LU502155A1

LU502155A1 - Anti-sway control method and bridge crane

Info

Publication number: LU502155A1
Application number: LU502155A
Authority: LU
Inventors: Wenduo Lin; Cheng Zhang; Jie Li; Xueqi Chang; Meng Zhang; Jiangsong Lan
Original assignee: Eurocrane China Co Ltd
Priority date: 2021-04-30
Filing date: 2021-12-08
Publication date: 2022-05-30
Also published as: LU502155B1; CN113200451A; CN113200451B; WO2022227585A1

Abstract

The present invention provides an anti-sway control method and a bridge crane. The anti-sway control method includes: starting a crane or a trolley, and determining a starting acceleration pulse A0 and an anti-driving-sway acceleration pulse A1; calculating a theoretical driving sway angle θ1; measuring a first actual sway angle θ2, calculating a disturbance sway angle θ3 and determining whether it is greater than the minimum disturbance sway angle, if not, controlling the crane or the trolley in operation based on the anti-driving-sway acceleration pulse A1, if yes, controlling the crane or the trolley in operation based on the anti-driving-sway acceleration pulse A1, calculating a first anti-disturbance-sway acceleration pulse A2 and controlling the crane or the trolley in operation based on the first anti-disturbance-sway acceleration pulse A2; in a uniform-velocity phase, measuring a second actual sway angle θ3 and determining whether it is greater than the minimum disturbance sway angle, if yes, calculating a second anti- disturbance-sway acceleration pulse A3 and controlling the crane or the trolley in operation based on the second anti-disturbance-sway acceleration pulse A3; and repeating the steps in the uniform-velocity phase. This anti-sway control method enables closed-loop control over sway of the lifting hook with high accuracy and allows efficient operation of the bridge crane.

Description

ANTI-SWAY CONTROL METHOD AND BRIDGE CRANE LU502155

FIELD OF THE INVENTION The present invention relates to the technical field of bridge crane control, more particularly, to an anti-sway control method and a bridge crane.

DESCRIPTION OF THE RELATED ART Bridge cranes are important logistics transportation equipment. Currently, during manual operation of a lifter, such as a clamshell lifter or an electromagnetic lifter, of the bridge crane for material handling, the lifted weight always sways, which causes decreased operation efficiency and presents certain safety hazards. Currently, the anti-sway technique commonly used on the market is the electronic open-loop anti-sway technique that focuses on an optimized design of the control algorithm of the driving inverter on the crane or the trolley in the bridge crane, in which the control elements, such as the actual sway length, the actual sway angle, are mostly determined by indirect calculation or defined through input. However, deflection of the bridge crane in practical engineering is caused by combined factors, including both its own sway during weight lifting and sway due to external interferences. Therefore, determination of the numeric values of the anti-sway control elements through indirect calculation or open-loop definition cannot be easily controlled specifically depending on actual operating conditions, thereby causing low control accuracy and low operating efficiency of anti-sway control.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an anti-sway control method and a bridge crane, c to solve the problems of low control accuracy and low operating efficiency of the anti- sway method based on open-loop control during operation of the bridge crane. In view of this object, the present invention adopts the following technical solutions. An anti-sway control method is provided for controlling sway of a lifting hook in a bridge crane during an acceleration phase and a uniform-velocity phase, the bridge crane including an anti- sway controller, a crane and a trolley in transmission connection with the crane, the lifting hook being in transmission connection with the trolley, the crane and the trolley both being provided with a sway angle sensor, the anti-sway controller is used for applying an anti-sway acceleration pulse A to the crane or the trolley. The method includes the following steps.

S100: starting the crane or the trolley based on the starting acceleration ao, and determining, by LU502155 the anti-sway controller, the starting acceleration pulse A, and the anti-driving-sway acceleration pulse A, based on the starting acceleration ag.

S200: calculating the theoretical driving sway angle 6, of the lifting hook based on the starting acceleration pulse Ag.

S300: measuring, by the sway angle sensor, the first actual sway angle 6, of the lifting hook, and calculating the disturbance sway angle 03 based on the theoretical driving sway angle 0, and the first actual sway angle 6,. S400: determining whether the disturbance sway angle 6; is greater than the minimum disturbance sway angle, and if so, proceeding to S500, otherwise proceeding in sequence to S610, S620 and S630. S500: controlling, by the anti-sway controller, the driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A, where A=A,. S610: controlling, by the anti-sway controller, the driving motor of the crane or the trolley to operate based on the anti-sway acceleration pulse A, where A=A,. S620: calculating, by the anti-sway controller, a first anti-disturbance-sway acceleration pulse A; based on the disturbance sway angle 03. S630: controlling, by the anti-sway controller, the driving motor of the crane or the trolley to operate based on the anti-sway acceleration pulse A, where A=A,. S700: bringing the crane or the trolley into the uniform-velocity phase, in which the sway angle sensor measures the second actual sway angle 64, determining whether the second actual sway angle 0, is greater than the minimum disturbance sway angle, and if so, proceeding to S800. S800: calculating the second anti-disturbance-sway acceleration pulse A; based on the second actual sway angle 04. S900: controlling, by the anti-sway controller, the driving motor of the crane or the trolley to operate based on the anti-sway acceleration pulse A, where A=A;. S1000: repeating S700 to S900. Preferably, a reel is provided on the trolley.

The lifting hook and the reel are in transmission connection with each other by a lifting rope.

The reel is provided with a sensor for detecting the measured rope length 1; of the lifting rope.

The first sway period T, of the lifting hook during the acceleration phase is calculated according to h= 27g. where T, is the first sway period in s; 1; is the measured rope length in m, and g is the acceleration of gravity in N/Kg.

Preferably, the anti-driving-sway acceleration pulse A; is calculated according to LU502155 cost) A =exp +-——— |* 4,

NI . The starting acceleration pulse Ag and the anti-driving- sway acceleration pulse A; are applied with a difference in timing of KT,+T,/2, where Ty is the first sway period in s; 6 is the first damping coefficient valued in the range of 0 to 1; A is the first frequency in rad/s; and K is a positive integer equal to or greater than zero. Preferably, the step S620 includes specifically the following steps: S621: calculating the first disturbance acceleration a; according to a = ho; + 8b; ; and S622: determining the first disturbance acceleration pulse Ay and the first anti-disturbance- sway acceleration pulse A, based on the first disturbance acceleration a;, where 1; is the measured rope length in m; 0; is the first disturbance sway angle; g is the acceleration of gravity in N/Kg and 0, is the second derivative of the first disturbance sway angle. Preferably, the first anti-disturbance-sway acceleration pulse A, is calculated according to

CE A, =exp| +-——- |* 4, J1=67 and the first disturbance acceleration pulse Ay and the first anti-disturbance-sway acceleration pulse A, are applied with a difference in timing of KT,+T,/2, where Ty is the first sway period in s; 6 is the first damping coefficient valued in the range of 0 to 1; O1 is the first frequency in rad/s; and K 1s a positive integer equal to or greater than zero. Preferably, the step S800 includes specifically: S810: determining the second sway period T, of the lifting hook based on the second actual sway angle 64; S820: calculating the actual rope length 1, according to N, = 27/8 ; S830: calculating the second disturbance acceleration a, based on the actual rope length 1»; and S840: determining the second disturbance acceleration pulse As and the second anti- disturbance-sway acceleration pulse A; based on the second disturbance acceleration a,, where T, is the second sway period in s; I, is the actual rope length in m; and g is the acceleration of gravity in N/Kg. Preferably, the second anti-disturbance-sway acceleration pulse Aj is calculated according to

T LU502155 C0, (47, + - A, =exp| +-—— |* À, | : © a

, and the second disturbance acceleration pulse As and the second anti-disturbance-sway acceleration pulse Az; are applied with a difference in timing of NT,+T,/2, where T, is the second sway period in s; © is the second damping coefficient valued in the range of 0 to 1; ?2 is the second frequency in rad/s; and N is a positive integer equal to or greater than zero.

Preferably, the second disturbance acceleration a, is calculated according to a =L0j+8 0, where | is the actual rope length in m; 04 is the second actual sway angle; g is the acceleration of gravity in N/Kg; and 0; is the second derivative of the second actual sway angle.

Preferably, the step S500 includes specifically the following step: converting, by the anti-sway controller, the anti-driving-sway acceleration pulse A; into an electrical signal and transmitting it to the inverter on the crane or the trolley that controls the driving motor of the crane or the trolley in operation.

The invention also provides a bridge crane adopting the anti-sway control method described above.

As compared with the prior art, the present invention has the following beneficial effects.

It is an object of the present invention to provide an anti-sway control method and a bridge crane for controlling sway of a lifting hook in the bridge crane during an acceleration phase and a uniform-velocity phase.

The bridge crane includes an anti-sway controller, a crane and a trolley in transmission connection with the crane.

The lifting hook is in transmission connection with the trolley, and the crane and the trolley both are provided with a sway angle sensor.

The anti-sway controller is used for applying an anti-sway acceleration pulse A to the crane or the trolley.

The method includes the following steps: starting the crane or the trolley based on the starting acceleration ao, and determining the starting acceleration pulse A, based on the starting acceleration ay and determining the anti-driving-sway acceleration pulse A, based on A, by the anti-sway controller; calculating the theoretical driving sway angle 6, of the lifting hook based on the starting acceleration pulse Ag; measuring, by the sway angle sensor, the first actual sway angle 6, of the lifting hook, and calculating the disturbance sway angle 0; based on the theoretical driving sway angle 0; and the first actual sway angle 6,; determining whether the disturbance sway angle 0; is greater than the minimum disturbance sway angle, and if not, controlling, by the anti-sway controller, the driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A=A y; and if yes, controlling, by the anti- LU502155 sway controller, the driving motor of the crane or the trolley in operation based on the anti- sway acceleration pulse A=A,, calculating the first disturbance acceleration pulse A, based on the disturbance sway angle 0; and determining the first anti-disturbance-sway acceleration pulse A, based on the first disturbance acceleration pulse Au, by the anti-sway controller, controlling, by the anti-sway controller, the driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A=A;; bringing the crane or the trolley into the uniform-velocity phase, in which the sway angle sensor measures the second actual sway angle 0;, determining whether the second actual sway angle 0; is greater than the minimum disturbance sway angle; if yes, calculating the second disturbance acceleration pulse As based on the second actual sway angle 0; and determining the second anti-disturbance-sway acceleration pulse A; based on the second disturbance acceleration pulse As; controlling, by the anti-sway controller, the driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A=A3; and repeating the operation steps in the uniform-velocity phase. In contrast to the open-loop control from prior art, in this anti-sway control method, when the crane or the trolley starts to operate, the crane or the trolley enters the acceleration phase. The sway angle sensor detects the sway angle of the lifting hook in real time during the operation. It is determined whether there is any external disturbance during the acceleration phase based on the angle value detected by the sway angle sensor, so that the anti-sway controller accurately controls the driving motor of the crane or the trolley in operation based on the angle value of the inherent sway and the external disturbance to reduce the sway of the lifting hook to the allowable range. After entering the uniform-velocity phase, the external environment interferes with the normal operation of the bridge crane at uncertain time points. The sway angle sensor detects the sway angle of the lifting hook in real time to determine whether there is any external disturbance. The anti-sway controller controls the driving motor of the crane or the trolley in operation in real time based on the angle value detected by the sway angle sensor to reduce the sway of the lifting hook due to external disturbance to the allowable range. Operation steps in the uniform-velocity phase are repeated to enable closed- loop control over sway of the bucket with high control accuracy, thereby ensuring stable operation of the lifting hook, increasing operation efficiency of the crane or the trolley and improving use security of the bridge crane.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a flow diagram of an anti-sway control method according to an embodiment of the LU502155 present invention; Fig. 2 is a first partial flow diagram of an anti-sway control method according to an embodiment of the present invention; Fig. 3 is a second partial flow diagram of an anti-sway control method according to an embodiment of the present invention; Fig. 4 is a first simulation pulse diagram of an anti-sway control method according to an embodiment of the present invention; Fig. 5 is a second simulation pulse diagram of an anti-sway control method according to an embodiment of the present invention; and Fig. 6 is a third simulation pulse diagram of an anti-sway control method according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described hereinafter in further detail with reference to the drawings and embodiments. It is appreciated that the particular embodiments described here are merely intended to explain the present invention and not to limit it. In addition, for convenience of description, only part of the structure related to the present invention is shown in the drawings, but not all of it. In the description of the present invention, unless otherwise explicitly specified and defined, the terms "jointed", "connected" and "fixed" should be broadly understood, for example, as being fixedly connected, detachably connected or integrated, mechanically connected or electrically connected; directly connected or indirectly connected through an intermediate medium, or the internal communication of two elements or the interaction between two elements. For those of ordinary skills in the field, the specific meanings of the above terms in the present invention can be understood depending on specific contexts. In the present invention, unless otherwise specified and defined, the expression the first feature being "above" or "below" the second feature may include direct contact between the first and second features, or contact between the first and second features through another feature therebetween them. Furthermore, the expression first feature being "on" or "above" the second feature means the first feature is directly above or obliquely above the second feature, or simply indicates that the horizontal height of the first feature is greater than that of the second feature. The expression the first feature being "under" or "below" the second feature means that the first feature is directly below or obliquely below the second feature, or simply indicates that the horizontal height of the first feature is lower than that of the second feature.

LU502155 In the description of this embodiment, the terms "up", "down", "right", etc. represent an orientation or positional relationship as shown in the drawings, which is intended only for convenience of description and simplification of operation, but not for indicating or implying that the indicated device or element must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

In addition, the terms "first" and "second" are merely intended for distinguishment in description and have no special meaning.

The present invention provides an anti-sway control method and a bridge crane.

This anti-sway control method is used to control sway of a lifting hook in a bridge crane during an acceleration phase and a uniform-velocity phase.

Compared with the open-loop control from prior art, in this anti-sway control method, the crane or the trolley enters the acceleration phase when they start to operate.

The sway angle sensor detects the sway angle of the lifting hook in real time during the operation.

It is determined whether there is any external disturbance during the acceleration phase based on the angle detected by the sway angle sensor, so that the anti-sway controller accurately controls the driving motor of the crane or the trolley in operation based on the angle of the inherent sway and the external disturbance, to reduce the sway of the lifting hook to the allowable range.

After entering the uniform-velocity phase, the external environment interferes with the normal operation of the bridge crane at uncertain time points.

The sway angle sensor detects the sway angle of the lifting hook in real time to determine whether there is any external disturbance.

The anti-sway controller controls the driving motor of the crane or the trolley in operation in real time based on the detected angle value to reduce the sway of the lifting hook due to external disturbance to the allowable range.

Operation steps in the uniform-velocity phase are repeated to enable closed-loop control over sway of the bucket with high control accuracy, thereby ensuring stable operation of the lifting hook, increasing operation efficiency of the crane or the trolley and improving use security of the bridge crane.

A lifting hook is in transmission connection with the trolley.

The crane and the trolley are both provided with a sway angle sensor.

An anti-sway controller applies an anti-sway acceleration pulse A to the crane or the trolley.

As shown in Figs. 1-3, this anti-sway control method includes the following steps.

S100: starting the crane or the trolley based on the starting acceleration ao, and determining, by the anti-sway controller, the starting acceleration pulse A; and the anti-driving-sway acceleration pulse A, based on the starting acceleration ao.

LUS02155 Specifically, the crane or the trolley starts and enters the acceleration phase.

The starting acceleration pulse Ag is derived from the starting acceleration ao.

The specific calculation process belongs to prior art and 1s not to be described in detail here.

S200: calculating the theoretical driving sway angle 0, of the lifting hook based on the starting acceleration pulse Ag.

S300: measuring, by the sway angle sensor, the first actual sway angle 6, of the lifting hook, and calculating the disturbance sway angle 03 based on the theoretical driving sway angle 0, and the first actual sway angle 6,. Specifically, the disturbance sway angle 65 is calculated by 0,=6,+04. It is appreciated that the driving sway angle is a sway angle generated by the lifting hook itself when lifting the weight.

The disturbance sway angle is a sway angle generated by external interference.

The driving sway angle and the disturbance sway angle are respectively calculated to facilitate determination of whether there is any external disturbance to the bridge crane as well as determination of the degree of influence of the external disturbance to the bridge crane, thereby facilitating improvement in operation environment of the bridge crane.

S400: determining whether the disturbance sway angle 03 is greater than the minimum disturbance sway angle, and if not, proceeding to S500, if yes, proceeding to S610, S620 and S630 in sequence.

Specifically, if the disturbance sway angle 65 is less than the minimum disturbance sway angle, that is, the value of the disturbance sway angle 0; is in the allowable range, then only the sway generated by the lifting hook itself when lifting the weight needs to be ameliorated.

Therefore, proceed to S500. S500: Controlling, by the anti-sway controller, the driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A=A,. The anti-sway controller converts the anti-driving-sway acceleration pulse A; into an electrical signal and transmits the electrical signal to the inverter on the crane or the trolley.

The inverter controls the driving motor of the crane or the trolley in operation, so that the motor of the crane or trolley outputs corresponding torque for operation to reduce sway of the lifting hook.

It is appreciated that the sway generated by the lifting hook itself when lifting the weight can be improved by the steps described above, so that the value of the driving sway angle of the lifting hook when lifting the weight can be controlled to the allowable range.

A reel is provided on the trolley.

The reel is provided with a sensor for detecting the measured rope length 1; of the lifting rope. The first sway period T, of the lifting hook during the LU502155 acceleration phase is calculated according to h= AA where T, is the first sway period in s; 1, is the measured rope length in m, and g is the acceleration of gravity in N/Kg. The anti-driving-sway acceleration pulse A; is calculated according to C9, (47 + 5) A =exp Tia * À, , where T, is the first sway period in s; 6 is the first damping coefficient valued in the range of 0 to 1; and © is the first frequency in rad/s. The value of the first damping coefficient 6 is set depending on the specific operation conditions during the acceleration phase and 1, Preferably, as shown in Fig.4, an anti-driving-sway acceleration pulse A; is applied with a difference in timing of KT,+T,/2. That is, the anti-driving-sway acceleration pulse A, is applied at a time point where the lifting hook has the maximum sway amplitude, which is the best time point for application of the anti-driving-sway acceleration pulse A,. It is appreciated that, the anti-sway controller applies a pulse of an equal magnitude and in an opposite direction to the lifting hook. Therefore, the sway of the lifting hook is ameliorated in a fastest and most effective way. to is any instant during the acceleration phase in s.

If the disturbance sway angle 0; is greater than the minimum disturbance sway angle, that is, the value of the disturbance sway angle 0; exceeds the allowable range, then both the sway generated by the lifting hook itself when lifting the weight and the sway of the lifting hook caused by external disturbance need to be ameliorated. Therefore, proceed to S610, S620 and S630.

S610: controlling, by the anti-sway controller, the driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A=A,. The anti-sway controller converts the anti-sway acceleration pulse A=A, into an electrical signal and transmits the electrical signal to the inverter on the crane or the trolley. The inverter controls the driving motor of the crane or the trolley in operation, so that the motor of the crane or the trolley outputs corresponding torque for operation, to reduce sway of the lifting hook.

The starting acceleration pulse Aj and the anti-driving-sway acceleration pulse A; are applied with a difference in timing of KT,+T,/2, where K is a positive integer equal to or greater than Zero.

S620: calculating, by the anti-sway controller, the first anti-disturbance-sway acceleration LU502155 pulse A, based on the disturbance sway angle 64. As shown in Figs. 2, 4 and 5, t; is a certain instant later than ty during the acceleration phase, in s. S620 includes specifically the following calculation steps. S621: calculating the first disturbance acceleration a, according to a =10;+ g0, S622: determining the first disturbance acceleration pulse A, and the first anti-disturbance- sway acceleration pulse A; based on the first disturbance acceleration a,. The first disturbance acceleration pulse Ay is derived from the first disturbance acceleration a,. The specific calculation process belongs to prior art and shall not be described in detail here. 1; is the measured rope length in m;6; is the first disturbance sway angle; g is the acceleration of gravity in N/Kg and X is the second derivative of the first disturbance sway angle. The first anti-disturbance-sway acceleration pulse A, is calculated according to | ON (#7 A A, =exp| +-——— |* 4,

JS , where T, is the first sway period in s; 6 is the first damping coefficient valued in the range of 0 to 1; and “1 is the first frequency in rad/s. The value of the first damping coefficient 6 is set depending on the specific operation conditions during the acceleration phase and 1, S630: controlling, by the anti-sway controller, the driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A=A,. The anti-sway controller converts the anti-sway acceleration pulse A=A, into an electrical signal and transmits the electrical signal to the inverter on the crane or the trolley. The inverter controls the driving motor of the crane or the trolley in operation, so that the motor of the crane or the trolley outputs corresponding torque for operation to reduce sway of the lifting hook. Preferably, the first disturbance acceleration pulse A; and the first anti-disturbance-sway acceleration pulse A, are applied with a difference in timing of KT,+T,/2, where K is a positive integer equal to or greater than zero. It is appreciated that the anti-driving-sway acceleration pulse A; is applied later in timing than the driving sway produced upon the start of the crane or the trolley by KT,+Ty/2, and the first anti-disturbance-sway acceleration pulse A; is applied in timing later than the external disturbance by KT,+T,/2. A first anti-disturbance-sway acceleration pulse A, is applied with a difference in timing of

KT,+T,/2. That is, the first anti-disturbance-sway acceleration pulse A; is applied at a time LU502155 point where the lifting hook has the maximum sway amplitude, which is the best time point for application of the first anti-disturbance-sway acceleration pulse A,. Therefore, the sway of the lifting hook caused by external disturbance is ameliorated in a fastest and most effective way.

It is appreciated that both the sway generated by the lifting hook itself when lifting the weight and the sway of the lifting hook caused by external interference can be ameliorated by the steps described above, so that the value of the driving sway angle of the lifting hook when lifting the weight can be controlled in the allowable range.

Meanwhile, the anti-driving-sway acceleration pulse A, and the first anti-disturbance-sway acceleration pulse A; are calculated respectively, so that the inherent sway and the sway due to external disturbance can be respectively controlled accurately, thereby improving the control accuracy, ensuring the use security of the bridge crane, facilitating determination of the degree of influence of the external disturbance to the bridge crane, and consequently facilitating improvement in operation environment of the bridge crane.

At this time, the anti-sway controller accomplishes control over sway caused by the driving sway angle 6, and the disturbance sway angle 0; during the acceleration phase, so that the crane or the trolley enters the uniform-velocity operation phase in which the lifting hook is in stable operation.

However, the external environment interferes with the normal operation of the bridge crane at uncertain time points and causes sway of the lifting hook.

The sway angle sensor detects the sway angle of the lifting hook in real time and the following steps are performed.

S700: bringing the crane or the trolley into the uniform-velocity phase, in which the sway angle sensor measures the second actual sway angle 64, determining whether the second actual sway angle 0, is greater than the minimum disturbance sway angle, and if yes, proceeding to S800. Specifically, the anti-sway controller determines whether the second actual sway angle 6, is greater than the minimum disturbance sway angle.

If the second actual sway angle 64 is less than the limit value of the minimum sway angle, then the bridge crane operates stably.

If the second actual sway angle 0, is greater than the limit value of the minimum sway angle, then the sway of the lifting hook caused by external disturbance needs to be ameliorated.

Then proceed to S800. S800: calculating the second anti-disturbance-sway acceleration pulse Aj; based on the second actual sway angle 04. As shown in Figs 3 and 6, where t, is any instant in the uniform-velocity phase in s, S800 includes specifically the following steps.

S810: determining the second sway period T, of the lifting hook based on the second actual sway angle 64. LU502155 S820: calculating the actual rope length 1, according to L= 271, / 8 S830: calculating the second disturbance acceleration a, based on the actual rope length 1,. Specifically, the second disturbance acceleration a, is calculated according to a =L0j+8 0, where | is the actual rope length in m; 04 is the second actual sway angle; g is the acceleration of gravity in N/Kg; and 0; is the second derivative of the second actual sway angle.

S840: determining the second disturbance acceleration pulse As and the second anti- disturbance-sway acceleration pulse A; based on the second disturbance acceleration a,, where T, is the second sway period in s; I, is the actual rope length in m; and g is the acceleration of gravity in N/Kg.

The second disturbance acceleration pulse As is derived from the second disturbance acceleration az.

The specific calculation process belongs to prior art and shall not be described in detail here.

The second anti-disturbance-sway acceleration pulse A; is calculated according to | ¢,m, (47, el A; =exp| +-——— |* A, 4 | 1-6,

, where T, is the second sway period in s; © is the second damping coefficient valued in the range of 0 to 1; and 2 is the second frequency in rad/s.

= 1 condition during the uniform-velocity phase, and ’ A, . S900: controlling, by the anti-sway controller, the driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A, where A=A;. The anti-sway controller converts the second anti-disturbance-sway acceleration pulse A; into an electrical signal and transmits the electrical signal to the inverter on the crane or the trolley.

The inverter controls the driving motor of the crane or the trolley in operation, so that the motor of the crane or the trolley outputs corresponding torque for operation to reduce sway of the lifting hook.

Preferably, the second disturbance acceleration pulse As and the second anti-disturbance-sway acceleration pulse A; are applied with a difference in timing of NT,+Ty/2, N is a positive integer equal to or greater than zero.

It is appreciated that the second anti-disturbance-sway acceleration pulse Aj is applied later in timing than the external disturbance by NT,+T,/2. A second anti-disturbance-sway acceleration pulse Az is applied at the instant NT,+T,/2. That is, the second anti-disturbance-sway acceleration pulse Aj is applied at a time point where the LU502155 lifting hook has the maximum sway amplitude, which is the best time point for application of the second anti-disturbance-sway acceleration pulse Az.

Therefore, the sway of the lifting hook is ameliorated in a fastest and most effective way.

As such, during the uniform-velocity phase, control over the sway of the lifting hook caused by external environment is accomplished for once.

S1000: S700 to S900 are repeated.

Through repetition of S700 to S900, it is ensured that in the case where the external environment interferes with normal operation of the bridge crane at uncertain time points, the anti-sway controller controls the driving motor of the crane or the trolley in operation in real time based on the second actual sway angle 64 to reduce the sway of the lifting hook due to external disturbance to the allowable range, so as to enable closed-loop control over sway of the bucket with high control accuracy, thereby ensuring stable operation of the lifting hook , increasing operation efficiency of the crane or the trolley and improving use security of the bridge crane.

In this embodiment, the anti-sway control method further includes the deceleration phase and the stop of the crane subsequent to the uniform-velocity phase, and the control method for entrance into the deceleration phase and the stop of the crane is the same as the control method for the start and entrance into the acceleration phase and shall not be described in detail here.

In a bridge crane adopting the anti-sway control method described above, the anti-sway controller can control sway of the lifting hook in real time based on the measurement data detected by the sway angle sensor and control disturbance to the bridge crane during operation caused by the external environment at uncertain time points, so as to enable closed-loop control over sway of the lifting hook during operation of the bridge crane, thereby ensuring stable operation of the lifting hook, increasing operation efficiency of the crane or the trolley and improving use security of the bridge crane.

Obviously, the above-mentioned embodiments of the present invention are merely examples intended for clear illustration of the present invention and not limitation on the implementations of the present invention.

It is obvious to those skilled in the art that various changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention.

It is unnecessary and impossible to exhaust all the implementations here.

Any modification, equivalent substitution and improvement within the spirit and principle of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

WHAT IS CLAIMED IS: LU502155

1. An anti-sway control method for controlling sway of a lifting hook in a bridge crane during an acceleration phase and a uniform-velocity phase, the bridge crane including an anti-sway controller, a crane and a trolley in transmission connection with the crane, the lifting hook being in transmission connection with the trolley, the crane and the trolley both being provided with a sway angle sensor, the anti-sway controller being used for applying an anti-sway acceleration pulse À to the crane or the trolley, wherein the method comprises steps of: S100: starting the crane or the trolley based on a starting acceleration ao, and determining, by the anti-sway controller, a starting acceleration pulse Ag and an anti-driving-sway acceleration pulse A, based on the starting acceleration ag; S200: calculating a theoretical driving sway angle 6, of the lifting hook based on the starting acceleration pulse Ay; S300: measuring, by the sway angle sensor, a first actual sway angle 6, of the lifting hook, and calculating a disturbance sway angle 03 based on the theoretical driving sway angle 6, and the first actual sway angle 65; S400: determining whether the disturbance sway angle 0; is greater than a minimum disturbance sway angle, and if so, proceeding to S500, otherwise proceeding in sequence to S610, S620 and S630; S500: controlling, by the anti-sway controller, a driving motor of the crane or the trolley in operation based on the anti-sway acceleration pulse A, where A=A;; S610: controlling, by the anti-sway controller, the driving motor of the crane or the trolley to operate based on the anti-sway acceleration pulse A, where A=A 1; S620: calculating, by the anti-sway controller, a first anti-disturbance-sway acceleration pulse A, based on the disturbance sway angle 64; S630: controlling, by the anti-sway controller, the driving motor of the crane or the trolley to operate based on the anti-sway acceleration pulse A, where A=A;; S700: bringing the crane or the trolley into the uniform-velocity phase, in which the sway angle sensor measures a second actual sway angle 6,4, determining whether the second actual sway angle 0, is greater than the minimum disturbance sway angle, and if so, proceeding to S800; S800: calculating a second anti-disturbance-sway acceleration pulse Aj based on the second actual sway angle 04; S900: controlling, by the anti-sway controller, the driving motor of the crane or the trolley to operate based on the anti-sway acceleration pulse A, where A=A3; and S1000: repeating S700 to S900.

2. The anti-sway control method of claim 1, wherein a reel is provided on the trolley, the lifting LU502155 hook and the reel are in transmission connection with each other by a lifting rope, the reel is provided with a sensor for detecting the measured rope length |, of the lifting rope, and the first sway period T; of the lifting hook during the acceleration phase is calculated according to h=24/h/8 , where Ty is the first sway period in s; I; is the measured rope length in m, and g is the acceleration of gravity in N/Kg.

3. The anti-sway control method of claim 2, wherein the anti-driving-sway acceleration pulse Gon wr +1 | A =exp| +-—— |* 4, J1-67 A, is calculated according to , the starting acceleration pulse Ay and the anti-driving-sway acceleration pulse A; are applied with a difference in timing of KTy,+T,/2, where Ty is the first sway period in s; 6 is the first damping coefficient in the range of O to 1; “I is the first frequency in rad/s; and K is a positive integer equal to or greater than Zero.

4. The anti-sway control method of claim 2, wherein the step S620 comprises steps of: S621: calculating a first disturbance acceleration a, according to a = ho; + 80, ; and S622: determining a first disturbance acceleration pulse A4 and the first anti-disturbance-sway acceleration pulse A, based on the first disturbance acceleration a,, where |, is the measured rope length in m; 65 is the first disturbance sway angle; g is the acceleration of gravity in N/Kg and 0, is the second derivative of the first disturbance sway angle.

5. The anti-sway control method of claim 4, wherein the first anti-disturbance-sway co [+5 ) A, =exp| —————= |*A, J1-¢&; acceleration pulse A; is calculated according to and the first disturbance acceleration pulse A, and the first anti-disturbance-sway acceleration pulse A, are applied with a difference in timing of KT,+T,/2, where T, is the first sway period in s; Gi is the first damping coefficient valued in the range of O to 1; O1 is the first frequency in rad/s; and K 1s a positive integer equal to or greater than zero.

6. The anti-sway control method of claim 1, wherein the step S800 comprises:

S810: determining a second sway period T; of the lifting hook based on the second actual sway LU502155 angle 04; S820: calculating an actual rope length 1, based on N, = 27/8 ; S830: calculating a second disturbance acceleration a, based on the actual rope length 1,; and S840: determining a second disturbance acceleration pulse As and the second anti-disturbance- sway acceleration pulse A; based on the second disturbance acceleration a,, where T, is the second sway period in s; 1, is the actual rope length in m; and g is the acceleration of gravity in N/Kg.

7. The anti-sway control method of claim 6, wherein the second anti-disturbance-sway

AUS A, = exp -— — —— |* 4, J1-¢) acceleration pulse Az is calculated according to , and the second disturbance acceleration pulse As and the second anti-disturbance-sway acceleration pulse Aj are applied with a difference in timing of NT,+T,/2, where T; is the second sway period in s; © is the second damping coefficient valued in the range of 0 to 1; ?2 is the second frequency in rad/s; and N is a positive integer equal to or greater than zero.

8. The anti-sway control method of claim 6, wherein the second disturbance acceleration az is calculated according to a =hoi+g 0. where 1, is the actual rope length in m; 04 is the second actual sway angle; g is the acceleration of gravity in N/Kg; and 0; is the second derivative of the second actual sway angle.

9. The anti-sway control method of claim 1, wherein the step S500 comprises step of: converting, by the anti-sway controller, the anti-driving-sway acceleration pulse À; into an electrical signal and transmitting it to an inverter on the crane or the trolley that controls the driving motor of the crane or the trolley in operation.

10. À bridge crane adopting the anti-sway control method of any of claims 1-9.