JP2017165539A - Control device of crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a crane which can avoid a collision with an obstacle by simultaneously performing a hoist motion and a traverse motion, and moving a suspended cargo along an arbitrary trajectory.SOLUTION: In a control device having a hoist device 60 for driving a hoist mechanism 12 by an electric motor 14, and a traverse device 50 for driving a traverse mechanism 11 by an electric motor 13, and moving a suspended cargo along an arbitrary moving trajectory by controlling the electric motors 13, 14, the control device comprises: trajectory creation means 24 for creating a moving trajectory; electric motor control means 17 for controlling rotation positions and speeds of the electric motor 13, 14 on the basis of the moving trajectory; load estimation means 28 for estimating a load of the suspended cargo from a state amount of the electric motor 14; and speed calculation means 32 for calculating operable maximum speed command values of the electric motors 13, 14 from the estimated load, mechanical loss torque and acceleration torque. The trajectory creation means 24 recalculates the moving trajectory on the basis of the operable maximum speed command value during an operation of a crane.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a crane control device including a hoisting device driven by an electric motor and a traversing device.

FIG. 6 shows a conventional crane control apparatus described in Patent Document 1. In FIG.
In FIG. 6, the speed command value conversion circuit 102 commands a speed command value N ^# for the induction motor 203 based on the output of the speed command device 101 or a speed calculation circuit 113 described later. The single integrator 103 increases or decreases until reaching the speed command value N ^# (N ^* = N ^# ) by a predetermined acceleration gradient (increase value / unit time) or deceleration gradient (decrease value / unit time). Outputs the speed set value N ^* .
The speed adjuster 104 outputs a torque command value τ ^* that makes the deviation between the speed set value N ^* and the speed detected value n by the speed detector 107 zero. The magnetic flux command value calculator 105 calculates and outputs a magnetic flux command value φ ^* from the speed detection value n.

The vector calculator 106 outputs a control signal for vector control of the inverter 202 from the torque command value τ ^* and the magnetic flux command value φ ^* . As a result, the power of the AC power supply 201 is converted into AC power having a desired voltage and frequency by the inverter 202 and supplied to the induction motor 203, and variable speed control of the motor 203 is performed.

FIG. 7 is a time chart showing the relationship between the speed command value N ^# and the speed set value N ^* .
7, when the speed command value N ^# of forward direction is issued at time T _0, the time T ₀ period through T _1, the speed setting value based on the acceleration gradient is set to a single integrator 103 N ^* increased in the forward direction, and ^N * = ^{N #} at time _{T 1.} Period from time _{T 1} to time _{T 2,} the speed command value ^{N #} is zero, a single integrator 103 outputs a ^N * (= ^{N #),} the period of time _T 2, through T ₃ are single integrator 103 reduces the forward direction of the value of the speed setpoint N ^* on the basis of the deceleration gradient is set to, the N ^{* =} 0 at time T _3.

From time _{T 3,} the period until the time _{T 4} the speed command value ^{N #} is a value in the reverse direction, a single integrator 103 outputs a ^N * (= 0), the period of time _T 4 through T ₅ is increases the value of the reverse rotation direction of the speed setpoint ^{N *} on the basis of the deceleration gradient, and ^N * = ^{N #} at time _{T 5.} Period from time _{T 5} to time _{T 6} to the speed command value ^{N #} becomes zero, a single integrator 103 outputs a ^N * (= ^{N #),} the period of time _T 6 through T ₇ are accelerated gradient reducing the value of the reverse rotation direction of the speed setpoint N ^* on the basis of, the N ^{* =} 0 at time T _7.

  FIG. 8 is an operation explanatory diagram of a system in which the hoisting machine 204b and the load m (whose weight is also assumed to be m) are driven as the load 204 of the induction motor 203 through the speed reducer by the control device shown in FIG. is there. FIG. 9 is an overall configuration diagram of the above system, and 204a indicates a reduction gear.

In FIG. 8, (a) shows the state of the hoisting machine, (b) shows the speed of the induction motor 203 that raises and lowers the hoisting machine, and (c) shows the output torque of the induction motor 203 that accompanies the raising and lowering of the hoisting machine. Yes.
Prior to time T ₀ , load m is on the ground. At this time, the induction motor 203 is stopped (speed = 0) and is braked by the brake. Hoist 204b starts winding from the time T _0, but the left end in FIG. 8 (a) is a state of the hoisting machine of the time T _0, after opening the brake, the period from time T ₀ through T ₁ The hoisting speed v of the hoisting machine 204b is increased with the acceleration gradient set in the single integrator 103.

At time _{T 1,} the speed command value ^{N #} and the speed setting value ^{N *} matches the period of time _T 1 through T ₂ is a winding speed v is constant. During the period from time T _{2 to} time T ₃ , the winding speed v is decreased with the deceleration gradient set in the single integrator 103. In the period from time T _{3 to} T ₄ , the induction motor 203 is stopped and is braked by the brake. During this period, as shown in the center of FIG. 8A, the load m is stopped in the air.

Next, during the period of time T _{4 to} T _5, the lowering speed v of the hoisting machine 204 b is increased with the deceleration gradient set in the single integrator 103. At time _{T 5,} the speed command value ^{N #} and the speed setting value ^{N *} matches the period of time _T 5 through T ₆ is lowering the speed v is constant.

During the period from time T _{6 to} T _7, the lowering speed v is decreased with the acceleration gradient set in the single integrator 103. In the time T ₇ after the period, load m is located on the ground. At this time, the induction motor 203 is stopped and is braked by a brake. Right end in FIG. 8 (a) shows the state of the hoisting machine 204b at time _{T 7.}
FIG. 8 (c) shows the output torque (τ _{0 in the} drawing) required for constant travel of the hoisting machine 204b and the induction required for acceleration or deceleration of the hoisting machine 204b in the series of operations described above. The output torque of the electric motor 203 (τ ₀ ± τ ₁ shown in the figure) is shown.

  Next, the load of the suspended load is obtained by the acceleration calculation circuit 108, acceleration torque calculation circuit 110, torque setting circuit 109, load estimation circuit 111, torque calculation circuit 112, speed calculation circuit 113, and speed command value conversion circuit 102 shown in FIG. A method of calculating the maximum rotation speed of the induction motor 203 that can be operated with respect to m will be described.

In FIG. 9, when the induction motor 203 rotates at the rotation speed n [r / min], the hoisting machine 204b rotates through the speed reducer 204a, and the load m increases and decreases at the speed v [m / min]. . During acceleration / deceleration when the speed set value N ^* is increasing or decreasing, the torque command value τ ^* , the running torque τ ₀ , and the acceleration / deceleration required torque τ ₁ output from the speed regulator 104 are expressed by Equation 1 There is a relationship.
[Formula 1]
τ ^* = τ ₀ + τ ₁
The running torque τ ₀ in Equation 1 is decomposed into two components shown on the right side of Equation 2.
[Formula 2]
τ ₀ = τ ₀₁ + τ ₀₂
Here, τ ₀₁ : Running torque with respect to load m, τ ₀₂ : Mechanical loss compensation torque

Further, the acceleration / deceleration necessary torque τ ₁ is decomposed into two components shown on the right side of Expression 3.
[Formula 3]
τ ₁ = τ ₁₁ + τ ₁₂
here,
τ ₁₁ : Acceleration / deceleration required torque for load m,
τ ₁₂ : Necessary acceleration / deceleration torque for the electric motor 203 and the hoisting machine 204b

Each of the τ ₀₁ , τ ₁₁ , and τ ₁₂ can be expressed by Equations 4 to 6 from the mechanical specifications of the system.
[Formula 4]
τ ₀₁ = mv / (2πn) [kgfm]
[Formula 5]
τ ₁₁ = (mv ² / 2π ² n ² ) · (1/375) · Δn [kgfm]
[Formula 6]
^{_{τ 12 = (GD 2/375}} ) · Δn [kgfm]

Since the mechanical loss compensation torque τ ₀₂ of this system is mostly based on the efficiency of the speed reducer 204a, a value obtained by the following Equation 7 is preset in the torque setting circuit 109 in advance.
[Formula 7]
τ ₀₂ = {Speed reducer rated output × (1−Speed reducer efficiency) / Motor rated output} × Motor rated torque [kgfm]

As shown in FIG. 10, since the polarity of the mechanical loss compensation torque τ ₀₂ differs depending on the rotation direction of the induction motor 203, the torque setting circuit 109 takes in the detected speed value n and the mechanical loss compensation torque τ having polarity. ₀₂ is output.

The acceleration / deceleration required torque τ ₁₂ shown in Equation 6 is obtained by multiplying the acceleration shaft calculation circuit 110 by a preset motor shaft conversion total flywheel effect GD ² and an acceleration Δn obtained by an acceleration calculation circuit 108 described later. Ask.
The acceleration calculation circuit 110 performs the calculation of Expression 8.
[Formula 8]
Δn = (n _k −n _(k−1) ) / T _s [r / min / s]
here,
_nk : current motor speed detection value [r / min],
n _(k−1) : previous motor speed detection value [r / min], T _s : detection cycle [s]

Since the speed controller 104 controls the deviation between the speed set value N ^* and the speed detection value n to be always zero, the acceleration Δn in Equation 8 is set to the single integrator 103. Some values can also be used.

By substituting the mechanical loss compensation torque τ ₀₂ output from the torque setting circuit 109 and the acceleration / deceleration required torque τ ₁₂ output from the acceleration torque calculation circuit 110 into the expressions 1 to 3, Expression 9 is obtained. .
[Formula 9]
τ ₀₁ + τ ₁₁ = τ ^* −τ ₀₂ −τ ₁₂

That is, since Equation 4, Equation 5, and Equation 9 have the relationship of Equation 4 + Equation 5 = Equation 9, the load estimation circuit 111 calculates the load m based on this relationship.
The torque calculation circuit 112 calculates the running torque τ ₀₁ based on the load m output from the load estimation circuit 111 and Formula 4, and similarly calculates the acceleration / deceleration required torque τ ₁₁ from Formula 5.

Next, calculation of the operable maximum speed command value N ₀ ^# by the speed calculation circuit 113 will be described.
First, the calculated value τ ₁₂ of the acceleration torque calculating circuit 110, the set value τ _{02 of} the torque setting circuit 109, the calculated values τ ₀₁ and τ _{11 of} the torque calculating circuit 112, and the induction necessary for acceleration / deceleration of the hoisting machine 204b. There is a relationship of Formula 10 with the maximum value τ _M1 of the output torque of the electric motor 203.
[Formula 10]
τ _M1 = | τ ₀₁ + τ ₀₂ | + | τ ₁₁ + τ ₁₂ |

Next, the speed value N ₀₁ ^# of the motor 203 corresponding to τ _M1 in the short-time allowable torque-rotation speed characteristic diagram of the induction motor 203 shown in FIG. 11 (only the first quadrant is shown) is obtained by Expression 11. .
[Formula 11]
N ₀₁ ^# = (τ _A / τ _M1 ) · N _B
here,
N _B : Rated speed of the electric motor 203,
τ _A : Short-time operation allowable torque at the rated speed of the electric motor 203

In addition, when applied to a system with a long lifting distance, the time required to move the hoisting machine 204b up and down at a constant speed also increases, so that the maximum output torque of the induction motor 203 necessary for constant speed operation of the hoisting machine 204b is increased. The value τ _M2 is obtained by Equation 12.
[Formula 12]
τ _M2 = | τ ₀₁ + τ ₀₂ |

Further, the speed value N ₀₂ ^# of the electric motor 203 corresponding to τ _M2 in the characteristic graph of the continuous operation allowable torque-rotational speed of the induction motor 203 shown in FIG. 12 (only the first quadrant is shown) is obtained by Expression 13.
[Formula 13]
N ₀₂ ^# = (τ _B / τ _M2 ) · N _B
here,
N _B : Rated speed of the electric motor 203,
τ _B : Permissible continuous operation torque at the rated speed of the electric motor 203

That is, the speed calculation circuit 113 outputs the smaller one of the N ₀₁ ^{# and} N ₀₂ ^{# as} the operable maximum speed command value N ₀ ^# of the induction motor 203. Alternatively, according to the operation mode of this system, one of the corresponding N ₀₁ ^# or N ₀₂ ^# is selected and output as the maximum operable speed command value N ₀ ^# .
Further, in the speed command value conversion circuit 102, the single integrator 103 is set with the larger one of the command value N ^{# from} the speed commander 101 or the calculated value N ₀ ^{# from} the speed calculation circuit 113 as a new speed command value N ^#. Output to.

  That is, in the prior art of FIG. 6, the maximum operable speed of the induction motor 203 is calculated based on the load estimated by the load estimation circuit 111, the short-time and continuous allowable torque-speed characteristics of the induction motor 203, and the maximum The induction motor 203 is operated according to the speed. For this reason, when this control device is applied to a system for driving a hoisting device provided in a crane, when the hoisting device is moved up and down with a light load, the operation efficiency of the crane can be improved by moving it up and down at a high speed. .

JP 2001-157479 A (paragraphs [0002] to [0038], FIGS. 8 to 10 and the like)

In the prior art shown in FIG. 6, the speed of the hoisting machine at light load is changed as a method for improving the operation efficiency of the crane.
Here, FIG. 13 is an overall configuration diagram of a crane including a hoisting device and a traversing device, where 1 is a trolley, 2 is a garter, 3 is a hoisting device, 4 is a traversing device, and 5 is a suspended load.

In FIG. 13, when an arbitrary movement locus of the suspended load 5 is specified and the hoisting device 3 and the traversing device 4 are controlled, for example, as shown in FIG. 14, the suspended load 5 is moved from the starting point A to the point G. It is conceivable to continuously perform a winding operation, a traversing operation for moving from point G to point H, and a lowering operation for moving from point H to the end point F. At this time, the speed patterns of the hoisting device 3 and the traversing device 4 are as shown in FIG. 15, and each operation is independent of each other along the time axis.
Therefore, when the conventional technique is applied to the control of the crane, there is no particular problem because the hoisting speed, the lowering speed, and the traversing speed may be controlled.

However, as shown in FIG. 16, a hoisting operation for moving the suspended load 5 from point A to point B, an operation for traversing while hoisting from point B to point C, a traversing operation for moving from point C to point D, In the case of continuously performing the operation of traversing while lowering from the D point to the E point and the lowering operation of moving from the E point to the F point, the movement from the B point to the C point as shown in FIG. At the time of movement from the point D to the point E, the winding operation and the traversing operation are performed simultaneously.
In order for the suspended load 5 to pass through the points C and E, the positions of the points D and E are set using the speeds of the hoisting device 3 and the traversing device 4, or the points D and E are passed. It is necessary to set the speeds of the hoisting device 3 and the traversing device 4.

Here, in the prior art, since the hoisting speed is changed by the load m of the suspended load 5 during the operation of the hoisting device 3, an automatic operation in which the hoisting operation and the traversing operation are simultaneously performed as described above is realized. In this case, there is a problem that it becomes difficult to pass the point D and the point E.
In addition, the movement trajectory from point B to point E in FIG. 16 is set so as to avoid a collision with an obstacle existing inside. For this reason, when the hoisting speed is changed according to the estimated load of the suspended load, the risk of colliding with an obstacle should not increase due to the change of the movement trajectory accompanying the speed change, but the prior art avoids that risk It was difficult.

  Therefore, a problem to be solved by the present invention is to control a crane that reliably moves a suspended load along an arbitrary trajectory and does not collide with an obstacle even when a hoisting operation and a traversing operation are performed simultaneously. To provide an apparatus.

In order to solve the above-mentioned problems, an invention according to claim 1 is a crane control device comprising: a hoisting device that drives a hoisting mechanism with a hoisting motor; and a traverse device that drives the traversing mechanism with a traversing motor. A controller for controlling the hoisting motor and the traversing motor to drive the hoisting mechanism and the traversing mechanism to move a suspended load along a predetermined movement trajectory,
Locus generating means for generating a movement locus of the suspended load such that the suspended load passes through an arbitrary target point;
Electric motor control means for controlling the rotational position and speed of each electric motor based on the movement trajectory,
Load estimating means for estimating the load of the suspended load from the state quantity of the hoisting motor;
Speed calculating means for calculating the maximum operable speed command value of each electric motor from the load of the suspended load estimated by the load estimating means, mechanical loss torque and acceleration torque, and
The locus generation means recalculates the movement locus based on the maximum operable speed command value during the operation of the crane.

The invention according to claim 2 is the crane control apparatus according to claim 1,
The hoisting device and the traversing device are operable simultaneously, and the trajectory generating means is based on parameters including at least a starting point and an end point of the moving trajectory, and the speeds of the hoisting motor and the traversing motor, The movement trajectory is recalculated.

The invention according to claim 3 is a crane control device comprising: a hoisting device that drives a hoisting mechanism with a hoisting motor; and a traverse device that drives the traversing mechanism with a traversing motor, the hoisting motor and In the control device for moving the suspended load along a predetermined movement trajectory by controlling the electric motor for traversing and driving the hoisting mechanism and the traversing mechanism,
Locus generating means for generating a movement locus of the suspended load such that the suspended load passes through an arbitrary target point;
Electric motor control means for controlling the rotational position and speed of each electric motor based on the movement trajectory,
Load estimating means for estimating the load of the suspended load from the state quantity of the hoisting motor;
Speed calculating means for calculating the maximum operable speed command value of each electric motor from the load of the suspended load estimated by the load estimating means, mechanical loss torque and acceleration torque, and
The locus generation means corrects the sequential position command for each electric motor based on the maximum operable speed command value.

The invention according to claim 4 is a crane control device comprising: a hoisting device that drives a hoisting mechanism with a hoisting motor; and a traverse device that drives the traversing mechanism with a traversing motor, the hoisting motor and In the control device for moving the suspended load along a predetermined movement trajectory by controlling the electric motor for traversing and driving the hoisting mechanism and the traversing mechanism,
Locus generating means for generating a movement locus of the suspended load such that the suspended load passes through an arbitrary target point;
Electric motor control means for controlling the rotational position and speed of each electric motor based on the movement trajectory,
Load estimating means for estimating the load of the suspended load from the state quantity of the hoisting motor;
Hoisting maximum speed calculating means for calculating the maximum speed of the hoisting motor from the load of the suspended load estimated by the load estimating means, the mechanical loss torque of the hoisting device, and the acceleration torque;
A traverse maximum speed calculating means for calculating the maximum speed of the traverse motor based on the traverse distance to the target point of the suspended load and the acceleration / deceleration time;
The speeds of the hoisting motor and the traversing motor are such that the speed of the hoisting device does not exceed the maximum speed of the hoisting motor and the speed for the traversing device does not exceed the maximum speed of the traversing motor. Calculate the maximum speed command value that can be operated for each electric motor so that the ratio is constant,
The trajectory generating means corrects the sequential position command for each electric motor based on each operable maximum speed command value.

  According to the first aspect of the invention, the trajectory generating means recalculates the movement trajectory using the maximum operable speed command value for the hoisting device and the traversing device, so that the hoisting device is used when the suspended load is light. And while operating the traversing device at a high speed, the suspended load can be controlled to pass through a preset target point.

  According to the second aspect of the present invention, the trajectory generating means can generate the moving trajectory based on parameters such as the starting point and end point of the moving trajectory and the speeds of the hoisting motor and the traversing motor.

  According to the invention of claim 3, the maximum loadable speed command value is calculated so that the speed ratio between the hoisting motor and the traversing motor is constant, and the amount of sequential movement of the suspended load is corrected, thereby When the load is light, the hoisting device and the traversing device can be operated at a high speed so that the suspended load passes through a preset target point.

  According to the invention of claim 4, when obtaining the maximum hoisting speed, the traverse maximum speed that can be realized in relation to the traverse distance to the target point of the crane and the acceleration / deceleration time is obtained, and these are satisfied. In order to change the maximum speed command value for hoisting operation and the maximum speed for traversing operation so that the speed ratio does not change, the suspended load will pass through the target point set in advance regardless of the conditions such as the traversing distance. Can be operated.

It is a block diagram which shows embodiment of this invention. It is a figure which shows an example of the movement locus | trajectory of a suspended load in embodiment of this invention. It is a flowchart which shows operation | movement of the speed determination correction means in embodiment of this invention. It is a time chart which shows an example of the speed and torque in traversing and winding operation. It is a flowchart of the process which determines the hoisting operation possible maximum speed command value and the traverse driving possible maximum speed command value. It is a block diagram which shows a prior art. It is a time chart which shows the relationship between a speed command value and a speed setting value. It is operation | movement explanatory drawing of the system which drives a winding machine and a load with an induction motor. It is a whole lineblock diagram of a system which drives a hoisting machine and a load with an induction motor. It is a characteristic view which shows the relationship between the rotational speed of an induction motor and a mechanical loss compensation torque. It is a characteristic view which shows the relationship between the rotational speed of an induction motor and a short time driving | operation allowable torque. It is a characteristic view which shows the relationship between the rotational speed of an induction motor and continuous driving | operation allowable torque. It is explanatory drawing of the crane which has a winding apparatus and a traversing apparatus. It is a figure which shows the movement locus | trajectory of a suspended load. It is a time chart which shows a winding apparatus speed and a traverse apparatus speed. It is a figure which shows the movement locus | trajectory of a suspended load. It is a time chart which shows the relationship between a winding apparatus speed and a traverse apparatus speed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a control device according to this embodiment.
In FIG. 1, 11 is a traversing mechanism for driving a trolley for moving a suspended load in the horizontal direction, 12 is a rope hoisting mechanism for moving the crane's suspended load in the vertical direction, and 13 and 14 are a traversing mechanism 11 and a hoisting mechanism. Reference numerals 12 and 16 denote position detecting means such as a rotary encoder and a resolver for detecting the rotation angle and speed of each of the motors 13 and 14, respectively.

Here, the traversing mechanism 11 includes a transmission, a drum, and the like, and feeds a rope with the drum to traverse the trolley. The hoisting mechanism 12 includes a transmission, a drum, and the like, and winds or feeds a rope with the drum to move the suspended load up and down.
Reference numeral 50 denotes a traversing device including the traversing mechanism 11 and the traversing electric motor 13, and 60 denotes a hoisting device including the hoisting mechanism 12 and the hoisting electric motor 14.

Next, reference numeral 17 denotes electric motor control means for controlling the electric motors 13 and 14.
In this motor control unit 17, 18 and 19, the speed command value _{^{n t *, t h * [}} rad / s] inverter to each variable speed drive electric motor 13 and 14 as inputs, 20 and 21, the electric motor 13, detection position 14 (suspension corresponding to the position of the _load) p _t, p h sequential position command and feedback the _{^{[rad] p t *, p}} h * speed command value so as to follow the [rad] _n ^t *, _n Position control means for outputting _h ^* [rad / s]. The inverters 18 and 19 are supplied with DC power from the converter 23 connected to the AC power source 22, and the energy generated when the suspended load is lowered can be regenerated to the AC power source 22 via the converter 23. In the symbols relating to speed and position, the subscript t indicates a value in the traverse direction, and the subscript h indicates a value in the winding direction.

Reference numeral 24 denotes a trajectory generating means for generating the trajectory of the suspended load.
This trajectory generating means 24 is a coordinate E (x _E , y _E ) [m] of the end point of the suspended load movement in the two-dimensional coordinate system of the hoisting / lowering direction of the suspended load and the transverse direction by the movement of the trolley. The coordinates Z (x _Z , y _Z ) [m] of the obstacle located between the start point and the end point, the minimum height Y _Amin [m] at the start of _{traversing, and} the minimum height Y _Dmin [m] at the end of _traversing ], The speed command values N _t ^* and N _h ^* [rad / s] of the motors 13 and 14 when the weight of the suspended load is the rated value, the maximum operable speed command values N _t ^## and N _h ^## [ rad / s], an acceleration command value [Delta] n _t ^*, as input ^{_{Δn h * [rad / s 2}} ], the position _{p t, p} h [successive position command in accordance with ^{_{rad] p t *, p h}} * [rad] Is output.

Next, the maximum operable speed command values N _t ^## and N _h ^## given to the trajectory generating means 24 are calculated based on the winding speed n _h and the torque command τ ^* output from the winding inverter 19. Will be described.
The acceleration calculation means 25 calculates the winding acceleration Δn _h [rad / s ² ] from the winding speed n _h [rad / s] of the winding motor 14. Winding accelerating torque calculating means 26 calculates the _{h12 [N} · m] of winding deceleration required torque τ required for the acceleration [Delta] n _h winder excluding load suspended load from 60 winding accelerated or decelerated.

Further, the hoisting torque setting means 27 determines the sign of the hoisting mechanical loss compensation torque τ _h02 [N · m] set in advance from the hoisting speed n _h and outputs it. The load estimation means 28 _suspends from the torque command τ ^{* of} the hoisting motor 14 output from the inverter 19, the hoisting speed n _h , the hoisting acceleration Δn _h , the hoisting acceleration / deceleration necessary torque τ _h12 , and the hoisting mechanical loss compensation torque τ _h02 . Estimate and output the load m of the load.
The hoisting torque calculating means 29 calculates hoisting acceleration / deceleration necessary torque τ _h11 and hoisting running torque τ _h01 with respect to the load m from the hoisting acceleration Δn _h and the load m.

The traverse acceleration torque calculating means 30 calculates a traverse acceleration / deceleration necessary torque τ _t12 necessary for accelerating / decelerating the traverse device 50 excluding the load of the suspended load from the traverse acceleration command Δn _t ^* .
The traverse torque calculating means 31 calculates the suspended load traverse acceleration / deceleration required torque τ _t11 with respect to the load m from the traverse acceleration command Δn _t ^* and the load m.

Reference numeral 32 denotes a speed calculation means including a winding speed calculation means 33, a traverse speed calculation means 34, and a speed determination correction means 35.
The hoisting speed calculation means 33 calculates the hoisting maximum speed command value N _h ^# from the hoisting acceleration / deceleration necessary torque τh ₁₂ , hoisting mechanical loss compensation torque τ _h02 , hoisting running torque τ _h01 , and suspended load acceleration / deceleration necessary torque τ _h11. . The traverse speed calculation means 34 calculates the traverse maximum speed command value N _t ^# from the traverse acceleration / deceleration necessary torque τ _t12 , the suspended load traverse acceleration / deceleration necessary torque τ _t11 , and the traverse mechanical loss compensation torque τ _t02 set from the outside. Calculate.
Further, the speed judgment correcting means 35 is configured to use the maximum hoist speed command value N _h ^# , the traverse maximum speed command value N _t ^# , and the speed command values N _t ^* and N _h ^* when the weight of the suspended load is the rated value ^. Is corrected while keeping the ratio between the hoisting speed and the traverse speed constant, and the maximum operable speed command values N _t ^## and N _h ^## are calculated and output to the trajectory generating means 24.

Next, the operation of the crane control device in this embodiment will be described.
The motor control means 17 receives state quantities such as the speeds of the motors 13 and 14 from the position detection means 15 and 16. Position control means 20, 21, feedback as sequential position command _p ^t * is input from the trajectory generating unit _{24, p} ^{h *} position _p t which is output from the inverter 18 and 19 against, _{p h} coincide respectively Control is performed to output speed commands n _t ^* and n _h ^* . The inverters 18 and 19 control the voltage and current so that the speeds n _t and n _h of the motors 13 and 14 follow the speed commands n _t ^* and n _h ^* , respectively, and control the torque and magnetic flux of the motors 13 and 14. .

Next, the operation of the trajectory generation unit 24 will be described.
First, the trajectory generating unit 24 uses the current suspended load position as the starting point O, the coordinate E (x _E , y _E ) of the end point of the movement, and the coordinate Z ( x _Z , y _Z ), the speed command values N _t ^* and N _h ^* when the weight of the suspended load is the rated value, and the position where the suspended load passes with the hoisting direction as the y-axis and the transverse direction as the x-axis To calculate the movement trajectory.
FIG. 2 is an example of the trajectory of the suspended load. O, A, B, C, D, and E in FIG. 2 are equivalent to those obtained by replacing A, B, C, D, E, and F in FIGS.

Here, α, which is the ratio (speed ratio) between the speed command values N _t ^* and N _h ^* , is expressed by Equation 14.
[Formula 14]
α = N _h ^* / N _t ^*

From the O point to the A point, which is the starting point, only the winding operation is performed, and the position of the A point is obtained by Equation 15 using the minimum height Y _Amin at the start of _traversing .
[Formula 15]
A = (X _A , Y _A ) = (0, Y _Amin )

From the point A to the point B, the winding operation and the traversing operation are performed simultaneously. The position of the suspended load during this time is obtained by Expression 16.
[Formula 16]
y = αx + Y _Amin

Further, the point B can be obtained by Expression 17.
[Formula 17]
B = (X _B , Y _B )
_{Here, X B = (Y Z -Y} Amin), Y B = Y Z

From point B to point C, only the traversing operation is performed with the suspended load height being constant. The position of the point C can be obtained by Equation 18 using the minimum height Y _Dmin at the end of the traversal at the point D, the speed ratio α, and the coordinates E of the end point.
[Formula 18]
C = (X _C , Y _C )
_{Here, X C = X E - (} Y Z -Y Dmin) / α, Y C = Y Z

From the point C to the point D, the lowering operation and the traversing operation are performed simultaneously. The position of the suspended load during this time is obtained by Expression 19.
[Formula 19]
y = −α (x−X _E ) + Y _Dmin
Further, the position of the point D can be obtained by Expression 20.
[Formula 20]
D = (X _D , Y _D ) = (X _E , Y _Dmin )

Furthermore, from point D to point E, there is no traversing motion and only a lowering motion. Point E is a coordinate input from the outside, and is expressed by Equation 21.
[Formula 21]
E = (X _E , Y _E )
The actual movement trajectory is not ideal because it accompanies acceleration / deceleration, and swells outward. For this reason, the suspended load passes outside the position Z of the obstacle, and there is no particular problem.

The operation of the acceleration calculating means 25 in FIG. 1 is the same as that of the acceleration calculating circuit 108 in FIG. 6, and the hoisting acceleration Δn _h is obtained from the hoisting speed n _h output from the inverter 19 in the electric motor control means 17 by Equation 22. .
[Formula 22]
Δn _h = (n _h [k] −n _h [k−1]) / T _s [rad / s ² ]
Since the acceleration calculation means 25 is realized by a calculation device such as a microcomputer or a programmable controller, it calculates discrete values, k is a sampling number, and T _s is a sampling period [s].

The operation of the hoisting acceleration torque calculating means 26 is the same as that of the acceleration torque calculating circuit 110 in FIG. 6, and the hoisting acceleration / deceleration necessary torque τ _h12 is obtained by Expression 23.
[Formula 23]
τ _h12 = J _hm · Δn _h [N · m]
Here, J _hm is a moment of inertia [kg · m ² ] obtained by converting a presettable mechanism such as an electric motor, a speed reducer, a drum, and a lifting tool into the electric motor shaft.

The operation of the hoisting torque setting means 27 is the same as that of the torque setting circuit 109 in FIG. 6, and the hoisting mechanical loss compensation torque τ _h02 is set by Expression 24.
[Formula 24]
τ _h02 = { _Speed reducer rated output × (1− _Speed reducer efficiency) / Motor rated output} × Motor rated torque As in the prior art, the hoisting mechanical loss compensation torque τ _h02 differs depending on the rotation direction of the motor 14. Based on the winding speed n _h [rad / s], the polarity of the winding mechanical loss compensation torque τ _h02 is changed and output.

The operation of the load estimator 28 is the same as that of the load estimator circuit 111 in FIG. 6, and estimates the load m of the suspended load from the relationship of Equation 25, Equation 26, and Equation 27.
[Formula 25]
τ _h01 = (V _h / N _h ) mg [N · m]
here,
g: gravity acceleration,
V _h : Rated speed [m / s] of the suspended load at the time of winding,
N _h : Rated speed of the hoisting motor 14 [rad / s]
[Formula 26]
τ _h11 = (V _h ² / N _h ² ) · m · Δn _h [N · m]
Here, (V _h ² / N _h ² ) · m corresponds to the moment of inertia of the load in terms of the motor shaft.
[Formula 27]
τ _h01 + τ _h11 = τ _h ^* _{−τ h02 −τ h12} [N · m]

The operation of the winding torque calculation means 29 is the same as that of the torque calculation circuit 112 in FIG. That is, the hoisting running torque τ _h01 is obtained from the load m estimated by the load estimating means 28 and the mathematical expression 25, and similarly the hoisting acceleration / deceleration necessary torque τ _h11 is obtained from the load m and the mathematical expression 26.

The operation of the winding speed calculation means 33 is the same as that of the speed calculation circuit 113 in FIG.
Here, τ _h12 , τ _h02 , τ _h01 , τ _h11 and the output torque maximum value τ _hM1 of the hoisting motor 14 necessary for acceleration / deceleration of the hoisting mechanism 12 have a relationship of Equation 28.
[Formula 28]
τ _hM1 = | τ _h01 + τ _h02 | + | τ _h11 + τ _h12 |
_Assuming that the short-time operation allowable torque-rotational speed characteristics of the hoisting motor 14 are as shown in FIG. 11 described above, the maximum speed command value N _h01 ^# in the short-time operation of the motor 14 corresponding to the output torque maximum value τ _hM1 is Ask.
The speed value N ₀₁ ^# is expressed by Equation 29.
[Formula 29]
N _h01 ^# = (τ _hA / τ _hM1 ) · N _hB
here,
N _hB : Rated speed of the motor 14
τ _hA : Short-time operation allowable torque at the rated speed of the motor 14

Further, the output torque maximum value τ _hM2 of the electric motor 14 necessary for the continuous operation is expressed by Expression 30.
[Formula 30]
τ _hM2 = | τ _h01 + τ _h02 | [N · m]

At this time, the maximum speed value N _h02 ^# of the electric motor 14 corresponding to the τ _hM2 in the continuous operation allowable torque-rotational speed characteristic of FIG.
The maximum speed value N _h02 ^# during this continuous operation is expressed by Equation 31.
[Formula 31]
N _h02 ^# = (τ _hB / τ _hM2 ) · N _hB [rad / s]
here,
τ _hB : Permissible torque for continuous operation at the rated speed of the motor 14

The winding speed calculation means 33 compares N ₀₁ ^# and N _h02 ^# as in the speed calculation circuit 113 of FIG. 6 and _outputs the lower speed as the winding maximum speed command value N _h ^# .

The traverse acceleration torque calculating means 30 calculates the traverse acceleration / deceleration necessary torque τ _t12 using Equation 32
[Formula 32]
τ _t12 = J _tm · Δn _t ^* [N · m]
Here, J _tm is an inertia moment [kg · m ² ] obtained by converting a presettable mechanism such as an electric motor, a reduction gear, a drum, and a lifting tool to the electric motor shaft, excluding the load m of the suspended load.

The traverse torque calculation means 31 calculates the necessary load traverse acceleration / deceleration torque τ _t11 using the load m of the load and the traverse acceleration command Δn _t ^{* according} to Equation 33.
[Formula 33]
τ _t11 = V _t ² / N _t ² · m · Δn _t ^* [N · m]
here,
V _tB : Rated speed of trolley [m / s],
N _tB : Rated speed of motor 13 [rad / s]
V _t ² / N _t ² · m is an expression for converting the load m of the suspended load into the equivalent moment of inertia of the motor shaft.

Next, the traverse speed calculation means 34 will be described.
The traverse speed calculating means 34 receives the traverse acceleration / deceleration necessary torque τ _t12 , the traverse load necessary acceleration / deceleration necessary torque τ _t11 , and the traverse mechanical loss compensation torque τ _t02 set from the outside, and inputs the _traverse speed of the trolley including the suspended load. The maximum value τ _tM1 of the output torque of the electric motor 13 necessary for the transverse acceleration / deceleration is calculated by Equation 34.
[Formula 34]
τ _tM1 = τ _t02 + τ _t11 + τ _t12

Further, similarly to the hoisting operation, the maximum speed command value N _t ^# of the motor 13 corresponding to the τ _tM1 is _obtained in the short-time operation allowable torque-rotational speed characteristic diagram of FIG.
The speed value N _t ^# is expressed by Equation 35.
[Formula 35]
N _t ^# = (τ _tA / τ _tM1 ) · N _tB
here,
τ _tA : short-time operation allowable torque at the rated speed of the motor 13

Note that the maximum value τ _tM2 of the output torque of the electric motor 13 necessary for the continuous operation is a value corresponding to the traverse mechanical loss compensation torque τ _{t02 as} shown in Expression 36.
[Formula 36]
τ _hM2 − = τ _h02 [N · m]

Next, the speed determination correction means 35 in FIG. 1 will be described.
As shown in FIG. 3, the speed determination correction means 35 receives the maximum speed command values N _t ^# and N _h ^# at the time of traversing and winding, and the speed command values N _t ^* and N _h ^* at the time of rating as inputs. Then, the respective acceleration rates γ _t and γ _h are calculated (step S1). In order to pass through the points B and D in the movement trajectory of FIG. 2 while changing the speed, it is necessary to keep the speed ratio α shown in Equation 14 constant.
Therefore, the magnitude relationships between the acceleration rates γ _t and γ _h are compared (step S2), the maximum speed command values N _t ^# and N _h ^# are corrected to match the smaller acceleration rate, and the maximum operable speed command value is set. Output as N _t ^## and N _h ^## (steps S3 and S4).
When the maximum ^drivable speed command values N _t ^## and N _h ^## are fixedly output from the speed determination correction means 35, the trajectory generating means 24 sequentially outputs the position commands p _t ^* and _ph ^* to the maximum drivable speed command. Correction is made to accelerate to values N _t ^## and N _h ^## .

FIG. 4 shows an example of the speed and torque waveforms in the traversing / winding operation.
In the speeds of the hoisting device 60 and the traversing device 50, the broken line is the speed waveform operated at the rated speed. A solid line is a speed waveform when the present embodiment is applied. The load of the suspended load is estimated at the acceleration of the hoisting operation, and the maximum operable speed command values N _t ^## and N _h ^## are determined. .
The sequential position command p _h ^* at the time of the winding operation is recalculated so that the speed becomes N _h ^## while continuing the acceleration, and the sequential position command p _t ^* at the time of the traverse operation is also the speed of N _t ^## Recalculated to be As a result, the hoisting device 60 and the traversing device 50 can be efficiently operated at an appropriate speed according to the load m of the suspended load without changing the trajectory of the suspended load.

In the above-described embodiment, the maximum operable speed command value is set so that the speed ratio α is equal to the rated speed. However, depending on the conditions under which the movement locus can be changed, N _t ^## = N _t ^# , N _h ^## = N _h ^# .
Further, the physical quantity of the rotating system around the electric motor may be replaced with the physical quantity of the direct acting system on the suspended load side.

The hoisting speed upper limit value is mainly governed by the load of the suspended load, whereas the traverse speed upper limit value is governed mainly by the traversing distance and the acceleration / deceleration time.
In general, the acceleration / deceleration time during traversing needs to be set based on the rope length or the like so as to suppress the swing of the suspended load. For this reason, the acceleration / deceleration distance becomes longer as the traverse speed is increased, and it is not possible to set a traverse speed at which this distance becomes longer than the traverse distance. Even in such a situation, in order to pass the target point set in advance while keeping the speed ratio α constant, when the maximum speed is obtained by load estimation, the hoisting and traversing operation can be performed according to the procedure shown in FIG. The maximum speed command value should be determined.

Here, the maximum speed obtained by load estimation is set as the first maximum winding speed (step S11). Thereafter, the traverse maximum speed is calculated from the traverse distance and the acceleration / deceleration time so that the traverse acceleration / deceleration distance stays below the traverse distance to the target point (step S12).
Next, a value obtained by multiplying the traverse maximum speed by the speed ratio α is obtained as a second hoisting maximum speed (step S13). Then, the first hoisting maximum speed is compared with the second hoisting maximum speed, and the hoisting operation possible maximum speed command value is determined with the smaller value (step S14).
Finally, a traverse operation maximum speed command value is determined by a value obtained by dividing the determined hoist operation maximum speed command value by the speed ratio α (step S15).

Thus, it determined winding with drivable maximum speed command value and the traverse operation is possible up to a speed command value, the sequential position command p _{t *} for the suspended load trajectory generating unit ^24, by going to update the p _h ^* Regardless of conditions such as the traversing distance, the suspended load can be operated so as to pass through a preset target position.

1: trolley 2: garter 3: hoisting device 4: traversing device 5: suspended load 11: traversing mechanism 12: hoisting mechanism 13: traversing electric motor 14: hoisting electric motor 15, 16: position detecting means 17: electric motor control means 18, 19: Inverter 20, 21: Position control means 22: AC power supply 23: Converter 24: Trajectory generation means 25: Acceleration calculation means 26: Hoisting acceleration torque calculating means 27: Hoisting torque setting means 28: Load estimating means 29: Hoisting torque calculation Means 30: Traverse acceleration torque calculation means 31: Traverse torque calculation means 32: Speed calculation means 33: Winding speed calculation means 34: Traverse speed calculation means 35: Speed determination correction means 50: Traverse device 60: Hoisting device

The invention according to claim 4 is a crane control device comprising: a hoisting device that drives a hoisting mechanism with a hoisting motor; and a traverse device that drives the traversing mechanism with a traversing motor, the hoisting motor and In the control device for moving the suspended load along a predetermined movement trajectory by controlling the electric motor for traversing and driving the hoisting mechanism and the traversing mechanism,
Locus generating means for generating a movement locus of the suspended load such that the suspended load passes through an arbitrary target point;
Electric motor control means for controlling the rotational position and speed of each electric motor based on the movement trajectory,
Load estimating means for estimating the load of the suspended load from the state quantity of the hoisting motor;
The maximum speed calculating means winding for calculating the maximum speed of the motor for winding said from the mechanical loss torque and acceleration torque of the hoisting device and the load of the suspended load estimated by the load estimation means,
A traverse maximum speed calculating means for calculating the maximum speed of the traverse motor based on the traverse distance to the target point of the suspended load and the acceleration / deceleration time;
Speed between the speed of the hoisting apparatus does not exceed the maximum speed of the motor for winding said, and the velocity of transverse equipment is said hoist electric motor under a condition that does not exceed the maximum speed of the transverse electric motor the transverse electric motor Calculate the maximum speed command value that can be operated for each electric motor so that the ratio is constant,
The trajectory generating means corrects the sequential position command for each electric motor based on each operable maximum speed command value.

Claims (4)

A crane control device comprising: a hoisting device that drives a hoisting mechanism with a hoisting motor; and a traversing device that drives a traversing mechanism with a traversing motor, the control device controlling the hoisting motor and the traversing motor. In the control device for moving the suspended load along a predetermined movement locus by driving the winding mechanism and the traversing mechanism,
Locus generating means for generating a movement locus of the suspended load such that the suspended load passes through an arbitrary target point;
Electric motor control means for controlling the rotational position and speed of each electric motor based on the movement trajectory,
Load estimating means for estimating the load of the suspended load from the state quantity of the hoisting motor;
Speed calculating means for calculating the maximum operable speed command value of each electric motor from the load of the suspended load estimated by the load estimating means, mechanical loss torque and acceleration torque,
With
The trajectory generating means includes
A crane control apparatus that recalculates the movement trajectory based on the maximum operable speed command value during operation of the crane. In the crane control apparatus according to claim 1,
The hoisting device and the traversing device are operable simultaneously,
The trajectory generating means recalculates the travel trajectory based on parameters including at least a start point and an end point of the travel trajectory, and speeds of the hoisting motor and the traverse motor. Control device. A crane control device comprising: a hoisting device that drives a hoisting mechanism with a hoisting motor; and a traversing device that drives a traversing mechanism with a traversing motor, the control device controlling the hoisting motor and the traversing motor. In the control device for moving the suspended load along a predetermined movement locus by driving the winding mechanism and the traversing mechanism,
Locus generating means for generating a movement locus of the suspended load such that the suspended load passes through an arbitrary target point;
Electric motor control means for controlling the rotational position and speed of each electric motor based on the movement trajectory,
Load estimating means for estimating the load of the suspended load from the state quantity of the hoisting motor;
Speed calculating means for calculating the maximum operable speed command value of each electric motor from the load of the suspended load estimated by the load estimating means, mechanical loss torque and acceleration torque,
With
The trajectory generating means includes
A crane control apparatus that corrects a sequential position command for each electric motor based on the maximum operable speed command value. A crane control device comprising: a hoisting device that drives a hoisting mechanism with a hoisting motor; and a traversing device that drives a traversing mechanism with a traversing motor, the control device controlling the hoisting motor and the traversing motor. In the control device for moving the suspended load along a predetermined movement locus by driving the winding mechanism and the traversing mechanism,
Locus generating means for generating a movement locus of the suspended load such that the suspended load passes through an arbitrary target point;
Electric motor control means for controlling the rotational position and speed of each electric motor based on the movement trajectory,
Load estimating means for estimating the load of the suspended load from the state quantity of the hoisting motor;
Hoisting speed upper limit calculating means for calculating the upper speed limit of the hoisting motor from the load of the suspended load estimated by the load estimating means, the mechanical loss torque of the hoisting device, and the acceleration torque;
A traverse speed upper limit calculating means for calculating an upper limit speed of the traverse motor based on the traverse distance to the target point of the suspended load and the acceleration / deceleration time;
With
The hoisting motor and the traverse motor are operated under the condition that the maximum speed of the hoisting device does not exceed the upper speed limit of the hoisting motor and the maximum speed for the traversing device does not exceed the upper speed limit of the traverse motor. Calculate the maximum speed of each motor so that the speed ratio with the motor is constant,
The crane control device, wherein the trajectory generating means corrects a sequential position command for each electric motor based on each maximum speed.

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