Agricultural machine and method, apparatus and medium for power control thereof

Abstract

The application relates to the technical field of agricultural machinery, and discloses a power control method for agricultural machinery, which comprises the following steps: estimating initial demand power generation of the agricultural machinery according to a current whole-machine operation condition of the agricultural machinery; obtaining a compensation correction value associated with power generation efficiency based on a power difference between power generation request power of the agricultural machinery at a previous moment and actual power generation power of the agricultural machinery at a current moment; and correcting the initial demand power generation based on the compensation correction value and a correction coefficient associated with atmospheric pressure to obtain final demand power generation. The application fully considers the influence of power generation efficiency and atmospheric pressure on power generation power following accuracy, and proposes a corresponding compensation correction scheme, so that the actual power generation power infinitely approaches the target power generation power, and the driving and operation requirements of the agricultural machinery are met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of agricultural machinery, in particular to an agricultural machinery and a power control method, device and medium thereof. BACKGROUND

[0002] On the one hand, traditional fuel agricultural machinery, taking a traditional fuel harvester as an example, has a structure as shown in FIG. 1(a), has many working components, and is directly powered by an engine, part of the power is transmitted to the traveling and working mechanism through multi-stage belts and hydraulic devices, and has the defects of excessive load of the transmission system (part of which reaches 6-stage transmission), high failure rate, large vibration and noise, etc. Moreover, in the working process, the multiple functional modules of the traditional fuel harvester are fixed in speed ratio, which requires the engine speed to be fixed at a specific stage, so that the engine utilization rate is limited, quantization is difficult, and the energy efficiency optimization and improvement space is limited. In addition, the variable working environment, road conditions and other working conditions will cause the engine load of the traditional fuel harvester to fluctuate disorderly, and the engine fuel utilization rate under non-stable operating conditions is low. These objective reasons lead to the bottleneck of work efficiency improvement and energy optimization of traditional fuel agricultural machinery in the working process.

[0003] On the other hand, in current social life, environmental and energy problems are increasingly severe, and energy saving, emission reduction, low carbon, etc. have become the technical development of future industrial vehicles and agricultural vehicles. The current popular new energy technology, due to its high efficiency, cleanliness, environmental protection and other characteristics, is bound to be the only way for future sustainable development. However, in agricultural machinery vehicles, due to the influence of working environment and infrastructure conditions, pure electric technology is limited in terms of endurance, energy supply and other scenes, and cannot completely replace traditional fuel vehicles in a short time. Under this circumstance, hybrid power assembly has the advantages of high efficiency, low emission, convenient energy supply and convenient endurance, and becomes the most effective transitional mode in current agricultural implements.

[0004] However, in the hybrid power control system of agricultural machinery, the conventional power following control method can make the engine run in the entire load region, and basically run along the set optimal fuel consumption curve, but in consideration of the delay characteristics of the hybrid generator power generation, the plateau climate and other conditions, the current curve cannot meet the driving and running requirements. SUMMARY

[0005] The purpose of the embodiments of the present application is to provide an agricultural machinery and a power control method, device and medium thereof, which at least partially solve the above technical problems.

[0006] To achieve the above object, the first aspect of the present application provides a power control method of an agricultural machine, comprising: estimating an initial demand power generation of the agricultural machine according to a current whole machine operation condition of the agricultural machine; obtaining a compensation correction value associated with power generation efficiency based on a power difference between a power generation request power of the agricultural machine at a previous time and an actual power generation power of the agricultural machine at a current time; and correcting the initial demand power generation based on the compensation correction value and a correction coefficient associated with atmospheric pressure to obtain a final demand power generation.

[0007] In the embodiments of the present application, before the initial demand power generation of the agricultural machine is estimated, the power control method further comprises: determining the current whole machine operation condition to be one of a working condition, a grain unloading condition and a field moving condition according to travel information of the agricultural machine; in the working condition, the demand power generation of the agricultural machine comprises power required for running of a walking motor and all working motors; in the grain unloading condition, the demand power generation of the agricultural machine comprises power required for running of a grain unloading motor, wherein the all working motors comprise the grain unloading motor; and in the field moving condition, the demand power generation of the agricultural machine comprises power required for running of the walking motor.

[0008] In the embodiments of the present application, the initial demand power generation of the agricultural machine is estimated by: estimating hydraulic system demand power of the agricultural machine in a corresponding whole machine operation condition; estimating motor drive system demand power of the agricultural machine in the corresponding whole machine operation condition, wherein the motor drive system comprises a drive system for the walking motor and a drive system for the working motor; and adding the hydraulic system demand power and the motor drive system demand power to obtain the initial demand power generation.

[0009] In the embodiments of the present application, the initial demand power generation is corrected by the following formula to obtain the final demand power generation:

[0010]

[0011]

[0012] p req_i =p0+ΔP;

[0013] In the formula, p req is the final demand power generation, p0 is the initial demand power generation, ΔP is the compensation correction value, p req_i is an intermediate value after correction based on the compensation correction value, K is the correction coefficient, B is a standard atmospheric pressure threshold, and P is a current atmospheric pressure.

[0014] In the embodiments of the present application, after the final demand power is obtained, the method further comprises: matching a high-efficiency interval in a MAP characteristic curve of an engine of the agricultural machine based on the final demand power, and controlling the engine to operate at a speed corresponding to the matched high-efficiency interval; determining a torque of a generator of the agricultural machine through a MAP characteristic curve of the generator, so that an actual power generation point of the generator is in a high-efficiency interval in the MAP characteristic curve of the generator; and optimizing the speed of the engine and the torque of the generator in combination with a state of charge (SOC) of a power battery of the agricultural machine.

[0015] In the embodiments of the present application, the optimization of the speed of the engine and the torque of the generator in combination with the state of charge (SOC) of the power battery of the agricultural machine comprises: when the SOC is in a preset battery high-efficiency interval, determining whether a power difference between a power generation request power at a previous time and an actual power generation power at a current time of the agricultural machine is within a battery charging range, if yes, maintaining the speed of the engine and the torque of the generator unchanged, otherwise, re-matching a high-efficiency interval in the MAP characteristic curve of the generator and the MAP characteristic curve of the engine in combination with a state of power (SOP) of the battery and the actual power generation power, to obtain optimized speed of the engine and torque of the generator; and when the SOC is out of or does not reach the battery high-efficiency interval, determining whether the power difference is within a battery discharging range, if yes, maintaining the speed of the engine and the torque of the generator unchanged, otherwise, re-matching a high-efficiency interval in the MAP characteristic curve of the generator and the MAP characteristic curve of the engine in combination with the state of power (SOP) of the battery and the actual power generation power, to obtain optimized speed of the engine and torque of the generator.

[0016] In the embodiments of the present application, the power control method further comprises: obtaining a motor feedback power of the agricultural machine during braking or operation of a motor stop; determining a feedback torque based on the motor feedback power; and compensating the torque of the engine by the feedback torque.

[0017] The second aspect of the present application provides a power control device of an agricultural machine, comprising: a memory configured to store instructions; and a processor configured to call the instructions from the memory and capable of realizing any of the above power control methods when the instructions are executed.

[0018] The third aspect of the present application provides an agricultural machine comprising any of the above power control devices.

[0019] The fourth aspect of the present application provides a machine readable storage medium, which stores instructions for causing a machine to execute any of the above power control methods.

[0020] By the above technical solution, the present application fully considers the influence of power generation efficiency and atmospheric pressure on power generation power following accuracy, and proposes a corresponding compensation correction scheme, so that the actual power generation power is infinitely close to the target power generation power, meeting the driving and running requirements of agricultural machinery.

[0021] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0022] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, and are used together with the following specific embodiments to explain the present application, but do not constitute a limitation on the present application. In the drawings:

[0023] Fig. 1(a) schematically shows the power system architecture of a conventional fuel harvester;

[0024] Fig. 1(b) schematically shows the power system architecture of a range extender hybrid harvester;

[0025] Fig. 1(c) and Fig. 1(d) respectively schematically show the engine fuel economy effect of the fuel machine type of Fig. 1(a) and the hybrid machine type of Fig. 1(b);

[0026] Figure 2 Fig. 1(c) and Fig. 1(d) respectively schematically show the engine fuel economy effect of the fuel machine type of Fig. 1(a) and the hybrid machine type of Fig. 1(b);

[0027] Figure 3 Fig. 1(c) and Fig. 1(d) respectively schematically show the engine fuel economy effect of the fuel machine type of Fig. 1(a) and the hybrid machine type of Fig. 1(b);

[0028] Figure 4 Fig. 1(c) and Fig. 1(d) respectively schematically show the engine fuel economy effect of the fuel machine type of Fig. 1(a) and the hybrid machine type of Fig. 1(b);

[0029] Figure 5 Fig. 1(c) and Fig. 1(d) respectively schematically show the engine fuel economy effect of the fuel machine type of Fig. 1(a) and the hybrid machine type of Fig. 1(b);

[0030] Fig. 6(a) and Fig. 6(b) respectively schematically show the engine characteristic curve and the generator characteristic curve;

[0031] Figure 7 Fig. 1(c) and Fig. 1(d) respectively schematically show the engine fuel economy effect of the fuel machine type of Fig. 1(a) and the hybrid machine type of Fig. 1(b);

[0032] Figure 8A schematic diagram of an example energy recovery control according to embodiments of the application is shown schematically; and

[0033] Figure 9 A structural block diagram of a power control device according to embodiments of the application is shown schematically. DETAILED DESCRIPTION

[0034] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. It should be understood that the specific implementation manners described herein are merely used to explain and illustrate the embodiments of the present application, and should not be used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0035] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are merely used to explain the relative positional relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directional indications also change accordingly.

[0036] In addition, if the embodiments of the present application involve descriptions such as "first", "second", etc., the descriptions of "first", "second", etc. are merely for description purposes, and should not be understood as indicating or implying the relative importance of the technical features indicated or the number of the technical features indicated. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that a person of ordinary skill in the art can realize it, and when the combination of technical solutions contradicts each other or cannot be realized, it should be considered that the combination of technical solutions does not exist, and is also not within the scope of protection claimed by the present application.

[0037] The scheme of the embodiments of the present application is directed to agricultural machinery. For ease of description, an example of a range-extending hybrid harvester is taken here, and the system architecture of the agricultural machinery is first specifically introduced, so that those of ordinary skill in the art can better understand the present application.

[0038] Fig. 1(b) is a schematic diagram of the power system architecture of the extended-range hybrid harvester, the engine crankshaft output is directly connected to the generator system, and during walking and working, the generator drives the generator to generate electricity, providing power for each driving module in the high-voltage power loop, and at the same time, the power battery is charged. The front and rear axles and the fan are controlled by a multi-in-one drive control system, which is more compact in arrangement. At the same time, other modules such as the header, the bridge, the reel, the intermediate shaft, etc. are replaced by motor direct drive. Therefore, compared with the traditional fuel harvester of Fig. 1(a), the extended-range hybrid harvester adds motors at multiple power take-off ports, greatly simplifies the transmission mechanism and transmission circuit, and reduces the power loss in the transmission process. Moreover, through the extended-range hybrid control system, it is easier to achieve reasonable energy distribution to each module during operation, so that the whole machine has higher working efficiency. As shown in Figs. 1(c) and 1(d), the engine fuel economy effect of the fuel harvester of Fig. 1(a) and the hybrid harvester of Fig. 1(b) is shown, respectively, and the latter has better power performance and energy consumption performance.

[0039] Therefore, the energy management strategy is crucial for the extended-range hybrid harvester. Through an efficient and stable energy management strategy, the whole machine can have better performance in power performance and energy consumption performance, and power control is part of the energy management strategy.

[0040] However, compared with conventional new energy vehicles, agricultural machinery not only requires walking on various road conditions, but also requires high efficiency operation, which makes agricultural machinery have multiple working parts, such as the fan and the reel shown in Fig. 1(b), and has special whole machine operating conditions. When designing the energy management strategy, it is necessary to understand the whole machine operating conditions of the agricultural machinery. Therefore, taking the extended-range hybrid harvester of Fig. 1(b) as an example, the working conditions, the transfer conditions and the unloading conditions are introduced as follows.

[0041] In the working condition, the header is lifted to a certain height by the system, the drum motor and the bridge are started to the set speed, and the reel is adapted to the specific speed according to the real-time vehicle speed to meet the changing crop feeding amount. The whole machine responds to the target speed of the steering handle to maintain the working speed stable during the working process. At this time, the power module loop includes the walking motor, the battery, the generator, the drum and other working parts (fan motor, reel motor, bridge motor, intermediate shaft, etc.).

[0042] In the unloading condition, this scene is generally static unloading, that is, the grain in the silo is transported to the synchronous grain transport vehicle through the operation of the cage. Only the unloading motor drives the cage and the elevator during the unloading process, and the actual demand power is small, which can usually be provided by the power battery.

[0043] In the field transfer working condition, the scene is mainly a walking scene, and the motors of other working modules have no power demand. Therefore, the main working components are the engine, the generator, the power battery and the walking motor. The power demand during walking is complex, and factors such as road conditions, walking slope size, whole machine mass and speed all affect the whole machine power, and the overall power is relatively small but the linear span is relatively large.

[0044] In view of these complex whole machine operation conditions, an energy management strategy needs to be designed accordingly, and in the design of the energy management strategy, the power follow-up control method is used to calculate the power generation power of the generator. However, in the conventional power follow-up control method, the influence of factors such as power generation delay and low atmospheric pressure is not considered, and the determined optimal fuel consumption curve cannot meet the actual driving and operation requirements. Therefore, the present embodiment proposes a new power control scheme for agricultural machinery.

[0045] Figure 2 The flowchart of the power control method of the agricultural machinery according to the embodiment of the present application is schematically shown. As shown in the figure, Figure 2 The power control method can include the following steps:

[0046] Step S100, according to the current whole machine operation condition of the agricultural machinery, the initial demand power generation power of the agricultural machinery is estimated.

[0047] It should be noted that the current whole machine operation condition can be determined to be one of the working condition, the unloading condition and the field transfer condition according to the information about vehicle driving indicated by the driving information of the agricultural machinery, such as the whole machine throttle signal, the brake signal, the gear signal, the working mode signal and other conventional information (throttle opening, steering wheel angle, vehicle speed, etc.), and then the initial demand power generation power is calculated correspondingly.

[0048] According to the above introduction of the three working conditions, it can be known that: in the working condition, the demand power generation power of the agricultural machinery includes the power required for the walking motor and all working motors to operate; in the unloading condition, the demand power generation power of the agricultural machinery includes the power required for the unloading motor to operate, wherein the all working motors include the unloading motor, that is, the power demand of the walking motor and other working motors does not need to be considered in this working condition; in the field transfer working condition, the demand power generation power of the agricultural machinery includes the power required for the walking motor to operate, that is, the power demand of the working motor does not need to be considered in this field transfer working condition.

[0049] For the step S100, the initial demand power of the agricultural machine can be estimated by estimating the hydraulic system demand power of the agricultural machine in the corresponding whole machine operating condition, estimating the motor drive system demand power of the agricultural machine in the corresponding whole machine operating condition, wherein the motor drive system includes a drive system for the walking motor and a drive system for the working motor, and adding the hydraulic system demand power and the motor drive system demand power to obtain the initial demand power. The hydraulic system power demand includes the power demand of components such as brakes and steering lamps that depend on hydraulic control, and the motor drive system power demand can refer to FIG. 1(b) and involves the power demand of the walking motor, the drum motor, the over-bridge motor, the fan, the harrow, the header motor, the power battery, etc.

[0050] In addition, regarding the specific power demand, it can be determined according to the driving intention and the driving information, for example:

[0051] 1) The power demand Pm of the walking motor is estimated according to the real-time opening degree of the accelerator, the opening degree change rate, and the current speed of the walking motor.

[0052] 2) The demand power Pg of the drum motor, Pb of the over-bridge motor, and Pw of the harrow motor are estimated according to the current speed of the whole vehicle and the change rate of the current speed.

[0053] 3) The fan motor power Pf of the fan at the current time is calculated (the fan power requires constant speed, and the power changes little in the scene of small-range switching of speed, so the actual power output is taken as the target demand power).

[0054] 4) The power demand Ps of other components is calculated.

[0055] The determination method of the power demand of each component is conventional, and therefore will not be described below.

[0056] It can be seen that the estimated initial demand power and the final generator power can both reflect the whole machine state, which can be understood as the whole machine demand power corresponding to different stages in the following.

[0057] Step S200, based on the power difference between the power generation request power of the agricultural machine at the last time and the actual power generation power at the current time, a compensation correction value associated with the power generation efficiency is obtained.

[0058] For example, in the working condition, the extended range architecture allows the engine and other moving mechanisms to be decoupled. Therefore, the engine speed and generator torque can be dynamically adjusted according to the state and trend of the whole machine, so that the generated power follows the demand power of the whole machine. And the step S200 considers the influence of the delay of power generation (i.e. the power generation efficiency) on the power following accuracy, and proposes a compensation correction value for power compensation. The calculation process of the compensation correction value is, for example: calculating the generated request power p rreq and the actual generated power P real at the current time, and obtaining the compensation correction value ΔP of the generated power by the actual power difference between the two, where a positive value represents enhancement and a negative value represents reduction. By applying the compensation correction value to the next calculation period, the actual generated power can be made to approach the requested generated power, so as to compensate for the influence of the power generation efficiency and errors.

[0059] Step S300, based on the compensation correction value and the correction coefficient associated with the atmospheric pressure, correcting the initial demand generated power to obtain the final demand generated power.

[0060] It should be noted that the atmospheric pressure determines the oxygen content of the same intake amount of the engine, and thus it is negatively related to the fuel combustion efficiency of the engine, so the influence of the atmospheric pressure needs to be considered in the actual operation of the agricultural machinery.

[0061] Therefore, by combining steps S200 and S300, the initial demand generated power can be corrected by the following formula:

[0062]

[0063]

[0064] p req_i = p0+ ΔP

[0065] In the formula, p req is the final demand generated power, p0 is the initial demand generated power, ΔP is the compensation correction value, i.e. ΔP = p rreq -p real , p req_i is the intermediate value after correction based on the compensation correction value, K is the correction coefficient associated with the atmospheric pressure, B is the standard atmospheric pressure threshold, and P is the current atmospheric pressure.

[0066] Therefore, for the above steps S100-S300, in combination with the power generation correction schematic diagram of Figure 3 , after obtaining the final demand generated power, the energy management strategy can be further designed.

[0067] In the preferred embodiments of the present application, in combination Figure 3 and as shown in FIG. 3, the designed energy management strategy can optimize the engine speed and the generator torque by the following steps: Figure 4

[0068] Step S401, match the high-efficiency interval in the engine MAP characteristic curve of the agricultural machine based on the final demand power generation power, and control the engine to operate at the speed corresponding to the matched high-efficiency interval.

[0069] For example, the whole machine power demand (i.e. the final demand power generation power, including the estimated initial demand power generation power, the compensation correction power of the last period) is calculated, and then combined with the charging and discharging characteristics of the SOC and the generator MAP characteristic curve, the high-efficiency interval corresponding to the final demand power generation power can be found in the engine MAP characteristic curve, so that the engine operates at the corresponding speed of the high-efficiency interval. It should be noted that the whole machine power demand can also include the friction power of the engine, which represents the process loss power output by the engine, including transmission loss power, shaft end loss power, etc.

[0070] Step S402, determine the torque of the generator through the generator MAP characteristic curve of the agricultural machine, so that the actual power generation power point of the generator is in the high-efficiency interval in the generator MAP characteristic curve.

[0071] Step S403, optimize the speed of the engine and the torque of the generator in combination with the SOC of the power battery of the agricultural machine.

[0072] In this way, steps S402 and S403 determine the initial engine speed and generator torque using the motor characteristic curve, and then step S403 optimizes in combination with the battery SOC. In more preferred embodiments of the present application, the optimization method is, for example:

[0073] When the SOC is in the preset battery high-efficiency interval, it is judged whether the power difference between the power generation request power of the agricultural machine at the last moment and the actual power generation power at the current moment is within the battery charging range, if yes, the speed of the engine and the torque of the generator are maintained, otherwise, in combination with the SOP (battery power state) of the agricultural machine and the actual power generation power, the high-efficiency interval is re-matched in the generator MAP characteristic curve and the engine MAP characteristic curve to obtain the optimized speed of the engine and the torque of the generator.

[0074] ​When the SOC exceeds or does not reach the battery high-efficiency range, it is determined whether the power difference is within the battery discharge range. If so, the engine speed and the generator torque are maintained unchanged. Otherwise, based on the battery power state SOP of the agricultural machinery and the actual generated power, the high-efficiency range is re-matched in the generator MAP characteristic curve and the engine MAP characteristic curve to obtain the optimized engine speed and generator torque.

[0075] For example, if Figure 5 As shown in the figure, the optimal operating SOC target threshold region [SOCmin, SOCmax] under SOC conditions is defined by the battery performance parameter curve. The power battery has the best charge and discharge performance in the target threshold region, which can maximize the use of battery performance to supplement the generator's transient response curve, making the two complement each other well and ultimately obtaining ideal generator torque and engine speed information. Figure 5 , Pbat is used to represent a power threshold window that allows the power battery to be charged to discharged under the current SOC, temperature and other conditions. Therefore, the battery state, that is, the current battery SOC, can be properly charged to the power threshold window of proper discharge. Since the target SOC has a dynamic stable interval, the size of the SOC value determines the boundary of the power threshold window (the larger the SOC, the larger the lower boundary of the power threshold, thus biased towards the charging trend; the smaller the SOC, the larger the upper boundary of the power threshold window, and the more biased towards the discharge trend). At this time, Figure 5 The power difference actually refers to the difference between the last power generation request value and the current power generation request value. If this difference meets Pbat in the previous step, it is considered that the current system can meet the power requirement and the system does not make any adjustments. Otherwise, a new high-efficiency power point needs to be recalculated.

[0076] According to the engine and generator characteristic curves shown in Figure 6(a) and Figure 6(b), there is a transmission mechanism from the engine to the generator, that is, a gearbox with a transmission ratio of K. During the matching process, attention should be paid to the matching relationship between torque and speed. It is necessary to obtain a speed and torque range corresponding to the total power output of the engine (speed and torque determine a mapping point) that covers the entire machine power. At the same time, these ranges are also highly efficient in the generator characteristics (or relatively high, with the second highest priority, and the mapping optimization process is mainly based on the engine). In this way, refer to Figure 5 After determining the power difference between the requested power at the previous moment and the actual power generation at the current moment, the system will prioritize whether there are other efficient points among the determined mapping points that meet the current scenario, assuming the current speed remains unchanged. Otherwise, it will search left (towards low power) or right (towards high power) until it finds a suitable mapping point that meets the current power demand.

[0077] Back toFigure 3 The energy management strategy further comprises power output matching of the power battery and the generator. For example, in the unloading working condition, since the unloading working condition has small power and single demand, the unloading working condition is mainly considered according to the SOC to distinguish. When the SOC is less than SOCmin, the engine is started, the generator is considered to charge the power battery in the case of supplying power to the unloading mechanism, and at this time, the engine needs to find a suitable efficiency interval. If the SOC is greater than SOCmax, the engine is stopped, and the unloading power is mainly supplied by the power battery. Therefore, in the case of high efficiency of the whole machine battery, the unloading working condition has relatively high efficiency.

[0078] That is, according to the SOC of the power battery, when the SOC is greater than the set threshold, the engine is turned off, and the power battery is used to drive the unloading related modules to unload. When the SOC is less than the set threshold, according to the effective average power of the unloading process and the current power of the battery, the speed of the engine and the power generation torque of the generator are set, so that the engine has high efficiency at the speed, and at this time the engine is the power source of the whole machine, part of which is used to maintain the demand of the unloading process, and the other part is used to charge the battery.

[0079] For example, in the field transfer working condition, the walking power is mainly used as the power demand of the whole vehicle, and there is no power input except the hydraulic system. At this time, the power of the whole vehicle is realized in a rule and multi-condition constraint manner, for example, the power battery threshold of the field transfer scene can be defined. When the power battery SOC threshold is large, the walking process can be in a pure electric mode, that is, the battery is the only power source. When the battery SOC threshold is small, it is consistent with the working condition, which can be understood by referring to the detailed description of the foregoing Figure 2 and Figure 4 . That is, the low-power battery needs to increase the charging weight, and in the overall trend, a dynamic balance state can be reached.

[0080] After the engine speed and the generator torque are determined in the foregoing, the VCU (vehicle controller) of the agricultural machine sends the target speed to the engine ECU to respond to the power demand at the next moment. At the same time, the VCU sends the target generator torque to the generator MCU in a single-step cumulative manner (the step size is determined according to the actual field calibration), so as to reduce the crankshaft impact caused by the rapid mutation of the engine load, and also make the engine respond at a smooth rate, avoiding stall caused by overload.

[0081] In the preferred embodiment, as shown in Figure 7 , the above-mentioned energy management strategy can further comprise:

[0082] Step S701, acquiring the motor feedback power of the agricultural machine in the braking process or the working motor shutdown process.

[0083] Step S702, determining the feedback torque based on the motor feedback power.

[0084] Step S703, compensating the torque of the engine by the feedback torque.

[0085] For the above steps S701-S703, the following will be specifically introduced by examples, Figure 8 is an example of the principle diagram of energy recovery control. As Figure 8 shown, wherein the range-extended hybrid harvester of FIG. 1(b) is taken as an example, the recovery power (i.e. motor feedback power) is the kinetic energy of the drum shutdown process and the harvester whole machine walking brake shutdown process recovered through the corresponding motor, combined with the characteristic efficiency η and rotational inertia J of the drum motor or the walking motor at the current speed, the recoverable power value within the calibration time and the theoretical power generation torque M after the calibration time are calculated, and the specific algorithm is shown in the following formula:

[0086]

[0087] Since the target SOC and the SOP of the battery, i.e. the battery state, actually determine the charging power of the whole machine power battery, after obtaining the theoretical power generation torque, the feedback torque needs to be output in combination with the current battery state, the current state of the whole machine generator, etc. For example, under the current battery SOC, the power threshold window of appropriate charging to appropriate discharging can be appropriately charged. Since the target SOC exists a dynamic stable interval, the size of the SOC value determines the boundary of the power threshold window (the larger the SOC, the larger the lower boundary of the power threshold, thereby tending to charge; the smaller the SOC, the larger the upper boundary of the power threshold window, thereby tending to discharge). At this time, the feedback torque needs to meet: the output torque is within the limit torque range of the generator; the output torque power is converted through efficiency, and the generated current cannot cause the power battery to overshoot; the smoothness and non-jerk of the whole vehicle during the loading and braking process need to be met.

[0088] Figure 8 The energy recovery interference compensation in the above formula mainly refers to the compensation of efficiency conversion. The theoretical recovery power value will be different from the conversion value due to efficiency reasons, so this part needs to be added to the recovery power input through additional compensation, and finally acts on the torque of the generator.

[0089] In this way, by optimizing the energy recovery strategy, the existing energy management strategy is enriched, so that the motor feedback power is used in the whole machine braking process and the drum shutdown process to charge the power battery.

[0090] In summary, the power control method of the embodiment of the application fully considers the influence of power generation efficiency and atmospheric pressure on following accuracy in the power following process, proposes to make compensation correction in the next calculation period, so that the actual power generation power infinitely approaches the target power generation power, avoids the situation that the battery appears overcharge or overdischarge due to the large difference between the target power generation power and the actual power generation power, and is beneficial to the service life of the battery. Moreover, the embodiment of the application realizes the target power generation power correction, which can ensure sufficient power response of the entire hybrid power system on the one hand, and can also ensure good driving following performance on the premise of optimal fuel consumption and NVH performance on the other hand. That is, on the premise of ensuring the output power, the stability of the engine is met, and the energy saving target is reached. In addition, the embodiment of the application also introduces an energy recovery strategy, enriches the entire energy management process, and is more helpful to achieve the energy saving target.

[0091] Figure 9 A structural block diagram of a power control device of an agricultural machine according to an embodiment of the application is schematically shown. As shown in the figure, the power control device can include a memory configured to store instructions, and a processor configured to call the instructions from the memory and capable of realizing the power control method described above when executing the instructions. In an example, the power control device is, for example, a whole vehicle controller of a harvester or a separately configured controller. Figure 9

[0092] The embodiment of the application also provides an agricultural machine including the power control device described above. The agricultural machine is, for example, the extended-range hybrid harvester described above, but is not limited thereto, and in other examples, can also be a baler, a transplanter or various types of tractor, etc.

[0093] The embodiment of the application also provides a machine readable storage medium having instructions stored thereon for causing a machine to execute the power control device described above.

[0094] Those skilled in the art should understand that the embodiments of the application can be provided as a method, a system or a computer program product. Therefore, the application can adopt a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the application can adopt the form of a computer program product implemented on one or more computer usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

[0095] ​The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks or in conjunction with the flowcharts described above.

[0096] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks or in conjunction with the flowcharts described above.

[0097] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks or in conjunction with the flowcharts described above.

[0098] In one typical configuration, the computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0099] The memory can include non-persistent memory and / or volatile memory, such as random access memory (RAM) and / or cache memory, for storing, in general, instructions to be executed by the processor and / or data received via a communication interface. The memory can also include non-volatile memory, such as read only memory (ROM) and / or flash memory, for storing, in general, static instructions and / or data that is not lost when the computing device is turned off or otherwise ceases to operate for any period of time. The memory can be internal or external to the computing device.

[0100] Computer-readable media includes permanent and non-permanent, movable and non-movable media that can implement information storage by any method or technology. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette, disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information accessible by a computing device. According to the definition herein, computer-readable media does not include transitory media such as modulated data signals and carriers.

[0101] It should also be noted that the terms "comprising", "containing", or any other variant thereof are intended to cover non-exclusive inclusions, so that a process, method, article or apparatus that includes a list of elements does not only include those elements, but also includes other elements not explicitly listed, or further includes elements inherent in such a process, method, article or apparatus. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article or apparatus that includes the element.

[0102] The above only is an embodiment of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the scope of claims of the present application.

Claims

1. A power control method for agricultural machinery, characterized in that: include: estimating the initial required power generation power of the agricultural machinery based on the current operating condition of the agricultural machinery; obtaining a compensation correction value associated with power generation efficiency based on a power difference between a power generation request of the agricultural machine at a previous moment and an actual power generation of the agricultural machine at a current moment; Correcting the initial required power generation power based on the compensation correction value and a correction coefficient associated with the atmospheric pressure to obtain a final required power generation power; Matching a high-efficiency operating range in a MAP characteristic curve of an engine of the agricultural machinery based on the final required generated power, and controlling the engine to operate at a speed corresponding to the matched high-efficiency range; Determining the torque of the generator by using a MAP characteristic curve of the generator of the agricultural machinery so that the actual power generation point of the generator is within a high efficiency range of the MAP characteristic curve of the generator; as well as The engine speed and the generator torque are optimized in combination with the state of charge (SOC) and the state of power (SOP) of the power battery of the agricultural machinery.

2. The power control method according to claim 1, wherein: Before estimating the initial required power generation power of the agricultural machinery, the power control method further includes: determining, based on the driving information of the agricultural machinery, that the current operating condition of the entire machine is one of an operating condition, a grain unloading condition, and a field transfer condition; Under the operating conditions, the required power generation power of the agricultural machinery includes the power required for the operation of the travel motor and all the operating motors, wherein all the operating motors include the grain unloading motor; In the grain unloading condition, the required power generation power of the agricultural machinery includes the power required for the operation of the grain unloading motor; Under the field transfer condition, the required power generation power of the agricultural machinery includes the power required for the operation of the travel motor.

3. The power control method according to claim 2, wherein: Estimating the initial required power generation of the agricultural machinery includes: estimating the required power of the hydraulic system of the agricultural machinery under corresponding whole-machine operating conditions; estimating the power requirement of the motor drive system of the agricultural machinery under corresponding whole-machine operating conditions, wherein the motor drive system includes a drive system for the travel motor and a drive system for the working motor; and The required power of the hydraulic system and the required power of the motor drive system are added together to obtain the initial required power generation power.

4. The power control method according to claim 1, wherein: The initial required power generation power is corrected using the following formula to obtain the final required power generation power: ； ； ； Where, To obtain the final required power generation power, The power generated for the initial demand, is the compensation correction value, is the intermediate value corrected based on the compensation correction value, K is the correction coefficient, B is the standard atmospheric pressure threshold, and P is the current atmospheric pressure.

5. The power control method according to claim 1, wherein: The optimizing the engine speed and the generator torque in combination with the state of charge (SOC) and the state of power (SOP) of the power battery of the agricultural machinery includes: When the SOC is in a preset battery high-efficiency range, determining whether a power difference between a power generation request of the agricultural machinery at a previous moment and an actual power generation of the agricultural machinery at a current moment is within a battery charge and discharge range; if so, maintaining the engine speed and the generator torque unchanged; otherwise, re-matching the high-efficiency range in the generator MAP characteristic curve and the engine MAP characteristic curve based on the battery power state SOP of the agricultural machinery and the actual power generation, so as to obtain optimized engine speed and generator torque; and When the SOC exceeds or does not reach the battery high-efficiency range, it is determined whether the power difference is within the corresponding battery charging range or battery discharging range. If so, the engine speed and the generator torque are maintained unchanged. Otherwise, based on the battery power state SOP of the agricultural machinery and the actual generated power, the high-efficiency range is re-matched in the generator MAP characteristic curve and the engine MAP characteristic curve to obtain the optimized engine speed and generator torque. The power control method according to claim 1 , wherein: The power control method further includes: Obtaining the motor feedback power of the agricultural machinery during a braking process or a shutdown process of the operating motor; determining a feedback torque based on the motor feedback power; and The torque of the engine is compensated by the feedback torque.

7. A power control device for agricultural machinery, characterized in that: include: a memory configured to store instructions; as well as A processor is configured to call the instructions from the memory and implement the power control method according to any one of claims 1 to 6 when executing the instructions.

8. An agricultural machine, characterized in that: Includes the power control device as claimed in claim 7.

9. A machine-readable storage medium, characterized in that The machine-readable storage medium stores instructions, which are used to enable a machine to execute the power control method according to any one of claims 1 to 6.

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