A two-stage regulating valve dynamic coordinated control straight-mix condenser system

Abstract

The application discloses a two-stage regulating valve dynamic cooperative control direct mixing condenser system, which comprises a condenser shell, a water chamber arranged in the condenser shell and a steam cooling space formed between the condenser shell and the water chamber; a plurality of groups of nozzles are arranged on the water chamber and face the steam cooling space, and the water chamber is divided into a plurality of sub-zones corresponding to the number of the groups of nozzles, so that each sub-zone corresponds to a group of nozzles; a water pump, a first-stage coarse regulating valve and second-stage fine regulating valves are sequentially arranged on a water inlet pipeline connected with the water chamber along the water inlet direction, the second-stage fine regulating valves are arranged side by side, and each second-stage fine regulating valve is communicated with a corresponding sub-zone through a branch; the first-stage coarse regulating valve is configured to perform pressure division regulation, and the second-stage fine regulating valves are configured to perform flow regulation; the second-stage fine regulating valves are regulated by using the same opening degree instruction; the two-stage regulating valve combination is utilized, and the control principle of decoupling operation is combined, so that the interference in the regulating process of the two-stage regulating valves is avoided, and the reliability and cooling speed are improved.

Description

Technical Field

[0001] This invention belongs to the field of steam power system condenser technology, specifically relating to a direct mixing condensation system with dynamic coordinated control of two-stage regulating valves. Background Technology

[0002] As the power levels of steam power systems gradually increase, the size of their steam condensers also gradually increases, thus creating an urgent need to improve the heat exchange capacity of steam condensers. Traditional steam condensers can be divided into shell-and-tube indirect condensers and hybrid condensers. Among them, shell-and-tube indirect condensers use an indirect heat exchange method where steam flows through the shell side and cooling water flows through the tube side, resulting in a lower overall heat transfer coefficient and a large volume. Hybrid condensers, on the other hand, use a phase change heat exchange method where steam and cooling water directly contact each other for condensation, resulting in a very high heat transfer coefficient and effectively reducing the condenser volume. Currently, hybrid condensers used in power plants have a water chamber located in the middle of the condenser to form a stable water film. Water is supplied to the interior of the water chamber by an external pump, and nozzles are installed on the water chamber. The function of the nozzles is to spray water to form a water film for efficient heat exchange with the steam.

[0003] However, since film formation in a mixing condenser involves ejecting a relatively high-speed water stream from nozzles, which impacts baffles on both sides of the nozzle to form a thin liquid film of a certain thickness, the velocity of the ejected water stream directly affects the quality of the liquid film. Too low a velocity will prevent film formation, while too high a velocity will disperse the film. If film formation cannot be sustained and stable, a good heat exchange effect cannot be achieved. Furthermore, the steam inside the condenser exhibits spatial distribution characteristics, making it difficult for the cooling water volume ejected from a single nozzle to efficiently match the cooling needs of different spaces within the condenser, thus hindering optimal cooling performance. Additionally, in a direct-mixing condensing system, the number of devices should be minimized; fewer devices result in a lower failure rate, ensuring that the pumps, as fluid machinery, operate at their designed operating speeds to improve system reliability. Simultaneously, the multi-stage regulating valves in a direct-mixing condensing system can interact, affecting the cooling water regulation speed.

[0004] Considering the above reasons, it is necessary to study a direct-mix condensing system for steam power systems, so as to significantly improve the reliability of the direct-mix condenser system and the speed of the cooling process, in order to adapt to the application scenarios of economical, small-scale power plants with high construction economic requirements and fast adjustment speed during use. Summary of the Invention

[0005] In response to one or more of the above-mentioned defects or improvement needs of the prior art, the present invention provides a direct-mix condenser system with dynamic coordinated control of two-stage regulating valves. By using a combination of two-stage regulating valves and combining the control principle of decoupled operation, interference during the regulation process of the two-stage regulating valves is avoided, thereby significantly improving the reliability of the direct-mix condenser system and the speed of the cooling process.

[0006] To achieve the above objectives, the present invention provides a direct-mix condenser system with dynamic coordinated control of two-stage regulating valves, including a condenser shell, a water chamber disposed therein, and a waste steam cooling space formed between the condenser shell and the water chamber. The water chamber is provided with a number of nozzles facing the exhaust steam cooling space at intervals, and the water chamber is divided into a number of partitions corresponding to the number of nozzles, so that each partition corresponds to a set of nozzles. The water inlet pipe connected to the water chamber is equipped with a water pump, a primary coarse adjustment valve and a secondary fine adjustment valve in sequence along the direction of water inlet. The secondary fine adjustment valves are arranged in parallel and the number of secondary fine adjustment valves corresponds to the number of zones. That is, each secondary fine adjustment valve is connected to the corresponding zone through a branch. The primary coarse adjustment valve is configured to perform pressure regulation, and the secondary fine adjustment valve is configured to perform flow regulation; the secondary fine adjustment valve is regulated using the same opening command. The primary coarse adjustment valve and the secondary fine adjustment valve are controlled by the following method: The input and output quantities of the primary coarse adjustment valve and the secondary fine adjustment valve are set, and the corresponding transfer function matrix between the input and output quantities is obtained. The target transfer function matrix between the output and input quantities after decoupling is set. The feedforward matrix is ​​obtained according to the inverse matrix of the transfer function matrix and the target transfer function matrix. The feedforward matrix is ​​applied to the direct-mix condenser system so that the partial pressure target value of the primary coarse adjustment valve is controlled only by the equivalent opening of the primary coarse adjustment valve, and the flow control target value of each zone of the secondary fine adjustment valve is controlled only by the equivalent opening of the secondary fine adjustment valve. A closed-loop controller is adopted, with the equivalent opening degree of the first-stage coarse adjustment valve and the equivalent opening degree of the second-stage fine adjustment valve as the control variables of the closed-loop controller, and the target value of the pressure of the first-stage coarse adjustment valve and the target value of the flow control of each zone of the second-stage fine adjustment valve as the controlled variables of the closed-loop controller, thereby realizing the decoupled control of the cooling water flow in the direct-mix condenser system.

[0007] As a further improvement of the present invention, the feedforward matrix is ​​obtained by the following method: Set the input values ​​for the primary coarse adjustment valve and the secondary fine adjustment valve. and output , , ,in This refers to the opening degree of the first-stage coarse adjustment valve. For the opening degree of the secondary fine-tuning valve, This is the target pressure distribution value for the primary coarse control valve. The target values ​​for flow control in each zone of the secondary fine-tuning valve; Set input amount With output The corresponding transfer functions between them yield the output. For input quantity transfer function matrix ; Define the target transfer function matrix between the output and input quantities after decoupling. ,in The target pressure value of the first-stage coarse adjustment valve Equivalent opening of the first-stage coarse control valve The transfer function, The target values ​​for flow control in each zone of the secondary fine-tuning valve. Equivalent opening of the secondary fine-tuning valve The transfer function; Solve the transfer function matrix The reverse formation Then the feedforward matrix can be obtained. .

[0008] As a further improvement of the present invention, in the target transfer function matrix, and It is either first-order or second-order inertia.

[0009] As a further improvement of the present invention, if there are n cooling load levels, the target value of the pressure distribution of the first-stage coarse adjustment valve is set to... The target flow control value for each zone of the secondary fine-tuning valve is The target values ​​for voltage distribution and flow control will be used as the controlled variables for each load condition.

[0010] As a further improvement of the present invention, the maximum and minimum values ​​of the nozzle flow rate are determined based on the nozzle pressure difference corresponding to each water chamber; Pressure difference of nozzle group in each water chamber The following formula must be satisfied:

[0011] In the formula, This represents the mass flow rate of water from a single nozzle. The flow resistance coefficient is... For flow area, For the density of cooling water, This is the lower limit of the pressure difference. This is the upper limit of the pressure difference; Pressure difference of nozzle assembly for At that time, the mass flow rate of water from a single nozzle At its minimum, the pressure difference of the nozzle assembly for At that time, the mass flow rate of water from a single nozzle It is at its maximum value.

[0012] As a further improvement of the present invention, the rated operating pressure of the water pump is greater than 1.1 to 1.5 times the rated operating pressure. , The expression is:

[0013] In the formula, This is the rated operating pressure drop of the nozzle; This refers to the rated operating pressure drop of the primary coarse regulating valve. This refers to the rated operating pressure drop of the secondary fine-tuning valve.

[0014] As a further improvement of the present invention, the water pump is a constant-speed centrifugal pump.

[0015] In summary, the technical solutions conceived by this invention have the following beneficial effects compared with the prior art: (1) The direct-mix condenser system of the present invention, which uses dynamic coordinated control of two-stage regulating valves, is based on the water chamber partitioning structure in the condenser. It utilizes a combination of two-stage regulating valves with regulating function, in which the first-stage coarse regulating valve undertakes the pressure distribution function, so that the second-stage fine regulating valve can accurately regulate the flow rate. Combined with the decoupled operation control principle, interference in the regulation process of the two-stage regulating valves is avoided, and the injection pressure of the nozzle is accurately controlled. The present invention adopts a highly efficient two-stage regulating valve coordinated control scheme and improves the speed of cooling water flow response through dynamic coordinated decoupled control process, so that the reliability of the direct-mix condenser system and the speed of the cooling process are significantly improved.

[0016] (2) In the direct mixing condensing system with dynamic coordinated control of two-stage regulating valves of the present invention, the first-stage coarse regulating valve and the second-stage fine regulating valve adopt decoupled control. The opening of the first-stage coarse regulating valve is used to adjust the pressure drop across the two ends of the second-stage fine regulating valve. The second-stage fine regulating valve is synchronously adjusted using the same opening command. Through the feedforward compensation design method of the present invention, the opening of the first-stage coarse regulating valve and the second-stage fine regulating valve and the control target are controlled by a single input and a single output, eliminating the interference in the adjustment process of the two-stage regulating valve and improving the adjustment speed.

[0017] (3) The direct mixing condensation system with dynamic coordinated control of two-stage regulating valves of the present invention can ensure that the water sprayed from the nozzle can effectively form a film under the minimum cooling flow condition and the water film is not torn under the maximum cooling condition, thus significantly improving the mixing cooling effect.

[0018] (4) The two-stage regulating valve dynamic coordinated control direct mixing condensing system of the present invention provides differentiated control target values ​​for different cooling loads, which can better match the needs of the cooling process and achieve better cooling efficiency.

[0019] (5) The direct mixing condensation system with dynamic coordinated control of two-stage regulating valves of the present invention adopts a fixed speed centrifugal pump and operates under rated design conditions. It eliminates the traditional speed regulation frequency conversion equipment, reduces the pump system volume, and improves pump efficiency by operating at a fixed speed under rated speed. The reliability of the water pump equipment can be improved without speed regulation. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a direct-mix condenser system with dynamic coordinated control of two-stage regulating valves according to an embodiment of the present invention. Figure 2 This is a schematic diagram showing the input, output, and interrelationships of a two-stage regulating valve system before decoupling, according to an embodiment of the present invention. Figure 3 This is a schematic diagram showing the input, output, and interrelationships of a two-stage regulating valve system after decoupling, according to an embodiment of the present invention. Figure 4 This is a schematic diagram illustrating the decoupling principle of a two-stage regulating valve system based on a feedforward compensator according to an embodiment of the present invention. Figure 5 This is a block diagram of the decoupling control of a two-stage regulating valve system based on a feedforward compensator, according to an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0024] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0025] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0026] As a preferred embodiment, the two-stage regulating valve dynamic coordinated control direct-mix condenser system of the present invention includes a condenser shell, a water chamber disposed therein, and a waste steam cooling space formed between the condenser shell and the water chamber. The water chamber is provided with a plurality of sets of nozzles spaced apart and facing the waste steam cooling space. The water chamber is further divided into several zones corresponding to the number of nozzles, such that each zone corresponds to a set of nozzles, and each set of nozzles includes at least one nozzle. A water pump, a primary coarse regulating valve, and a secondary fine regulating valve are sequentially arranged along the water inlet pipe connected to the water chamber. The fine regulating valves are arranged side-by-side, and the number of fine regulating valves corresponds to the number of zones; that is, each fine regulating valve is connected to its corresponding zone through a branch.

[0027] In one embodiment of the present invention, the nozzle flow rate range is determined based on the nozzle pressure difference corresponding to each water chamber, ensuring that the nozzle injection pressure is always in a reliable film-forming spray state. Specifically, the pressure difference of the nozzle group in each water chamber... That is, the pressure difference between the water chamber and the exhaust steam cooling space must satisfy the following formula:

[0028] In the formula, This represents the mass flow rate of water from a single nozzle. The flow resistance coefficient is... For flow area, For the density of cooling water, This is the lower limit of the pressure difference. This is the upper limit of the pressure difference.

[0029] It should be noted that, This is the lower limit of the pressure difference; below this value, the water sprayed from the nozzle will have difficulty forming a complete liquid film. This is the upper limit of the pressure difference; above this value, the liquid film will rupture under high pressure, preventing efficient heat exchange. The mass flow rate of water from a single nozzle can be calculated using the above formula. Pressure difference of nozzle group for At that time, the mass flow rate of water from a single nozzle At its minimum, the pressure difference of the nozzle assembly for At that time, the mass flow rate of water from a single nozzle It is at its maximum value.

[0030] This invention determines the maximum and minimum loads of the cooling water process by setting the limit value of the pressure difference between each nozzle in the water chamber. Based on the setting of the lower and upper limits of the pressure difference for each nozzle, this invention ensures that the water sprayed from the nozzles can effectively form a film under the minimum cooling flow condition, and that the water film is not torn under the maximum cooling flow condition, thus significantly improving the mixing cooling effect.

[0031] In one embodiment of the present invention, the water pump is preferably a constant-speed centrifugal pump, that is, it operates at the rated speed and is used in conjunction with a two-stage regulating valve to regulate the cooling water flow. This can not only meet the demand for large cooling water flow, but also eliminate the need for frequency conversion equipment in the traditional variable speed pump design method, reduce auxiliary equipment, reduce system size, and improve system reliability.

[0032] In one embodiment of the present invention, the rated operating pressure of the water pump is preferably greater than 1.1 to 1.5 times the rated operating pressure. , The expression is:

[0033] In the formula, This is the rated operating pressure drop of the nozzle; This refers to the rated operating pressure drop of the primary coarse regulating valve. This refers to the rated operating pressure drop of the secondary fine-tuning valve.

[0034] This invention, through the design of the rated operating pressure of the water pump, can ensure that the pump head meets the maximum operating head requirement and has a certain margin, while minimizing pump power consumption and pump size. Under the premise of ensuring functionality, the size is reduced and the economic cost of the system is lowered.

[0035] In one embodiment of the present invention, a primary coarse adjustment valve is configured to perform pressure regulation, and a secondary fine adjustment valve is configured to perform flow regulation. The primary coarse adjustment valve is used to adjust the distribution ratio of the system pressure drop, so that the opening range of the secondary fine adjustment valve is within a set threshold, which is further preferably [0.2, 0.9], thereby ensuring that the secondary fine adjustment valve has the conditions to accurately regulate the flow rate, so that the valve group of the secondary fine adjustment valve can accurately regulate the cooling water flow rate to each water chamber section, and ensure that the nozzles of each water chamber section spray out cooling water at the set flow rate under various operating conditions.

[0036] In one embodiment of the present invention, the two-stage fine-tuning valve is synchronously adjusted using the same opening command, which simplifies the control strategy and reduces the number of control modules in the case of multiple water chamber partitions, thus saving costs.

[0037] In one embodiment of the present invention, the primary coarse adjustment valve and the secondary fine adjustment valve are controlled by the following method: The input and output quantities of the primary coarse adjustment valve and the secondary fine adjustment valve are set, and the corresponding transfer function matrix between the input and output quantities is obtained. The target transfer function matrix between the output and input quantities after decoupling is set. The feedforward matrix is ​​obtained according to the inverse matrix of the transfer function matrix and the target transfer function matrix. The feedforward matrix is ​​applied to the direct-mix condenser system so that the partial pressure target value of the primary coarse adjustment valve is controlled only by the equivalent opening of the primary coarse adjustment valve, and the flow control target value of each zone of the secondary fine adjustment valve is controlled only by the equivalent opening of the secondary fine adjustment valve. A closed-loop controller is adopted, with the equivalent opening degree of the first-stage coarse adjustment valve and the equivalent opening degree of the second-stage fine adjustment valve as the control variables of the closed-loop controller, and the target value of the pressure of the first-stage coarse adjustment valve and the target value of the flow control of each zone of the second-stage fine adjustment valve as the controlled variables of the closed-loop controller, thereby realizing the decoupled control of the cooling water flow in the direct-mix condenser system.

[0038] In a specific embodiment, the primary coarse adjustment valve and the secondary fine adjustment valve are decoupled and controlled by the following method: like Figure 2 As shown, the input quantities (control quantities) of the primary coarse adjustment valve and the secondary fine adjustment valve are set. And output quantity (controlled quantity) ,Right now , ,in This is the opening degree of the first-stage coarse adjustment valve. For the opening degree of the secondary fine-tuning valve, This is the target pressure value of the first-stage coarse adjustment valve (i.e., the pressure difference across the first-stage coarse adjustment valve). The target values ​​for flow control in each zone of the secondary fine-tuning valve (i.e., the cooling water flow rate from the outlet of the secondary fine-tuning valve to each water chamber zone). The input quantity is obtained through model identification. With output The corresponding transfer functions between them yield the output. For input quantity transfer function matrix ; like Figure 3 As shown, based on the expected dynamic performance (such as settling time), the target transfer function matrix between the decoupled output and the equivalent input is set. ,in The target pressure value of the first-stage coarse adjustment valve Equivalent opening of the first-stage coarse control valve The transfer function, The target values ​​for flow control in each zone of the secondary fine-tuning valve. Equivalent opening of the secondary fine-tuning valve The transfer function; and Preferably, it is a first-order inertia, and at most a second-order inertia; Solve the transfer function matrix The reverse formation Then the feedforward matrix can be obtained. ; like Figure 4 As shown, the above feedforward matrix is ​​applied to the two-stage control valve system to be decoupled, so that the target value of the pressure division of the first-stage coarse control valve (i.e., the pressure difference across the first-stage coarse control valve) is achieved. Only affected by the equivalent opening of the first-stage coarse adjustment valve The control of the flow rate in each zone of the secondary fine-tuning valve (i.e., the cooling water flow rate from the outlet of the secondary fine-tuning valve to each water chamber zone) is determined. Only affected by the equivalent opening of the secondary fine-tuning valve Control.

[0039] Furthermore, such as Figure 5 As shown, the embodiment of the present invention employs a single-input single-output closed-loop controller. and The equivalent opening of the first-stage coarse adjustment valve is respectively used. Equivalent opening of the two-stage fine-tuning valve To control the quantity, the target value of the pressure distribution of the first-stage coarse adjustment valve (i.e., the pressure difference across the first-stage coarse adjustment valve) is used. The target values ​​for flow control in each zone of the secondary fine-tuning valve (i.e., the cooling water flow rate from the outlet of the secondary fine-tuning valve to each water chamber zone). As the controlled variable, it enables decoupled control of the cooling water flow rate of the direct-mix condenser.

[0040] It should also be noted that if there are n cooling load levels during the operation of the direct-mix condenser system, the target value for the partial pressure of the first-stage coarse adjustment valve should be set to... The target flow control value for each zone of the secondary fine-tuning valve is The above two sets of variable values ​​(target value of pressure distribution and target value of flow control in each zone) are used as the controlled variables of each load condition in the closed-loop controller.

[0041] This invention employs dynamic coordinated control of two-stage regulating valves: a primary coarse-adjusting valve for precise pressure regulation and a secondary fine-adjusting valve for precise flow regulation. To eliminate mutual interference between the two valve mechanisms, a decoupling control principle is used. This ensures that the pressure distribution across the primary coarse-adjusting valve is only affected by its equivalent opening, and the water flow to the corresponding zone from each secondary fine-adjusting valve is only affected by its equivalent opening. This eliminates mutual interference and improves regulation accuracy.

[0042] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A direct-mix condenser system with dynamic coordinated control of two-stage regulating valves, characterized in that, It includes the condenser shell, the water chamber inside it, and the exhaust steam cooling space formed between the two; The water chamber is provided with a number of nozzles facing the exhaust steam cooling space at intervals, and the water chamber is divided into a number of partitions corresponding to the number of nozzles, so that each partition corresponds to a set of nozzles. The water inlet pipe connected to the water chamber is equipped with a water pump, a primary coarse adjustment valve and a secondary fine adjustment valve in sequence along the direction of water inlet. The secondary fine adjustment valves are arranged in parallel and the number of secondary fine adjustment valves corresponds to the number of zones. That is, each secondary fine adjustment valve is connected to the corresponding zone through a branch. The primary coarse adjustment valve is configured to perform pressure regulation, and the secondary fine adjustment valve is configured to perform flow regulation; the secondary fine adjustment valve is regulated using the same opening command. The primary coarse adjustment valve and the secondary fine adjustment valve are controlled by the following method: The input and output quantities of the first-stage coarse adjustment valve and the second-stage fine adjustment valve are set, and the corresponding transfer function matrix between the input and output quantities is obtained. The target transfer function matrix between the output and input quantities after decoupling is set. The feedforward matrix is ​​obtained according to the inverse matrix of the transfer function matrix and the target transfer function matrix. The feedforward matrix is ​​applied to the direct-mix condenser system so that the partial pressure target value of the first-stage coarse adjustment valve is controlled only by the equivalent opening of the first-stage coarse adjustment valve, and the flow control target value of each zone of the second-stage fine adjustment valve is controlled only by the equivalent opening of the second-stage fine adjustment valve. A closed-loop controller is adopted, with the equivalent opening degree of the first-stage coarse adjustment valve and the equivalent opening degree of the second-stage fine adjustment valve as the control variables of the closed-loop controller, and the target value of the pressure of the first-stage coarse adjustment valve and the target value of the flow control of each zone of the second-stage fine adjustment valve as the controlled variables of the closed-loop controller, thereby realizing the decoupled control of the cooling water flow in the direct-mix condenser system.

2. The direct-mix condenser system with dynamic coordinated control of two-stage regulating valves according to claim 1, characterized in that, The feedforward matrix is ​​obtained through the following method: Set the input values ​​for the primary coarse adjustment valve and the secondary fine adjustment valve. and output , , ,in This refers to the opening degree of the first-stage coarse adjustment valve. For the opening degree of the secondary fine-tuning valve, This is the target pressure value for the first-stage coarse adjustment valve. The target values ​​for flow control in each zone of the secondary fine-tuning valve; Set input amount With output The corresponding transfer functions between them yield the output. For input quantity transfer function matrix ,in, The target pressure value of the first-stage coarse adjustment valve For the opening of the first-stage coarse adjustment valve The transfer function, The target pressure value of the first-stage coarse adjustment valve For the opening degree of the secondary fine-tuning valve The transfer function, The target values ​​for flow control in each zone of the secondary fine-tuning valve. For the opening of the first-stage coarse adjustment valve The transfer function, The target values ​​for flow control in each zone of the secondary fine-tuning valve. For the opening degree of the secondary fine-tuning valve The transfer function; Define the target transfer function matrix between the output and input quantities after decoupling. ,in The target pressure value of the first-stage coarse adjustment valve Equivalent opening of the first-stage coarse control valve The transfer function, The target values ​​for flow control in each zone of the secondary fine-tuning valve. Equivalent opening of the secondary fine-tuning valve The transfer function; Solve the transfer function matrix The reverse formation Then the feedforward matrix can be obtained. .

3. The direct-mix condenser system with dynamic coordinated control of two-stage regulating valves according to claim 2, characterized in that, In the target transfer function matrix and It is either first-order or second-order inertia.

4. The direct-mix condenser system with dynamic coordinated control of two-stage regulating valves according to claim 2 or 3, characterized in that, If there are n cooling load levels, then set the target pressure of the first-stage coarse adjustment valve to be [value missing]. The target flow control value for each zone of the secondary fine-tuning valve is The target values ​​for voltage distribution and flow control are used as the controlled variables for each load condition.

5. The direct-mix condenser system with dynamic coordinated control of two-stage regulating valves according to any one of claims 1-3, characterized in that, The maximum and minimum nozzle flow rates are determined based on the pressure difference between the nozzles corresponding to each water chamber. Pressure difference of nozzle group in each water chamber The following formula must be satisfied: In the formula, This represents the mass flow rate of water from a single nozzle. The flow resistance coefficient is... For flow area, For the density of cooling water, This is the lower limit of the pressure difference. This is the upper limit of the pressure difference; Pressure difference of nozzle assembly for At that time, the mass flow rate of water from a single nozzle At its minimum, the pressure difference of the nozzle assembly for At that time, the mass flow rate of water from a single nozzle It is at its maximum value.

6. The direct-mix condenser system with dynamic coordinated control of two-stage regulating valves according to any one of claims 1-3, characterized in that, The rated operating pressure of the water pump is greater than 1.1 to 1.5 times the rated operating pressure. , The expression is: In the formula, This is the rated operating pressure drop of the nozzle; This refers to the rated operating pressure drop of the primary coarse regulating valve. This refers to the rated operating pressure drop of the secondary fine-tuning valve.

7. The direct-mix condenser system with dynamic coordinated control of two-stage regulating valves according to any one of claims 1-3, characterized in that, The water pump is a constant-speed centrifugal pump.

Images