阅读说明：本技术 一种给水自动控制的方法、装置、及存储介质 (Method, device and storage medium for automatically controlling water supply ) 是由 王浩 张丽新 田晓男 李志华 李翠娟 于 2021-07-16 设计创作，主要内容包括：本公开提供了一种给水自动控制的方法及装置。包括：根据采集的机组启动过程中的参数信号,以及接收的再循环流量设定值,生成第一运算结果以及生成再循环泵出口调节门实时开度调节指令。控制旁路给水调节门,根据给水流量设定值与给水流量实际值偏差进行比例积分运算,生成第二运算结果以及生成旁路给水调节门开度调节指令。控制给水泵转速,在满足预定条件时,控制所述给水泵切换为自动运行状态。本公开实施例提供的技术方案,改变了常规启动过程需人工进行多参数监视、多设备操作的高强度工作方式,避免了人工监视不到位和设备操作失误的风险。(The present disclosure provides a method and apparatus for automatically controlling water supply. The method comprises the following steps: and generating a first operation result and a real-time opening adjusting instruction of an outlet adjusting door of the recirculation pump according to the acquired parameter signals in the starting process of the unit and the received recirculation flow set value. And controlling the bypass water supply regulating valve, performing proportional integral operation according to the deviation of the set value and the actual value of the water supply flow, generating a second operation result and generating an opening regulating instruction of the bypass water supply regulating valve. And controlling the rotating speed of the water feeding pump, and controlling the water feeding pump to be switched into an automatic running state when a preset condition is met. The technical scheme provided by the embodiment of the disclosure changes the high-intensity working mode that multi-parameter monitoring and multi-equipment operation are required manually in the conventional starting process, and avoids the risks of manual monitoring and equipment misoperation.)

1. An automatic water supply control method is used in a thermal power generating unit with a single steam-driven water supply pump for an ultra-supercritical once-through boiler, and is characterized by comprising the following steps:

acquiring parameter signals acquired by a signal acquisition module in a unit starting process, and receiving a recirculation flow set value through a human-computer interface module, wherein the parameter signals comprise: actual values of recirculation flow and feedwater flow;

carrying out proportional integral operation according to the deviation of a recirculation flow set value and the recirculation flow actual value to generate a first operation result, and generating a real-time opening degree adjusting instruction of an outlet adjusting valve of the recirculation pump according to the first operation result;

controlling a bypass water supply adjusting valve to keep a preset opening degree until the water supply flow reaches a first switching condition, performing proportional integral operation according to the deviation between a water supply flow set value and a water supply flow actual value to generate a second operation result, and generating a bypass water supply adjusting valve opening degree adjusting instruction according to the second operation result;

and controlling the water feeding pump to operate at a default rotating speed value until the opening of the bypass water feeding adjusting valve reaches a second switching condition, and controlling the water feeding pump to be switched to an automatic operation state after the rotating speed of the water feeding pump is switched to a target rotating speed value for a set time period.

2. The method of claim 1, wherein: the parameter signals in the starting process can also comprise the liquid level of a water storage tank, the fuel quantity, the opening of a recirculation valve, the opening of a bypass feed water adjusting valve, the rotating speed value of a feed pump and the automatic output value of the feed pump;

the recirculation flow set value is formed by adding a first manual corrected value, a coal supply signal 4-order function value and a water storage tank liquid level deviation value, the first manual corrected value is a corrected value input by operating personnel during cold and hot cleaning, the coal supply signal 4-order function value can overcome system disturbance caused by water supply evaporation during boiler ignition and coal amount increase, the water storage tank liquid level deviation value is used for rapidly adjusting the flow when the working condition of a water supply system is unstable, the liquid level is stabilized by matching with 360 valves, and the operation safety of the recirculation pump is guaranteed.

3. The method of claim 1, wherein: the first switching condition is that the water supply flow is more than 850t/h and is delayed for 10 minutes; and the second switching condition is that the opening of the bypass feedwater regulating valve is larger than 70% and is delayed for 1 minute.

4. The method of claim 3, wherein: the water supply flow set value is formed by adding an output value of a flow switcher and a second manual correction value, the default output value of the flow switcher is 900t/h, after a main bypass switching signal is received, the output value of the flow switcher is switched to 1200t/h, and then the second manual correction value is superposed, so that the opening of a bypass water supply adjusting valve reaches more than 70%;

after the water feeding pump is automatically put into operation, the opening degree of the bypass water feeding adjusting door is controlled to be adjusted to 100% opening degree calculated through an inertia link, and a main water feeding adjusting door full-opening instruction is triggered through a bypass water feeding adjusting door full-opening signal to finish automatic switching operation of a main water feeding bypass.

5. The utility model provides a feedwater automatic control device for in ultra supercritical once-through boiler joins in marriage single steam-driven feed pump thermal power generating unit, the device includes man-machine interface module, signal acquisition module, core control ware and instruction output module, its characterized in that:

the human-computer interface module is used for receiving an operation instruction input by an operator, and the operator inputs a control signal through a button displayed by the human-computer interface module and receives a recirculation flow set value;

the signal acquisition module is used for acquiring parameter signals in the starting process of the unit, and the parameter signals comprise: actual values of recirculation flow and feedwater flow;

the core controller comprises a recirculation pump outlet regulating gate controller, a water supply regulating gate controller and a water supply pump rotating speed instruction switcher,

the controller of the outlet adjusting door of the recirculation pump is used for carrying out proportional integral operation according to the deviation between the set value of the recirculation flow and the actual value of the recirculation flow to generate a first operation result and generating a real-time opening adjusting instruction of the outlet adjusting door of the recirculation pump according to the first operation result;

the water supply regulating gate controller is composed of an instruction switcher and a proportional-integral arithmetic unit, wherein the instruction switcher controls the bypass water supply regulating gate to keep a preset opening degree, and when the water supply flow reaches a first switching condition, the bypass water supply regulating gate is switched to the proportional-integral arithmetic unit, the proportional-integral arithmetic unit carries out proportional-integral arithmetic operation according to the deviation between the water supply flow set value and the water supply flow actual value, a second arithmetic result is generated, and a bypass water supply regulating gate opening degree regulating instruction is generated according to the second arithmetic result;

the water feeding pump rotating speed instruction switcher is used for controlling the water feeding pump to operate at a default rotating speed value, and controlling the water feeding pump to be switched to an automatic operation state after the rotating speed of the water feeding pump is switched to a target rotating speed value and the water feeding pump is operated for a set time length when the opening of the bypass water feeding adjusting valve reaches a second switching condition;

and the instruction output module is used for outputting a control instruction.

6. The apparatus of claim 5, wherein: the parameter signals in the starting process further comprise a water storage tank liquid level, a fuel quantity, a recirculation valve opening, a bypass water supply regulating opening, a water supply pump rotating speed value and a water supply pump automatic output value;

the recirculation flow set value is formed by adding a first manual corrected value, a coal supply signal 4-order function value and a water storage tank liquid level deviation value, the first manual corrected value is a corrected value input by operating personnel during cold and hot cleaning, the coal supply signal 4-order function value can overcome system disturbance caused by water supply evaporation during boiler ignition and coal amount increase, the water storage tank liquid level deviation value is used for rapidly adjusting the flow when the working condition of a water supply system is unstable, the liquid level is stabilized by matching with 360 valves, and the operation safety of the recirculation pump is guaranteed.

7. The apparatus of claim 6, wherein: the first switching condition is that the water supply flow is more than 850t/h and is delayed for 10 minutes; and the second switching condition is that the opening of the bypass feedwater regulating valve is larger than 70% and is delayed for 1 minute.

8. The apparatus of claim 7, wherein: the proportional integral arithmetic unit performs proportional integral operation according to the deviation of a set value of the water supply flow and an actual value of the water supply flow and then outputs an opening instruction of the bypass water supply regulating valve, wherein the set value of the water supply flow is formed by adding an output value of a flow switcher and a second manual correction value, the default output value of the flow switcher is 900t/h, after a main bypass switching signal is received, the output value of the flow switcher is switched to 1200t/h, and the second manual correction value is superposed, so that the opening of the bypass water supply regulating valve is more than 70%;

after the water feeding pump is automatically put into operation, the opening degree of the bypass water feeding adjusting door is controlled to be adjusted to 100% opening degree calculated through an inertia link, and a main water feeding adjusting door full-opening instruction is triggered through a bypass water feeding adjusting door full-opening signal to finish automatic switching operation of a main water feeding bypass.

9. The utility model provides a core control ware for feedwater automatic control for in ultra supercritical once-through boiler joins in marriage single steam feed pump thermal power generating unit, its characterized in that: the core controller comprises a recirculation pump outlet regulating gate controller, a water supply regulating gate controller and a water supply pump rotating speed instruction switcher,

the controller of the outlet adjusting door of the recirculation pump is used for carrying out proportional integral operation according to the deviation between the set value of the recirculation flow and the actual value of the recirculation flow to generate a first operation result and generating a real-time opening adjusting instruction of the outlet adjusting door of the recirculation pump according to the first operation result;

the water supply regulating gate controller is composed of an instruction switcher and a proportional-integral arithmetic unit, wherein the instruction switcher controls the bypass water supply regulating gate to keep a preset opening degree, and the bypass water supply regulating gate is switched to the proportional-integral arithmetic unit after a first switching condition is met, the proportional-integral arithmetic unit performs proportional-integral arithmetic operation according to the deviation between the set value of the water supply flow and the actual value of the water supply flow to generate a second arithmetic result, and a bypass water supply regulating gate opening degree regulating instruction is generated according to the second arithmetic result;

and the water feeding pump rotating speed instruction switcher controls the water feeding pump to operate at a default rotating speed value until the opening degree of the bypass water feeding adjusting valve reaches a second switching condition, and controls the water feeding pump to be switched to an automatic operation state after the rotating speed of the water feeding pump is switched to a target rotating speed value and the water feeding pump operates for a set time length.

10. An automatic water supply control device, comprising: memory, processor and computer program stored on the memory and executable on the processor, the computer program, when executed by the processor, implementing the steps of the water supply automatic control method according to any one of claims 1 to 4.

Technical Field

The disclosure relates to the technical field of industrial automation, in particular to a water supply automatic control method and device for an ultra-supercritical thermal power generating unit in a single steam-driven water supply pump configuration and a computer readable storage medium.

Background

The water supply pump of domestic coal-fired power station is equipped with three electric pumps (mainly air-cooling machine set), two steam pumps, one electric pump, two steam pumps, one steam-one electric pump and single steam pump. In recent years, a large-capacity thermal power generating set slowly tends to a single steam pump, so that the efficiency of the pump can be improved, and the plant power consumption rate can be saved. At present, most of units for carrying out automatic water supply control research in China are two steam pumps and one electric pump, the existing application of single-steam-pump automatic water supply control is water supply control after CCS investment, and the research on water supply automatic control under a single-steam-pump configuration mode in the whole starting process, particularly in the starting stage of the units, is not carried out at present.

However, the unit starting stage is a stage in which the monitoring panel intensity of operators is the maximum and the operation frequency is the maximum, the water level of a water storage tank, the recirculation flow and the water supply flow need to be manually considered in the water supply control, particularly in the wet state temperature rising stage, at the moment, high-intensity monitoring and control operation needs to be manually carried out, and in the process that the boiler is switched from the wet state to the dry state, the operation of a water supply valve, the rotating speed of a steam pump and the coal supply quantity instruction needs to be manually and frequently carried out. Therefore, the risk of insufficient manual monitoring and operational errors of the apparatus easily occurs.

Disclosure of Invention

The embodiment of the disclosure provides a method and a device for automatically controlling water supply, which are used for solving the problem of a high-intensity working mode that multi-parameter monitoring and multi-equipment operation are required manually in the starting process, and avoiding the risks of insufficient manual monitoring and equipment misoperation.

The embodiment of the disclosure also provides a computer readable storage medium.

The embodiment of the disclosure adopts the following technical scheme:

an automatic control method for water supply is used in an ultra-supercritical once-through boiler with a single steam-driven water-feeding pump thermal power generating unit, and is characterized by comprising the following steps:

acquiring parameter signals acquired by a signal acquisition module in a unit starting process, and receiving a recirculation flow set value through a human-computer interface module, wherein the parameter signals comprise: actual values of recirculation flow and feedwater flow;

carrying out proportional integral operation according to the deviation of a recirculation flow set value and the recirculation flow actual value to generate a first operation result, and generating a real-time opening degree adjusting instruction of an outlet adjusting valve of the recirculation pump according to the first operation result;

controlling a bypass water supply adjusting valve to keep a preset opening degree until the water supply flow reaches a first switching condition, performing proportional integral operation according to the deviation between a water supply flow set value and a water supply flow actual value to generate a second operation result, and generating a bypass water supply adjusting valve opening degree adjusting instruction according to the second operation result;

and controlling the water feeding pump to operate at a default rotating speed value until the opening of the bypass water feeding adjusting valve reaches a second switching condition, and controlling the water feeding pump to be switched to an automatic operation state after the rotating speed of the water feeding pump is switched to a target rotating speed value for a set time period.

The utility model provides a feedwater automatic control device for in ultra supercritical once-through boiler joins in marriage single steam-driven feed pump thermal power generating unit, the device includes man-machine interface module, signal acquisition module, core control ware and instruction output module, its characterized in that:

the human-computer interface module is used for receiving an operation instruction input by an operator, and the operator inputs a control signal through a button displayed by the human-computer interface module and receives a recirculation flow set value;

the signal acquisition module is used for acquiring parameter signals in the starting process of the unit, and the parameter signals comprise: actual values of recirculation flow and feedwater flow;

the core controller comprises a recirculation pump outlet regulating gate controller, a water supply regulating gate controller and a water supply pump rotating speed instruction switcher,

the controller of the outlet adjusting door of the recirculation pump is used for carrying out proportional integral operation according to the deviation between the set value of the recirculation flow and the actual value of the recirculation flow to generate a first operation result and generating a real-time opening adjusting instruction of the outlet adjusting door of the recirculation pump according to the first operation result;

the water supply regulating gate controller is composed of an instruction switcher and a proportional-integral arithmetic unit, wherein the instruction switcher controls the bypass water supply regulating gate to keep a preset opening degree, and when the water supply flow reaches a first switching condition, the bypass water supply regulating gate is switched to the proportional-integral arithmetic unit, the proportional-integral arithmetic unit carries out proportional-integral arithmetic operation according to the deviation between the water supply flow set value and the water supply flow actual value, a second arithmetic result is generated, and a bypass water supply regulating gate opening degree regulating instruction is generated according to the second arithmetic result;

the water feeding pump rotating speed instruction switcher is used for controlling the water feeding pump to operate at a default rotating speed value, and controlling the water feeding pump to be switched to an automatic operation state after the rotating speed of the water feeding pump is switched to a target rotating speed value and the water feeding pump is operated for a set time length when the opening of the bypass water feeding adjusting valve reaches a second switching condition;

and the instruction output module is used for outputting a control instruction.

The utility model provides a core control ware for feedwater automatic control for in ultra supercritical once-through boiler joins in marriage single steam feed pump thermal power generating unit, its characterized in that: the core controller comprises a recirculation pump outlet adjusting door controller, a water supply adjusting door controller and a water supply pump rotating speed instruction switcher.

The controller of the outlet adjusting door of the recirculation pump is used for carrying out proportional integral operation according to the deviation between the set value of the recirculation flow and the actual value of the recirculation flow to generate a first operation result and generating a real-time opening adjusting instruction of the outlet adjusting door of the recirculation pump according to the first operation result;

the water supply regulating gate controller is composed of an instruction switcher and a proportional-integral arithmetic unit, wherein the instruction switcher controls the bypass water supply regulating gate to keep a preset opening degree, and the bypass water supply regulating gate is switched to the proportional-integral arithmetic unit after a first switching condition is met, the proportional-integral arithmetic unit performs proportional-integral arithmetic operation according to the deviation between the set value of the water supply flow and the actual value of the water supply flow to generate a second arithmetic result, and a bypass water supply regulating gate opening degree regulating instruction is generated according to the second arithmetic result;

and the water feeding pump rotating speed instruction switcher controls the water feeding pump to operate at a default rotating speed value until the opening degree of the bypass water feeding adjusting valve reaches a second switching condition, and controls the water feeding pump to be switched to an automatic operation state after the rotating speed of the water feeding pump is switched to a target rotating speed value and the water feeding pump operates for a set time length.

The embodiment of the present disclosure adopts at least one technical scheme that can achieve the following beneficial effects:

the automatic control method and the automatic controller device for the whole cold starting process of the unit are designed aiming at the ultra-supercritical once-through boiler with a single steam-driven feed pump thermal power generating unit. In the starting process of the unit, an operator controls the switching time by manually correcting the set value of the recirculation flow, the set value of the water supply flow and operating the water supply switching button according to the actual working condition, and therefore the ideal water supply control effect of the whole starting process of the unit can be achieved. The high-intensity working mode that multi-parameter monitoring and multi-equipment operation are manually carried out in the conventional starting process is changed, and the risks of manual monitoring failure and equipment misoperation are avoided.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic flow chart of an automatic water supply control method according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of an automatic water supply control device according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a core controller according to the present disclosure.

Detailed Description

To make the objects, technical solutions and advantages of the present disclosure more apparent, the following embodiments of the present disclosure will be clearly and completely described in conjunction with the accompanying drawings. It is to be understood that the described embodiments are merely a subset of the disclosed embodiments and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

The existing thermal power unit water supply equipment adopting a single steam pump mode mainly comprises: a feed pump, a main feed water gate, a feed water bypass adjustment gate, a steam-water separator, a boiler recirculation pump, and a boiler recirculation adjustment gate. The unit starting stage is roughly divided into: the method comprises the following steps of boiler cold state washing, boiler ignition, boiler hot state cleaning, wet state heating and boosting operation, turbine turning, grid connection, wet state turning to dry state (in the process, operators switch bypass feed water to main path feed water through valve operation), dry state heating and boosting to 40% load, and then CCS (continuous cooling system) is put into operation. The investment of the CCS marks the end of the train startup phase.

The process before the wet state changes to the dry state is called the wet state of the boiler, and then the dry state.

At present, no automatic water supply control logic aiming at the wet and wet-to-dry processes of the boiler exists, or the control logic cannot achieve the control effect of automatic adjustment without full adjustment tests. All processes of the unit starting are realized by manual control, and operators need to manually input an opening instruction of a valve, a rotating speed instruction or a flow instruction of a feed pump on a DCS operation computer so as to obtain the required feed water flow and the required boiler recirculation flow. Therefore, the operator should consider the operation of the feed water bypass adjusting door, the feed water pump rotating speed and the boiler recirculation adjusting door at the same time.

In order to change the high-intensity working mode that the conventional starting process needs manual multi-parameter monitoring and multi-equipment operation and avoid the risks of insufficient manual monitoring and equipment misoperation, the disclosure provides a novel water supply control method and a novel water supply control device.

After the feedwater control method is adopted, no manual operation is needed in the wet state and wet state to dry state processes of the boiler. The preset feed water flow is corrected through the feed water flow manual correction input window, and the required recirculation water flow is set through the recirculation water flow manual setting window.

The technical solutions provided by the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

Example 1

In order to solve the problem of a high-intensity working mode that multiple-parameter monitoring and multiple-equipment operation are required manually in the starting process in the prior art, the embodiment of the invention provides a method for automatically controlling water supply, which is used in an ultra-supercritical once-through boiler with a single steam-driven water-feeding pump thermal power unit, and the specific implementation flow chart of the method is shown in figure 1, and comprises the following steps:

s1, acquiring a parameter signal acquired by a signal acquisition module in a unit starting process, and receiving a recirculation flow set value through a human-computer interface module, wherein the parameter signal comprises: an actual value of recirculation flow and an actual value of feedwater flow.

The core controller acquires an actual value of water feeding flow, an actual value of recirculation flow, a liquid level of a water storage tank, a fuel amount, the opening of a recirculation valve, the opening of a bypass water feeding adjusting valve, a rotational speed signal of a steam-driven water feeding pump, an automatic output value of the water feeding pump, a set value of manual recirculation flow and a correction signal of the set value of water feeding flow received from a human-computer interface in real time through a signal acquisition module, and gives an opening instruction of the recirculation valve, an opening instruction of a water feeding bypass and a rotational speed instruction of the steam-driven water feeding pump through calculation to control various parameter indexes of a water feeding system in a good state in the whole starting process.

And S2, performing proportional integral operation according to the deviation of the recirculation flow set value and the recirculation flow actual value to generate a first operation result, and generating a real-time opening degree adjusting instruction of an outlet adjusting door of the recirculation pump according to the first operation result.

The recirculation pump outlet regulating valve controller adopts the deviation of a recirculation flow set value and an actual value to carry out proportional integral operation to obtain a real-time opening instruction of the recirculation pump outlet regulating valve, and the proportional coefficient and the integral time are obtained by a thermal control engineer through debugging by using an engineering experience method according to the working conditions of a production field. The actual value of the recirculation flow is read by the controller from the plant DCS system. The recirculation flow set value is formed by adding a first manual correction value, a coal supply signal 4-order function value and a water storage tank liquid level deviation value, the first manual correction value is used for adapting to the requirement of manually adjusting the flow according to the actual condition when in cold and hot cleaning, the coal supply function overcomes the system disturbance caused by boiler ignition and water supply evaporation when the coal amount is increased, the water storage tank liquid level deviation value is used for rapidly adjusting the flow when the system working condition is unstable, and the liquid level is stabilized by matching with a 360-valve, so that the operation safety of the recirculation pump is ensured.

And S3, controlling the bypass water supply adjusting valve to keep a preset opening degree until the water supply flow reaches a first switching condition, performing proportional integral operation according to the deviation between the set value of the water supply flow and the actual value of the water supply flow to generate a second operation result, and generating an opening degree adjusting instruction of the bypass water supply adjusting valve according to the second operation result.

And the instruction switcher of the feed water regulating door controller defaults to output an instruction of 10%, controls the bypass feed water regulating door to keep 10% of opening, and switches to the proportional-integral arithmetic unit after a first switching condition is reached, wherein the proportional-integral arithmetic unit performs proportional-integral arithmetic according to the deviation of a set value of the feed water flow and an actual value of the feed water flow and outputs an opening instruction of the bypass feed water regulating door.

The water supply regulating gate controller consists of an instruction switcher and a proportional-integral arithmetic unit, the instruction switcher defaults to output an instruction of 10 percent, so that the bypass regulating gate keeps 10 percent of opening, and the instability of the system caused by the measurement fluctuation of a pore plate under the working condition of small flow at the initial starting stage is eliminated. When the switching condition is reached (the water supply flow is more than 850t/h, the time is delayed for 10 minutes), the switching is carried out to a proportional integral arithmetic unit (a bypass water supply regulating valve opening degree instruction is output after the deviation of the water supply flow set value and the actual value is subjected to proportional integral arithmetic). The water supply flow set value is formed by adding a flow switcher and a manual correction value, the flow switcher outputs 900t/h by default, and the flow required during the starting period is met; and after the switching condition is met (the main bypass switching button is manually clicked), the switching is carried out to 1200t/h, and then manual correction is superposed to ensure that the bypass adjusting door reaches more than 70% of opening degree before the automatic switching operation of the main water supply bypass is carried out. After the water supply pump is automatically put into operation, the controller instruction switcher outputs an instruction to switch to a 100% instruction calculated through an inertia link, so that the bypass door is slowly opened to 100%, and a main water supply door full-opening instruction is triggered by a bypass door full-opening signal to finish the automatic operation of water supply main bypass switching.

And S4, controlling the water feeding pump to operate at a default rotating speed value, and controlling the water feeding pump to be switched to an automatic operation state after the rotating speed of the water feeding pump is controlled to be switched to a target rotating speed value and operate for a set time length when the opening of the bypass water feeding adjusting valve reaches a second switching condition.

Specifically, the default output water-feeding pump rotating speed value can be set to 2400rpm, whether a second switching condition is reached currently is judged, when the second switching condition is reached, the water-feeding pump rotating speed is switched to 3000rpm, and after the water-feeding pump rotating speed reaches 3000rpm and is delayed for 5 minutes, an automatic input signal is generated and triggers the water-feeding pump rotating speed instruction switcher to switch to the water-feeding pump automatic input stage.

The feed water pump rotational speed command switcher outputs 2400rpm by default. The critical range 2650-2850 rpm of a water feeding pump turbine is avoided, and the cleaning flow is not lower than 850 t/h. When the switching condition is reached (the bypass opening is larger than 70% and is delayed for 1 minute), the switching is carried out to 3000rpm, when the set value is reached and the delay is 5 minutes, the water feeding pump is put into operation automatically, and the automatic input signal triggers the instruction switcher to output and switch to the automatic output value of the conventional water feeding pump.

After the method is adopted, no manual operation is needed in the wet state and wet state to dry state processes of the boiler. The preset feed water flow is corrected through the feed water flow manual correction input window, and the required recirculation water flow is set through the recirculation water flow manual setting window.

After the conventional power plant is in a dry state, the water supply door and the bypass adjusting door of the water supply door are opened to 100 percent of opening degree, and the recycling adjusting door of the water supply pump is closed to 0 percent. The water supply flow instruction of the water supply pump is output by a DCS water supply main controller without being adjusted, and is not manually set by an operator. The controller also exits from operation after the controller is in a dry state.

Example 2

Fig. 2 shows a schematic structural diagram of an automatic feedwater control device provided by an embodiment of the present disclosure. As shown in fig. 2, the automatic water supply control device 1 includes a human-machine interface module 12, a signal acquisition module 13, a core controller 14, and a command output module 15. The automatic water supply control device is connected to the DCS system 2 of the power plant, and can read data from the DCS system 2.

The human-computer interface module 12 is configured to receive an operation instruction input by an operator, and the operator inputs a control signal through a button displayed by the human-computer interface module. The control device is used for receiving an operation instruction input by an operator, and the operator inputs a control signal through a button presented by the human-computer interface module and receives a set value of the recirculation flow. The human-computer interface presented by the human-computer interface module is used for inputting an operation instruction, and an operator can input the recirculation flow manual correction value, the feed water flow manual correction value and the main bypass switching button through an operation window of the human-computer interface and can present the recirculation flow manual correction value, the feed water flow manual correction value and the main bypass switching button on the human-computer interface through the human-computer interface module. When the main bypass is switched, a switching confirmation button is arranged on a human-computer interface, the button is lightened to operate after the conditions described in the text are met, and after a person presses the button, the controller completes the operation of a relevant valve for switching the water supply bypass to the main path. At the moment, the thermal power generating unit is already connected to the grid for power generation, and the other related systems except the system in the thermal power generating unit need to be manually confirmed to be switchable under the condition of normal operation.

And the signal acquisition module 13 is used for acquiring parameter signals in the starting process of the unit. The signal acquisition module acquires an actual water supply flow value, a water storage tank liquid level, a fuel amount, a recirculation valve opening, a bypass water supply regulating opening, a steam-driven water supply pump rotating speed signal, a water supply pump automatic output value, a manual recirculation flow set value and a water supply flow set value correction signal received from a human-computer interface in a starting process in real time, and gives a recirculation valve opening instruction, a water supply bypass opening instruction and a steam-driven water supply pump rotating speed instruction through calculation, and all parameter indexes of a water supply system in the whole starting process are controlled to be in good states.

The core controller 14 includes a recirculation pump outlet throttle controller, a feedwater throttle controller, and a feedwater pump speed command switch. The automatic control system is a core component for providing automatic control of water supply, acquires parameters of a water supply system, and gives corresponding control instructions according to a calculation result so as to control the water supply.

The instruction output module 14 is configured to output a control instruction. The instruction output module 14 outputs the control instruction obtained by the core controller to the corresponding equipment, for example, outputs the calculated opening instruction of the recirculation valve, the opening instruction of the water supply bypass and the rotation speed instruction of the steam feed water pump to the corresponding control device, and controls the opening of the valve and the rotation speed of the water pump. The opening command of the boiler recirculation valve is used for controlling the opening of the boiler recirculation valve, so that the flow of boiler recirculation water is changed, but the influence on the flow of boiler feed water is caused. The opening command of the water supply bypass is used for controlling the opening of a water supply door bypass adjusting valve, so that the water supply flow of the boiler is changed, and the water supply flow of the boiler is controlled before the water supply bypass switches the main path. The feed pump rotational speed command is used for controlling the feed pump rotational speed, thereby changing the boiler feed water flow, and controlling the boiler feed water flow after the main path is switched by the feed water bypass. And the boiler feed water flow is controlled in an auxiliary mode before the main path is switched by the feed water bypass.

The starting process of the boiler of the thermal power generating unit is a process of continuously adding coal and water, so that the water feeding flow and the recycling flow need to be concerned all the time in the conventional starting process, and as the cleaning sewage of the boiler is discharged, particularly after the boiler is ignited, the feed water is heated and evaporated to be lost, the feed water flow and the recycling flow are in unstable states, and the monitoring and the adjustment are needed by operators all the time. The over-high flow can cause the water-full accident of the boiler, and the over-low flow can cause the cavitation damage of the pump and the overtemperature and dry burning of the boiler. The scheme provided by the embodiment realizes automatic control of water supply before a dry state, and even if personnel do not carry out manual instruction correction in time in special conditions, only the cleaning and starting time is increased, and boiler protection action and equipment damage can not be caused. The intensity and pressure of monitoring and operation of operators are greatly reduced.

Example 3

Fig. 3 shows a core controller for automatic control of water supply, which is used in an ultra-supercritical once-through boiler equipped with a steam-driven water-feeding pump thermal power generating unit, and the core controller 14 comprises a recirculation pump outlet regulating gate controller 21, a water supply regulating gate controller 22 and a water-feeding pump rotating speed instruction switcher 23.

And the controller 21 of the outlet adjusting door of the recirculation pump is used for carrying out proportional integral operation according to the deviation of the set value of the recirculation flow and the actual value of the recirculation flow to obtain a real-time opening instruction of the outlet adjusting door of the recirculation pump.

The recirculation pump outlet regulating valve controller adopts the deviation of a recirculation flow set value and an actual value to carry out proportional integral operation to obtain a real-time opening instruction of the recirculation pump outlet regulating valve, and the proportional coefficient and the integral time are obtained by a thermal control engineer through debugging by using an engineering experience method according to the working conditions of a production field. The actual value of the recirculation flow is read by the controller from the plant DCS system. The recirculation flow set value is formed by adding a first manual correction value, a coal supply signal 4-order function value and a water storage tank liquid level deviation value, the first manual correction value is used for adapting to the requirement of manually adjusting the flow according to the actual condition when in cold and hot cleaning, the coal supply function overcomes the system disturbance caused by boiler ignition and water supply evaporation when the coal amount is increased, the water storage tank liquid level deviation value is used for rapidly adjusting the flow when the system working condition is unstable, and the liquid level is stabilized by matching with a 360-valve, so that the operation safety of the recirculation pump is ensured.

The water supply regulating gate controller 22 is composed of an instruction switcher and a proportional-integral arithmetic unit, the instruction switcher defaults to output instructions of 10%, controls the bypass water supply regulating gate to keep 10% of opening, and switches to the proportional-integral arithmetic unit after reaching a first switching condition, wherein the proportional-integral arithmetic unit performs proportional-integral arithmetic operation according to the deviation between the set value of the water supply flow and the actual value of the water supply flow and outputs the opening instructions of the bypass water supply regulating gate.

The water supply regulating gate controller consists of an instruction switcher and a proportional-integral arithmetic unit, the instruction switcher defaults to output an instruction of 10 percent, so that the bypass regulating gate keeps 10 percent of opening, and the instability of the system caused by the measurement fluctuation of a pore plate under the working condition of small flow at the initial starting stage is eliminated. When the switching condition is reached (the water supply flow is more than 850t/h, the time is delayed for 10 minutes), the switching is carried out to a proportional integral arithmetic unit (a bypass water supply regulating valve opening degree instruction is output after the deviation of the water supply flow set value and the actual value is subjected to proportional integral arithmetic). The water supply flow set value is formed by adding a flow switcher and a manual correction value, the flow switcher outputs 900t/h by default, and the flow required during the starting period is met; and after the switching condition is met (the main bypass switching button is manually clicked), the switching is carried out to 1200t/h, and then manual correction is superposed to ensure that the bypass adjusting door reaches more than 70% of opening degree before the automatic switching operation of the main water supply bypass is carried out. After the water supply pump is automatically put into operation, the controller instruction switcher outputs an instruction to switch to a 100% instruction calculated through an inertia link, so that the bypass door is slowly opened to 100%, and a main water supply door full-opening instruction is triggered by a bypass door full-opening signal to finish the automatic operation of water supply main bypass switching.

The water feeding pump rotating speed instruction switcher 23 is used for controlling the rotating speed of the water feeding pump, the rotating speed value of the water feeding pump output by the water feeding pump rotating speed instruction switcher is 2400rpm by default, whether the second switching condition is achieved or not is judged, when the second switching condition is achieved, the rotating speed of the water feeding pump is switched to 3000rpm, an automatic input signal is generated after the rotating speed of the water feeding pump reaches 3000rpm and is delayed for 5 minutes, and the automatic input signal triggers the water feeding pump rotating speed instruction switcher to be switched to the automatic input stage of the water feeding pump.

The feed water pump rotational speed command switcher outputs 2400rpm by default. The critical range 2650-2850 rpm of a water feeding pump turbine is avoided, and the cleaning flow is not lower than 850 t/h. When the switching condition is reached (the bypass opening is larger than 70% and is delayed for 1 minute), the switching is carried out to 3000rpm, when the set value is reached and the delay is 5 minutes, the water feeding pump is put into operation automatically, and the automatic input signal triggers the instruction switcher to output and switch to the automatic output value of the conventional water feeding pump.

Example 4

Taking the unit No. 2 of the State Hua Jiujiang power plant as an example, the boiler is an ultra-supercritical parameter variable-pressure direct-current boiler, and is reheated once, has a single hearth and is in a front-rear wall opposed combustion mode; the external steam-water separator is provided with a furnace water recirculation system with the through-flow capacity not less than 25 percent of BMCR flow; the water feeding pump turbine is of a single-cylinder, last-stage double-split flow, single-shaft, double-drive, impulse type, lower-exhaust condensing type and external tangent conversion type; the water main circuit has the through-flow capacity of 100 percent, the water bypass has the through-flow capacity of 30 percent and is provided with a bypass adjusting valve; the unit DCS control system is a Harmonious MASC6 system.

Because the Harmonious MASC6 system has configuration development, the control device can be integrated in a set DCS control system, and the man-machine conversation interface, the signal acquisition function and the instruction output function of the DCS system are called to complete the control function. The core controller functions are logically configured as described in the technical content of section 5, and the proportionality coefficients and the integration time are obtained by a thermal control engineer through engineering experience method debugging according to the working conditions of the production field.

In the starting process of the unit, after the water feeding pump is started and water injection of the boiler is completed, an operator can put the automatic control function of the core controller into operation through a human-computer interface button, the controller controls the rotating speed of the water feeding pump to be 2400rpm, the opening degree of the bypass adjusting door to be 10%, and the recirculation flow is controlled to be within a set value range. At the moment, the operator can control the size of the recirculation flow by manually modifying the set value of the recirculation flow, so that the cleaning effect according with the requirement is achieved. Because the boiler cleaning flow demand is more than 850t/h, when the recirculation flow is changed by an operator to enable the water supply flow to be more than 850t/h, the water supply flow of the bypass adjusting valve is controlled to be put into closed-loop control, and the water supply flow is controlled to be maintained at 900 t/h. In the ignition and heating and boosting processes of the boiler, the set value of the recirculation flow changes along with the change of the coal quantity and the change of the liquid level of the water storage tank, the influence of the evaporation capacity of the feed water and the influence of the liquid level fluctuation of the water storage tank are balanced, and the operation safety of the system is ensured. And (3) with the continuous heating and boosting of the boiler, after the dry-wet state conversion of the boiler is completed and the recirculation system is stopped, operating personnel control the main water supply bypass to automatically implement switching through a human-computer interface button, the set value of the water supply flow is automatically modified to 1200t/h in the process, and the operating personnel ensure that the opening of the bypass is larger than 70% by changing the corrected value of the water supply flow. After the opening degree of the bypass valve is larger than 70% and the delay time is 1 minute, the rotating speed command of the water feeding pump is switched to 3000 rpm. After the rotation speed reaches 3000rpm and the delay time is 5 minutes, the feed water flow of the feed water pump is controlled in a closed loop mode. After the water supply pump is automatically put into operation, the controller controls the bypass door to be slowly opened to 100%, and the controller controls the main water supply door to be fully opened after the bypass door is fully opened. And when the recirculation system is withdrawn, the water supply valve is fully opened, the water supply pump is controlled by the water supply main control, the function of the controller is completed, and the operation is withdrawn.

In addition, the embodiment of the present disclosure further provides a feedwater automatic control device, including: a memory, a processor and a computer program stored on the memory and executable on the processor, the computer program, when executed by the processor, implementing the steps of the water supply automatic control method as provided in the preceding embodiments.

The embodiments of the present disclosure also provide a computer-readable storage medium, on which a computer program is stored, and the computer program, when executed by a processor, implements the steps of the automatic water supply control method provided in the foregoing embodiments.

By adopting the scheme provided by the embodiment of the invention, in the starting process of the unit, the operator can control the switching time by manually correcting the recirculation flow set value and the water supply flow set value and operating the water supply switching button according to the actual working condition, and the ideal water supply control effect of the whole starting process of the unit can be achieved. The high-intensity working mode that multi-parameter monitoring and multi-equipment operation are manually carried out in the conventional starting process is changed, and the risks of manual monitoring failure and equipment misoperation are avoided.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The above description is only an example of the present invention, and is not intended to limit the present invention. Various modifications and alterations to this invention will become apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.