A method, recording medium and system for overload protection of gate hoist

Abstract

The present invention belongs to the technical field of water conservancy engineering, and particularly relates to a method for overload protection of a gate hoist, wherein the maximum torque of the gate hoist is determined according to the water level difference and the maximum operating current is calculated based on the torque, and the gate hoist is prevented from being overloaded by setting a current threshold. The present invention also provides a non-transient readable recording medium storing a program of the method and a system containing the medium, and the program can be called by a processing circuit to execute the above method.

Description

Technical Field

[0001] The invention belongs to the technical field of water conservancy engineering, and discloses a method for overload protection of a gate hoist, a recording medium storing a program capable of executing the method, and a system. Background Art

[0002] In water conservancy projects, the gate hoist is an important equipment for controlling the ecological environment of the reservoir and regulating water resources. It is an important infrastructure for the country's agriculture, industry and other construction. The gate hoist must be opened by relevant professionals. If the gate is opened at will and the overload system protection measures are not in place, the gate will be damaged, which will cause major water conservancy disasters.

[0003] There are two main overload protection modes for gate hoists. The first is the fuse protection mode, that is, a fuse is connected in series in the motor power supply circuit. When overloaded, the line current increases, causing the fuse temperature to rise. Using the thermal melting effect, the fuse automatically melts at high temperature and cuts off the current, which plays an overload protection role. The second is the circuit breaker protection mode. In the normal working mode, the current passes through the static contact-moving contact-coil-bimetallic strip of the circuit breaker. When the current exceeds the rated current carrying capacity, the line is overloaded and heated, and the bimetallic strip is deformed by heat, triggering the tripping mechanism to disconnect the line and achieve overload protection. These two control modes are relatively simple to implement, but there are obvious disadvantages. Both use the thermal effect principle of current. The fuse melt is not sensitive to overload, and when a slight overload occurs, the fuse takes a long time to melt, or even does not melt, resulting in equipment damage, and the fuse cannot be restored after melting; as a switching device, the circuit breaker is generally used for overload protection. Long delay time cannot be dynamically adjusted. When a slight overload occurs, the circuit breaker will not trip immediately.

[0004] If the current is controlled, the water level difference on both sides of the reservoir gate will usually change, which causes the current to change. How should the threshold be set? If it is set too high, it will not provide protection when overload occurs. If it is set too low, when occasional jamming causes a peak current exceeding the threshold, it will affect the normal opening and closing of the valve. Therefore, how to solve the overload problem of the reservoir gate hoist has always been a problem that has troubled technicians in the field of water conservancy projects. Summary of the invention

[0005] In view of the above problems, the present invention provides a method for overload protection of a gate hoist, which specifically comprises the following steps:

[0006] S1. Detect the current value corresponding to the torque when the hoist is running when there is no water level difference on both sides of the gate through the current transformer and transmit it to the PLC;

[0007] S2. When there is no water level difference on both sides of the gate, the gate hoist is repeatedly opened and closed for many times, and the maximum value after filtering and smoothing the current value is used as the reference current value To for the gate hoist action;

[0008] According to the highest water level difference on both sides of the gate and the torque current change principle during actual operation on site, the maximum value of the current value is calculated as the maximum load current value Tmax of the gate hoist, and the ratio n of the maximum load current value Tmax to the reference current value To is calculated;

[0009] S3. In automatic mode, the PLC controls the gate hoist to open and close the gate, and detects the operating current value of the gate hoist in real time, and obtains the actual torque current value Tact after filtering;

[0010] When the ratio of the actual torque current value Tact to the reference current value To reaches 90% of the ratio n or the limit protection switch is triggered, the number of times is recorded and the program is terminated after a delay of 5-10s;

[0011] S4. Repeat step S3 until the number reaches 3, the system determines that the gate has been opened and closed, and returns a photo of the gate status taken on site;

[0012] S5. If the gate status photo shows that the gate is not actually opened or closed, manual intervention is performed to inspect the gate equipment and adjust the threshold of the ratio n.

[0013] Since the above technical solution measures the operating current of the gate hoist, it avoids the interference of the starting current on the data; the threshold is set by proportion, which avoids the embarrassing situation that the system stops the gate hoist when 90% Tact < To; when the overload protection condition is reached within 3 times, the gate hoist can continue to run slightly for 5-10s to avoid occasional jamming causing the gate hoist to stop incorrectly, and the overload situation after restarting.

[0014] Preferably, during the delay period in step S3, the speed of the gate hoist is reduced to 80% of the set speed.

[0015] In this way, even if it is really overloaded, it can be alleviated by reducing the speed and power output. The technical means to reduce the speed can be to use a variable frequency motor, or to change the opening and closing speed of the valve by matching the speed ratio through fork shifting.

[0016] In summary, the technical solution of the present application realizes timely overload protection during the operation of the gate hoist when there is a changing water level difference on both sides of the gate through reasonable control of the operating current threshold of the gate hoist.

[0017] Another solution of the present invention is to provide a non-transitory readable recording medium for storing one or more programs including a plurality of instructions. When the instructions are executed, the processing circuit will execute the above-mentioned method for overload protection of the hoist.

[0018] Another embodiment of the present invention is to provide a system for overload protection of a gate hoist, comprising a processing circuit and a memory electrically coupled thereto, wherein the memory is configured to store at least one program, wherein the program includes a plurality of instructions, and the processing circuit runs the program to execute the above-mentioned method for overload protection of the gate hoist. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the operating current threshold control of the gate hoist in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be described below in conjunction with the drawings in the embodiments of the present invention. The described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making innovative efforts are within the scope of protection of the present invention.

[0021] The gate hoist is installed at an altitude of 270m in the reservoir and is used to operate the reservoir gate. The operating conditions are dynamic underwater gate and static water gate opening. It is configured with one gate and one machine. It is equipped with a 55KW motor and a reduction box mechanism with adjustable gear ratio, and its operation is controlled by PLC.

[0022] The current transformer detects the current value corresponding to the torque when the gate hoist is running when there is no water level difference on both sides of the gate and transmits it to the PLC; the gate hoist is repeatedly opened and closed when there is no water level difference on both sides of the gate, and the maximum value after filtering and smoothing the current value is used as the reference current value To=30A for the gate hoist action;

[0023] According to the highest water level difference on both sides of the gate and the torque current change principle during actual operation on site, the maximum value of the current value is calculated to be the maximum load current value of the gate hoist 90A, and the ratio of the maximum load current value Tmax to the reference current value To is calculated as n=3;

[0024] In automatic mode, the PLC controls the gate hoist to open and close the gate, and detects the operating current value of the gate hoist in real time, and obtains the actual torque current value Tact after filtering;

[0025] When the ratio of the actual torque current value Tact to the reference current value To reaches 2.7, the number of times is recorded and the program is terminated after a delay of 5-10 seconds, during which the gate operation speed is adjusted to 80% of the original speed.

[0026] Repeat the above steps until the number reaches 3, the system determines that the gate has been opened and closed, and sends back the gate status photo taken on site;

[0027] If the gate status photo shows that the gate is not actually opened or closed, manual intervention is performed to inspect the gate equipment and adjust the threshold of the ratio n.

[0028] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computers, available storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program codes.

[0029] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0030] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0031] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0032] Compiling the above method steps into a program and then storing it on a hard disk or other non-transitory storage medium constitutes the technical solution of "a non-transitory readable recording medium" of the present invention; and electrically connecting the storage medium to a computer processor, which can complete the discharge in a time sequence according to the rainfall and the turbidity of the rainwater through data processing, constitutes the technical solution of "a system for overload protection of a gate hoist" of the present invention.

[0033] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for overload protection of a gate hoist, characterized in that The following steps are also included: S1. Detect the current value corresponding to the torque when the hoist is running when there is no water level difference on both sides of the gate through the current transformer and transmit it to the PLC; S2. When there is no water level difference on both sides of the gate, the gate hoist is repeatedly opened and closed for many times, and the maximum value after filtering and smoothing the current value is used as the reference current value To for the gate hoist action; According to the highest water level difference on both sides of the gate and the torque current change principle during actual operation on site, the maximum value of the current value is calculated as the maximum load current value Tmax of the gate hoist, and the ratio n of the maximum load current value Tmax to the reference current value To is calculated; S3. In automatic mode, the PLC controls the gate hoist to open and close the gate, and detects the operating current value of the gate hoist in real time, and obtains the actual torque current value Tact after filtering; When the ratio of the actual torque current value Tact to the reference current value To reaches 90% of the ratio n or the limit protection switch is triggered, the number of times is recorded and the program is terminated after a delay of 5-10s; S4. Repeat step S3 until the number reaches 3, the system determines that the gate has been opened and closed, and returns a photo of the gate status taken on site; S5. If the gate status photo shows that the gate is not actually opened or closed, manual intervention is performed to inspect the gate equipment and adjust the threshold of the ratio n.

2. A method for overload protection of a gate hoist according to claim 1, characterized in that: During the delay period in step S3, the speed of the gate hoist is reduced to 80% of the set speed.

3. A non-transitory readable recording medium for storing one or more programs including a plurality of instructions, characterized in that: When the instruction is executed, the processing circuit will be caused to execute a method for overload protection of a gate hoist as described in any one of claims 1-2.

4. A system for overload protection of a gate hoist, comprising a processing circuit and a memory electrically coupled thereto, characterized in that: The memory configuration stores at least one program, the program includes a plurality of instructions, and the processing circuit runs the program to execute a method for overload protection of a gate hoist as described in any one of claims 1-2.

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