CN116101904A - Control method and control device for hoisting equipment and hoisting equipment - Google Patents

Abstract

The invention relates to the field of engineering machinery, and discloses a control method and a control device for hoisting equipment, wherein the hoisting equipment comprises a driving mechanism and an executing mechanism, and the control method comprises the following steps: acquiring a preset position and an actual position of an executing mechanism; performing forward movement processing on the preset position to obtain a desired position; feedback control is carried out on deviation between the expected position and the actual position so as to obtain feedback frequency; and controlling the driving mechanism to work according to the feedback frequency so as to drive the actuating mechanism to act. By adopting the scheme of the invention, the control error can be reduced.

Description

Control method and control device for hoisting equipment and hoisting equipment

Technical Field

The invention relates to the field of engineering machinery, in particular to a control method and a control device for hoisting equipment and the hoisting equipment.

Background

Lifting-type equipment (e.g., a tower crane) is one of the most commonly used lifting equipment on construction sites for handling various construction raw materials such as concrete, rebar, forms, steel pipes, and the like. At present, hoisting equipment is mainly controlled by a driver in a high-altitude cab on a tower, so that the requirements on the proficiency of the driver, the control precision and the like are high, the labor cost is high, and the safety risk of high-altitude operation is high.

With the development of automatic driving technology, unmanned hoisting equipment is proposed by combining with the actual demand. The unmanned hoisting equipment can automatically plan the path, automatically complete the hoisting operation of the hoisting equipment, liberate manpower and solve some problems existing in the current construction of the hoisting equipment. The automatic operation control technology of the hoisting equipment is one of key technologies for realizing automatic hoisting operation of unmanned hoisting equipment, and the existing automatic operation control technology of the hoisting equipment usually adopts PID feedback control, so that the problem of larger control error in the prior art exists due to larger inertia of the hoisting equipment.

Disclosure of Invention

The invention aims to provide a control method, a control device, a processor and hoisting equipment for the hoisting equipment, so as to solve the problem of larger control error in the existing control method for the hoisting equipment.

In order to achieve the above object, a first aspect of the present invention provides a control method for a hoisting device, the hoisting device including a driving mechanism and an executing mechanism, the control method comprising:

acquiring a preset position and an actual position of an executing mechanism;

Performing forward movement processing on the preset position to obtain a desired position;

feedback control is carried out on deviation between the expected position and the actual position so as to obtain feedback frequency;

and controlling the driving mechanism to work according to the feedback frequency so as to drive the actuating mechanism to act.

In the embodiment of the invention, the preset position comprises a preset position sequence, and the expected position comprises an expected position sequence; advancing the preset position to obtain a desired position, including: and removing the first preset number of position values in the preset position sequence to obtain a desired position sequence.

In the embodiment of the invention, the preset position comprises a preset position sequence, and the expected position comprises an expected position sequence; advancing the preset position to obtain a desired position, including: selecting position values from the preset position sequences every second preset number to obtain a desired position sequence.

In the embodiment of the invention, the control method further comprises the following steps: and performing feedforward control on the preset position to obtain feedforward frequency.

In an embodiment of the present invention, performing feedforward control on a preset position to obtain a feedforward frequency includes: carrying out feedforward speed calculation on a preset position to obtain feedforward speed; and determining the product of the feedforward speed and a preset feedforward coefficient to obtain a feedforward frequency.

In an embodiment of the present invention, controlling the operation of the driving mechanism according to the feedback frequency includes: and controlling the driving mechanism to work according to the feedback frequency and the feedforward frequency.

In an embodiment of the present invention, controlling the operation of the driving mechanism according to the feedback frequency and the feedforward frequency includes: and controlling the driving mechanism to work according to the addition value of the feedback frequency and the feedforward frequency.

In an embodiment of the present invention, controlling the operation of the driving mechanism according to the added value of the feedback frequency and the feedforward frequency includes: and controlling the driving mechanism to work according to the added value and the preset compensation value.

In an embodiment of the invention, the drive mechanism includes a positive dead zone value; controlling the driving mechanism to work according to the added value and a preset compensation value, comprising: under the condition that the hoisting equipment is in a stop stage, determining the sum of the addition value and a preset compensation value; and controlling the driving mechanism to work according to the sum of the added value and the preset compensation value under the condition that the sum of the added value and the preset compensation value is smaller than the positive dead zone value.

In an embodiment of the invention, the drive mechanism includes a negative dead band value; controlling the driving mechanism to work according to the added value and a preset compensation value, comprising: under the condition that the hoisting equipment is in a stop stage, determining the difference between the addition value and a preset compensation value; and controlling the driving mechanism to work according to the difference between the added value and the preset compensation value under the condition that the difference between the added value and the preset compensation value is larger than the negative dead zone value.

In the embodiment of the present invention, feedback control is performed on the deviation between the expected position and the actual position to obtain the feedback frequency, including: and determining the feedback frequency according to the deviation, the preset proportional coefficient, the preset integral coefficient and the preset differential coefficient.

In the embodiment of the present invention, feedback control is performed on the deviation between the expected position and the actual position to obtain the feedback frequency, including: and determining the product value of the deviation and a preset proportionality coefficient to obtain the feedback frequency.

A second aspect of the invention provides a processor configured to perform a control method for a lifting-type device according to the above.

A third aspect of the present invention provides a control device for hoisting equipment, comprising: the position detection device is used for detecting the actual position of the actuating mechanism; and a processor according to the above.

A fourth aspect of the present invention provides a lifting device, comprising: an actuator; the driving mechanism is used for driving the executing mechanism to work; and the control device for hoisting equipment.

According to the technical scheme, the preset position and the actual position of the actuating mechanism are obtained, the preset position is subjected to forward movement processing to obtain the expected position, and further feedback control is performed on deviation between the expected position and the actual position, so that feedback frequency is obtained, and further the driving mechanism is controlled to work according to the feedback frequency, so that the actuating mechanism is driven to act. According to the scheme, the preset position is subjected to forward movement processing, so that an effective control instruction about the driving mechanism can be sent out in advance, and advanced acceleration or deceleration is realized, so that the problem of large control error of hoisting equipment caused by large inertia can be solved, feedback control is performed on deviation between the expected position and the actual position, position deviation can be regulated, and the position control precision of the actuating mechanism is improved.

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

Drawings

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

FIG. 1 schematically illustrates a flow chart of a control method for a lifting device in accordance with an embodiment of the present invention;

FIG. 2 schematically illustrates a control flow diagram of a control method for a lifting device according to an embodiment of the present invention;

fig. 3 schematically shows a block diagram of a control device for a lifting device according to an embodiment of the invention.

Detailed Description

The following describes specific embodiments of the present invention in detail with reference to the drawings. It should be understood that the detailed description and specific examples, while indicating and illustrating the invention, are not intended to limit the invention.

The existing control method mainly comprises three control methods of PID feedback control, feedforward control and a combined control method of the PID feedback control and the feedforward control: 1. the PID feedback control method is characterized in that the error between the input and the feedback of the system and the PID coefficient are calculated, and the calculated result is directly output to the execution unit, so that the method is easy to realize engineering, but the adjusting effect is behind the interference, the adjusting lag and the response are not timely, so that the control output value is unstable, and the method is difficult to be suitable for controlling the nonlinear, large inertia and large hysteresis control system of hoisting equipment; 2. the feedforward control method directly acts on output by utilizing input quantity, so that an open loop control method has the advantages of quick response, no need of detecting the output quantity of the system, but easy overcompensation or undercompensation and larger error; 3. the feedforward and PID feedback control method integrates the advantages of the feedforward and PID feedback control method, has the characteristics of quick response, small error and the like, but has poor stability and large error when being applied to a hoisting equipment control system such as nonlinearity, large inertia and large hysteresis.

The lifting device has the characteristics of large inertia, slow response, large action delay of the lifting device compared with an instruction, dead zone of the frequency converter and the like, the lifting hook and the lifting device body are flexibly connected through the steel wire rope, and the lifting hook can generate large swing due to sudden acceleration, deceleration or steering, wherein the swing is particularly obvious when the swing and amplitude changing mechanism are controlled, and the safety risk of collision between a lifting object and surrounding obstacles is increased by the large swing.

When the traditional hoisting equipment works, a driver sends an instruction to the frequency converter through the handle, and the frequency converter drives three mechanisms of rotation, amplitude variation and lifting to act so as to achieve the purpose of controlling the movement of the lifting hook, so that when the hoisting equipment operates automatically, the automatic control of the lifting hook can be completed by only sending the instruction to the frequency converter and controlling the three mechanisms to act. The automatic operation of the hoisting equipment is mainly divided into three stages of starting, stable operation and stopping. The start stage speed slowly rises from zero to a certain speed v, the steady operation stage is operated at the speed v, and the stop stage speed slowly falls from the speed v to zero.

Fig. 1 schematically shows a flow chart of a control method for a lifting device according to an embodiment of the invention. As shown in fig. 1, in an embodiment of the present invention, a control method for a lifting device is provided, and an example of application of the method to a processor of the lifting device is described, where the lifting device includes a driving mechanism and an executing mechanism, the control method may include the following steps:

Step S102, obtaining a preset position and an actual position of an executing mechanism.

It will be appreciated that the preset position is the desired position of the preset actuator. The actual position is the actual position of the actuator, and can be detected by a position detection device. The actuating mechanism can comprise, but is not limited to, a motor, a swing mechanism, a luffing structure, a lifting mechanism and a lifting hook, wherein the swing mechanism, the luffing structure and the lifting mechanism can drive the lifting hook to move through a lifting rope.

Specifically, the processor may acquire the preset position and the actual position of the actuator in real time or at preset time intervals.

Step S104, performing forward movement processing on the preset position to obtain a desired position.

It will be appreciated that the desired position is a new position of the actuator after the advance of the preset position.

Specifically, the processor may perform the forward movement processing on the preset position, so as to obtain a desired position, where the desired position is advanced compared with the preset position, so as to issue an effective control instruction (a control instruction value is greater than a dead zone value of the driving mechanism) related to the driving mechanism in advance, and further drive the actuating mechanism to work in advance.

In one embodiment, the advancing of the preset position may be achieved by: and inputting the preset position to an acceleration and deceleration controller. It can be understood that the input of the acceleration and deceleration controller is a preset position, and the output is a desired position, wherein the acceleration and deceleration controller can be a specific hardware device or a specific software algorithm.

Specifically, the processor inputs the preset position to the acceleration and deceleration controller, and the acceleration and deceleration controller processes the preset position and outputs the expected position, so that the processor obtains the expected position processed by the acceleration and deceleration controller.

Step S106, feedback control is carried out on the deviation between the expected position and the actual position so as to obtain the feedback frequency.

Specifically, the processor may determine a deviation value between the desired position and the actual position after obtaining the desired position and the actual position, and perform feedback control on the deviation value, so as to obtain a feedback frequency, where an algorithm of the feedback control may be a PID control algorithm, for example.

In one embodiment, feedback control of the deviation between the desired position and the actual position may be achieved by: the deviation between the desired position and the actual position is input to a feedback controller. It can be understood that the feedback controller is mainly used for adjusting the position deviation, the input of the feedback controller is the deviation value between the expected position and the actual position, and the output is the feedback frequency. The feedback controller may be a specific hardware device or a specific software algorithm.

Specifically, the processor may determine a deviation value between the desired position and the actual position after obtaining the desired position and the actual position, and use the deviation value as an input of the feedback controller, thereby obtaining a feedback frequency output by the feedback controller.

Step S108, the driving mechanism is controlled to work according to the feedback frequency so as to drive the executing mechanism to act.

It will be appreciated that the drive mechanism is configured to receive instructions or data from the processor or controller to actuate the actuator, wherein the drive mechanism may include, but is not limited to, a frequency converter.

Specifically, the processor may control the operation of the driving mechanism (e.g., a frequency converter) according to the feedback frequency, thereby driving the actuation mechanism (e.g., a slewing mechanism) to act.

According to the control method for the hoisting equipment, the preset position and the actual position of the actuating mechanism are obtained, the preset position is advanced to obtain the expected position, and further feedback control is performed on deviation between the expected position and the actual position, so that the feedback frequency is obtained, and further the actuating mechanism is controlled to work according to the feedback frequency, so that the actuating mechanism is driven to act. According to the control method, the preset position is subjected to forward movement processing, so that an effective control instruction related to the driving mechanism can be sent out in advance, and advanced acceleration or deceleration is realized, so that the problem of large control error of hoisting equipment caused by large inertia can be solved, feedback control is performed on deviation between the expected position and the actual position, position deviation can be adjusted, and the position control precision of the actuating mechanism is improved.

In one embodiment, the preset locations comprise a sequence of preset locations, and the desired locations comprise a sequence of desired locations; advancing the preset position to obtain a desired position, including: and removing the first preset number of position values in the preset position sequence to obtain a desired position sequence.

It will be appreciated that the sequence of preset positions, i.e. the sequence of positions of the trajectory plan or the original plan, comprises a plurality of preset positions, e.g. [ x (0), x (1) … x (n-1), x (n) ], wherein the plurality of preset positions may be arranged at a time interval, which may be e.g. 100ms. The desired position sequence is a sequence including a plurality of desired positions processed by the acceleration/deceleration controller, for example, [ x (N), x (n+1) … x (N-1), x (N) ], wherein the plurality of desired positions may be arranged at a certain time interval. The first preset number is the number of preset positions to be removed in the preset position sequence, and the selection principle of the first preset number is to ensure that the difference between the expected position and the actual position is as large as possible on the premise that the actual position of an actuating mechanism (for example, a lifting hook) does not advance the expected position, so that an effective control instruction is sent in advance.

Specifically, the processor may move the preset position sequence (i.e. the position sequence of the trajectory planning) forward by a first preset amount (e.g. N) of position data, i.e. remove a position value of the preset position sequence located in front of the first preset amount (e.g. N), i.e. remove a position value of a section of the preset position sequence located in front of the preset position sequence x (N), i.e. a position value of the preset position sequence from x (0) to x (N-1), so as to obtain a desired position sequence (i.e. a new position sequence), e.g. x (N), x (n+1) … x (N-1), x (N), and take the desired position sequence as an input of the feedback controller, and the position difference e (N) between the desired position sequence and the actual actuator becomes larger than the originally planned position sequence, and the control command value becomes larger accordingly, so as to issue an effective command (the control command value is larger than the value of the driving mechanism) in advance, thereby realizing acceleration or deceleration in advance, and solving the problem caused by the control of the hoisting equipment with large inertia. Further, the first preset number (i.e. the parameter N) is selected according to a principle of ensuring that the actual position (e.g. the actual turning position) does not lead the position (e.g. the turning position) of the track planning, so that the position difference e (N) is as large as possible, and an effective control command is issued in advance.

In one embodiment, the preset locations comprise a sequence of preset locations, and the desired locations comprise a sequence of desired locations; advancing the preset position to obtain a desired position, including: selecting position values from the preset position sequences every second preset number to obtain a desired position sequence.

It will be appreciated that the second preset number is a preset number, e.g. 2 or 5, of interval data selections.

Specifically, for the position sequence of the track planning, the processor may take a position value from a second preset number (for example, M) of data at each interval, so as to obtain a desired position sequence, and may increase the error e, so as to achieve the purpose of issuing the effective command in advance.

In one embodiment, the control method may further include: and performing feedforward control on the preset position to obtain feedforward frequency.

It can be understood that the lifting hook is flexibly connected with the lifting type equipment body through a steel wire rope, and sudden acceleration, deceleration or steering can cause the lifting hook to swing greatly. The feedforward control can ensure the stable operation of hoisting equipment and avoid abrupt acceleration, acceleration or steering.

Specifically, the processor may perform feedforward control on the preset position, so as to obtain a feedforward frequency.

In one embodiment, feedforward control is performed on a preset position to obtain a feedforward frequency, including: carrying out feedforward speed calculation on a preset position to obtain feedforward speed; and determining the product of the feedforward speed and a preset feedforward coefficient to obtain a feedforward frequency.

Specifically, in a steady operation stage of the hoisting equipment, the executing mechanism operates at a certain speed v, and in order to avoid sudden acceleration and deceleration, the processor calculates a feedforward average speed v (n) according to a preset position with a preset time interval (for example, 100 ms) as a period, and multiplies v (n) by a feedforward coefficient Kf to obtain a feedforward frequency q (n).

v(n)＝(x(n)-x(n-m))/(m×0.1)

q(n)＝v(n)×Kf

Wherein x (n), x (n-m) are preset positions of the executing mechanism, m is a third preset number, and can be preset, the feedforward coefficient Kf is measured through experiments, namely, a determined control command C is sent to the executing mechanism, positions are acquired in real time in a fixed period T, and the speed V0 under the control command is calculated through the positions and the time T, so kf=c/V0.

In one embodiment, feedforward control of the preset position may be achieved by: the preset position is input to the speed feedforward controller. It can be understood that the speed feedforward controller is used for ensuring the stable operation of the hoisting equipment, avoiding abrupt acceleration, acceleration or steering, and the input of the speed feedforward controller is a preset position and the output is feedforward frequency. The speed feedforward controller can be a specific hardware device or a specific software algorithm.

Specifically, the processor inputs a preset position to the speed feedforward controller, and the speed feedforward controller outputs feedforward frequency after processing the preset position.

In one embodiment, controlling operation of the drive mechanism according to the feedback frequency includes: and controlling the driving mechanism to work according to the feedback frequency and the feedforward frequency.

Specifically, the processor may control the operation of the driving mechanism according to both the feedback frequency and the feedforward frequency, thereby driving the actuator to act.

In one embodiment, controlling operation of the drive mechanism based on the feedback frequency and the feedforward frequency includes: and controlling the driving mechanism to work according to the addition value of the feedback frequency and the feedforward frequency.

Specifically, the processor may add the feedback frequency and the feedforward frequency, so as to control the driving mechanism to work according to the added value of the feedback frequency and the feedforward frequency, thereby driving the actuator to act.

In one embodiment, controlling operation of the drive mechanism based on the sum of the feedback frequency and the feedforward frequency includes: and controlling the driving mechanism to work according to the added value and the preset compensation value.

It will be appreciated that since the dead zone exists in the drive mechanism (e.g. frequency converter), the condition for the final stopping of the hoisting device is that the command value of the transmitted drive mechanism is smaller than the dead zone value of the drive mechanism, and the feedback control plays a major role in the stopping phase of the hoisting device (e.g. tower crane), the condition for the stopping of the hoisting device is that the feedback frequency is smaller than the dead zone value of the drive mechanism, wherein the feedback frequency consists of an error and a preset feedback control parameter, and the error may not meet the desired final error (e.g. 0.05 degrees), and thus, the preset compensation value is set for improving the control accuracy. Regarding the preset compensation value, the reasonable compensation value can be obtained through experiments by combining the condition of the starting stage of the hoisting equipment, the speed of the hoisting equipment in the starting stage is very low, and the overcompensation can be caused by the excessive value, so that the control stability of the hoisting equipment is affected.

Specifically, the processor can control the driving mechanism to work according to the added value of the feedback frequency and the feedforward frequency and the preset compensation value, so that the final position control precision is improved.

In one embodiment, controlling the driving mechanism to work according to the added value of the feedback frequency and the feedforward frequency and the preset compensation value can be achieved by the following ways: the sum of the feedback frequency and the feedforward frequency and a preset compensation value are input into a dead zone compensator, and it can be understood that the dead zone compensator is used for reducing the position error, and the input is the sum of the feedback frequency and the feedforward frequency and the preset compensation value, and the output is a control command value of the driving mechanism. The dead zone compensator may be a specific hardware device or a specific software algorithm.

In one embodiment, the drive mechanism includes a positive dead band value; controlling the driving mechanism to work according to the added value and a preset compensation value, comprising: under the condition that the hoisting equipment is in a stop stage, determining the sum of the addition value and a preset compensation value; and controlling the driving mechanism to work according to the sum of the added value and the preset compensation value under the condition that the sum of the added value and the preset compensation value is smaller than the positive dead zone value.

It can be appreciated that since the actuators (e.g., slewing, luffing and lifting actuators) of the lifting type device can move forward, the driving mechanism (frequency converter) has a forward dead zone, and the magnitude of the position error can be reduced by presetting the compensation value.

Specifically, in the stopping stage of the hoisting device, the processor determines the sum of the added value of the feedforward frequency and the feedback frequency and the preset compensation value, namely, performs addition calculation on the added value and the preset compensation value, and because the feedforward frequency is approximately 0 in this stage, the influence of the feedforward frequency can be temporarily not considered, and when the sum of the added value of the feedforward frequency and the feedback frequency and the preset compensation value is smaller than the positive dead zone value, the driving mechanism can be controlled to work according to the sum of the added value and the preset compensation value (approximately equal to the sum of the feedback frequency and the preset compensation value).

In one embodiment, the frequency converter includes a negative dead band value; controlling the driving mechanism to work according to the added value and a preset compensation value, comprising: under the condition that the hoisting equipment is in a stop stage, determining the difference between the addition value and a preset compensation value; and controlling the driving mechanism to work according to the difference between the added value and the preset compensation value under the condition that the difference between the added value and the preset compensation value is larger than the negative dead zone value.

It will be appreciated that since the actuators (e.g., slewing, luffing and lifting actuators) of the lifting-type apparatus are reversibly movable, the drive mechanism (transducer) has a reverse dead zone, and the magnitude of the position error can be reduced by presetting the compensation value.

Specifically, in the suspension type equipment stopping stage, the processor determines the difference between the addition value of the feedforward frequency and the feedback frequency and the preset compensation value, that is, the subtraction calculation is performed on the addition value and the preset compensation value, and because the feedforward frequency is approximately 0 in this stage, the influence of the feedforward frequency can be temporarily not considered, and when the difference between the addition value of the feedforward frequency and the feedback frequency and the preset compensation value is greater than the negative dead zone value, the driving mechanism can be controlled to work according to the difference between the addition value and the preset compensation value (approximately equal to the difference between the feedback frequency and the preset compensation value).

In one embodiment, feedback controlling the deviation between the desired position and the actual position to obtain the feedback frequency includes: and determining the feedback frequency according to the deviation, the preset proportional coefficient, the preset integral coefficient and the preset differential coefficient.

Specifically, when the feedback control employs a PID control algorithm, the processor may determine the feedback frequency based on a deviation between the actual position and the desired position and a pre-stored preset proportional coefficient, preset integral coefficient, and preset derivative coefficient.

In one embodiment, feedback controlling the deviation between the desired position and the actual position includes: and determining the product value of the deviation and a preset proportionality coefficient to obtain the feedback frequency.

Specifically, the processor may multiply the deviation of the desired position and the actual position by a preset scaling factor, thereby obtaining the feedback frequency.

The feedback control is illustrated by taking PID control as an example, the PID coefficients include a proportional coefficient Kp, an integral coefficient Ki and a differential coefficient Kd, specific numerical values can be obtained by adopting a classical adjusting method of PID, in order to simplify the PID coefficient adjustment, ki=0 and kd=0 can be achieved here, only Kp needs to be adjusted, and the PID calculation formula can be simplified as follows:

y(n)＝Kp×e(n)

further, the PID control (feedback control) mainly prevents overcompensation or undercompensation of the speed feedforward control in the steady operation stage, adjusts the position deviation in the later stage of the stopping stage, and improves the final position control precision in the stopping stage.

Fig. 2 schematically illustrates a control flow diagram of a control method for a lifting device according to an embodiment of the invention. As shown in fig. 2, the hoisting equipment is illustrated by taking a tower crane as an example, the tower crane comprises a driving mechanism (such as a frequency converter) and an executing mechanism, the executing mechanism comprises three large mechanisms including a rotation mechanism, a luffing mechanism and a lifting mechanism, the three large mechanisms can drive a lifting hook to act through a lifting rope, the track planning of the lifting hook carries out track planning according to three stages of starting, stable running and stopping, and the position sequence of the planned rotation mechanism, luffing mechanism and lifting mechanism is a position sequence taking 100ms as a time interval, so that the position sequence is ideal. The control methods of the rotation, amplitude variation and lifting mechanism are consistent, and the technical scheme is described by taking the rotation mechanism as an example only. As shown in fig. 2, the control method for the hoisting equipment in the application includes four parts of an acceleration and deceleration controller, a speed feedforward controller, a PID position controller and a dead zone compensator of a frequency converter, a revolving (and/or amplitude and/or lifting) position sequence of track planning (i.e. x (n) in fig. 2) is used as input of the acceleration and deceleration controller and the speed feedforward controller, after the acceleration and deceleration controller processes the input sequence, the output of the acceleration and deceleration controller subtracts the actual revolving (and/or amplitude and/or lifting) position value of the hoisting equipment to obtain a difference e (n), the PID position controller takes e (n) as input, performs PID operation, adds the output y (n) of the PID position controller and the output q (n) of the speed feedforward controller to obtain a result u (n), and the dead zone compensator of the frequency converter takes u (n) as input, obtains a final control instruction o (n) after compensation processing, and outputs the final control instruction o (n) to the revolving frequency converter.

In the starting and stopping stages, the speed value is very small, the position error is also very small, the value of the control command is also small, because the frequency converter has a dead zone, the executing mechanism executes the command to start to act only when the control command value is larger than the dead zone value, and the inertia of the hoisting equipment is large, so that the starting and stopping actions are slow, the action of the hoisting equipment is delayed more than the command, larger control error is generated, and even the system is unstable.

Therefore, the control method provides an acceleration and deceleration controller, and an effective control instruction is sent out in advance. The position sequence [ x (0), x (1) … x (N-1), x (N) ] of the track planning is moved forward by N position data to obtain a new position sequence [ x (N), x (n+1) … x (N-1), x (N) ], the sequence is used as one input of the PID position controller, the position difference e (N) between the position sequence and the actual executing mechanism becomes larger relative to the originally planned position sequence, the control instruction also becomes larger, and therefore an effective instruction (the control instruction value is larger than the dead zone value of the frequency converter) is sent in advance, the advanced acceleration and the deceleration are realized, and the control difficulty caused by large inertia of hoisting equipment is solved. The selection principle of the parameter N is as follows: on the premise of ensuring that the actual rotation position does not lead the rotation position of the track planning, the position difference e (n) is as large as possible, so that an effective control instruction is sent in advance.

The lifting hook is flexibly connected with the lifting device body through a steel wire rope, and the lifting hook can swing greatly due to sudden acceleration, deceleration or steering. The stable operation stage of the hoisting equipment mainly ensures the stable operation of the hoisting equipment and avoids abrupt acceleration, deceleration or steering, and the speed feedforward controller plays a main role in the stage.

In a stable operation stage, the hoisting equipment operates at a certain speed v so as to avoid abrupt acceleration and deceleration, the speed feedforward controller takes a position sequence of track planning as input, calculates feedforward average speed v (n) by taking 100ms as a period, and multiplies v (n) by feedforward coefficient Kf to obtain output q (n) of the speed feedforward controller.

v(n)＝(x(n)-x(n-m))/(m×0.1)

q(n)＝v(n)×Kf

The feedforward coefficient Kf is measured through experiments, namely a determined control command C is sent to an executing mechanism, the rotation position is collected in real time in a fixed period T, and the speed V0 under the control command is calculated through the position and the time T, so kf=C/V0.

The PID position controller takes a new position sequence output by the acceleration and deceleration controller and a revolving actual position difference e (n) as inputs, and obtains PID position control output y (n) through PID calculation.

Kp, ki and Kd in the PID coefficient can be obtained by adopting a classical PID regulating method, so that Ki=0 and Kd=0 are realized in order to simplify PID coefficient regulation, only Kp is required to be regulated, and a PID calculation formula is simplified into:

y(n)＝Kp×e(n)

The PID position controller mainly prevents overcompensation or undercompensation of speed feedforward control in a stable operation stage, adjusts position deviation in the later stage of a stopping stage, and improves final position control precision in the stopping stage.

Since the frequency converter has dead zone, the condition that the hoisting equipment stops moving finally is that the command value of the frequency converter is smaller than the dead zone value of the frequency converter, and the PID controller plays a main role in the stopping stage of the hoisting equipment, therefore, the condition that the hoisting equipment stops moving is Kp×e1< D, wherein e1 is the final error expected by the rotation, and the error e1=D/Kp, e1 may not meet the final error (such as 0.05 degree) expected at the moment. In order to improve the control precision, a dead zone compensator of a frequency converter is added, in order to meet the condition that the hoisting equipment stops moving (the command value of the frequency converter is smaller than the dead zone value of the frequency converter), the compensation value C is required to meet the condition that C+e1×Kp < D, the larger the C value is, the smaller the error e1 value is, of course, the compensation value C is required to be combined with the condition of the starting stage of the hoisting equipment, a reasonable compensation value is obtained through experiments, the speed of the hoisting equipment is very small in the starting stage, and the excessive C value can cause overcompensation to influence the control stability of the hoisting equipment. The rotation, amplitude variation and lifting executing mechanism of the hoisting equipment can move in the forward and reverse directions, so that the frequency converter has a forward and reverse bidirectional dead zone, the control instruction is added with the compensation value C when the control instruction value is larger than e1×Kp, and the control instruction is subtracted with the compensation value C when the control instruction value is smaller than-e1×Kp.

Test verification of the control method for the hoisting equipment in the embodiment of the application on the hoisting equipment shows that the track tracking error (the difference between the position of track planning and the position of the actual motion of the lifting hook of the hoisting equipment at the same time) is smaller, for example, the error is smaller than 0.8 m, and the stability of the motion of the lifting hook is better than that of manual operation; the test result of the feedforward and feedback control method on the hoisting equipment shows that the error is larger, for example, the error is 5 meters, which is far larger than the error of the technical scheme, and the stability is also poor.

In summary, the control method for the hoisting equipment in the embodiment of the application comprises four parts of an acceleration and deceleration controller, a speed feedforward controller, a PID (proportion integration differentiation) position controller and a frequency converter dead zone compensator, wherein an effective instruction is sent out in advance through the acceleration and deceleration controller, so that the problem of large control error of the hoisting equipment due to large inertia is solved, the stable operation of the hoisting equipment can be ensured through the speed feedforward controller, abrupt acceleration and deceleration or steering is avoided, the feedback controller can prevent speed feedforward control from overcompensation or undercompensation, position deviation is regulated, position control precision is improved, the frequency converter dead zone compensator and the PID position controller jointly act, final position control precision in a stopping stage is improved, and the technical scheme solves the problems of stable and accurate control of large inertia and large hysteresis systems such as a tower crane, and has the advantages of small error, stable control and the like.

Embodiments of the present invention provide a processor configured to: acquiring a preset position and an actual position of an executing mechanism; performing forward movement processing on the preset position to obtain a desired position; feedback control is carried out on deviation between the expected position and the actual position so as to obtain feedback frequency; and controlling the driving mechanism to work according to the feedback frequency so as to drive the actuating mechanism to act.

According to the technical scheme, the preset position and the actual position of the actuating mechanism are obtained, the preset position is subjected to forward movement processing to obtain the expected position, and further feedback control is performed on deviation between the expected position and the actual position, so that feedback frequency is obtained, and further the driving mechanism is controlled to work according to the feedback frequency, so that the actuating mechanism is driven to act. According to the control method, the preset position is subjected to forward movement processing, so that an effective control instruction related to the driving mechanism can be sent out in advance, and advanced acceleration or deceleration is realized, so that the problem of large control error of hoisting equipment caused by large inertia can be solved, feedback control is performed on deviation between the expected position and the actual position, position deviation can be adjusted, and the position control precision of the actuating mechanism is improved.

In one embodiment, the preset locations comprise a sequence of preset locations, and the desired locations comprise a sequence of desired locations; the processor is further configured to: and removing the first preset number of position values in the preset position sequence to obtain a desired position sequence.

In one embodiment, the preset locations comprise a sequence of preset locations, and the desired locations comprise a sequence of desired locations; the processor is further configured to: selecting position values from the preset position sequences every second preset number to obtain a desired position sequence.

In one embodiment, the processor is further configured to: and performing feedforward control on the preset position to obtain feedforward frequency.

In one embodiment, the processor is further configured to: carrying out feedforward speed calculation on a preset position to obtain feedforward speed; and determining the product of the feedforward speed and a preset feedforward coefficient to obtain a feedforward frequency.

In one embodiment, the processor is further configured to: and controlling the driving mechanism to work according to the feedback frequency and the feedforward frequency.

In one embodiment, the processor is further configured to: and controlling the driving mechanism to work according to the addition value of the feedback frequency and the feedforward frequency.

In one embodiment, the processor is further configured to: and controlling the driving mechanism to work according to the added value and the preset compensation value.

In one embodiment, the drive mechanism includes a positive dead band value; the processor is further configured to: under the condition that the hoisting equipment is in a stop stage, determining the sum of the addition value and a preset compensation value; and controlling the driving mechanism to work according to the sum of the added value and the preset compensation value under the condition that the sum of the added value and the preset compensation value is smaller than the positive dead zone value.

In one embodiment, the drive mechanism includes a negative dead band value; the processor is further configured to: under the condition that the hoisting equipment is in a stop stage, determining the difference between the addition value and a preset compensation value; and controlling the driving mechanism to work according to the difference between the added value and the preset compensation value under the condition that the difference between the added value and the preset compensation value is larger than the negative dead zone value.

In one embodiment, the processor is further configured to: and determining the feedback frequency according to the deviation, the preset proportional coefficient, the preset integral coefficient and the preset differential coefficient.

In one embodiment, the processor is further configured to: and determining the product value of the deviation and a preset proportionality coefficient to obtain the feedback frequency.

In one embodiment, as shown in fig. 2, the processor may include four unit modules of an acceleration and deceleration controller, a speed feedforward controller, a PID position controller and a dead zone compensator of the frequency converter, and further, the acceleration and deceleration controller, the speed feedforward controller, the PID position controller and the dead zone compensator of the frequency converter may be implemented in a hardware mode, a software algorithm mode or a mode combining the software algorithm and the hardware mode.

Fig. 3 schematically shows a block diagram of a control device for a lifting device according to an embodiment of the invention. As shown in fig. 3, in an embodiment of the present invention, there is provided a control apparatus 300 for a lifting device, the lifting device including a driving mechanism and an executing mechanism, the control apparatus 300 for a lifting device including a position detecting device 310 and a processor 320, wherein:

a position detection device 310 for detecting the actual position of the actuator.

A processor 320 configured to: acquiring a preset position and an actual position of an executing mechanism; performing forward movement processing on the preset position to obtain a desired position; feedback control is carried out on deviation between the expected position and the actual position so as to obtain feedback frequency; and controlling the driving mechanism to work according to the feedback frequency so as to drive the actuating mechanism to act.

According to the control device 300 for hoisting equipment, the preset position and the actual position of the actuating mechanism are obtained, the preset position is advanced to obtain the expected position, and further, the deviation between the expected position and the actual position is subjected to feedback control, so that the feedback frequency is obtained, and further, the actuating mechanism is controlled to work according to the feedback frequency, so that the actuating mechanism is driven to act. The control device can send out an effective control instruction related to the driving mechanism in advance by carrying out forward movement processing on the preset position, so that acceleration or deceleration in advance is realized, the problem of large control error of hoisting equipment caused by large inertia can be solved, feedback control is carried out on deviation between an expected position and an actual position, position deviation can be regulated, and the position control precision of the actuating mechanism is improved.

In one embodiment, the preset locations comprise a sequence of preset locations, and the desired locations comprise a sequence of desired locations; the processor 320 is further configured to: and removing the first preset number of position values in the preset position sequence to obtain a desired position sequence.

In one embodiment, the preset locations comprise a sequence of preset locations, and the desired locations comprise a sequence of desired locations; the processor 320 is further configured to: selecting position values from the preset position sequences every second preset number to obtain a desired position sequence. A step of

In one embodiment, the processor 320 is further configured to: and performing feedforward control on the preset position to obtain feedforward frequency.

In one embodiment, the processor 320 is further configured to: carrying out feedforward speed calculation on a preset position to obtain feedforward speed; and determining the product of the feedforward speed and a preset feedforward coefficient to obtain a feedforward frequency.

In one embodiment, the processor 320 is further configured to: and controlling the driving mechanism to work according to the feedback frequency and the feedforward frequency.

In one embodiment, the processor 320 is further configured to: and controlling the driving mechanism to work according to the addition value of the feedback frequency and the feedforward frequency.

In one embodiment, the processor 320 is further configured to: and controlling the driving mechanism to work according to the added value and the preset compensation value.

In one embodiment, the drive mechanism includes a positive dead band value; the processor 320 is further configured to: under the condition that the hoisting equipment is in a stop stage, determining the sum of the addition value and a preset compensation value; and controlling the driving mechanism to work according to the sum of the added value and the preset compensation value under the condition that the sum of the added value and the preset compensation value is smaller than the positive dead zone value.

In one embodiment, the drive mechanism includes a negative dead band value; the processor 320 is further configured to: under the condition that the hoisting equipment is in a stop stage, determining the difference between the addition value and a preset compensation value; and controlling the driving mechanism to work according to the difference between the added value and the preset compensation value under the condition that the difference between the added value and the preset compensation value is larger than the negative dead zone value.

In one embodiment, the processor 320 is further configured to: and determining the feedback frequency according to the deviation, the preset proportional coefficient, the preset integral coefficient and the preset differential coefficient.

In one embodiment, the processor 320 is further configured to: and determining the product value of the deviation and a preset proportionality coefficient to obtain the feedback frequency.

The embodiment of the invention provides hoisting equipment, which comprises: an actuator; the driving mechanism is used for driving the executing mechanism to work; and the control device for hoisting equipment in the embodiment.

Therefore, the technical scheme solves the problem of stable and accurate control of large inertia and large hysteresis systems of hoisting equipment, carries out carrying verification on the hoisting equipment, and has the advantages of small error, stable control and the like.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the scope of the technical concept of the present invention, and all the simple modifications belong to the protection scope of the present invention.

In addition, the specific features described in the above embodiments may be combined in any suitable manner without contradiction. The various possible combinations of the invention are not described in detail in order to avoid unnecessary repetition.

Moreover, any combination of the various embodiments of the invention can be made without departing from the spirit of the invention, which should also be considered as disclosed herein.

Claims (15)

1. A control method for a lifting device, the lifting device comprising a driving mechanism and an executing mechanism, the control method comprising:

acquiring a preset position and an actual position of the executing mechanism;

performing forward movement processing on the preset position to obtain a desired position;

performing feedback control on the deviation between the expected position and the actual position to obtain feedback frequency;

and controlling the driving mechanism to work according to the feedback frequency so as to drive the actuating mechanism to act.

2. The control method according to claim 1, wherein the preset position includes a preset position sequence, and the desired position includes a desired position sequence; the advancing processing is performed on the preset position to obtain a desired position, including:

and removing the position values of the first preset number in the preset position sequence to obtain the expected position sequence.

3. The control method according to claim 1, wherein the preset position includes a preset position sequence, and the desired position includes a desired position sequence; the advancing processing is performed on the preset position to obtain a desired position, including:

And selecting position values from the preset position sequences every second preset number to obtain the expected position sequences.

4. The control method according to claim 1, characterized in that the control method further comprises:

and performing feedforward control on the preset position to obtain feedforward frequency.

5. The control method according to claim 4, wherein the feedforward controlling the preset position to obtain a feedforward frequency includes:

performing feedforward speed calculation on the preset position to obtain feedforward speed;

and determining the product of the feedforward speed and a preset feedforward coefficient to obtain a feedforward frequency.

6. The control method of claim 5, wherein controlling operation of the drive mechanism in accordance with the feedback frequency comprises:

and controlling the driving mechanism to work according to the feedback frequency and the feedforward frequency.

7. The control method according to claim 6, wherein the controlling the driving mechanism to operate according to the feedback frequency and the feedforward frequency includes:

and controlling the driving mechanism to work according to the addition value of the feedback frequency and the feedforward frequency.

8. The control method according to claim 7, wherein the controlling the driving mechanism to operate according to the added value of the feedback frequency and the feedforward frequency includes:

and controlling the driving mechanism to work according to the added value and a preset compensation value.

9. The control method according to claim 8, characterized in that the driving mechanism includes a positive dead zone value; the controlling the driving mechanism to work according to the added value and the preset compensation value comprises the following steps:

determining the sum of the addition value and the preset compensation value under the condition that the hoisting equipment is in a stop stage;

and controlling the driving mechanism to work according to the sum of the added value and the preset compensation value under the condition that the sum of the added value and the preset compensation value is smaller than the positive dead zone value.

10. The control method according to claim 8, characterized in that the drive mechanism includes a negative dead zone value; the controlling the driving mechanism to work according to the added value and the preset compensation value comprises the following steps:

determining the difference between the added value and the preset compensation value under the condition that the hoisting equipment is in a stop stage;

and controlling the driving mechanism to work according to the difference between the added value and the preset compensation value under the condition that the difference between the added value and the preset compensation value is larger than the negative dead zone value.

11. The control method according to claim 1, characterized in that the feedback controlling of the deviation between the desired position and the actual position to obtain the feedback frequency includes:

and determining the feedback frequency according to the deviation, the preset proportional coefficient, the preset integral coefficient and the preset differential coefficient.

12. The control method according to claim 1, characterized in that the feedback controlling of the deviation between the desired position and the actual position to obtain the feedback frequency includes:

and determining a product value of the deviation and a preset proportionality coefficient to obtain the feedback frequency.

13. A processor, characterized by being configured to perform the control method for a lifting-type device according to any one of claims 1 to 12.

14. A control device for a lifting device, comprising:

the position detection device is used for detecting the actual position of the actuating mechanism; and

the processor of claim 13.

15. A lifting device, comprising:

an actuator;

the driving mechanism is used for driving the actuating mechanism to act; and

Control device for a lifting-type apparatus according to claim 14.

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