High-pressure heater emergency drain regulating valve control method and configuration system

Abstract

The invention relates to the technical field of automatic control, and discloses a high-pressure heater emergency drain regulating valve control method and a configuration system. The method comprises the following steps: when three conditions that the water level of a high-pressure heater is lower than a high-pressure heater water level binary value, a high-pressure heater emergency drain control valve instruction is not greater than a preset valve opening degree and a high-pressure heater emergency drain control valve PID water level set value is not smaller than the water level of the high-pressure heater are simultaneously met and the holding time exceeds a preset time, judging whether the high-pressure heater is in an emergency drain state; the override closing function of the high-pressure heater emergency drain regulating valve is triggered, so that the high-pressure heater emergency drain regulating valve is always in a fully-closed state, the problem that when the water level of the high-pressure heater rises within a normal range, the emergency drain regulating valve is automatically opened due to the proportional action of the PID controller, and large disturbance is caused to water level control can be solved, and the running safety of a unit is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automatic control, and particularly relates to a control method and configuration system for a high-pressure heater emergency drain regulating valve. Background Art

[0002] The water level control of high-pressure heaters in thermal power plants has an important impact on the safe and economic operation of the unit. During the normal operation of the unit, the water level of the high-pressure heater is automatically controlled by both the normal drain regulating valve PID controller and the emergency drain regulating valve PID controller of the high-pressure heater. When the water level is within the normal range, the water level is regulated by the normal drain regulating valve PID controller, and the emergency drain regulating valve is in the fully closed state; when the water level is on the high side, the emergency drain regulating valve needs to be opened to participate in the water level regulation. If the emergency drain regulating valve of the high-pressure heater is accidentally opened when the water level is normal, it will cause a large disturbance to the water level control of the high-pressure heater and affect the safe operation of the unit. Therefore, how to prevent the emergency drain regulating valve of the high-pressure heater from being accidentally opened when the water level is within the normal range has become the key research content. Summary of the Invention

[0003] In view of this, the present invention provides a control method and configuration system for a high-pressure heater emergency drain regulating valve to solve the problem that the emergency drain regulating valve of the high-pressure heater is accidentally opened when the water level is within the normal range.

[0004] In a first aspect, the present invention provides a control method for a high-pressure heater emergency drain regulating valve, and the method includes:

[0005] Obtain the PID water level set value of the high-pressure heater emergency drain regulating valve, the water level of the high-pressure heater, and the high-high value of the high-pressure heater water level;

[0006] Compare the water level of the high-pressure heater with the high-high value of the high-pressure heater water level, compare the emergency drain regulating valve command of the high-pressure heater with the preset valve opening, and compare the PID water level set value of the high-pressure heater emergency drain regulating valve with the water level of the high-pressure heater;

[0007] When the three conditions that the water level of the high-pressure heater is less than the high-high value of the high-pressure heater water level, the emergency drain regulating valve command of the high-pressure heater is not greater than the preset valve opening, and the PID water level set value of the high-pressure heater emergency drain regulating valve is not less than the water level of the high-pressure heater are simultaneously satisfied and the holding time exceeds the preset time, trigger the override closing function of the high-pressure heater emergency drain regulating valve.

[0008] A control method for the emergency drain regulating valve of a high-pressure heater provided by the present invention can trigger the override closing function of the emergency drain regulating valve of the high-pressure heater when the water level of the high-pressure heater is less than the second high value, the command of the emergency drain regulating valve of the high-pressure heater is less than or equal to 1%, and the PID water level set value of the emergency drain regulating valve of the high-pressure heater is greater than or equal to the water level of the high-pressure heater for more than 120 s at the same time, so that it is always in a fully closed state, which can prevent the problem that when the water level of the high-pressure heater rises within the normal range, the emergency drain regulating valve automatically opens due to the proportional action of the PID controller, causing a large disturbance to the water level control, and improves the safety of the unit operation.

[0009] In an alternative embodiment, the method further includes:

[0010] When the water level of the high-pressure heater is not less than the second high value of the water level of the high-pressure heater, trigger the override open function of the emergency drain regulating valve of the high-pressure heater.

[0011] In an alternative embodiment, the method further includes:

[0012] Perform PID control on the opening of the emergency drain regulating valve of the high-pressure heater according to the PID water level set value of the emergency drain regulating valve of the high-pressure heater and the water level of the high-pressure heater.

[0013] In an alternative embodiment, the method further includes:

[0014] When the PID water level set value of the emergency drain regulating valve of the high-pressure heater is greater than the water level of the high-pressure heater, control the opening of the emergency drain regulating valve of the high-pressure heater to decrease;

[0015] When the PID water level set value of the emergency drain regulating valve of the high-pressure heater is less than the water level of the high-pressure heater, control the opening of the emergency drain regulating valve of the high-pressure heater to increase;

[0016] When the PID water level set value of the emergency drain regulating valve of the high-pressure heater is equal to the water level of the high-pressure heater, control the opening of the emergency drain regulating valve of the high-pressure heater to remain unchanged.

[0017] In an alternative embodiment, the method further includes:

[0018] After triggering the override closing function of the emergency drain regulating valve of the high-pressure heater, control the emergency drain regulating valve to override close, and the opening of the emergency drain regulating valve of the high-pressure heater decreases;

[0019] After triggering the override open function of the emergency drain regulating valve of the high-pressure heater, control the emergency drain regulating valve to override open, and the opening of the emergency drain regulating valve of the high-pressure heater increases.

[0020] In an alternative embodiment, the method further includes:

[0021] The priority of the opening control function of the high-pressure heater emergency drain regulating valve is, from high to low, the override closing function of the high-pressure heater emergency drain regulating valve, the override opening function of the high-pressure heater emergency drain regulating valve, and the PID control.

[0022] In an alternative embodiment, the method further includes:

[0023] Obtain the PID water level set value of the normal drain regulating valve of the high-pressure heater;

[0024] Perform a summation calculation on the PID water level set value of the normal drain regulating valve of the high-pressure heater and a preset water level value to obtain the PID water level set value of the high-pressure heater emergency drain regulating valve.

[0025] In a second aspect, the present invention provides a configuration system for a high-pressure heater emergency drain regulating valve. The configuration system includes: a PID function block, a first comparison function block, a second comparison function block, a third comparison function block, a logical NOT function block, a logical AND function block, and a delay function block. Among them,

[0026] The first input end of the first comparison function block inputs the high-pressure heater water level, the second input end of the first comparison function block inputs the high-pressure heater water level high value 2. The first comparison function block inputs the comparison result of the high-pressure heater water level and the high-pressure heater water level high value 2 to the logical NOT function block for a NOT operation, and the logical NOT function block inputs the NOT operation result to the first input end of the logical AND function block;

[0027] The first input end of the second comparison function block inputs the high-pressure heater emergency drain regulating valve command, the second input end of the second comparison function block inputs a preset valve opening. The second comparison function block inputs the comparison result of the high-pressure heater emergency drain regulating valve command and the preset valve opening to the second input end of the logical AND function block;

[0028] The first input end of the third comparison function block inputs the PID water level set value of the high-pressure heater emergency drain regulating valve, the second input end of the third comparison function block inputs the high-pressure heater water level. The third comparison function block inputs the comparison result of the PID water level set value of the high-pressure heater emergency drain regulating valve and the high-pressure heater water level to the third input end of the logical AND function block;

[0029] The first input end of the delay function block is connected to the output end of the logical AND function block, the second input end of the delay function block inputs a preset time, and the output end of the delay function block is connected to the override close control end of the PID function block;

[0030] When the water level of the high-pressure heater is less than the second high value of the water level of the high-pressure heater, the command of the emergency drain control valve of the high-pressure heater is not greater than the preset valve opening, and the PID water level set value of the emergency drain control valve of the high-pressure heater is not less than the water level of the high-pressure heater, and when these three conditions are simultaneously satisfied and maintained for more than the preset time, the overrun closing function of the emergency drain control valve of the high-pressure heater is triggered.

[0031] A configuration system for the emergency drain control valve of a high-pressure heater provided by the present invention triggers the overrun closing function of the emergency drain control valve of the high-pressure heater when the water level of the high-pressure heater is less than the second high value, the command of the emergency drain control valve of the high-pressure heater is less than or equal to 1%, and the PID water level set value of the emergency drain control valve of the high-pressure heater is greater than or equal to the water level of the high-pressure heater, and these three conditions are simultaneously satisfied for more than 120 s, so that it is always in a fully closed state, which can prevent the emergency drain control valve from automatically opening due to the proportional action of the PID controller when the water level of the high-pressure heater rises within the normal range, causing a large disturbance to the water level control, and improves the safety of the unit operation.

[0032] In an optional implementation manner, the configuration system further includes:

[0033] The first comparison function block inputs the comparison result of the water level of the high-pressure heater and the second high value of the water level of the high-pressure heater to the overrun open control end of the PID function block;

[0034] When the water level of the high-pressure heater is not less than the second high value of the water level of the high-pressure heater, the overrun open function of the emergency drain control valve of the high-pressure heater is triggered.

[0035] In an optional implementation manner, the configuration system further includes:

[0036] The set value input end of the PID function block inputs the PID water level set value of the emergency drain control valve of the high-pressure heater, and the process measurement value input end of the PID function block inputs the water level of the high-pressure heater. Description of the Drawings

[0037] In order to more clearly illustrate the specific implementation manners of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific implementation manners or the prior art. Obviously, the following drawings are some implementation manners of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0038] Figure 1 It is a schematic diagram of the automatic control logic configuration of the emergency drain control valve in the related art according to an embodiment of the present invention;

[0039] Figure 2It is a schematic flow chart of a control method for a high-pressure heater emergency drain regulating valve according to an embodiment of the present invention;

[0040] Figure 3 It is a schematic diagram of the configuration of a high-pressure heater emergency drain regulating valve according to an embodiment of the present invention. Detailed implementation manners

[0041] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0043] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can also be the communication inside two elements. It can be a wireless connection or a wired connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0044] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0045] Related technologies such as Figure 1As shown, in the automatic control logic of the emergency drain regulating valve, the PID set value of the emergency drain regulating valve is 50 mm higher than that of the normal drain regulating valve, and the emergency drain regulating valve overrides and opens when the water level reaches the high level II value. When the water level of the high-pressure heater rises within the normal range, the emergency drain regulating valve will automatically open due to the proportional action of the PID controller, causing a large disturbance to the water level control and affecting the safe operation of the unit. Therefore, there is an urgent need for a logic configuration method that can solve the problem of the emergency drain regulating valve accidentally opening in the fully closed state when the water level of the high-pressure heater is within the normal range, which is of great significance for improving the safe operation of the unit.

[0046] For this reason, the present invention provides a control method for the emergency drain regulating valve of a high-pressure heater to solve the problem that when the water level of the high-pressure heater in the prior art rises within the normal range, the emergency drain regulating valve automatically opens in the fully closed state, causing a large disturbance to the water level control and affecting the safe operation of the unit.

[0047] According to an embodiment of the present invention, there is provided an embodiment of a control method for an emergency drain regulating valve of a high-pressure heater. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0048] In this embodiment, a control method for an emergency drain regulating valve of a high-pressure heater is provided, which can be applied to the water level control of a high-pressure heater in a thermal power plant. Figure 2 It is a flowchart of the control method for the emergency drain regulating valve of the high-pressure heater according to an embodiment of the present invention, as Figure 2 shown, this process includes the following steps:

[0049] Step S1, obtain the PID water level set value of the emergency drain regulating valve of the high-pressure heater, the water level of the high-pressure heater, and the high level II value of the water level of the high-pressure heater.

[0050] Specifically, the water level of the high-pressure heater is detected by a water level sensor. The high level II value of the water level of the high-pressure heater is determined by technicians according to the safe operation conditions of the unit. As Figure 3As shown in the figure, the PID water level set value of the high-pressure heater emergency drain regulating valve is obtained in the following way: First, obtain the PID water level set value of the high-pressure heater normal drain regulating valve, input the PID water level set value of the high-pressure heater normal drain regulating valve into the first input terminal X1 of the addition function block ADD, input the preset water level value into the second input terminal X2 of the addition function block ADD, and then perform a summation calculation on the PID water level set value of the high-pressure heater normal drain regulating valve and the preset water level value in the addition function block ADD. The output terminal Y of the addition function block ADD outputs the summation calculation result, that is, the PID water level set value of the high-pressure heater emergency drain regulating valve. Then, the PID water level set value of the high-pressure heater emergency drain regulating valve output by the output terminal Y is input into the set value input terminal SP of the PID function block. Among them, the PID water level set value of the high-pressure heater normal drain regulating valve is also determined by technicians according to the safe operation conditions of the unit. In the embodiment of the present invention, the preset water level value is generally set to 50 mm.

[0051] Step S2: Compare the high-pressure heater water level with the high-pressure heater high water level value, compare the high-pressure heater emergency drain regulating valve command with the preset valve opening, and compare the PID water level set value of the high-pressure heater emergency drain regulating valve with the high-pressure heater water level.

[0052] Specifically, as Figure 3 shown in the figure, input the high-pressure heater water level into the first input terminal X1 of the first comparison function block GE1, input the high-pressure heater high water level value into the second input terminal X2 of the first comparison function block GE1, and in the first comparison function block GE1, compare the high-pressure heater water level with the high-pressure heater high water level value. Input the high-pressure heater emergency drain regulating valve command into the first input terminal X1 of the second comparison function block LE, input the preset valve opening into the second input terminal X2 of the second comparison function block LE, and in the second comparison function block LE, compare the high-pressure heater emergency drain regulating valve command with the preset valve opening. Input the output terminal Y value of the addition function block ADD, that is, the PID water level set value of the high-pressure heater emergency drain regulating valve, into the first input terminal X1 of the third comparison function block GE2, input the high-pressure heater water level into the second input terminal X2 of the third comparison function block GE2, and in the third comparison function block GE2, compare the PID water level set value of the high-pressure heater emergency drain regulating valve with the high-pressure heater water level.

[0053] Step S3: When the three conditions that the high-pressure heater water level is less than the high-pressure heater high water level value, the high-pressure heater emergency drain regulating valve command is not greater than the preset valve opening, and the PID water level set value of the high-pressure heater emergency drain regulating valve is not less than the high-pressure heater water level are simultaneously satisfied and the holding time exceeds the preset time, trigger the overrun closing function of the high-pressure heater emergency drain regulating valve.

[0054] Specifically, in the first comparison function block GE1, when the water level of the high-pressure heater ≥ the second high water level value of the high-pressure heater, the output terminal Y of the first comparison function block GE1 = 1; when the water level of the high-pressure heater < the second high water level value of the high-pressure heater, the output terminal Y of the first comparison function block GE1 = 0, and the Y value is input to the input terminal X of the logic NOT function block NOT. After the logic NOT function block NOT performs the NOT operation, the result of the NOT operation is input to the first input terminal X1 of the logic AND function block AND.

[0055] In the second comparison function block LE, when the emergency drain valve command of the high-pressure heater ≤ the preset valve opening, the output terminal Y of the second comparison function block = 1; when the emergency drain valve command of the high-pressure heater > the preset valve opening, the output terminal Y of the second comparison function block = 0, and the Y value is input to the second input terminal X2 of the logic AND function block AND. Among them, the preset valve opening is 1%.

[0056] In the third comparison function block GE2, when the PID water level set value of the high-pressure heater emergency drain regulating valve ≥ the water level of the high-pressure heater, the output terminal Y of the third comparison function block GE2 = 1; when the PID water level set value of the high-pressure heater emergency drain regulating valve < the water level of the high-pressure heater, the output terminal Y of the third comparison function block GE2 = 0, and the Y value is input to the third input terminal X3 of the logic AND function block AND.

[0057] When the first input terminal X1, the second input terminal X2, and the third input terminal X3 of the logic AND function block AND are all 1, the output terminal D = 1; otherwise the output terminal D = 0. The D value of the output terminal of the logic AND function block AND is input to the first input terminal X of the delay function block TON, the second input terminal T of the delay function block TON inputs the preset time, when X = 1 and the holding time exceeds the T value, the output terminal Y of the delay function block TON = 1; otherwise Y = 0. The output terminal Y of the delay function block TON is input to the override close control terminal DECOV of the PID function block. When DECOV = 1, at this time, the override close function of the high-pressure heater emergency drain regulating valve is triggered, the emergency drain regulating valve is controlled to close overriddenly, and the opening of the high-pressure heater emergency drain regulating valve decreases. Among them, the preset time is 120s.

[0058] A control method for a high-pressure heater emergency drain regulating valve provided by the present invention triggers the override close function of the high-pressure heater emergency drain regulating valve when the three conditions that the water level of the high-pressure heater is less than the second high value, the command of the high-pressure heater emergency drain regulating valve is less than or equal to 1%, and the PID water level set value of the high-pressure heater emergency drain regulating valve is greater than or equal to the water level of the high-pressure heater are simultaneously satisfied for more than 120s, so that it is always in a fully closed state, which can prevent the emergency drain regulating valve from automatically opening due to the proportional action of the PID controller when the water level of the high-pressure heater rises within the normal range, causing a large disturbance to the water level control, and improves the safety of the unit operation.

[0059] In an alternative embodiment, the method further includes:

[0060] Step S4, when the water level of the high-pressure heater is not less than the second high value of the high-pressure heater water level, trigger the override open function of the emergency drain regulating valve of the high-pressure heater.

[0061] Specifically, the Y value at the output end of the first comparison function block GE1 is also input to the override open control end INCOV of the PID function block. When the water level of the high-pressure heater ≥ the second high value of the high-pressure heater water level, the Y value at the output end of the first comparison function block GE1 = 1, INCOV = 1, triggering the override open function of the emergency drain regulating valve of the high-pressure heater. At this time, the command of the emergency drain regulating valve of the high-pressure heater increases, and the emergency drain regulating valve opens in override. When the water level of the high-pressure heater < the second high value of the high-pressure heater water level, the Y value at the output end of the first comparison function block GE1 = 0, INCOV = 0, and the override open function fails.

[0062] In an alternative embodiment, the method further includes:

[0063] Step S5, perform PID control on the opening of the emergency drain regulating valve of the high-pressure heater according to the PID water level setting value of the emergency drain regulating valve of the high-pressure heater and the water level of the high-pressure heater.

[0064] Specifically, the PID function block is a proportional-integral-derivative control function block. The set value input terminal SP of the PID function block inputs the PID water level setting value of the emergency drain regulating valve of the high-pressure heater, and the process measurement value input terminal PV of the PID function block inputs the water level of the high-pressure heater. In the PID function block, the value at the set value input terminal SP and the value at the process measurement value input terminal PV are compared, and the command of the emergency drain regulating valve is controlled through proportional, integral, and derivative actions. When the water level of the high-pressure heater > the PID water level setting value of the emergency drain regulating valve of the high-pressure heater, the opening of the emergency drain regulating valve of the high-pressure heater increases; when the water level of the high-pressure heater < the PID water level setting value of the emergency drain regulating valve of the high-pressure heater, the opening of the emergency drain regulating valve of the high-pressure heater decreases; when the PID water level setting value of the emergency drain regulating valve of the high-pressure heater = the water level of the high-pressure heater, the opening of the emergency drain regulating valve remains unchanged.

[0065] In an alternative embodiment, the method further includes:

[0066] Step S6, after triggering the override close function of the emergency drain regulating valve of the high-pressure heater, control the emergency drain regulating valve to close in override, and the opening of the emergency drain regulating valve of the high-pressure heater decreases.

[0067] Step S7, after triggering the override open function of the emergency drain regulating valve of the high-pressure heater, control the emergency drain regulating valve to open in override, and the opening of the emergency drain regulating valve of the high-pressure heater increases.

[0068] Specifically, when DECOV = 1, the override closing function of the high-pressure heater emergency drain regulating valve is triggered, controlling the override closing of the emergency drain regulating valve, and the opening of the high-pressure heater emergency drain regulating valve decreases. When DECOV = 0, the override closing function fails.

[0069] When INCOV = 1, the override opening function of the high-pressure heater emergency drain regulating valve is triggered, controlling the override opening of the emergency drain regulating valve, and the opening of the high-pressure heater emergency drain regulating valve increases. When INCOV = 0, the override opening function fails.

[0070] Furthermore, the priority of the opening control function of the high-pressure heater emergency drain regulating valve is, from high to low, the override closing function of the high-pressure heater emergency drain regulating valve, the override opening function of the high-pressure heater emergency drain regulating valve, and PID control.

[0071] The present invention provides a configuration system for a high-pressure heater emergency drain regulating valve, as Figure 3 shown, including: a PID function block, a first comparison function block GE1, a second comparison function block LE, a third comparison function block GE2, a logical NOT function block NOT, a logical AND function block AND, and a time delay function block TON.

[0072] Among them, the first input terminal X1 of the first comparison function block GE1 inputs the high-pressure heater water level, the second input terminal X2 of the first comparison function block GE1 inputs the high water level value of the high-pressure heater, and the comparison result of the high-pressure heater water level and the high water level value of the high-pressure heater by the first comparison function block GE1 is input to the logical NOT function block NOT for negation operation. The logical NOT function block NOT inputs the negation operation result to the first input terminal X1 of the logical AND function block AND. The first input terminal X1 of the second comparison function block LE inputs the high-pressure heater emergency drain regulating valve command, the second input terminal X2 of the second comparison function block LE inputs the preset valve opening, and the comparison result of the high-pressure heater emergency drain regulating valve command and the preset valve opening by the second comparison function block LE is input to the second input terminal X2 of the logical AND function block AND. The first input terminal X1 of the third comparison function block GE2 inputs the PID water level setting value of the high-pressure heater emergency drain regulating valve, the second input terminal X2 of the third comparison function block GE2 inputs the high-pressure heater water level, and the comparison result of the PID water level setting value of the high-pressure heater emergency drain regulating valve and the high-pressure heater water level by the third comparison function block GE2 is input to the third input terminal X3 of the logical AND function block AND. The first input terminal X of the time delay function block TON is connected to the output terminal of the logical AND function block AND, the second input terminal T of the time delay function block TON inputs the preset time, and the output terminal Y of the time delay function block TON is connected to the override close control terminal DECOV of the PID function block.

[0073] When the water level of the high-pressure heater is less than the second high value of the high-pressure heater water level, the command of the high-pressure heater emergency drain valve is not greater than the preset valve opening, and the PID water level setting value of the high-pressure heater emergency drain valve is not less than the high-pressure heater water level, and these three conditions are simultaneously satisfied and maintained for more than the preset time, the overrun closing function of the high-pressure heater emergency drain valve is triggered.

[0074] Specifically, as Figure 3 shown, GE1 is a comparison function block. When X1≥X2, Y = 1; when X1<X2, Y = 0. LE is a comparison function block. When X1≤X2, Y = 1; when X1>X2, Y = 0. TON is a delay function block. When X = 1 and the duration exceeds T, Y = 1; when X = 0 or (X = 1 and the duration is less than T), Y = 0; T is the time constant.

[0075] Furthermore, in the first comparison function block GE1, when the high-pressure heater water level ≥ the second high value of the high-pressure heater water level, the output terminal Y of the first comparison function block GE1 = 1; when the high-pressure heater water level < the second high value of the high-pressure heater water level, the output terminal Y of the first comparison function block GE1 = 0, and the Y value is input to the input terminal X of the logic NOT function block NOT. After the logic NOT function block NOT performs the negation operation, the result of the negation operation is input to the first input terminal X1 of the logic AND function block AND.

[0076] In the second comparison function block LE, when the command of the high-pressure heater emergency drain valve ≤ the preset valve opening, the output terminal Y of the second comparison function block = 1; when the command of the high-pressure heater emergency drain valve > the preset valve opening, the output terminal Y of the second comparison function block = 0, and the Y value is input to the second input terminal X2 of the logic AND function block AND. Among them, the preset valve opening is 1%.

[0077] In the third comparison function block GE2, when the PID water level setting value of the high-pressure heater emergency drain valve ≥ the high-pressure heater water level, the output terminal Y of the third comparison function block GE2 = 1; when the PID water level setting value of the high-pressure heater emergency drain valve < the high-pressure heater water level, the output terminal Y of the third comparison function block GE2 = 0, and the Y value is input to the third input terminal X3 of the logic AND function block AND.

[0078] When the first input terminal X1, the second input terminal X2, and the third input terminal X3 of the logic and function block AND are all 1, the output terminal D = 1; otherwise, the output terminal D = 0. The value of the output terminal D of the logic and function block AND is input to the first input terminal X of the delay function block TON. The second input terminal T of the delay function block TON inputs a preset time. When X = 1 and the holding time exceeds the value of T, the output terminal Y of the delay function block TON = 1; otherwise, Y = 0. The output terminal Y of the delay function block TON is input to the override close control terminal DECOV of the PID function block. When DECOV = 1, the override close function of the high-pressure heater emergency drain regulating valve is triggered at this time, controlling the override close of the emergency drain regulating valve, and the opening of the high-pressure heater emergency drain regulating valve decreases.

[0079] A high-pressure heater emergency drain regulating valve configuration system provided by the present invention triggers the override close function of the high-pressure heater emergency drain regulating valve when three conditions, namely, the water level of the high-pressure heater is less than the second high value, the command of the high-pressure heater emergency drain regulating valve is less than or equal to 1%, and the PID water level setting value of the high-pressure heater emergency drain regulating valve is greater than or equal to the water level of the high-pressure heater, are simultaneously satisfied for more than 120 s, so that it is always in a fully closed state, which can prevent the problem that when the water level of the high-pressure heater rises within the normal range, the emergency drain regulating valve automatically opens due to the proportional action of the PID controller, causing a large disturbance to the water level control, and improves the safety of the unit operation.

[0080] In an optional implementation manner, as Figure 3 shown, the configuration system further includes: The comparison result of the first comparison function block GE1 between the water level of the high-pressure heater and the second high value of the water level of the high-pressure heater is input to the override open control terminal INCOV of the PID function block. When the water level of the high-pressure heater is not less than the second high value of the water level of the high-pressure heater, the override open function of the high-pressure heater emergency drain regulating valve is triggered.

[0081] Specifically, the output terminal Y value of the first comparison function block GE1 is also input to the override open control terminal INCOV of the PID function block. When the water level of the high-pressure heater ≥ the second high value of the water level of the high-pressure heater, the output terminal Y of the first comparison function block GE1 = 1, INCOV = 1, triggering the override open function of the high-pressure heater emergency drain regulating valve. At this time, the command of the high-pressure heater emergency drain regulating valve increases, and the emergency drain regulating valve is overridden to open. When the water level of the high-pressure heater < the second high value of the water level of the high-pressure heater, the output terminal Y of the first comparison function block GE1 = 0, INCOV = 0, and the override open function fails.

[0082] In an optional implementation manner, as Figure 3 shown, the configuration system further includes:

[0083] The setpoint input terminal SP of the PID function block inputs the PID water level setpoint of the emergency drain regulating valve for the high-pressure heater, and the process measurement value input terminal PV of the PID function block inputs the water level of the high-pressure heater.

[0084] Specifically, the PID function block is a proportional-integral-derivative control function block. The setpoint input terminal SP of the PID function block inputs the PID water level setpoint of the emergency drain regulating valve for the high-pressure heater, and the process measurement value input terminal PV of the PID function block inputs the water level of the high-pressure heater. In the PID function block, the value of the setpoint input terminal SP and the value of the process measurement value input terminal PV are compared, and the command of the emergency drain regulating valve is controlled through proportional, integral, and derivative actions. When the water level of the high-pressure heater > the PID water level setpoint of the emergency drain regulating valve for the high-pressure heater, the opening of the emergency drain regulating valve for the high-pressure heater increases; when the water level of the high-pressure heater < the PID water level setpoint of the emergency drain regulating valve for the high-pressure heater, the opening of the emergency drain regulating valve for the high-pressure heater decreases; when the PID water level setpoint of the emergency drain regulating valve for the high-pressure heater = the water level of the high-pressure heater, the opening of the emergency drain regulating valve remains unchanged.

[0085] In an alternative embodiment, as Figure 3 shown, the configuration system further includes: an addition function block ADD. The first input terminal X1 of the addition function block ADD inputs the PID water level setpoint of the normal drain regulating valve for the high-pressure heater, the second input terminal X2 of the addition function block ADD inputs a preset water level value, and then the PID water level setpoint of the normal drain regulating valve for the high-pressure heater and the preset water level value are summed in the addition function block ADD. The output terminal Y of the addition function block ADD outputs the summation result, that is, the PID water level setpoint of the emergency drain regulating valve for the high-pressure heater.

[0086] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A method for controlling a high-pressure heater emergency drain regulating valve, characterized in that: The method comprises: Obtain the PID water level setting value of the high-pressure heater emergency drain regulating valve, the high-pressure heater water level and the high-pressure heater water level high value; Compare the high-pressure heater water level with the high-pressure heater water level high value, compare the high-pressure heater emergency drain control valve instruction with the preset valve opening, and compare the high-pressure heater emergency drain control valve PID water level setting value with the high-pressure heater water level; When the three conditions that the high-pressure heater water level is less than the high-pressure heater water level high second value, the high-pressure heater emergency drain regulating valve instruction is not greater than the preset valve opening, and the high-pressure heater emergency drain regulating valve PID water level setting value is not less than the high-pressure heater water level are met at the same time and the maintenance time exceeds the preset time, the high-pressure heater emergency drain regulating valve override closing function is triggered.

2. The high-pressure heater emergency drain regulating valve control method according to claim 1, characterized in that: The method further comprises: When the water level of the high-pressure heater is not less than the high-pressure heater water level high second value, the overrun opening function of the high-pressure heater emergency drain regulating valve is triggered.

3. The high-pressure heater emergency drain regulating valve control method according to claim 2, characterized in that: The method further comprises: The opening of the high-pressure heater emergency drain regulating valve is PID controlled according to the PID water level setting value of the high-pressure heater emergency drain regulating valve and the high-pressure heater water level.

4. The high-pressure heater emergency drain regulating valve control method according to claim 3, characterized in that: The method further comprises: When the PID water level setting value of the high-pressure heater emergency drain regulating valve is greater than the high-pressure heater water level, the opening of the high-pressure heater emergency drain regulating valve is controlled to decrease; When the PID water level setting value of the high-pressure heater emergency drain regulating valve is less than the high-pressure heater water level, the opening of the high-pressure heater emergency drain regulating valve is controlled to increase; When the PID water level setting value of the high-pressure heater emergency drain regulating valve is equal to the high-pressure heater water level, the opening of the high-pressure heater emergency drain regulating valve is controlled to remain unchanged.

5. The high-pressure heater emergency drain regulating valve control method according to claim 3, characterized in that: The method further comprises: When the high-pressure heater emergency drain regulating valve override closing function is triggered, the emergency drain regulating valve is controlled to override and close, and the opening of the high-pressure heater emergency drain regulating valve is reduced; When the high-pressure heater emergency drain regulating valve overrun opening function is triggered, the emergency drain regulating valve is controlled to overrun and open, and the opening of the high-pressure heater emergency drain regulating valve increases.

6. The high-pressure heater emergency drain regulating valve control method according to claim 5, characterized in that: The method further comprises: The priority of the high-pressure heater emergency drain regulating valve opening control function is from high to low as follows: high-pressure heater emergency drain regulating valve override closing function, high-pressure heater emergency drain regulating valve override opening function, and PID control.

7. The high-pressure heater emergency drain regulating valve control method according to claim 1, characterized in that: The method further comprises: Get the PID water level setting value of the normal drain regulating valve of the high-pressure heater; The PID water level setting value of the normal drain regulating valve of the high-pressure heater is summed with the preset water level value to obtain the PID water level setting value of the emergency drain regulating valve of the high-pressure heater.

8. A high-pressure heater emergency drain regulating valve configuration system, characterized in that: The configuration system includes: a PID function block, a first comparison function block, a second comparison function block, a third comparison function block, a logic non-function block, a logic and function block and a delay function block, wherein: The first input terminal of the first comparison function block inputs the high-pressure heater water level, the second input terminal of the first comparison function block inputs the high-pressure heater water level high value two, the first comparison function block inputs the comparison result of the high-pressure heater water level and the high-pressure heater water level high value two to the logic negation function block for negation operation, and the logic negation function block inputs the negation operation result to the first input terminal of the logic and function block; The first input terminal of the second comparison function block inputs the high-pressure heater emergency drain control command, the second input terminal of the second comparison function block inputs the preset valve opening, and the second comparison function block inputs the comparison result between the high-pressure heater emergency drain control command and the preset valve opening into the second input terminal of the logic and function block; The first input terminal of the third comparison function block inputs the PID water level setting value of the high-pressure heater emergency drain regulating valve, the second input terminal of the third comparison function block inputs the high-pressure heater water level, and the third comparison function block inputs the comparison result of the PID water level setting value of the high-pressure heater emergency drain regulating valve and the high-pressure heater water level to the third input terminal of the logic and function block; The first input end of the delay function block is connected to the output end of the logic and function block, the second input end of the delay function block inputs a preset time, and the output end of the delay function block is connected to the override control end of the PID function block; When the three conditions that the high-pressure heater water level is less than the high-pressure heater water level high second value, the high-pressure heater emergency drain regulating valve instruction is not greater than the preset valve opening, and the high-pressure heater emergency drain regulating valve PID water level setting value is not less than the high-pressure heater water level are met at the same time and the maintenance time exceeds the preset time, the high-pressure heater emergency drain regulating valve override closing function is triggered.

9. The high-pressure heater emergency drain regulating valve configuration system according to claim 8, characterized in that: The configuration system also includes: The first comparison function block inputs the comparison result of the high-pressure heater water level and the high-pressure heater water level high second value into the override open control terminal of the PID function block; When the water level of the high-pressure heater is not less than the high-pressure heater water level high second value, the overrun opening function of the high-pressure heater emergency drain regulating valve is triggered.

10. The high-pressure heater emergency drain regulating valve configuration system according to claim 8, characterized in that: The configuration system also includes: The set value input end of the PID function block inputs the PID water level set value of the high-pressure heater emergency drain regulating valve, and the process measurement value input end of the PID function block inputs the high-pressure heater water level.

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