System and control method for automatically controlling coal feeding through accurate material level of raw coal bunker in thermal power plant

Abstract

The invention relates to a system for automatically controlling coal feeding through the precise material level of a raw coal bunker in a thermal power plant. The system comprises a plurality of raw coal bunkers, a millimeter wave imaging radar material level meter, a coal plough, a coal conveying belt and a control system. The millimeter wave imaging radar level gauges are mounted at the top of each raw coal bunker and are used for accurately measuring the volume and height of materials in the corresponding raw coal bunker; the coal plough is arranged above each raw coal bunker and is used for feeding coal to the corresponding raw coal bunker under the control of the control system; the coal conveying belt is used for conveying raw coal, and is started according to a reverse coal flow sequence and stopped along the coal flow; and the control system is in signal data connection with the millimeter wave imaging radar level gage, the coal plough and the coal conveying belt, and is used for comprehensively judging and processing data and controlling the running states of the coal plough and the coal conveying belt according to a judgment result. Automatic coal feeding control over the raw coal bunker of the thermal power plant is effectively achieved, the reliability and stability are guaranteed, and a large amount of labor can be saved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of thermal power generation, and particularly relates to a system and a control method for automatically controlling coal feeding of a thermal power plant by using precise material level of a raw coal bunker. BACKGROUND

[0002] In the production and operation process of a thermal power plant, the control of coal feeding of a raw coal bunker is an important link for ensuring stable operation of a unit. At present, the traditional control mode of coal feeding of a raw coal bunker has many drawbacks. In terms of material level measurement, commonly used devices such as ultrasonic level meters and weight-type level meters are affected by the complex environment in the raw coal bunker, such as dust and irregular material accumulation shape, and thus it is difficult to accurately measure the real material state in the raw coal bunker, resulting in large measurement data error and making the data unreliable as a basis for automatic control of coal feeding of the raw coal bunker.

[0003] In terms of control mode, manual observation and operation are mostly relied on, and when the material level of the raw coal bunker reaches a certain value, manual control is performed on the operation of a coal plow and the start and stop of a coal conveying belt. This mode not only requires a large amount of labor, but also has a lagging reaction, and thus problems such as emptying of the raw coal bunker due to untimely coal feeding or material overflow due to excessive coal feeding are likely to occur, which seriously affects the normal production and operation of the thermal power plant and reduces the reliability and stability of the entire coal conveying system.

[0004] Therefore, it is an urgent problem in the field of coal conveying control of a thermal power plant to develop a system and a method capable of automatically controlling coal feeding by precisely measuring the material level of a raw coal bunker. SUMMARY

[0005] The present application aims to provide a system and a control method for automatically controlling coal feeding of a thermal power plant by using precise material level of a raw coal bunker, so as to solve the problems of inaccurate material level measurement, reliance on manual operation, large labor consumption, low system reliability and stability in the control of coal feeding of a raw coal bunker of an existing thermal power plant.

[0006] The present application provides a system for automatically controlling coal feeding of a thermal power plant by using precise material level of a raw coal bunker, comprising a plurality of raw coal bunkers, a millimeter wave imaging radar level meter, a coal plow, a coal conveying belt and a control system.

[0007] The millimeter wave imaging radar level meter is installed at the top of each raw coal bunker and is used to accurately measure the volume and height of the material in the corresponding raw coal bunker and transmit the measured material data to the control system.

[0008] The coal plow is arranged above each raw coal bunker and cooperates with the coal conveying belt to feed coal into the corresponding raw coal bunker under the control of the control system.

[0009] The coal conveying belt is used to convey raw coal, and its operating state is controlled by the control system and is started in the reverse coal flow order and stopped in the coal flow order.

[0010] The control system is connected with the millimeter wave imaging radar material level meter, the coal plow and the coal conveying belt in signal data, for receiving the material data transmitted by the millimeter wave imaging radar material level meter, comprehensively judging and processing the data, and controlling the running state of the coal plow and the coal conveying belt according to the judgment result.

[0011] Further, the millimeter wave imaging radar material level meter comprises a fast-scan material level meter radar and an imaging radar host, the fast-scan material level meter radar is used for obtaining stockpile data through two-dimensional axial scanning, and the radar host is used for receiving the stockpile data for algorithm processing to obtain the volume and material height of the material in the coal bunker.

[0012] Further, the radar host is further used for obtaining a three-dimensional model of the material in the coal bunker through algorithm processing on the stockpile data, and performing three-dimensional model display.

[0013] Further, the control system is provided with a low limit value, a minimum limit value and an upper limit value of each raw coal bunker.

[0014] Further, the control system is used for issuing an alarm or interlocking the coal conveying belt and the coal plow when the material level of one of the raw coal bunkers reaches the limit value.

[0015] Further, the control system adopts a DCS system.

[0016] Further, the material data is transmitted to the control system in a wired communication mode.

[0017] The application further provides a control method of the system for automatically controlling coal feeding of the raw coal bunker according to the accurate material level, comprising the following steps:

[0018] Step one: the millimeter wave imaging radar material level meter measures the volume and material height of the material in each raw coal bunker in real time, and transmits the measurement data to the control system in real time;

[0019] Step two: the control system receives and processes the measurement data, and when the material level of a single raw coal bunker reaches the low limit value, the control system issues an audible and visual alarm of the low material level of the coal bunker;

[0020] Step three: when the material level of a single raw coal bunker reaches the minimum limit value, the control system interlocks the coal plow above the coal bunker to be lifted to the falling position, and interlocks the coal conveying belt to be started in the reverse coal flow order, and other related equipment is sequentially started and operated to start feeding coal to the raw coal bunker;

[0021] Step four: when the material level of the raw coal bunker reaches the upper limit value, the control system interlocks the corresponding coal plow to be lifted to stop feeding coal to the raw coal bunker;

[0022] Step five: when all the raw coal bunker level reaches the upper limit value, the control system interlocks the coal conveying belt and related equipment to stop running, and stops the whole coal charging process.

[0023] Further, the related equipment includes a vane feeder, an activated coal feeder, a slag crusher, and a furnace coal sampling machine.

[0024] By the above-mentioned scheme, the system and control method for automatically controlling coal charging by the thermal power plant using the accurate level of the raw coal bunker have the following technical effects:

[0025] 1) Accurate measurement: the millimeter wave imaging radar level meter can accurately measure the volume and height of the material in the raw coal bunker and display a three-dimensional model, effectively solving the problem of large measurement error in traditional measurement methods, and providing a reliable data basis for accurate control of coal charging.

[0026] 2) High degree of automation: the control system comprehensively judges and processes the material data of the raw coal bunker, realizes automatic control of the plough coal device and the running state of the coal conveying belt, and does not require manual intervention, greatly saving labor.

[0027] 3) Good reliability and stability: the system can respond in time according to the actual level of the raw coal bunker, avoiding the situation of not timely or excessive coal charging, ensuring the reliability and stability of the raw coal bunker coal charging process of the thermal power plant, and further ensuring the stable operation of the thermal power plant unit.

[0028] 4) Wide application: the system and control method are not only suitable for thermal power plants, but also can be widely applied in the fields of power, chemical industry, metallurgy and other fields with high requirements for material transmission automation reliability.

[0029] The above description is only a summary of the technical scheme of the present application, in order to more clearly understand the technical means of the present application, and the content of the specification can be implemented. The following describes the preferred embodiments of the present application in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The method flowchart of the present application;

[0031] Figure 2 The structure diagram of the millimeter wave imaging radar level meter of the present application. DETAILED DESCRIPTION

[0032] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate the present application, but not to limit the scope of the present application.

[0033] Referring to Figure 1 , Figure 2The embodiment shown provides a system for automatically controlling coal feeding of a thermal power plant by using a raw coal bunker precise level, which comprises a plurality of raw coal bunkers, a millimeter wave imaging radar material level meter, a coal plow, a coal belt, and a control system.

[0034] The millimeter wave imaging radar material level meter is installed at the top of each raw coal bunker, and is used for precisely measuring the volume and height of the material in the corresponding raw coal bunker, and transmitting the measured material data to the control system. The millimeter wave imaging radar material level meter measures the entire interior of the raw coal bunker, can accurately capture the volume and height information of the material, and transmit the data to the control system through wired communication.

[0035] The coal plow is arranged above each raw coal bunker, cooperates with the coal belt, and is used for feeding coal into the corresponding raw coal bunker under the control of the control system. The action of the coal plow is controlled by the control system, and the coal plow can realize switching between the lifted state and the fallen state.

[0036] The coal belt is used for conveying raw coal, and its running state is controlled by the control system. The coal belt is started in the reverse coal flow order and stopped in the coal flow order.

[0037] The control system is connected with the millimeter wave imaging radar material level meter, the coal plow, and the coal belt in signal data connection, is used for receiving the material data transmitted by the millimeter wave imaging radar material level meter, comprehensively judging and processing the data, and controlling the running state of the coal plow and the coal belt according to the judgment result.

[0038] In the embodiment, the millimeter wave imaging radar material level meter comprises a fast-scan material level meter radar and an imaging radar host. The fast-scan material level meter radar is used for obtaining pile data through two-dimensional axial scanning, and the radar host is used for receiving the pile data for algorithm processing to obtain the volume and height of the material in the coal bunker. In an environment with relatively large dust, the millimeter wave imaging radar is not affected by environmental factors such as rain, dust, and light, and has good imaging effect.

[0039] In the embodiment, the radar host is also used for obtaining a three-dimensional model of the material in the coal bunker by algorithm processing the pile data, and displaying the three-dimensional model.

[0040] In the embodiment, the control system is provided with a low limit value, a minimum limit value, and an upper limit value of each raw coal bunker. When the level of one of the raw coal bunkers reaches the limit value, an alarm is sent or the coal belt and the coal plow are interlocked to act.

[0041] In the embodiment, the control system adopts a DCS system, has powerful data processing and logic control capability, can receive data transmitted by the millimeter wave imaging radar material level meter in real time, analyzes and judges the data according to a logic configuration, issues an alarm signal, and issues a control instruction to the plough coal device, the coal conveying belt and related equipment.

[0042] The control method of the system for automatically controlling coal feeding of the raw coal bunker with precision comprises the following steps:

[0043] Step one: the millimeter wave imaging radar material level meter measures the material volume and the material height in each raw coal bunker in real time, and transmits the measurement data to the control system in real time;

[0044] Step two: the control system receives and processes the measurement data, and when the material level of a single raw coal bunker reaches a lower limit value, the control system issues an audible and visual alarm that the material level of the coal bunker is low;

[0045] Step three: when the material level of a single raw coal bunker reaches the lower limit value, the control system immediately issues an instruction, the control system interlocks the plough coal device above to move to the falling position, and simultaneously interlocks the coal conveying belt to start in the order opposite to the coal flow, that is, the belt driving part far away from the raw coal bunker is started first, and then the parts close to the raw coal bunker are started in turn, and then other related equipment such as the coal feeder is started to run in turn, and the process of feeding coal to the raw coal bunker starts;

[0046] Step four: during the process of feeding coal to the raw coal bunker, the millimeter wave imaging radar material level meter continuously measures the material level, and when the material level of the raw coal bunker reaches an upper limit value, the control system interlocks the corresponding plough coal device to lift up, and stops feeding coal to the raw coal bunker;

[0047] Step five: when the material levels of all raw coal bunkers reach the upper limit value, the control system interlocks the coal conveying belt and the coal feeder and other related equipment to stop running, and stops the whole process of feeding coal.

[0048] The millimeter wave imaging radar technology adopted in the application can accurately measure the material volume and the material height in the bunker, and display a three-dimensional model, can accurately measure the real material state in the raw coal bunker, effectively realizes automatic coal feeding control of the raw coal bunker of the thermal power plant, ensures the reliability and stability, and can save a large amount of labor, and has a wide application prospect in the fields of power, chemical industry, metallurgy and other fields with high requirements for material conveying automation reliability.

[0049] The above is only the preferred embodiment of the application, and is not used to limit the application, and it should be pointed out that, for ordinary skilled persons in the art, without departing from the technical principles of the application, a number of improvements and modifications can be made, and these improvements and modifications should be regarded as the protection scope of the application.

Claims

1. A system for automatically controlling coal feeding in a thermal power plant using precise coal level control in a raw coal bunker, characterized in that, This includes multiple raw coal bunkers, millimeter-wave imaging radar level gauges, coal plows, coal conveyor belts, and control systems. The millimeter-wave imaging radar level gauge is installed on the top of each raw coal bunker to accurately measure the volume and height of the material in the corresponding raw coal bunker and transmit the measured material data to the control system. The coal plow is arranged above each raw coal bunker and works in conjunction with the coal conveyor belt to feed coal to the corresponding raw coal bunker under the control of the control system. The coal conveyor belt is used to transport raw coal, and its operation is controlled by the control system. It starts in the reverse coal flow sequence and stops in the forward coal flow sequence. The control system is connected to the millimeter-wave imaging radar level gauge, the coal plow, and the coal conveyor belt via signal data connection. It is used to receive material data transmitted by the millimeter-wave imaging radar level gauge, perform comprehensive judgment and processing on the data, and control the operating status of the coal plow and the coal conveyor belt according to the judgment results.

2. The system for automatic coal feeding control using precise coal level in a thermal power plant according to claim 1, characterized in that, The millimeter-wave imaging radar level gauge includes a fast-scan level gauge radar and an imaging radar host. The fast-scan level gauge radar is used to obtain material stockpile data through two-dimensional axial scanning. The radar host is used to receive the material stockpile data and perform algorithm processing to obtain the volume and height of the material in the coal bunker.

3. A system for automatic coal feeding in a thermal power plant using precise coal bunker level control, as described in claim 2, is characterized in that... The radar host is also used to process the stockpiled data using algorithms to obtain a three-dimensional model of the materials in the coal bunker and to display the three-dimensional model.

4. A system for automatic coal feeding in a thermal power plant using precise coal bunker level control, as described in claim 3, is characterized in that... The control system sets a minimum, maximum, and maximum value for each raw coal bunker.

5. A system for automatic coal feeding in a thermal power plant using precise coal bunker level control, as described in claim 4, is characterized in that... The control system is used to issue an alarm or interlock the operation of the coal conveyor belt and coal plow when the level in one of the raw coal bunkers reaches the limit.

6. A system for automatic coal feeding control in a thermal power plant using precise coal bunker level as described in claim 5, characterized in that, The control system adopts a DCS system.

7. A system for automatic coal feeding in a thermal power plant using precise coal bunker level control, as described in claim 6, is characterized in that... The material data is transmitted to the control system via wired communication.

8. A control method for a system for precise automatic control of coal level in a raw coal bunker as described in any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1: The millimeter-wave imaging radar level gauge measures the material volume and height in each raw coal bunker in real time and transmits the measurement data to the control system in real time; Step 2: The control system receives and processes the measurement data. When the level of a single raw coal bunker reaches the low limit, the control system issues an audible and visual alarm indicating that the level of the coal bunker is low. Step 3: When the level of a single raw coal bunker reaches the minimum limit, the control system interlocks the plow above it to move to the lower position, and at the same time, the coal conveyor belt is started in the reverse coal flow sequence, and other related equipment starts to run in succession to start feeding coal into the raw coal bunker. Step 4: When the raw coal bunker level reaches the upper limit, the control system interlocks and lifts the corresponding coal plow, stopping the feeding of coal into the raw coal bunker; Step 5: When the level of all raw coal bunkers reaches the upper limit, the control system interlocks the coal conveyor belt and related equipment to stop, thus stopping the entire coal loading process.

9. The control method according to claim 8, characterized in that, The relevant equipment includes an impeller feeder, an activated feeder, a slag crusher, and a coal sampler for furnace entry.

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