WO2024251033A1 - Seawater cooling device and seawater pump control method - Google Patents

Abstract

A seawater cooling device and a seawater pump control method. The seawater cooling device is characterized in that the seawater cooling device comprises seawater pumps, seawater filters, seawater heat exchangers, devices to be cooled and a seawater pump control system, wherein a plurality of seawater pumps are provided, and water supply ends of the seawater pumps are respectively connected to seawater inlets of a plurality of seawater heat exchangers by means of the seawater filters; each seawater heat exchanger further comprises a fresh water inlet and a fresh water outlet, and is configured to realize the circulation of fresh water in the seawater heat exchanger and the heat exchange between seawater and fresh water; the fresh water inlet and the fresh water outlet are respectively connected to a water drainage port and a water inlet of a cooling system in each of a plurality of devices to be cooled, such that cooling of the interiors of the devices to be cooled using the fresh water is realized; and the seawater pump control system collects data from sensors on the seawater pumps, the seawater filters, the seawater heat exchangers and the devices to be cooled, and controls states of the seawater pumps on the basis of the data. The present invention ensures effective heat exchange which is performed by a system on air conditioners and other apparatuses to be cooled.

Description

A seawater cooling device and a seawater pump control method

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese patent application No. 202310663232.4 filed with the Chinese Patent Office on June 6, 2023, entitled “A seawater cooling device and seawater pump control method”, the entire contents of which are incorporated by reference into this application.

Technical Field

The present invention relates to the field of seawater cooling, and more specifically, to a seawater cooling device and a seawater pump control method.

Background Art

At present, with the continuous development of High Voltage Direct Current Transmission (HVDC) technology, its ultra-long distance and large capacity transmission, low cost and low loss have made it widely used in my country and other countries. In order to effectively solve the problem of large capacity and long distance of offshore wind farms, it is imperative to introduce high voltage direct current transmission technology into offshore wind farms and build converter stations at sea.

The converter station generates a lot of heat. In order to ensure the continuous large-scale operation of the converter station, a reliable cooling system is required. In the prior art, the cooling system of the converter station is usually realized through water circulation. However, the location of the offshore converter station makes it difficult to obtain more fresh water resources, and directly using seawater cooling is easy to cause the cooled equipment or cooling system to be corroded by seawater, reducing the service life.

Background technology document CN115060105A discloses a seawater heat exchange system, its control device and ship. In the document, the seawater in the seawater heat exchanger is configured to cool the fresh water in the freshwater heat exchanger. In addition, the seawater pump, as a seawater driving device in the seawater cooling device, is an important part of the device. Its safe and stable operation can effectively ensure the cooling requirements of the cooling system and ensure the safe and stable operation of the cooled device.

However, there are still some problems in the prior art. For example, after working for a long time, the seawater pump in the seawater heat exchange system is usually prone to temporary equipment failure due to factors such as temperature. If the status of the seawater pump cannot be monitored in time, the heat exchange efficiency of the seawater may be reduced, making it impossible for the device to be cooled to exchange heat.

In view of the above problems, a seawater cooling device and a seawater pump control method are urgently needed.

Summary of the invention

In order to solve the deficiencies in the prior art, the present invention provides a seawater cooling device and a seawater pump control method, which realizes cooling of the device to be cooled by jointly setting up a seawater pump, a seawater filter, a seawater heat exchanger, a device to be cooled and a seawater pump control system.

The present invention adopts the following technical solution.

A first aspect of the present invention relates to a seawater cooling device, which includes a seawater pump, a seawater filter, a seawater heat exchanger, a device to be cooled, and a seawater pump control system; wherein there are multiple seawater pumps, and the water delivery ends of the seawater pumps are respectively connected to the seawater inlets of multiple seawater heat exchangers through the seawater filters; the seawater heat exchanger also includes a freshwater inlet and a freshwater outlet, which are configured to realize the circulation of fresh water in the seawater heat exchanger and the heat exchange between seawater and fresh water; the freshwater inlet and the freshwater outlet are respectively connected to the drain outlet and the water inlet of the cooling system in the multiple devices to be cooled, so as to realize the internal cooling of the devices to be cooled by fresh water; the seawater pump control system collects data from sensors on the seawater pump, the seawater filter, the seawater heat exchanger, and the devices to be cooled, and realizes the state control of the seawater pump based on the data.

Optionally, the seawater pump includes a main seawater pump and a backup seawater pump; wherein each seawater pump is provided with a start-stop controller, and the start-stop controller realizes start-stop control of the seawater pump based on the seawater pump control system; when the seawater pump control system is turned on, the start-stop controller of the main seawater pump is in the start state by default, and the start-stop controller of the backup seawater pump is in the stop state by default.

Optionally, a pressure sensor is also provided on the water delivery end of the seawater pump, and the pressure sensor is configured to detect the pressure of the water delivery end of the seawater pump and transmit the detection result to the seawater pump control system; when the detection result is lower than the protection set value, other seawater pumps that are in the shutdown state are started.

Optionally, a temperature sensor and a flow meter are respectively provided on the seawater inlet and the water outlet of the seawater heat exchanger. The temperature sensor and the flow meter are configured to realize statistics of the heat exchange amount of the seawater heat exchanger per unit time, and transmit the statistical results to the seawater pump control system; the seawater pump control system simultaneously collects the heat dissipation of the cooled device per unit time, And by comparing the heat exchange and heat dissipation, the start and stop control of the seawater pump is achieved.

Optionally, the seawater heat exchanger is a non-contact plate heat exchanger.

Optionally, the seawater pumps include three main seawater pumps and one standby seawater pump; and at every moment, three seawater pumps are in operation.

Optionally, the device further comprises a leak detection tank, the water inlet of the leak detection tank is respectively connected to the water outlet of the seawater filter and the water outlet of the seawater heat exchanger through drainage pipes, and a liquid level sensor is also arranged inside the leak detection tank.

Optionally, the liquid level sensor is used to detect the liquid level inside the leak detection tank when the seawater pump is shut down; when the liquid level inside the leak detection tank changes by more than a set value in a short period of time, a seawater leakage warning is issued through the seawater pump control system.

Optionally, the leak detection tank is integrally formed with the drainage pipe, the leak detection tank is arranged at the end of the drainage pipe, and the leak detection tank is above the liquid level of the seawater pump, the seawater filter, and the seawater heat exchanger.

Optionally, the drainage pipe includes at least one section of vertically arranged pipeline on a side close to the leak detection tank, so that the leak detection tank is above the liquid level of the seawater pump, the seawater filter and the seawater heat exchanger.

The second aspect of the present invention relates to a seawater pump control method, which is implemented by the seawater cooling device in the first aspect of the present invention; and the method includes the following steps: step 1, collecting the current heat dissipation of the device to be cooled in the seawater cooling device, and estimating the current heat exchange capacity of the seawater pump based on the current heat dissipation; step 2, calculating the number of seawater pumps that should be enabled at present based on the rated heat exchange capacity and current heat exchange capacity of each seawater pump; step 3, controlling the start and stop of the seawater pump based on the number.

Optionally, the seawater pump control system also adopts a power supply switching method to realize power supply to the seawater pump.

Optionally, the seawater pump control system uses a dual power supply switching rear bus to supply power to the seawater pump.

Optionally, the control system collects the operating time of the seawater pump. If the operating time of the current seawater pump exceeds a set threshold, it determines whether there is an idle seawater pump in the seawater cooling device. If so, the current seawater pump is shut down and the idle seawater pump is started.

Optionally, if the seawater pump has an overheat alarm, a soft starter alarm, or a power supply alarm, the control system switches the operating state of the seawater pump.

The beneficial effect of the present invention is that, compared with the prior art, the present invention is a seawater cooling device, which realizes cooling of the device to be cooled by the joint arrangement of a seawater pump, a seawater filter, a seawater heat exchanger, the device to be cooled and a seawater pump control system. The present invention is effective and reliable, and realizes accurate monitoring of the operation of the system by arranging various sensors on various components, thereby ensuring effective heat exchange of the system for the air conditioning device to be cooled.

The beneficial effects of the present invention also include:

1. The present invention sets various sensors such as temperature sensors, pressure sensors, flow meters, etc. at reasonable positions of various equipment. Through comprehensive analysis and control, it realizes the monitoring and elimination of various faults. By reasonably controlling the opening, switching and shutting down of the seawater pump, accurate and reasonable heat exchange is achieved.

2. The method of the present invention saves the control energy consumption of the seawater pump, increases the service life of the seawater pump, simplifies the function of the seawater pump, and reduces the cost of the seawater pump.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of equipment connection of a seawater cooling device according to the present invention;

FIG2 is a schematic diagram of the steps of a seawater pump control method of the present invention;

FIG. 3 is a schematic diagram of a power supply for a seawater pump in a seawater cooling device according to the present invention.

DETAILED DESCRIPTION

In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in the present invention are only embodiments of a part of the present invention, not all embodiments. Based on the spirit of the present invention, all other embodiments not recorded in the present invention obtained by ordinary technicians in this field according to the embodiments recorded in the present invention without making creative work should belong to the protection scope of the present invention.

FIG1 is a schematic diagram of equipment connection of a seawater cooling device of the present invention. As shown in FIG1, in a first aspect of the present invention, A seawater cooling device is disclosed, comprising a seawater pump, a seawater filter, a seawater heat exchanger, a device to be cooled and a seawater pump control system; wherein there are multiple seawater pumps, and the water supply ends of the seawater pumps are respectively connected to the seawater water inlets of multiple seawater heat exchangers through the seawater filters; the seawater heat exchanger also comprises a freshwater inlet and a freshwater outlet, which are configured to realize the circulation of fresh water in the seawater heat exchanger and the heat exchange between seawater and fresh water; the freshwater inlet and the freshwater outlet are respectively connected to the drain outlet and the water inlet of the cooling system in the multiple devices to be cooled, so as to realize the internal cooling of the devices to be cooled by fresh water; the seawater pump control system collects data from sensors on the seawater pump, the seawater filter, the seawater heat exchanger and the devices to be cooled, and realizes the state control of the seawater pump based on the data.

It is understandable that the various devices in the seawater cooling device of the present invention are interconnected, wherein the number of seawater pumps and the number of devices to be cooled can be reasonably set according to actual needs. It should be specially noted that the devices to be cooled in the present invention may not only include those traditional devices that require heat exchange and cooling, but also devices such as air conditioners that require precise temperature control. In the present invention, there are many ways to cool down and control the temperature of devices such as air conditioners, for example, it can be achieved by adjusting the speed of a seawater pump, or by controlling the flow rate of the seawater inlet and outlet in a seawater heat exchanger, and so on.

Considering that the seawater pump in the prior art also needs to be temperature controlled and paused during long-term operation, a relatively sufficient number of seawater pumps can be provided in the present invention.

The device may also include multiple seawater filters, such as one for use and one for backup, three for use and one for backup, etc., so as to achieve continuous filtration of impurities in the seawater. In one embodiment of the present invention, the seawater filter may be provided with an automatic cleaning function.

Optionally, the seawater pump includes a main seawater pump and a backup seawater pump; wherein each seawater pump is provided with a start-stop controller, and the start-stop controller realizes start-stop control of the seawater pump based on the seawater pump control system; when the seawater pump control system is turned on, the start-stop controller of the main seawater pump is in the start state by default, and the start-stop controller of the backup seawater pump is in the stop state by default.

In one embodiment of the present invention, three main seawater pumps and one standby seawater pump are provided. Each seawater pump is started and stopped in rotation. The first activated one is stopped first after reaching a preset time, and the last activated one is stopped last. Thus, three seawater pumps are in operation and one seawater pump is in rest state at any time through rotation training. Specifically, the seawater pump receives control information provided by the seawater pump control system, thereby realizing the control of starting and stopping.

Optionally, a pressure sensor is also provided on the water delivery end of the seawater pump, and the pressure sensor is configured to detect the pressure of the water delivery end of the seawater pump and transmit the detection result to the seawater pump control system; when the detection result is lower than the protection set value, other seawater pumps that are in the shutdown state are started.

It is understandable that a pressure sensor is provided on the water delivery end of the seawater pump, and the pressure sensor can detect the pressure of the water delivery end of the seawater pump. The seawater pump control system can control the seawater pump or other equipment according to the data in the pressure sensor.

Optionally, a temperature sensor and a flow meter are respectively provided on the seawater inlet and outlet of the seawater heat exchanger, and the temperature sensor and the flow meter are configured to realize statistics of the heat exchange of the seawater heat exchanger per unit time, and transmit the statistical results to the seawater pump control system; the seawater pump control system simultaneously collects the heat dissipation of the cooled device per unit time, and realizes the start and stop control of the seawater pump by comparing the heat exchange and heat dissipation.

It is understandable that the temperature sensor and flow meter are also provided on the seawater inlet and outlet of the seawater heat exchanger in the present invention. Since the temperature difference and flow are measured, the actual heat exchange of the seawater heat exchanger per unit time can be obtained. Therefore, in this way, the method can provide the corresponding operating efficiency or start-stop number of the seawater pump according to the heat dissipation required by the device to be cooled.

Optionally, the seawater heat exchanger is a non-contact plate heat exchanger. The plate heat exchanger is a new type of efficient and compact heat exchanger that has been developed and widely used in recent decades. It is composed of a series of parallel thin metal plates with corrugated surfaces stacked on top of each other, while the spiral plate heat exchanger is more compact and has better heat transfer performance.

Optionally, the device also includes a leak detection tank, a water inlet of which is respectively connected to the water outlet of the seawater filter and the water outlet of the seawater heat exchanger through drainage pipes; and a liquid level sensor is also provided inside the leak detection tank, configured to detect the liquid level inside the leak detection tank when the seawater pump is shut down; when the liquid level inside the leak detection tank changes by more than a set value in a short period of time, a seawater leakage warning is issued through the seawater pump control system.

It should be noted that each device in the present invention can be made of super duplex steel material, which can prevent the device parts from being corroded by seawater during long-term contact with seawater, so it has excellent performance. In addition, there are a large number of connection points between various parts, seawater pipes and equipment of various equipment such as seawater pumps, seawater filters, seawater heat exchangers, etc. Some of these connection points are made in the form of flanges, and some are realized in the form of bolt connection points. When the bolts are loose, it may cause the connection between the equipment to be not tight and reliable enough, and there is a possibility of water leakage. Therefore, the present invention is provided with a leak detection tank to prevent the problem of water leakage in the entire device and being unable to detect it. It is easy to think that when the seawater cooling device is shut down, the leak detection tank can easily determine whether there is a seawater leak inside the seawater cooling device by monitoring the liquid level position of the seawater, thereby ensuring the safety of the entire cooling device, preventing the ineffective operation of the seawater pump, and extending the service life of the seawater pump.

In the present invention, when the entire device is in an intermittent shutdown state, the leak detection tank can be used to perform an overall inspection of the device state. In order to achieve such inspection, the present invention sets the internal seawater pipelines of the leak detection tank, the seawater pump in the shutdown state, the seawater filter, the seawater heat exchanger and other equipment to be connected and connected to the outside only through the liquid level of the leak detection tank.

In this way, if any device leaks, the liquid level in the leak detection tank will change significantly in a short period of time. At this time, a leak warning can be issued based on the liquid level sensor inside the leak detection tank. If the liquid level inside the leak detection tank does not change significantly in a short period of time, it means that the leak detection tank may only have normal evaporation of seawater, and there is no leakage in the seawater internal connecting pipeline.

Optionally, the leak detection tank is integrally formed with the drainage pipe, the leak detection tank is arranged at the end of the drainage pipe, and the drainage pipe includes at least one section of vertically arranged pipeline on the side close to the leak detection tank, so that the leak detection tank is above the liquid level of the seawater pump, seawater filter and seawater heat exchanger.

In the prior art, the control of the seawater pump is mainly achieved through the rotation speed. In order to ensure the cooling performance of seawater on fresh water, the rotation speed of the seawater pump usually needs to be set relatively high so that the seawater pump can fully cool the fresh water. This technology makes the seawater heat exchanger only able to ensure heat exchange for some devices to be cooled that do not require high temperature accuracy. If the device to be cooled is an air conditioner or other equipment that requires accurate temperature control and adjustment, the seawater pump in the prior art needs to accurately and frequently adjust its rotation speed. This causes the seawater pump to consume a lot of energy in the process of frequently adjusting the rotation speed, and also reduces the service life of the seawater pump, increases the number of seawater pump speed adjustment gears, and increases the cost of the seawater pump.

In the present invention, the leak detection tank can be integrally formed with the drainage pipe, and the leak detection tank can be cylindrical or other similar shapes, but is widened at the end of the drainage pipe. In addition, considering that the leak detection tank in the present invention can also be directly connected to the water outlet of the seawater filter, this arrangement also allows the leak detection tank to directly receive the excess seawater provided by the seawater pump and cannot be fully used by the seawater heat exchanger.

Therefore, when the seawater heat exchanger is used to control the temperature of equipment such as air conditioners that require precise temperature control, the seawater heat exchanger and other equipment can regulate the amount of seawater entering the equipment, and directly discharge the excess seawater through the leak detection tank. As a result, the seawater pump no longer needs to adjust the water intake through precise speed control, and can still meet the temperature control requirements of precise equipment such as air conditioners. Therefore, in the present invention, due to the addition of the leak detection tank, precise temperature control equipment such as air conditioners can also be used as one of the devices to be cooled to achieve joint regulation. At the same time, this method can avoid frequent adjustment of the speed of the seawater pump, save the control energy consumption of the seawater pump, increase the service life of the seawater pump, simplify the function of the seawater pump, and reduce the cost of the seawater pump.

Figure 2 is a schematic diagram of the steps of a seawater pump control method of the present invention. As shown in Figure 2, the second aspect of the present invention relates to a seawater pump control method, which is implemented by the seawater cooling device in the first aspect of the present invention; and the method includes the following steps: Step 1, collecting the current heat dissipation of the device to be cooled in the seawater cooling device, and estimating the current heat exchange of the seawater pump based on the current heat dissipation; Step 2, calculating the number of seawater pumps that should be enabled at present based on the rated heat exchange and current heat exchange of each seawater pump; Step 3, starting and stopping the seawater pump based on the number.

It is easy to understand that in the method of the present invention, the currently required heat exchange amount can be estimated by the current heat dissipation of the device to be cooled in the device to be cooled, and after the heat exchange amount is determined, the required number of seawater pumps can be estimated according to the rated heat exchange amount of each seawater pump. Through this simple method, the present invention can realize the start and stop control of the seawater pump.

Specifically, for the seawater heat exchanger, the seawater side of each group of plate heat exchangers includes the inlet and outlet temperatures and flow rates, so the actual heat dissipation can be calculated as:

Where q is the circulation flow of seawater, which can be measured by a flow meter.

C is the specific heat capacity of seawater, which is set to 4.08 kJ/(kg·℃) in the present invention.

Δt is the temperature difference achieved by heat exchange between the water inlet and the water outlet, which can be measured by a temperature sensor.

By using the above parameters, it is possible to calculate the heat transfer achieved by seawater in the seawater heat exchanger, that is, the heat transfer amount Q of the seawater heat exchanger.

Optionally, the seawater pump control system also uses a power switching method to power the seawater pump. Figure 3 is a schematic diagram of the power supply of a seawater pump in a seawater cooling device of the present invention. As shown in Figure 3, the seawater pump in the present invention can be started in two different ways: soft start and power frequency start. Both starting methods use the busbar after the dual power supply is switched to realize the connection between the seawater pump and the power supply. In this way, when a single incoming line fails, it will not affect the stable operation of the seawater pump.

Optionally, the control system collects the operating time of the seawater pump. If the operating time of the current seawater pump exceeds a set threshold, it determines whether there is an idle seawater pump in the seawater cooling device. If so, the current seawater pump is shut down and the idle seawater pump is started.

The seawater pump control system of the present invention can realize the collection of sensor data and the control of various devices in various ways. In one embodiment of the present invention, the seawater pump can be controlled by PLC (Programmable Logic Controller) and other methods.

As shown in the embodiment of the present invention in FIG. 1 , there are four seawater pumps, three in use and one in standby, and a single seawater pump is powered by switching two AC inlet dual power supplies, and the number of seawater pumps in operation is determined according to the heat dissipation of the system. When the water inlet temperature of the device to be cooled and the newly added air conditioning system is high, the three seawater pumps can be automatically started to cool down the device to be cooled and the air conditioner and perform heat exchange. When the device to be cooled and the air conditioner are in operation, the seawater pump is usually not completely disabled, but the number is adjusted to ensure that it can meet the heat exchange performance of various types of equipment.

In the present invention, the seawater pump can be switched regularly or when a fault occurs. Specifically, the seawater pump can realize the periodic switching function by switching the period, wherein the length of the period can be set. For example, after the #1 seawater pump has been running continuously without fault for 12 hours, the seawater pump control system in the present invention can start the seawater pump automatic switching logic to ensure that the standby seawater pump is put into soft start operation while the #1 main seawater pump is stopped.

In addition, when the seawater pump has an overheat alarm, soft starter alarm, or power supply alarm, the operating state of the seawater pump can also be switched, such as switching from the main pump to the standby pump. In addition, a pressure sensor is installed at the outlet of each seawater pump. When the pressure sensor measurement value is lower than the protection set value, it switches to the standby pump soft start operation.

In the above switching process, if the current seawater pump fails to switch to the standby pump and there is no other available standby pump, it is also possible to switch back to the original operating seawater pump.

The seawater cooling device in the present invention can ensure the cooling requirements of the entire offshore DC converter station. Since the power consumption of the seawater pump is relatively large, the control method can accurately control the number of seawater pump starts and stops by the heat generated by the device to be cooled, thereby reducing power consumption; through timed switching, polling control of the seawater pump is realized to increase the service life of the seawater pump; through fault switching, the reliability of the seawater cooling device is increased.

The beneficial effect of the present invention is that, compared with the prior art, the present invention is a seawater cooling device, which realizes cooling of the device to be cooled by the joint arrangement of a seawater pump, a seawater filter, a seawater heat exchanger, the device to be cooled and a seawater pump control system. The present invention is effective and reliable, and realizes accurate monitoring of the operation of the system by arranging various sensors on various components, thereby ensuring effective heat exchange of the system for the air conditioning device to be cooled.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Industrial Applicability

The present application sets various sensors such as temperature sensors, pressure sensors, flow meters, etc. at reasonable positions of various devices in the seawater cooling device. Through comprehensive analysis and control, various faults are monitored and eliminated. By reasonably controlling the opening, switching and shutting down of the seawater pump, accurate and reasonable heat exchange is achieved. The seawater pump control system collects data from sensors on the seawater pump, seawater filter, seawater heat exchanger, and device to be cooled, and realizes state control of the seawater pump based on the data. The seawater pump control method provided by the present application saves the control energy consumption of the seawater pump, increases the service life of the seawater pump, simplifies the function of the seawater pump, reduces the cost of the seawater pump, and has better practicality.

Claims (15)

A seawater cooling device, characterized in that: The device comprises a seawater pump, a seawater filter, a seawater heat exchanger, a device to be cooled and a seawater pump control system; wherein, There are multiple seawater pumps, and the water supply ends of the seawater pumps are connected to the seawater inlets of the multiple seawater heat exchangers through the seawater filters respectively; The seawater heat exchanger also includes a fresh water inlet and a fresh water outlet, which are configured to realize the circulation of fresh water in the seawater heat exchanger and the heat exchange between seawater and fresh water; The fresh water inlet and the fresh water outlet are respectively connected to the drain port and the water inlet of the cooling system in the plurality of components to be cooled, so as to realize the internal cooling of the components to be cooled by the fresh water; The seawater pump control system collects data from sensors on the seawater pump, seawater filter, seawater heat exchanger, and components to be cooled, and implements state control of the seawater pump based on the data. The seawater cooling device according to claim 1 is characterized in that: The seawater pump comprises a main seawater pump and a standby seawater pump; Wherein, each seawater pump is provided with a start-stop controller, and the start-stop controller realizes the start-stop control of the seawater pump based on the seawater pump control system; When the seawater pump control system is turned on, the start-stop controller of the main seawater pump is in the start state by default, and the start-stop controller of the standby seawater pump is in the stop state by default. The seawater cooling device according to claim 2 is characterized in that: A pressure sensor is also provided on the water delivery end of the seawater pump, and the pressure sensor is configured to detect the pressure of the water delivery end of the seawater pump and transmit the detection result to the seawater pump control system; When the detection result is lower than the protection set value, other seawater pumps that are in the shut-down state are started. The seawater cooling device according to claim 3 is characterized in that: The seawater inlet and outlet of the seawater heat exchanger are respectively provided with a temperature sensor and a flow meter, and the temperature sensor and the flow meter are configured to realize statistics of the heat exchange amount of the seawater heat exchanger per unit time, and transmit the statistical results to the seawater pump control system; The seawater pump control system simultaneously collects the heat dissipation of the cooled component per unit time, and realizes the start and stop control of the seawater pump by comparing the heat exchange amount and the heat dissipation. The seawater cooling device according to claim 4 is characterized in that: The seawater heat exchanger is a non-contact plate heat exchanger. According to a seawater cooling device according to any one of claims 2 to 5, the seawater pumps include three main seawater pumps and one standby seawater pump; and at each moment, three seawater pumps are in operation. The seawater cooling device according to claim 1 is characterized in that: The device also includes a leak detection tank, the water inlet of which is respectively connected to the water outlet of the seawater filter and the water outlet of the seawater heat exchanger through drainage pipes, and a liquid level sensor is also arranged inside the leak detection tank. The seawater cooling device according to claim 7 is characterized in that: The liquid level sensor is used to detect the liquid level inside the leak detection tank when the seawater pump is shut down; when the liquid level inside the leak detection tank changes by more than a set value in a short period of time, a seawater leakage warning is issued through the seawater pump control system. The seawater cooling device according to claim 7 is characterized in that: The leak detection tank is integrally formed with the drainage pipe, and is arranged at the end of the drainage pipe, and the leak detection tank is above the liquid level of the seawater pump, the seawater filter, and the seawater heat exchanger. The seawater cooling device according to claim 9 is characterized in that: The drainage pipeline includes at least one vertically arranged pipeline on one side close to the leak detection tank, so that the leak detection tank is above the liquid level of the seawater pump, the seawater filter and the seawater heat exchanger. A seawater pump control method, characterized in that: The method is implemented by using the seawater cooling device in any one of claims 1 to 10; and the method comprises the following steps: Step 1, collecting the current heat dissipation of the device to be cooled in the seawater cooling device, and estimating the current heat exchange capacity of the seawater pump based on the current heat dissipation; Step 2, calculating the number of the seawater pumps that should be activated currently based on the rated heat exchange capacity and the current heat exchange capacity of each of the seawater pumps; Step 3: start and stop the seawater pump based on the quantity. According to a seawater pump control method as claimed in claim 11, it is characterized in that: The seawater pump control system also adopts a power supply switching method to realize power supply to the seawater pump. According to a seawater pump control method as claimed in claim 12, it is characterized in that: The seawater pump control system uses a dual power supply switching rear busbar method to power the seawater pump. According to a seawater pump control method as claimed in claim 12, it is characterized in that: The control system collects the operating time of the seawater pump. If the current operating time of the seawater pump exceeds a set threshold, it determines whether there is an idle seawater pump in the seawater cooling device. If so, the current seawater pump is shut down and the idle seawater pump is started. A seawater pump control method according to any one of claims 11 to 14, characterized in that: If the seawater pump has an overheat alarm, a soft starter alarm, or a power supply alarm, the control system switches the operating state of the seawater pump.