阅读说明：本技术 用于起重机的负功率控制方法、设备、系统及起重机 (Negative power control method, equipment and system for crane and crane ) 是由 李英智 胡廷江 谭松涛 陈嘉 李怀福 于 2021-06-17 设计创作，主要内容包括：本发明实施例提供一种用于起重机的负功率控制方法、设备、系统及起重机,属于工程机械技术领域。所述起重机包括发动机、至少一个闭式系统及开式系统,通过获取所述发动机的摩擦扭矩百分比及实际扭矩百分比；根据所述摩擦扭矩百分比及所述实际扭矩百分比确定实际负载率；根据所述实际负载率和预设负载率确定所述开式系统的负载投入量,使得所述开式系统根据所述负载投入量吸收所述闭式系统产生的负功率。其中,将发动机的扭矩百分比作为参数控制开式系统的负载投入量,避免了起重机在采用复合动作进行重物就位时,因变幅机构吸收负功率、其他闭式系统吸收或产生负功率导致的负功率控制不准确,实现了复合动作工况下负功率的精确控制。(The embodiment of the invention provides a negative power control method, equipment and system for a crane and the crane, and belongs to the technical field of engineering machinery. The crane comprises an engine, at least one closed system and an open system, and the percentage of friction torque and the percentage of actual torque of the engine are obtained; determining an actual load rate according to the friction torque percentage and the actual torque percentage; and determining the load input amount of the open system according to the actual load rate and a preset load rate, so that the open system absorbs the negative power generated by the closed system according to the load input amount. The torque percentage of the engine is used as a parameter to control the load input amount of the open system, so that the problem that when the crane performs composite action to place a heavy object, the negative power control is inaccurate due to the fact that the amplitude variation mechanism absorbs negative power and other closed systems absorb or generate negative power is solved, and the negative power is accurately controlled under the working condition of the composite action.)

1. A negative power control method for a crane, the crane comprising an engine, at least one closed system and an open system, characterized in that the negative power control method comprises:

acquiring a friction torque percentage and an actual torque percentage of the engine;

determining an actual load rate according to the friction torque percentage and the actual torque percentage;

and determining the load input amount of the open system according to the actual load rate and a preset load rate, so that the open system absorbs the negative power generated by the closed system according to the load input amount.

2. The negative power control method of claim 1, wherein said determining a load input of the open system based on the actual load rate and a preset load rate comprises:

obtaining the load change rate of the open system according to the actual load rate and a preset load rate by using an incremental PID control model;

and obtaining the load input amount of the open system according to the load change rate and a preset load amount.

3. The negative power control method of claim 2, wherein said deriving the rate of change of load of the open system from the actual load rate and a preset load rate using an incremental PID control model comprises:

calculating a deviation value of the actual load rate and the preset load rate;

and inputting the deviation value into the incremental PID control model to obtain the load change rate of the open system.

4. The negative power control method of any of claims 1-3, further comprising:

detecting whether the crane is in a hoisting and falling state;

and acquiring a preset load from the open system under the condition that the crane is in a hoisting and falling state.

5. The negative power control method of any of claims 1-3, wherein said determining an actual load rate as a function of the friction torque percentage and the actual torque percentage comprises:

judging whether the actual torque percentage is greater than zero;

and taking the difference between the actual torque percentage and the friction torque percentage as an actual load factor when the actual torque percentage is larger than zero.

6. A negative power control apparatus for a crane, comprising:

a memory for storing a negative power control program for the crane;

a processor configured to call the negative power control program for a crane from the memory so that the processor can execute the negative power control method for a crane according to any one of claims 1 to 5.

7. A negative power control system for a crane, comprising:

an engine;

an open system;

at least one closed system; and

negative power control device for a crane according to claim 6.

8. The negative power control system of claim 7, wherein the at least one closed system, the engine, and the open system are in communication with the negative power control device.

9. The negative power control system as recited in claim 7, further comprising a horn, the negative power control device further for determining a load input to the open system when the at least one closed system and the horn are simultaneously actuated.

10. A crane comprising a negative power control system for a crane according to any one of claims 7 to 9.

Technical Field

The invention relates to the technical field of engineering machinery, in particular to a negative power control method, equipment and system for a crane and the crane.

Background

At present, a hoisting mechanism of a crane or a crawler crane with large tonnage usually adopts a plurality of closed hoisting systems (hereinafter referred to as closed systems), and when a heavy object is in place, the closed system and a luffing mechanism are required to perform combined action, a plurality of closed systems perform combined action or a plurality of closed systems and a luffing mechanism perform combined action.

In the prior art, the negative power generated when the heavy object of the closed system falls is absorbed by the open system, and the scheme is only suitable for controlling the negative power under the working condition of single closed system action. In specific application, if a composite action is adopted when a heavy object is in place, the luffing mechanism may absorb negative power, other closed systems may absorb negative power and may also generate negative power, and if the negative power control scheme in the prior art is directly used for the working condition of the composite action, problems of too large or too small load input amount, improper power matching and the like in an open system may occur.

Disclosure of Invention

The invention mainly aims to provide a method, equipment and a system for controlling negative power of a crane and the crane, and aims to solve the technical problem that the crane in the prior art cannot effectively control the negative power when a heavy object is in place by adopting compound action.

In order to achieve the above object, a first aspect of the present invention provides a negative power control method for a crane, comprising the steps of:

acquiring the friction torque percentage and the actual torque percentage of the engine;

determining an actual load rate according to the friction torque percentage and the actual torque percentage;

and determining the load input amount of the open system according to the actual load rate and the preset load rate so that the open system absorbs the negative power generated by the closed system according to the load input amount.

In the embodiment of the invention, the determining of the load input amount of the open system according to the actual load rate and the preset load rate comprises the following steps:

obtaining the load change rate of the open system by using an incremental PID control model according to the actual load rate and the preset load rate;

and obtaining the load input amount of the open system according to the load change rate and the preset load amount.

In the embodiment of the present invention, an incremental PID control model is used to obtain the load change rate of the open system according to the actual load rate and the preset load rate, which includes:

calculating a deviation value of the actual load rate and the preset load rate;

and inputting the deviation value into an incremental PID control model to obtain the load change rate of the open system.

In the embodiment of the present invention, the control method further includes:

detecting whether the crane is in a hoisting falling state;

and acquiring a preset load from the open system under the condition that the crane is in a winding and falling state.

In the embodiment of the invention, the step of determining the actual load rate according to the percentage of the friction torque and the percentage of the actual torque comprises the following steps:

judging whether the actual torque percentage is greater than zero;

in the case where the actual torque percentage is greater than zero, the difference between the actual torque percentage and the friction torque percentage is taken as the actual load factor.

A second aspect of the present invention provides a negative power control apparatus for a crane, comprising:

a memory for storing a negative power control program for the crane;

a processor configured to call the negative power control program for the crane from the memory so that the processor can perform the above-described negative power control method for the crane.

A third aspect of the invention provides a negative power control system for a crane, comprising:

an engine;

an open system;

at least one closed system; and

the negative power control apparatus for a crane according to the above.

In an embodiment of the invention, at least one of the closed system, the engine and the open system is in communication with a negative power control device.

In the embodiment of the invention, the negative power control system further comprises a luffing mechanism and a negative power control device, and is further used for determining the load input amount of the open system when at least one closed system and the luffing mechanism act simultaneously.

A fourth aspect of the invention provides a crane comprising a negative power control system for a crane as described above.

According to the technical scheme, under the condition that the crane is provided with the engine, at least one closed system and an open system, the friction torque percentage and the actual torque percentage of the engine are obtained; determining an actual load rate according to the friction torque percentage and the actual torque percentage; and determining the load input amount of the open system according to the actual load rate and the preset load rate, so that the open system absorbs the negative power generated by the closed system according to the load input amount. The torque percentage of the engine is used as a parameter to control the load input amount of the open system, so that the problem that when the crane performs composite action to place a heavy object, the negative power control is inaccurate due to the fact that the amplitude variation mechanism absorbs negative power and other closed systems absorb or generate negative power is solved, and the negative power is accurately controlled under the working condition of the composite action.

Additional features and advantages of embodiments of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:

FIG. 1 is a schematic diagram of a negative power control device for a crane in a hardware operating environment according to an embodiment of the present invention;

FIG. 2 is a schematic flow chart of a negative power control method for a crane according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of negative power distribution of the crane according to the embodiment of the invention under a composite action condition;

FIG. 4 is a schematic diagram of negative power distribution of another embodiment of the crane under the composite action working condition according to the embodiment of the invention;

FIG. 5 is a schematic diagram of negative power distribution of the crane according to another embodiment of the present invention under a composite-action condition;

FIG. 6 is a schematic diagram of negative power distribution of a crane according to still another embodiment of the present invention under a composite action condition;

FIG. 7 is a detailed flowchart of step S30 in FIG. 1;

FIG. 8 is a functional block diagram of one embodiment of a negative power control system for a crane of the present invention;

FIG. 9 is a functional block diagram of another embodiment of the negative power control system for a crane of the present invention.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating embodiments of the invention, are given by way of illustration and explanation only, not limitation.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a negative power control device for a crane in a hardware operating environment according to an embodiment of the present invention.

As shown in fig. 1, the negative power control apparatus for a crane may include: a processor 1001, such as a CPU, a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Wherein a communication bus 1002 is used to enable connective communication between these components. The user interface 1003 may comprise a display screen, an input unit such as a keyboard, and the optional user interface 1003 may also comprise a standard wired interface, a wireless interface. The network interface 1004 may optionally include a standard wired interface, a wireless interface (e.g., WI-FI interface). The memory 1005 may be a high speed RAM memory or a stable memory such as a disk memory. The memory 1005 may alternatively be a storage device separate from the processor 1001.

Those skilled in the art will appreciate that the configuration shown in fig. 1 does not constitute a limitation of a negative power control device for a crane and may include more or fewer components than shown, or some components in combination, or a different arrangement of components.

As shown in fig. 1, a memory 1005, which is a kind of computer storage medium, may include therein an operating system, a network communication module, a user interface module, and a negative power control program for a crane.

In the negative power control apparatus for a crane shown in fig. 1, the network interface 1004 is mainly used for data communication with an external network; the user interface 1003 is mainly used for receiving input instructions of a user; the negative power control apparatus for a crane calls a negative power control program for a crane stored in the memory 1005 by the processor 1001 and performs the following operations:

acquiring a friction torque percentage and an actual torque percentage of the engine;

determining an actual load rate according to the friction torque percentage and the actual torque percentage;

and determining the load input amount of the open system according to the actual load rate and a preset load rate, so that the open system absorbs the negative power generated by the closed system according to the load input amount.

Further, the processor 1001 may call a negative power control program for the crane stored in the memory 1005, and also perform the following operations:

obtaining the load change rate of the open system according to the actual load rate and a preset load rate by using an incremental PID control model;

and obtaining the load input amount of the open system according to the load change rate and a preset load amount.

Further, the processor 1001 may call a negative power control program for the crane stored in the memory 1005, and also perform the following operations:

calculating a deviation value of the actual load rate and the preset load rate;

and inputting the deviation value into the incremental PID control model to obtain the load change rate of the open system.

Further, the processor 1001 may call a negative power control program for the crane stored in the memory 1005, and also perform the following operations:

detecting whether the crane is in a hoisting and falling state;

and acquiring a preset load from the open system under the condition that the crane is in a hoisting and falling state.

Further, the processor 1001 may call a negative power control program for the crane stored in the memory 1005, and also perform the following operations:

judging whether the actual torque percentage is greater than zero;

and taking the difference between the actual torque percentage and the friction torque percentage as an actual load factor when the actual torque percentage is larger than zero.

According to the scheme, under the condition that the crane is provided with the engine, at least one closed system and an open system, the friction torque percentage and the actual torque percentage of the engine are obtained; determining an actual load rate according to the friction torque percentage and the actual torque percentage; and determining the load input amount of the open system according to the actual load rate and the preset load rate, so that the open system absorbs the negative power generated by the closed system according to the load input amount. The torque percentage of the engine is used as a parameter to control the load input amount of the open system, so that the problem that when the crane performs composite action to place a heavy object, the negative power control is inaccurate due to the fact that the amplitude variation mechanism absorbs negative power and other closed systems absorb or generate negative power is solved, and the negative power is accurately controlled under the working condition of the composite action.

Based on the hardware structure, the embodiment of the negative power control method for the crane is provided.

Referring to fig. 2, fig. 2 is a schematic flow chart of a negative power control method for a crane according to an embodiment of the present invention.

In this embodiment, the crane comprises an engine, at least one closed system and an open system, and the negative power control method for the crane comprises the following steps:

s10: acquiring the friction torque percentage and the actual torque percentage of the engine;

it should be noted that, for large-tonnage cranes and crawler cranes, the hoisting and lifting mechanism of the crane mostly adopts a closed system, and when the engine adopts a compound action to position a heavy object in the closed system, the distribution of negative power under the compound action working condition is as follows:

referring to fig. 3, under the working condition of only adopting the compound action of the two closed systems, when only the weight G1 descends, the weight G1 generates negative power, the weight G2 and the closed system 2 both consume the negative power, and the rest negative power is absorbed by adjusting the load input amount in the open system; when weight G1 and weight G2 are both lowered, weight G1, weight G2 and closed system 2 all generate negative power, and all the negative power is absorbed by adjusting the amount of load input in the open system.

Referring to fig. 4, under the working condition of a closed system and a combined action of a luffing mechanism, when the weight G1 descends, the weight G1 generates negative power, the luffing mechanism 2 and the luffing mechanism of the weight both consume the negative power, and the residual negative power is absorbed by adjusting the load input amount in the open system.

Referring to fig. 5, under the working condition of the compound action of the three closed systems, when only the weight G1 descends, the weight G1 generates negative power, the weight G2, the closed system 2, the weight G3 and the closed system 3 all consume the negative power, and the rest negative power is absorbed by adjusting the load input amount in the open system; when weight G1, weight G2, and weight G3 all descend, weight G1, weight G2, weight G3, closed system 2, and closed system 3 all generate negative power, and all the negative power is absorbed by adjusting the load input amount in the open system. When the weight G1 descends, one of the weight G2 and the weight G3 descends, and one ascends, the descending weight and the corresponding closed system generate negative power, the ascending weight and the corresponding closed system consume the negative power, and the residual negative power is absorbed by adjusting the load input amount in the open system.

Referring to fig. 6, under the working condition of the combined action of two closed systems and one luffing mechanism, the weight G1 descends to generate negative power, both the luffing mechanism 2 and the weight luffing mechanism consume negative power, the closed system 3 and the weight 3 may consume negative power and also may generate negative power, and the rest negative power is absorbed by adjusting the load input amount in the open system.

It should be noted that, when the engine adopts the compound action to control the heavy object to be in place, and under the condition that the luffing mechanism or other closed systems consume negative power, if the negative power control scheme of a single action in the prior art is directly applied, problems such as too large load input amount in the open system, too high system energy consumption, improper power matching and the like may occur; when at least two heavy objects in the crane are all lowered to generate negative power, if the negative power control scheme of single action in the prior art is directly applied, the load input amount in the open system is possibly too small, and the engine is further subjected to a runaway accident.

In the prior art, when negative power is controlled under the working condition of single closed system action, the output power of an engine is generally adopted as the basis for adjusting the load input amount. The output power calculation formula of the engine in the hydraulic system is as follows: power k flow pressure, where k is a constant. In order to obtain the output power of the engine, the pressure and flow of the hydraulic system need to be detected and used as control parameters. This solution has two disadvantages: firstly, each crane needs single-end matching of flow parameters, the time of the engine negative power control fine matching test needs about 2 weeks, and if the engine negative power control fine matching test is applied to the working condition of composite action, longer matching test time is needed, and the consumed time is about 3 times or more; secondly, the result of the pressure detection is usually a section, and in order to ensure that the load input is sufficient when the pressure is on the right side of the section, the load input value in the section needs to be a value (i.e., a maximum value) matching the right side of the section, and therefore, when the actual pressure is on the left side of the section, the load input is excessive.

In the embodiment, considering the influence of the negative power absorbed by the luffing mechanism, absorbed by other closed systems or generated by negative power on the absorption of the negative power by the open system, the power of the engine is not used as the basis for adjusting the load input amount in the open system, but the torque percentage of the engine is used as the basis for adjusting the load input amount. Compared with a power regulation scheme, the torque percentage of the engine is convenient to read, data are accurate, a large number of parameter matching tests of each crane are not needed, and the debugging time of the crane is shortened. Therefore, the method has the advantages of accurate control, high response speed, effective safety and energy conservation and the like.

In a specific implementation, the torque percentage of the engine is varied in real time, and the friction torque percentage and the actual torque percentage of the engine can be read from an Electronic Control Unit (ECU) of the engine.

S20: determining an actual load rate according to the friction torque percentage and the actual torque percentage;

specifically, it may be determined whether the actual torque percentage is greater than zero, and when the actual torque percentage is greater than zero, the difference between the actual torque percentage and the friction torque percentage is used as the actual load rate, and then the load input amount of the open system is determined according to the actual load rate.

Of course, when the actual torque percentage is less than or equal to zero, it indicates that the engine does not output power, and at this time, the weight may generate negative power due to the decrease, and it is necessary to not only absorb the negative power by using the open system, but also add another safety control scheme, such as controlling the engine to stop running.

S30: and determining the load input amount of the open system according to the actual load rate and the preset load rate so that the open system absorbs the negative power generated by the closed system according to the load input amount.

It can be understood that the preset load rate is a load rate preset by a user, and in a specific implementation, the load input amount may be determined according to a difference between the actual load rate and the preset load rate.

The negative power control method for the crane is not only suitable for large-tonnage cranes and crawler cranes, but also suitable for mobile cranes, and the scheme not only considers the negative torque absorption capacity and safety of the engine, the real-time performance and the compliance of the engine under extreme load working conditions, but also considers the energy consumption characteristics of the system and the reliability problem caused by the heat generated by the power of the engine, thereby realizing multi-objective cooperative optimization control.

In the embodiment, under the condition that the crane is provided with the engine, at least one closed system and an open system, the friction torque percentage and the actual torque percentage of the engine are obtained; determining an actual load rate according to the friction torque percentage and the actual torque percentage; and determining the load input amount of the open system according to the actual load rate and the preset load rate, so that the open system absorbs the negative power generated by the closed system according to the load input amount. The torque percentage of the engine is used as a parameter to control the load input amount of the open system, so that the problem that when the crane performs composite action to place a heavy object, the negative power control is inaccurate due to the fact that the amplitude variation mechanism absorbs negative power and other closed systems absorb or generate negative power is solved, and the negative power is accurately controlled under the working condition of the composite action.

As shown in fig. 7, fig. 7 is a flowchart illustrating an embodiment of step S30 in fig. 2.

The method comprises the following steps:

s31: obtaining the load change rate of the open system by using an incremental PID control model according to the actual load rate and the preset load rate;

in specific implementation, whether the crane is in a hoisting falling state is detected; and under the condition that the crane is in a winding falling state, acquiring a preset load from the open system, and determining the load input amount according to the load change rate and the preset load. When the crane is not in a hoisting and dropping state, it can be determined that there is no load input in the open system, and further, there is no need to control the load input amount.

The PID control model is a control model in which PID control is performed on an increment of a control amount (a difference between the present control amount and the previous control amount). The control quantity in the embodiment is a load rate, and a deviation value between an actual load rate and a preset load rate can be calculated; and inputting the deviation value into an incremental PID control model to obtain the load change rate of the open system.

S32: and obtaining the load input amount of the open system according to the load change rate and the preset load amount, so that the open system absorbs the negative power generated by the closed system according to the load input amount.

It will be appreciated that after the rate of change of load for an open system is obtained, according to the formula: and B-last _ B + V-cycle can obtain the increment of the load, wherein B is the current input amount of the load, last _ B is the last input amount of the load, V is the load change rate, cycle is time, and the current input amount of the load and the preset load amount are summed to obtain the load input amount of the open system.

This embodiment is through being regarded as the input with the deviation value of actual load rate and predetermineeing the load rate, through the output load rate of change of incremental PID control model regulation, and then confirms the load input, has the control accuracy, efficient characteristics.

Referring to fig. 8, fig. 8 is a functional block diagram of an embodiment of the negative power control system for a crane according to the present invention.

In this embodiment, the negative power control system for a crane includes:

an engine 10; an open system 20; at least one closed system 30; and the negative power control apparatus 40 for the crane described in the above embodiment.

Wherein at least one of the closed system 30, the engine 10 and the open system 20 are in communication with the negative power control device 40.

It should be understood that, when at least one closed system 30 refers to two closed systems and only two closed systems are adopted to perform combined actions, when only one closed system weight descends to generate negative power, the other closed system and the weight consume the negative power, and the negative power control device 40 for the crane absorbs the residual negative power by adjusting the load input amount in the open system 20; when both the weights of the closed system are lowered to generate negative power, the negative power control apparatus 40 for the crane absorbs all the negative power by adjusting the amount of load input in the open system 20.

Under the working condition that at least one closed system 30 is three closed systems and three closed systems are adopted to perform combined action, when only one closed system or two closed systems of heavy objects descend to generate negative power, other closed systems and heavy objects consume the negative power, and the negative power control equipment 40 for the crane absorbs the residual negative power by adjusting the load input amount in the open system 20; when the weights of the three closed systems all descend to generate negative power, the negative power control apparatus 40 for the crane absorbs all the negative power by adjusting the amount of load input in the open system 20.

Further, referring to fig. 9, the negative power control system for a crane further includes a luffing mechanism 50, a negative power control device 40, and is further configured to determine a load input of the open system 20 when at least one of the closed system 30 and the luffing mechanism 50 are simultaneously actuated.

It should be understood that when at least one closed system 30 is referred to as a closed system and a closed system is used in a combined-action luffing mechanism, the luffing mechanism 50 consumes negative power when the closed system weight is lowered to produce negative power, and the negative power control device 40 for the crane absorbs the remaining negative power by adjusting the amount of load input in the open system 20.

When at least one closed system 30 is two closed systems and one luffing mechanism is adopted to perform combined action, a heavy object of one closed system generates negative power when descending, the luffing mechanism 50 consumes the negative power, the other closed system may consume the negative power and also may generate the negative power, and the negative power control device 40 for the crane absorbs the residual negative power by adjusting the load input amount in the open system 20.

The specific embodiment of the negative power control system for the crane of the present invention is basically the same as the embodiments of the control method described above, and is not described herein again.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium (e.g., ROM/RAM, magnetic disk, optical disk) as described above and includes instructions for enabling a terminal device (e.g., a mobile phone, a computer, a server, an air conditioner, or a network device) to execute the method according to the embodiments of the present invention.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.