Multi-parameter dynamic closed-loop control system and method for water hammer suppression in dynamic water supply systems

Abstract

This invention discloses a multi-parameter dynamic closed-loop control system and method for suppressing water hammer in a power water supply system, relating to the technical field of power water supply systems with multiple pumps in parallel. It includes: multiple differential pressure acquisition devices, each corresponding to the inlet and outlet of a check valve at the outlet of multiple water pumps; and a speed regulating device connected to the multiple water pumps and the multiple differential pressure acquisition devices, configured to: acquire the inlet and outlet differential pressure signal of the check valve corresponding to any water pump that needs to be shut down; determine whether the inlet and outlet differential pressure signal is abnormal; if not, adjust the speed of the water pump according to the inlet and outlet differential pressure signal so that the inlet and outlet differential pressure of the check valve gradually decreases to 0 kPa according to a preset slope, and then quickly shut down the water pump. This invention, by dynamically controlling the inlet and outlet differential pressure of the check valve at the outlet of the water pump, can not only avoid water hammer but also prevent water pump stalling, which is beneficial for the long-term reliable operation of the equipment.

Description

Technical Field

[0001] This invention relates to the field of power water supply system technology with multiple pumps in parallel, and specifically to a multi-parameter dynamic closed-loop control system and method for suppressing water hammer in power water supply systems. Background Technology

[0002] The feedwater system for marine power boilers consists of feedwater pumps, check valves, and a control system. Feedwater pumps are classified as either constant-speed or variable-speed pumps. Variable-speed pumps can be electric or turbine feedwater pumps. In multi-pump parallel systems, combinations of multiple constant-speed pumps, multiple electric feedwater pumps, multiple turbine feedwater pumps, or mixed types of feedwater pumps are all used in marine boiler systems. Typically, a check valve is installed at the feedwater pump outlet to prevent backflow. When the feedwater pump outlet pressure reaches a certain value, the check valve opens, and the feedwater pump supplies water to the boiler normally.

[0003] When the feedwater pump is shut down, the sudden drop in pump outlet pressure can cause water hammer in the feedwater pipeline. Severe water hammer can cause significant damage to the feedwater system pipelines and related equipment, and can also cause system vibrations that are transmitted to the ship's hull, hindering noise control and mitigation. Common methods for suppressing water hammer in feedwater systems include: 1. Installing pressure-reducing valves; 2. Using buffer tanks or air chambers; 3. Controlling the opening and closing speed of check valves; and 4. Optimizing pipeline design.

[0004] However, in ship water supply systems, due to space constraints, modifications such as installing pressure reducing valves, adding buffer tanks or air chambers, and optimizing pipelines are time-consuming and costly. Furthermore, the commonly used check valves are mechanical components, making it difficult to actively control their opening and closing speeds. Some systems use a fixed acceleration active deceleration mode to shut down the feedwater pump, thereby reducing the closing speed of the check valve to avoid severe water hammer. This open-loop control method with fixed acceleration deceleration can still cause water hammer when the feedwater pump decelerates too quickly, while a slow deceleration results in the feedwater pump being stuck for a longer period, increasing the risk of cavitation and hindering long-term reliable operation of the equipment. Summary of the Invention

[0005] This invention provides a multi-parameter dynamic closed-loop control system and method for suppressing water hammer in power water supply systems. It can solve the technical problems of water hammer phenomenon occurring when the water pump decelerates too quickly, and water pump stalling for a long time when the water pump decelerates too slowly, which increases the risk of cavitation and is not conducive to the long-term reliable operation of the equipment.

[0006] In a first aspect, embodiments of the present invention provide a multi-parameter dynamic closed-loop control system for suppressing water hammer in a power feedwater system, comprising:

[0007] Multiple differential pressure acquisition devices are installed one-to-one at the inlet and outlet of multiple feedwater pump outlet check valves;

[0008] The speed regulating device, which is connected to multiple feedwater pumps and multiple differential pressure acquisition devices, is configured as follows:

[0009] Obtain the inlet and outlet pressure difference signal of the outlet check valve corresponding to any feedwater pump that needs to be shut down;

[0010] Determine if the inlet and outlet pressure difference signals are abnormal:

[0011] If not, adjust the speed of the water pump according to the inlet and outlet pressure difference signal so that the inlet and outlet pressure difference of the outlet check valve gradually decreases to 0 kPa according to the preset slope, and then quickly shut down the water pump.

[0012] In conjunction with the first aspect, in one embodiment, if not, then adjusting the speed of the water pump according to the inlet and outlet pressure difference signal to gradually reduce the inlet and outlet pressure difference of the outlet check valve to 0 kPa according to a preset slope, and then quickly shutting off the water pump, includes:

[0013] The pressure difference between the inlet and outlet of the outlet check valve is divided into multiple gradient control target ranges.

[0014] Multiple control cycles are set according to the control target range of multiple gradients. In each control cycle, the pressure difference between the inlet and outlet of the outlet check valve is reduced to the corresponding control target range by adjusting the speed of the water supply pump.

[0015] In conjunction with the first aspect, in one embodiment, the step of setting multiple control cycles corresponding to multiple control target ranges, and adjusting the feed water pump speed within each control cycle to reduce the inlet and outlet pressure difference of the outlet check valve to the corresponding control target range, includes:

[0016] If the pressure difference between the inlet and outlet of the outlet check valve exceeds the control target range after adjustment within a control cycle, the speed of the water supply pump is reduced, and the pressure difference enters the next control cycle after it falls within the control target range.

[0017] When the pressure difference between the inlet and outlet of the outlet check valve is adjusted to the control target range within a control cycle, the next control cycle begins.

[0018] If, within a control cycle, the pressure difference between the inlet and outlet of the outlet check valve is less than the control target range after adjustment, the speed of the water supply pump is increased, and the pressure difference enters the next control cycle after it falls within the control target range.

[0019] In conjunction with the first aspect, in one implementation, it includes:

[0020] The PID algorithm is used to reduce or increase the speed of the water supply pump.

[0021] In conjunction with the first aspect, in one implementation, after determining whether the inlet and outlet pressure difference signals are abnormal, the process includes:

[0022] If so, gradually reduce the output current of the water pump inverter, and when the output current of the water pump inverter reaches the preset current, quickly shut down the water pump.

[0023] Secondly, embodiments of the present invention provide a multi-parameter dynamic closed-loop control method for suppressing water hammer in a power feedwater system, comprising the following steps:

[0024] Obtain the inlet and outlet pressure difference signal of the outlet check valve corresponding to any feedwater pump that needs to be shut down;

[0025] Determine if the inlet and outlet pressure difference signals are abnormal:

[0026] If not, adjust the speed of the water pump according to the inlet and outlet pressure difference signal so that the inlet and outlet pressure difference of the outlet check valve gradually decreases to 0 kPa according to the preset slope, and then quickly shut down the water pump.

[0027] In conjunction with the second aspect, in one embodiment, if not, the water pump speed is adjusted according to the inlet and outlet pressure difference signal to gradually reduce the inlet and outlet pressure difference of the outlet check valve to 0 kPa according to a preset slope, and then the water pump is quickly shut off, including the following steps:

[0028] The pressure difference between the inlet and outlet of the outlet check valve is divided into multiple gradient control target ranges.

[0029] Multiple control cycles are set according to the control target range of multiple gradients. In each control cycle, the pressure difference between the inlet and outlet of the outlet check valve is reduced to the corresponding control target range by adjusting the speed of the water supply pump.

[0030] In conjunction with the second aspect, in one embodiment, the step of setting multiple control cycles corresponding to multiple control target ranges, and adjusting the speed of the water supply pump in each control cycle to reduce the inlet and outlet pressure difference of the outlet check valve to the corresponding control target range, includes the following steps:

[0031] If the pressure difference between the inlet and outlet of the outlet check valve exceeds the control target range after adjustment within a control cycle, the speed of the water supply pump is reduced, and the pressure difference enters the next control cycle after it falls within the control target range.

[0032] When the pressure difference between the inlet and outlet of the outlet check valve is adjusted to the control target range within a control cycle, the next control cycle begins.

[0033] If, within a control cycle, the pressure difference between the inlet and outlet of the outlet check valve is less than the control target range after adjustment, the speed of the water supply pump is increased, and the pressure difference enters the next control cycle after it falls within the control target range.

[0034] In conjunction with the second aspect, one implementation includes the following steps:

[0035] The PID algorithm is used to reduce or increase the speed of the water supply pump.

[0036] In conjunction with the second aspect, in one implementation, after determining whether the inlet and outlet pressure difference signal is abnormal, the following steps are included:

[0037] If so, gradually reduce the output current of the water pump inverter, and when the output current of the water pump inverter reaches the preset current, quickly shut down the water pump.

[0038] The beneficial effects of the technical solutions provided by the embodiments of the present invention include:

[0039] This invention discloses a multi-parameter dynamic closed-loop control system and method for suppressing water hammer in a power water supply system. The system includes: multiple differential pressure acquisition devices, each corresponding to the inlet and outlet of a plurality of feedwater pump outlet check valves; and a speed regulating device connected to the feedwater pumps and the differential pressure acquisition devices, configured to: acquire the inlet and outlet differential pressure signal of the outlet check valve corresponding to any feedwater pump that needs to be shut down; determine whether the inlet and outlet differential pressure signal is abnormal; if not, adjust the speed of the feedwater pump according to the inlet and outlet differential pressure signal so that the inlet and outlet differential pressure of the outlet check valve gradually decreases to 0 kPa according to a preset slope, and then quickly shut down the feedwater pump. This invention, by dynamically controlling the inlet and outlet differential pressure of the feedwater pump outlet check valve, can not only avoid water hammer but also prevent feedwater pump stalling, which is beneficial for the long-term reliable operation of the equipment. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic flowchart of the first embodiment of the multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to an embodiment of the present invention;

[0042] Figure 2This is a schematic flowchart of the second embodiment of the multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the multi-parameter dynamic closed-loop control system for suppressing water hammer in a power water supply system according to an embodiment of the present invention.

[0044] In the diagram: 10, speed regulating device; 20, feed water pump; 30, check valve; 40, differential pressure acquisition device; 50, feed water regulating valve; 60, boiler. Detailed Implementation

[0045] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] The existing method for suppressing water hammer in water supply systems is to decelerate and shut down the pump using a fixed acceleration deceleration mode. However, if the pump decelerates too quickly, water hammer will still occur. If the pump decelerates too slowly, the pump will be stuck in a stalled state for a longer period of time, increasing the risk of cavitation and hindering the long-term reliable operation of the equipment.

[0047] Example 1:

[0048] This invention provides a multi-parameter dynamic closed-loop control system for suppressing water hammer in a power water supply system. It adopts dynamic control of the inlet and outlet pressure difference of the check valve 30 at the outlet of the water pump 20, which can not only avoid water hammer, but also prevent the water pump from stalling, thus facilitating the long-term reliable operation of the equipment.

[0049] See Figure 1 , 3 As shown, the dynamic closed-loop control system for suppressing water hammer in the power water supply system includes: multiple differential pressure acquisition devices 40, which are correspondingly installed at the inlet and outlet of the outlet check valves 30 of multiple water supply pumps 20; a speed regulating device 10, which is connected to the multiple water supply pumps 20 and the multiple differential pressure acquisition devices 40, and is configured to: acquire the inlet and outlet differential pressure signal of the outlet check valve 30 corresponding to any water supply pump 20 that needs to be stopped; determine whether the inlet and outlet differential pressure signal is abnormal; if not, adjust the speed of the water supply pump 20 according to the inlet and outlet differential pressure signal so that the inlet and outlet differential pressure of the outlet check valve 30 gradually decreases to 0 kPa according to a preset slope, and then quickly shut down the water supply pump 20.

[0050] Multiple water pumps 20 are connected in parallel to form a water supply system to supply water to boiler 60.

[0051] After the boiler 60 is in normal operation, it needs to be continuously supplied with water through the water supply system, which consists of multiple water supply pumps 20 connected in parallel. Through parallel connection, the multiple water supply pumps 20 can complete the water supply task independently. When a water supply pump 20 in the system fails, other water supply pumps can be called to complete the water supply task without affecting the normal operation of the boiler 60.

[0052] Multiple check valves 30 are respectively installed at the outlet of multiple water supply pumps 20. The check valves 30 and the water supply pumps 20 are first connected in series and then in parallel to the water supply system.

[0053] The pressure sensors of the multiple differential pressure acquisition devices 40 are respectively installed at the inlet and outlet of the check valves 30 at the outlet of the multiple water pumps 20 to collect the differential pressure between the inlet and outlet of the check valves 30.

[0054] The speed regulation device 10 consists of a feedwater pump speed controller and a feedwater pump frequency converter, and is connected to each feedwater pump 20 and each differential pressure acquisition device 40 in the water supply system.

[0055] Since the opening of check valve 30 depends on the water flow direction and the pressure difference between its inlet and outlet, the check valve will only open after the water flow direction is determined and the pressure difference between its inlet and outlet reaches a certain value. When the pressure difference between the inlet and outlet of check valve 30 is less than or equal to 0 kPa, the pressure difference is insufficient to open the check valve, and check valve 30 remains closed.

[0056] When any feedwater pump 20 needs to be shut down, the corresponding differential pressure acquisition device 40 first acquires the inlet and outlet differential pressure of the check valve 30 at the outlet of the feedwater pump 20 to be shut down. The speed regulation device 10 acquires the inlet and outlet differential pressure signal of the check valve 30 at the outlet of the feedwater pump 20 to be shut down acquired by the differential pressure acquisition device 40, and analyzes the inlet and outlet differential pressure signal. If it is normal, the feedwater pump speed controller sends a command to the feedwater pump frequency converter to adjust the speed of the feedwater pump 20, so that the inlet and outlet differential pressure of the outlet check valve 30 gradually decreases to 0 kPa according to a preset slope. When the inlet and outlet differential pressure of the outlet check valve 30 is detected to be lower than or equal to 0 kPa, it indicates that the check valve 30 has been closed. At this time, quickly shutting down the feedwater pump 20 will not cause water hammer effect, and the speed of the feedwater pump 20 can be directly reduced until 0 speed.

[0057] Example 2:

[0058] Based on Example 1, the dynamic closed-loop control system for suppressing water hammer in the power water supply system of this invention uses an equal arithmetic method to divide the pressure difference between the inlet and outlet of the check valve 30 at the outlet of the water pump 20 into multiple control cycles, and gradually reduces the pressure difference until the pressure difference is zero, which can effectively prevent water hammer.

[0059] See Figure 3 As shown, the dynamic closed-loop control system for suppressing water hammer in the power water supply system, if not, adjusts the speed of the water supply pump 20 according to the inlet and outlet pressure difference signal to gradually reduce the inlet and outlet pressure difference of the outlet check valve 30 to 0 kPa according to a preset slope, and then quickly shuts off the water supply pump 20. This includes: dividing the inlet and outlet pressure difference of the outlet check valve 30 into multiple gradient control target ranges; setting multiple control cycles corresponding to the multiple gradient control target ranges; and adjusting the speed of the water supply pump 20 in each control cycle to reduce the inlet and outlet pressure difference of the outlet check valve 30 to the corresponding control target range.

[0060] The speed regulating device 10 analyzes the acquired inlet and outlet pressure difference signal of the check valve 30. If normal, the speed regulating device 10 divides the inlet and outlet pressure difference of the check valve 30 at the outlet of the water pump 20 from the initial pressure difference to 0 kPa into multiple control target ranges using an arithmetic progression. Each control target range corresponds to a control cycle. The shutdown process of the water pump 20 is divided into multiple steps according to the control cycle. In each control cycle, the water pump speed controller sends a command to the water pump frequency converter to adjust the speed of the water pump 20, so that the inlet and outlet pressure difference of the outlet check valve 30 reaches the control target range corresponding to each control cycle. The inlet and outlet pressure difference of the outlet check valve 30 is sequentially reduced according to the control cycle until the pressure difference is 0 kPa. At this point, the water pump 20 is quickly shut down.

[0061] Example 3:

[0062] Based on Example 2, in the power water supply system water hammer suppression multi-parameter dynamic closed-loop control system of this invention, if the inlet and outlet pressure difference of the outlet check valve 30 after regulation does not reach the corresponding control target range within a control cycle, the speed of the water supply pump 20 can be adjusted to make the inlet and outlet pressure difference of the outlet check valve 30 reach the corresponding control target range, so as not to affect the next control cycle.

[0063] See Figure 3As shown, the method of setting multiple control cycles corresponding to multiple gradient control target ranges, and adjusting the speed of the water supply pump 20 to reduce the inlet and outlet pressure difference of the outlet check valve 30 to the corresponding control target range within each control cycle, includes: when the inlet and outlet pressure difference of the outlet check valve 30 is greater than the control target range after adjustment within a control cycle, the speed of the water supply pump 20 is reduced, and the pressure difference is within the control target range before entering the next control cycle; when the inlet and outlet pressure difference of the outlet check valve 30 is within the control target range after adjustment within a control cycle, the next control cycle is entered; when the inlet and outlet pressure difference of the outlet check valve 30 is less than the control target range after adjustment within a control cycle, the speed of the water supply pump 20 is increased, and the pressure difference is within the control target range before entering the next control cycle.

[0064] The shutdown process of the water pump 20 is divided into multiple control cycles using an arithmetic progression. Within each control cycle, the water pump speed controller sends a command to the water pump inverter to adjust its output current, ensuring the pressure difference between the inlet and outlet of the outlet check valve 30 reaches the target range for that cycle. When the water pump speed controller detects that the adjusted pressure difference between the inlet and outlet of the outlet check valve 30 has not reached the target range, it analyzes the data and sends another command to the water pump inverter to adjust its output current, thus adjusting the speed of the water pump 20 until the pressure difference between the inlet and outlet of the outlet check valve 30 reaches the target range, and then proceeds to the next control cycle. When the water pump speed controller detects that the adjusted pressure difference between the inlet and outlet of the outlet check valve 30 has reached the target range, it proceeds to the next control cycle.

[0065] Example 4:

[0066] Based on Example 3, the dynamic closed-loop control system for suppressing water hammer in the power water supply system of this invention, when the pressure difference between the inlet and outlet of the outlet check valve 30 after regulation does not reach the corresponding control target range within a control cycle, uses a PID algorithm to reduce or increase the speed of the water supply pump 20 so that the pressure difference between the inlet and outlet of the outlet check valve 30 reaches the corresponding control target range, thereby not affecting the next control cycle.

[0067] See Figure 3 As shown, the dynamic closed-loop control system for water hammer suppression of the power water supply system includes: using a PID algorithm to reduce or increase the speed of the water supply pump 20.

[0068] The PID algorithm is a classic algorithm widely used in industrial control, robotics, automation, and other fields. Its core idea is to enable the system output to quickly and stably reach the target value through the synergistic effect of the proportional, integral, and derivative components.

[0069] Example 5:

[0070] Based on Example 1, the dynamic closed-loop control system for suppressing water hammer in the power water supply system of this embodiment of the invention, when the pressure difference signal between the inlet and outlet of the water pump outlet check valve is abnormal, the water pump speed controller sends a command to the water pump inverter to adjust the speed of the water pump 20, so that the output current of the water pump inverter gradually decreases to the critical output current value A1 of the water pump inverter when the pressure difference between the inlet and outlet is 0 kPa, and then the water pump 20 is quickly shut down to avoid water hammer phenomenon.

[0071] See Figure 2 , 3 As shown, after the dynamic closed-loop control system for water hammer suppression of the power water supply system determines whether the inlet and outlet pressure difference signals are abnormal, it includes: if so, gradually reducing the output current of the water supply pump inverter, and when the output current of the water supply pump inverter reaches the preset current, quickly shutting down the water supply pump 20.

[0072] First, manually adjust the water pump 20 to normal operation, ensuring the outlet check valve 30 of the water pump 20 is fully open. At this point, the pressure difference between the inlet and outlet of the check valve 30 at the outlet of the water pump 20 is much greater than 0 kPa. Then, manually and slowly reduce the speed of the water pump 20. When the pressure difference between the inlet and outlet of the check valve 30 at the outlet of the water pump 20 is 0 kPa, record the critical output current value A1 of the water pump inverter at this time, and use A1 as the preset current for stopping the water pump 20.

[0073] When water pump 20 is shut down, if an abnormal differential pressure signal occurs at the inlet and outlet of the check valve 30 at the outlet of water pump 20, the water pump speed controller sends a speed control permission signal to the water pump frequency converter. At this time, the water pump speed can be controlled by adjusting the output current of the water pump frequency converter until the water pump is shut down. The specific operation is as follows: the water pump control and regulation device sends a stop command to the corresponding water pump frequency converter; the water pump frequency converter slowly reduces the output current; when the output current of the water pump frequency converter is less than the preset current A1, it indicates that the check valve at the outlet of the water pump has been closed. Quickly shutting down the water pump will not cause water hammer, and water pump 20 can be quickly shut down.

[0074] Example 6:

[0075] The multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to an embodiment of the present invention includes the following steps:

[0076] Obtain the inlet and outlet pressure difference signal of the outlet check valve 30 corresponding to any water pump 20 that needs to be shut down;

[0077] Determine if the inlet and outlet pressure difference signals are abnormal:

[0078] If not, adjust the speed of the water pump 20 according to the inlet and outlet pressure difference signal so that the inlet and outlet pressure difference of the outlet check valve 30 gradually decreases to 0 kPa according to the preset slope, and then quickly shut down the water pump 20.

[0079] Example 7:

[0080] The multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to an embodiment of the present invention includes the following steps: If not, the water pump speed is adjusted according to the inlet and outlet pressure difference signal so that the inlet and outlet pressure difference of the outlet check valve is gradually reduced to 0 kPa according to a preset slope, and then the water pump is quickly shut off.

[0081] The pressure difference between the inlet and outlet of the outlet check valve is divided into multiple gradient control target ranges.

[0082] Multiple control cycles are set according to the control target range of multiple gradients. In each control cycle, the pressure difference between the inlet and outlet of the outlet check valve is reduced to the corresponding control target range by adjusting the speed of the water supply pump.

[0083] Example 8:

[0084] The multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to an embodiment of the present invention includes the following steps: Multiple control cycles are set according to multiple gradient control target ranges, and within each control cycle, the pressure difference between the inlet and outlet of the outlet check valve is reduced to the corresponding control target range by adjusting the speed of the water supply pump.

[0085] If the pressure difference between the inlet and outlet of the outlet check valve exceeds the control target range after adjustment within a control cycle, the speed of the water supply pump is reduced, and the pressure difference enters the next control cycle after it falls within the control target range.

[0086] When the pressure difference between the inlet and outlet of the outlet check valve is adjusted to the control target range within a control cycle, the next control cycle begins.

[0087] If, within a control cycle, the pressure difference between the inlet and outlet of the outlet check valve is less than the control target range after adjustment, the speed of the water supply pump is increased, and the pressure difference enters the next control cycle after it falls within the control target range.

[0088] Example 9:

[0089] The multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to an embodiment of the present invention includes the following steps:

[0090] The PID algorithm is used to reduce or increase the speed of the water supply pump.

[0091] Example 10:

[0092] The multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to an embodiment of the present invention includes the following steps after determining whether the inlet and outlet pressure difference signals are abnormal:

[0093] If so, gradually reduce the output current of the water pump inverter, and when the output current of the water pump inverter reaches the preset current, quickly shut down the water pump.

[0094] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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 between two elements. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0095] It should be noted that in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0096] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the invention herein.

Claims

1. A multi-parameter dynamic closed-loop control system for suppressing water hammer in a power water supply system, characterized in that, It includes: Multiple differential pressure acquisition devices are installed one-to-one at the inlet and outlet of multiple feedwater pump outlet check valves; The speed regulating device, which is connected to multiple feedwater pumps and multiple differential pressure acquisition devices, is configured as follows: Obtain the inlet and outlet pressure difference signal of the outlet check valve corresponding to any feedwater pump that needs to be shut down; Determine if the inlet and outlet pressure difference signals are abnormal: If not, the inlet and outlet pressure difference of the outlet check valve is divided into multiple gradient control target ranges. Multiple control cycles are set according to the control target range of multiple gradients. In each control cycle, the pressure difference between the inlet and outlet of the outlet check valve is reduced to the corresponding control target range by adjusting the speed of the water supply pump. If, within a control cycle, the inlet and outlet pressure difference of the outlet check valve, after adjustment, exceeds the control target range, the speed of the feedwater pump is reduced. Once the pressure difference falls within the control target range, the next control cycle begins. If, within a control cycle, the inlet and outlet pressure difference of the outlet check valve, after adjustment, falls within the control target range, the next control cycle begins. If, within a control cycle, the inlet and outlet pressure difference of the outlet check valve, after adjustment, falls below the control target range, the speed of the feedwater pump is increased. Once the pressure difference falls within the control target range, the next control cycle begins, causing the inlet and outlet pressure difference of the outlet check valve to gradually decrease to 0 kPa according to a preset slope, and then the feedwater pump is quickly shut off.

2. The multi-parameter dynamic closed-loop control system for suppressing water hammer in a power water supply system according to claim 1, characterized in that, include: The PID algorithm is used to reduce or increase the speed of the water supply pump.

3. The multi-parameter dynamic closed-loop control system for suppressing water hammer in a power water supply system according to claim 1, characterized in that, After determining whether the inlet and outlet pressure difference signals are abnormal, the process includes: If so, gradually reduce the output current of the water pump inverter, and when the output current of the water pump inverter reaches the preset current, quickly shut down the water pump.

4. A multi-parameter dynamic closed-loop control method for suppressing water hammer in a power feedwater system, using the multi-parameter dynamic closed-loop control system for suppressing water hammer in a power feedwater system as described in claim 1, characterized in that... Includes the following steps: Obtain the inlet and outlet pressure difference signal of the outlet check valve corresponding to any feedwater pump that needs to be shut down; Determine if the inlet and outlet pressure difference signals are abnormal: If not, the inlet and outlet pressure difference of the outlet check valve is divided into multiple gradient control target ranges. Multiple control cycles are set according to the control target range of multiple gradients. In each control cycle, the pressure difference between the inlet and outlet of the outlet check valve is reduced to the corresponding control target range by adjusting the speed of the water supply pump. If, within a control cycle, the inlet and outlet pressure difference of the outlet check valve, after adjustment, exceeds the control target range, the speed of the feedwater pump is reduced, and the pressure difference returns to the control target range before entering the next control cycle. If, within a control cycle, the inlet and outlet pressure difference of the outlet check valve, after adjustment, falls within the control target range, the next control cycle begins. If, within a control cycle, the inlet and outlet pressure difference of the outlet check valve, after adjustment, falls below the control target range, the speed of the feedwater pump is increased, and the pressure difference returns to the control target range before entering the next control cycle. The inlet and outlet pressure difference of the outlet check valve is gradually reduced to 0 kPa according to a preset slope, and then the feedwater pump is quickly shut off.

5. The multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to claim 4, characterized in that, Includes the following steps: The PID algorithm is used to reduce or increase the speed of the water supply pump.

6. The multi-parameter dynamic closed-loop control method for suppressing water hammer in a power water supply system according to claim 4, characterized in that, After determining whether the inlet and outlet pressure difference signals are abnormal, the following steps are included: If so, gradually reduce the output current of the water pump inverter, and when the output current of the water pump inverter reaches the preset current, quickly shut down the water pump.

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