number of power cylinders and brake cylinders include: When the cylinder allocation conditions are met, the following steps are performed: Based on the idle torque or output torque requirements of the hoisting system, the total braking load torque, and the single-cylinder output torque, the required number of power cylinders is calculated. Specifically, the single-braking cylinder load torque is determined according to the braking consumption model pre-stored in the engine ECU and the current speed. The single-braking cylinder load torque is multiplied by the number of currently activated braking cylinders to obtain the total braking load torque. A mapping table between single-cylinder output torque and speed is obtained, and the single-cylinder output torque is obtained by looking up the table based on the real-time speed. Based on the mapping table between the difference between the upstream exhaust temperature T of the DPF and the minimum temperature T1 required for DPF regeneration during driving and the number of brake cylinders, the corresponding number of brake cylinders can be obtained by looking up the table according to the calculated temperature difference. The cylinder distribution condition is as follows: the exhaust temperature upstream of the DPF is T < T1, and the duration is ≥ t1, where t1 = 15 min ~ 25 min; If the above conditions are not met, control the engine to exit the auxiliary braking mode; The conditions for entering the DPF vehicle regeneration are as follows: The crane is in the process of being loaded onto the crane. The engine speed V≥V1, where V1 is the minimum speed required to satisfy vehicle regeneration. The carbon load C of DPF is between the driving regenerated carbon load threshold and the parking regenerated carbon load threshold. The engine's output torque N≤N2 and the duration ≥t2, where N2 is the upper limit of the engine output torque that allows the brake cylinder to be opened, and t2=3min~5min; When the above conditions are met simultaneously, the engine is controlled to execute the auxiliary braking mode.

2. The crane DPF trolley regeneration adaptive control method according to claim 1, characterized in that, If the sum of the calculated number of power cylinders and the number of braking cylinders equals the total number of cylinders, then the calculation result shall be followed. If the sum of the calculated number of power cylinders and the number of braking cylinders is greater than the total number of cylinders, the demand for power cylinders will be prioritized, and the number of braking cylinders will be the remaining number of cylinders. If the sum of the calculated number of power cylinders and the number of braking cylinders is less than the total number of cylinders, the remaining cylinders after satisfying the requirements for the number of power cylinders and braking cylinders will enter the idling state.

3. The crane DPF trolley regeneration adaptive control method according to claim 1, characterized in that, Following the step of controlling the engine cylinder state based on the calculation results, the following steps are also included: The engine output torque N, the exhaust temperature T upstream of the DPF, and the engine speed fluctuation value ∆V are obtained. The decision to adjust the number of brake cylinders and / or the number of power cylinders is based on the engine's output torque N, the exhaust temperature T upstream of the DPF, and the engine speed fluctuation value ∆V.

4. The crane DPF trolley regeneration adaptive control method according to claim 3, characterized in that, The method for determining whether to adjust the number of brake cylinders and / or the number of power cylinders is as follows: The output torque of the engine is N≥N1, where N1 is the maximum required torque of the hoisting system at the current speed; After controlling the engine cylinder state for a preset duration based on the calculation results, the exhaust temperature upstream of the DPF is T≥T1 and the duration is ≥t1, where t1=15min~25min; The engine speed fluctuation value ∆V≤∆V1, where ∆V1 is the set maximum fluctuation value; If any of the above conditions are not met, the number of the power cylinder and / or the braking cylinder needs to be dynamically adjusted.

5. The crane DPF trolley regeneration adaptive control method according to claim 4, characterized in that, The method for adjusting the number of the power cylinder and / or the braking cylinder is as follows: If the exhaust temperature T upstream of the DPF is less than T1, then the number of brake cylinders is increased, or the current state is maintained, and an alarm is triggered. If the engine's output torque N < N1, or the engine's speed fluctuation value ∆V > ∆V1, then the number of power cylinders is increased.

6. The crane DPF trolley regeneration adaptive control method according to claim 1, characterized in that, The loading operation is triggered by a remote throttle switch to the loading throttle signal.

7. A crane, characterized in that, include: engine; A hoisting system, wherein the engine provides power to the hoisting system; DPF, located in the exhaust pipe of the engine, is used to capture carbon particles in the engine exhaust gas; The DPF is configured to perform regeneration using the crane DPF trolley regeneration adaptive control method as described in any one of claims 1-6.

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