Offshore converter station valve hall air conditioning system and design method thereof

Abstract

The invention discloses an offshore converter station valve hall air conditioning system and a design method thereof. The design method comprises the steps that an enthalpy-humidity diagram is drawn, and the summer indoor design state point parameter range is determined by combining the enthalpy-humidity diagram; the air volume required by positive pressure is calculated through a gap method, the maximum value between the air volume required by the positive pressure and the fresh air volume calculated by not smaller than 0.5 times / h is measured, and the fresh air volume is determined; determining summer air conditioner parameters according to the determined fresh air volume and the summer indoor design state point parameter range; determining winter air conditioner parameters according to the determined fresh air volume and summer air conditioner parameters; and according to the determined summer air conditioner parameters and winter air conditioner parameters, design parameters of the valve hall air conditioner system are obtained. According to the design method, the temperature and humidity of the internal environment of the converter station valve hall can be reasonably controlled, the valve hall can maintain micro-positive pressure, and key technical support can be provided for reasonable model selection and configuration of an air conditioning system of the offshore converter station valve hall.

Description

Technical Field

[0001] The present application relates to the field of offshore wind power technology, and in particular to an offshore converter station valve hall air conditioning system and a design method thereof. Background Art

[0002] As offshore wind power in my country becomes increasingly saturated, offshore wind power has gradually become the mainstream of the industry. With the increasing size of offshore wind turbines, the expansion of installed capacity and offshore distance, large-scale offshore wind power output technology based on flexible DC transmission technology will become a hot topic in offshore wind power development and research. Offshore converter stations are key components of offshore wind farms and the hub of offshore wind power access projects. Their safe and reliable operation is directly related to the stable operation of the entire power grid. Valve hall air conditioning systems are crucial auxiliary equipment for the safe and stable operation of offshore converter stations.

[0003] The converter valves within the valve hall of a converter station are core electrical equipment within the flexible direct current converter station of an offshore wind turbine platform. The converter valve tower generates significant heat. Although cooling water removes most of the heat, the valves still dissipate heat to the valve hall through radiation and convection. Therefore, to dissipate the heat dissipated by the converter valves into the air in the valve hall, the valve hall temperature must be controlled within a certain range to prevent overheating in certain areas, which could shorten the equipment's service life or even cause damage. Furthermore, to prevent flashover during valve operation, the valve hall air conditioning system must maintain relative humidity within the required range. Furthermore, the valve hall air conditioning system must supply a sufficient amount of fresh air to maintain a slight positive pressure within the valve hall to prevent contaminants such as outdoor salt spray and dust from penetrating through doors, openings, and gaps in the enclosure structure. Therefore, it is essential to maintain appropriate temperature and humidity control and a slight positive pressure within the valve hall of the converter station. To achieve these goals, an efficient and reliable valve hall air conditioning system is essential for the offshore converter station valve hall.

[0004] The existing valve hall air-conditioning system of offshore converter stations is not efficient and reliable. Therefore, providing a design method for the valve hall air-conditioning system of offshore converter stations to provide important technical support for the reasonable selection and configuration of the valve hall air-conditioning system is a key technical problem that needs to be solved urgently. Summary of the Invention

[0005] The purpose of this application is to provide an offshore converter station valve hall air-conditioning system and a design method thereof, to provide key technical support for the reasonable selection and configuration of the valve hall air-conditioning system, and to configure an efficient and reliable valve hall air-conditioning system for the offshore converter station valve hall.

[0006] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0007] On the one hand, an embodiment of the present application provides a method for designing a valve hall air conditioning system for an offshore converter station, comprising:

[0008] Drawing a psychrometric diagram, and determining the parameter range of the indoor design state point in summer based on the psychrometric diagram;

[0009] Calculate the air volume required for positive pressure using the gap method , measure the air volume required according to the positive pressure and not less than The maximum value among the calculated fresh air volumes is used to determine the fresh air volume. ;

[0010] According to the determined fresh air volume and the summer indoor design state point parameter range, determining summer air conditioning parameters;

[0011] According to the determined air supply volume of air conditioner and the summer air conditioning parameters, determining the winter air conditioning parameters;

[0012] According to the determined summer air-conditioning parameters and the winter air-conditioning parameters, design parameters of the valve hall air-conditioning system are obtained.

[0013] In some embodiments, determining the summer indoor design state point parameter range includes determining the temperature of the valve hall indoor design state point , relative humidity and moisture content ,in,

[0014] The temperature satisfy: ;

[0015] The relative humidity satisfy: ;

[0016] The moisture content satisfy: , It is the humidity content at the outdoor design state point.

[0017] In some embodiments, determining the summer indoor design state point parameter range further includes determining the selected air supply temperature difference according to the selected air supply temperature difference. , narrow the summer interior design state point parameter range, and obtain the final summer interior design state point parameter range of the valve hall.

[0018] In some embodiments, the gap method is calculated by the following formula:

[0019] ,

[0020] Where, The air volume required for the positive pressure of the slit method; It is a safety factor determined based on the air tightness of the enclosure structure, with a value range of 1.1~1.2; It is the air leakage volume per unit length of the gap in the enclosure structure when the room is at a certain pressure difference; is the gap length of the enclosure structure.

[0021] In some embodiments, determining the summer air conditioning parameters includes determining the indoor design state point, the outdoor air design state point, the valve hall equipment heat value, and the heat value of the valve hall equipment. and the selected supply air temperature difference , determine the air supply volume of the air conditioner , air conditioning reheat load and air conditioning cooling capacity ,in,

[0022] Air conditioning air supply volume , which is calculated by the following formula: ,

[0023] Where, Provides heat for valve hall equipment; It is the humidity content of the indoor design state point in summer; is the air density at the air supply point;

[0024] The air conditioning reheat load , which is calculated by the following formula:

[0025] ,

[0026] Where, is the air density at the air supply point; is the specific enthalpy at the air supply point; is the specific enthalpy of the dew point;

[0027] The air conditioning cooling capacity , which is calculated by the following formula: ,

[0028] Where, is the fresh air volume; is the specific enthalpy of the interior design point; is the specific enthalpy of the outdoor design point.

[0029] In some embodiments, determining the winter air conditioning parameters includes determining the air supply volume of the air conditioner according to the determined and the selected supply air temperature difference , so that the temperature of the indoor design state point in winter Greater than or equal to the temperature of the indoor design state point in summer , and determine the minimum humidification condition;

[0030] The minimum humidification condition meets the following requirements:

[0031] ;

[0032] ;

[0033] ;

[0034] Where, The relative humidity at the indoor design state point in summer; The temperature of the air supply point in winter.

[0035] In some embodiments, the minimum humidification amount is determined based on the indoor condition of minimum humidity and no humidity load. and air conditioning humidification capacity ;

[0036] The air conditioning humidification capacity , which is calculated by the following formula:

[0037] ,

[0038] in, ,

[0039] Where, The temperature of the air supply point in winter; is the fresh air volume; It is the humidity content of the indoor design state point in winter; The humidity content at the outdoor design state point in winter; is the saturated water vapor pressure.

[0040] In some embodiments, determining the winter air conditioning parameters includes preheating the fresh air according to the working condition that the water pipe of the surface cooler is frozen and cracked due to the outdoor cold air at the fresh air inlet, and determining the preheating temperature of the fresh air , which is calculated by the following formula:

[0041] ,

[0042] Where, The air density at the air supply point in winter; is the fresh air volume; Design the temperature of the outdoor state point for winter;

[0043] And according to the valve hall indoor temperature is not less than 10℃ when the valve hall is shut down and the heat load of air conditioning in winter Working conditions, determine the air conditioning heating capacity when the valve hall is out of service , which is calculated by the following formula:

[0044] ，

[0045] Where, It is the air density when the indoor temperature of the valve hall is 10℃.

[0046] In some embodiments, the design parameters of the valve hall air conditioning system include the air supply volume , air conditioning cooling capacity , air conditioning reheat load , air conditioning humidification capacity and air conditioning heating capacity ,in,

[0047] The air conditioning heating capacity ,

[0048] Where, Preheat the fresh air for air conditioning; The air conditioning heating amount when the valve hall is out of service.

[0049] On the other hand, an embodiment of the present application provides an offshore converter station valve hall air conditioning system, which is selected and configured using design parameters obtained by the offshore converter station valve hall air conditioning system design method provided in any of the aforementioned embodiments.

[0050] This application has the following beneficial effects:

[0051] The embodiment of the present application provides a method for designing an offshore converter station valve hall air conditioning system. The method determines the range of indoor design state point parameters in summer by using a psychrometric diagram in combination with the psychrometric diagram, and uses the gap method to determine the fresh air volume. Furthermore, the summer air conditioning parameters are determined based on the determined fresh air volume and the range of indoor design state point parameters in summer. At the same time, the winter air conditioning parameters are determined based on the determined fresh air volume and summer air conditioning parameters, and the final valve hall air conditioning system design parameters can be obtained based on the determined summer air conditioning parameters and winter air conditioning parameters. By adopting the design method of the present application, the temperature and humidity of the internal environment of the offshore converter station valve body can be controlled within a reasonable range, and a certain micro-positive pressure can be maintained. This method provides key technical support for the reasonable selection and configuration of the valve hall air conditioning system of the offshore wind power converter station, and can configure an efficient and reliable valve hall air conditioning system for the offshore converter station valve hall. At the same time, this design method greatly improves the efficiency of standardized design and batch design of the valve hall air conditioning system of the offshore wind power converter station. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is a flow chart of a design method for an offshore converter station valve hall air conditioning system in an embodiment of the present application;

[0053] Figure 2 This is a schematic diagram of the indoor state point range in the embodiment of this application;

[0054] Figure 3 Schematic diagram of the indoor state point range after the supply air temperature difference is selected in the embodiment of the present application;

[0055] Figure 4 This is a schematic diagram of the summer air treatment process in the embodiment of the present application;

[0056] Figure 5 This is a schematic diagram of the winter air treatment process in an embodiment of the present application. DETAILED DESCRIPTION

[0057] The following describes the implementation of the present application through specific embodiments. People familiar with this technology can easily understand other advantages and effects of the present application from the contents disclosed in this specification.

[0058] It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of this application will be clearly and completely described below in combination with the drawings in the embodiments of this application. Obviously, the described embodiments are only embodiments of a part of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of this application.

[0059] It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. In addition, the terms "comprises", "includes" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a..." does not exclude the presence of other identical elements in the process, article or device comprising the element; for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0060] In the embodiments of this application, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be interpreted as being preferred or advantageous over other embodiments or designs; rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0061] The offshore converter station is the core hub connecting the offshore wind farm and the onshore power grid. It undertakes the key functions of power collection, voltage conversion and power control. Its operational safety and reliability directly affect the stability of the entire transmission system.

[0062] The valve hall of a converter station, a core area, houses key electrical equipment such as the converter valve tower, valve control equipment, and cooling systems. The converter valve is the core electrical equipment within the flexible direct current converter station of an offshore wind turbine platform. The converter valve tower generates significant heat. Although cooling water removes most of the heat, the converter valve still dissipates heat to the valve hall through radiation and convection. Therefore, to remove the heat dissipated by the converter valve into the air in the valve hall and keep the valve hall temperature within a certain range, it is crucial to prevent overheating in certain areas, shortening equipment life, or even causing burnout. Furthermore, to prevent flashover during valve operation, the valve hall air conditioning system must maintain relative humidity within a specified range. Furthermore, the valve hall air conditioning system must supply a sufficient amount of fresh air to maintain a slight positive pressure within the valve hall to prevent contaminants such as outdoor salt spray and dust from penetrating through doors, openings, and gaps in the surrounding structure. Therefore, the valve hall environment in offshore converter stations requires proper temperature and humidity control and a slight positive pressure.

[0063] To achieve the above objectives, on the one hand, an embodiment of the present application provides a method for designing a valve hall air conditioning system for an offshore converter station. Figure 1 This is a flow chart of the design method for the valve hall air conditioning system of the offshore converter station in the embodiment of the present application. Figure 1 As shown, in some embodiments, the design method specifically includes the following steps:

[0064] S100. Draw a psychrometric diagram, and determine the parameter range of the indoor design state point in summer based on the psychrometric diagram.

[0065] According to the following formula:

[0066] (1)

[0067] Where, is the relative humidity; is the water vapor partial pressure, in Pa; is the saturated water vapor partial pressure, in Pa.

[0068] (2)

[0069] (3)

[0070] Where, is the moisture content, unit is g / kg.

[0071] (4)

[0072] in, ; ; ; ; ; ; .

[0073] (5)

[0074] in, ; ; ; ; ; .

[0075] (6)

[0076] Where, is the specific enthalpy, and its unit is kJ / kg.

[0077] (7)

[0078] Where, is the air density in units of .

[0079] (8)

[0080] In this step, for the large space valve hall with high heat generation, there is no wet load in the valve hall, and the air conditioning adopts the full air conditioning system for cooling.

[0081] First, determine the design temperature of the valve hall's indoor air design state point in summer. (℃), relative humidity (%), moisture content (g / kg) and specific enthalpy (kJ / kg), and the temperature of the outdoor air design state point , relative humidity , moisture content and specific enthalpy , and in order to prevent condensation in the valve hall, the fresh air needs to be dehumidified, then:

[0082] (9)

[0083] Furthermore, in actual applications, the valve hall air conditioner's condensing effect is completely lost when the dew point of the air supply falls below the chilled water temperature in the surface cooler. Operating experience shows that when the dew point of the valve hall air conditioner's inlet air differs by 2°C from the chilled water temperature passing through the surface cooler, the valve hall air conditioner's dehumidification performance deteriorates significantly. The surface cooler's chilled water return temperature is designed to be 12°C. Therefore, to ensure effective dehumidification, the air conditioner's supply air dew point should be no less than 16°C, meaning the maximum dew point temperature is 16°C.

[0084] According to the above, the dew point air parameter of the air conditioner is the temperature , relative humidity (The relative humidity of the dew point of the air conditioner can be 90%, that is ), moisture content and specific enthalpy , then:

[0085] (10)

[0086] (11)

[0087] (12)

[0088] At the same time, according to the "Flexible DC Transmission Converter Station Design Standard" GB∕T 51381-2019 and the "Offshore Flexible DC Converter Station Design Code" NBT11403-2023, the valve hall temperature and humidity are 、 For control, there are:

[0089] (13)

[0090] (14)

[0091] Due to the relative humidity requirements of the valve hall In order to avoid the local relative humidity in the valve hall being greater than 60%, the relative humidity of the air-conditioning supply air is designed to be no greater than 60%, so:

[0092] (15)

[0093] (16)

[0094] Where, is the relative humidity at the air supply point; It is the humidity content at the air supply point, in g / kg.

[0095] Then from the above formulas (1)-(16), we can get:

[0096] (17)

[0097] (18)

[0098] (19)

[0099] According to the above equations (1)-(6), the enthalpy-humidity diagram is drawn and combined with equations (17)-(19), the following can be obtained: Figure 2 Psychrometric diagram shown. Figure 2 This is a schematic diagram of the indoor state point range in the embodiment of this application. Figure 2 The shaded area in the figure shows the parameter range of the interior design state point. It can be understood that Figure 2 The shaded area in the figure can be the feasible range of the interior design status points of the offshore valve hall.

[0100] For example, determining the summer indoor design state point parameter range may also include determining the supply air temperature difference according to the limit. , further narrow the parameter range of the interior design state points, and obtain the final parameter range of the valve hall's summer interior design state points. Figure 3 This is a schematic diagram of the indoor state point range after the selected air supply temperature difference in the embodiment of this application. The final valve hall summer indoor design state point parameter range is as follows: Figure 3 The shaded portion is shown.

[0101] According to Article 8.4.9 of the "Design Code for Heating, Ventilation and Air Conditioning of Industrial Buildings" (GB50019-2015), the air supply temperature difference of air conditioners shall be selected as shown in Table 1 below.

[0102]

[0103] According to Article 3.1.1 of the Design Method for HVAC Systems on Offshore Platforms (Q / HS3008-2016), the outdoor air design parameters are selected according to Table 2 below.

[0104]

[0105] S200, calculate the required air volume for positive pressure using the gap method , measure the air volume required according to positive pressure and not less than The maximum value among the calculated fresh air volumes is used to determine the fresh air volume. .

[0106] In the embodiment of this application, in order to prevent outdoor pollutants such as salt spray and dust from penetrating into the valve hall through doors, holes and gaps in the enclosure structure, the air conditioning system needs to supply a certain amount of fresh air to maintain a certain slight positive pressure in the valve hall. The air volume required for positive pressure is calculated using the gap method. The gap method takes into account both the air tightness of the room enclosure and the air volume required to maintain a certain positive pressure value indoors. .

[0107] The gap method is calculated by the following formula:

[0108] (20)

[0109] Where, The air volume required for the positive pressure of the gap method, unit is ;

[0110] It is a safety factor determined according to the air tightness of the enclosure structure, and the value range can be 1.1~1.2;

[0111] When the room is under a certain pressure difference, the air leakage volume per unit length of the enclosing structure is expressed in units of ;

[0112] is the gap length of the enclosure structure, in m.

[0113] According to the "Cleanroom Design Code" GB50073-2013, the amount of air leakage per unit length of gaps is shown in Table 3.

[0114] Since the rooms in the offshore converter station are all windowless rooms and the doors are all sealed doors, the air leakage per unit length of the gap can be taken according to the value of the sealed door in Table 3.

[0115]

[0116] In the embodiment of this application, considering the requirements of the "Flexible DC Transmission Converter Station Design Standard" GB∕T 51381-2019 The ventilation volume after the accident is required, and the air conditioning unit is used to send fresh air as the post-disaster ventilation system, using a mechanical air intake and natural exhaust system, reducing the holes in the valve hall, and designing the fresh air volume to be no less than Therefore, the fresh air volume is calculated based on the required positive pressure and not less than The maximum value between the calculated fresh air volumes is used to determine the fresh air volume. .

[0117] S300, according to the determined fresh air volume And the summer indoor design state point parameter range, determine the summer air-conditioning parameters.

[0118] According to the determined indoor design state points (including temperature , relative humidity ), outdoor air design state point (including temperature , relative humidity ), valve hall equipment heat Q and the selected supply air temperature difference , determine the air supply volume of the air conditioner , air conditioning reheat load and air conditioning cooling capacity , then:

[0119] (twenty one)

[0120] According to the above formulas (6)-(8), the air supply volume of the air conditioner can be obtained :

[0121] (twenty two)

[0122] Where, The heat generated by the valve hall equipment, in kW; The humidity content at the indoor design state point in summer, in g / kg; is the air density at the air supply point, in units of .

[0123] Available air conditioning reheat load (twenty three)

[0124] Where, is the air density at the air supply point, in units of ; is the specific enthalpy of the air supply point; is the specific enthalpy of the dew point.

[0125] Available air conditioning cooling capacity (twenty four)

[0126] Where, is the fresh air volume, in units of ; is the specific enthalpy of the interior design point; is the specific enthalpy of the outdoor design point.

[0127] S400, according to the determined air supply volume of the air conditioner and summer air-conditioning parameters to determine winter air-conditioning parameters.

[0128] In actual application scenarios, since the heat generated by the valve hall equipment increases as the indoor temperature decreases, and the heat dissipation of the enclosure structure in winter is considered as a design margin, if the indoor design temperature is lowered, the heat generated by the valve hall equipment will increase, and the selected air supply temperature difference It has been determined by the summer working conditions. According to the above formula (22), the air supply volume of the air conditioner will increase, but the air supply volume of the air conditioner Determined by summer operating conditions.

[0129] Therefore, the temperature of the indoor design state point in winter can be Greater than or equal to the temperature of the indoor design state point in summer , and determine the minimum humidification condition, then:

[0130] (25)

[0131] (26)

[0132] (27)

[0133] Where, Relative humidity at the design state point for indoor use in winter; The temperature of the air supply point in winter.

[0134] Since there is no humidity load indoors, according to equations (1) and (2), the relative humidity is constant, and the lower the temperature, the lower the moisture content. Therefore, the humidification amount of fresh air at this state point is the minimum. The minimum humidification amount is determined by and air conditioning humidification capacity 。

[0135] Then the above equations (1)-(4), (25), and (26) can be used to obtain the minimum humidification amount. :

[0136] (28)

[0137] Where, is the saturated water vapor pressure.

[0138] Then, according to the known winter outdoor air state parameters (including temperature , relative humidity , moisture content and specific enthalpy ） , you can get the air conditioning humidification capacity :

[0139] (29)

[0140] Where, The temperature of the air supply point in winter; is the fresh air volume, in units of ; The humidity content at the indoor design state point in winter, in g / kg; It is the moisture content at the outdoor design state point in winter, in g / kg.

[0141] At the same time, in order to prevent the fresh air inlet from freezing and cracking the surface cooler water pipes due to the outdoor cold air, the fresh air needs to be preheated and can be preheated to 5°C. Therefore, according to the working condition that the fresh air inlet may cause the surface cooler water pipes to freeze and crack due to the outdoor cold air, the fresh air can be preheated and the air conditioning fresh air preheating temperature can be determined. , then:

[0142] (30)

[0143] Where, is the air density at the air supply point in winter, in units of ; is the fresh air volume, in units of ; The temperature of the outdoor design state point in winter.

[0144] In actual application scenarios, when the valve hall is shut down, it is necessary to ensure that the indoor temperature of the valve hall is not lower than 10°C. Therefore, the indoor temperature of the valve hall is not lower than 10°C when the valve hall is shut down and the heat load of the air conditioner in winter can be used as the reference. Working conditions, determine the air conditioning heating capacity when the valve hall is out of service , then:

[0145] (31)

[0146] Where, is the fresh air volume, in units of ; Design point temperature for winter outdoor areas; is the air density when the indoor temperature of the valve hall is 10℃, in units of .

[0147] S500: Obtain design parameters of the valve hall air conditioning system according to the determined summer air conditioning parameters and winter air conditioning parameters.

[0148] According to the fresh air volume determined above , summer air conditioning parameters and winter air conditioning parameters, the final valve hall air conditioning system design parameters can be obtained. The valve hall air conditioning system design parameters can include air conditioning air volume ( ), air conditioning cooling capacity (kW), air conditioning reheat load (kW), air conditioning humidification capacity (kg / h) and air conditioning heating capacity (kW), where

[0149] ;

[0150] ;

[0151] ;

[0152] ;

[0153] ;

[0154] Where, Preheat the fresh air for air conditioning; The air conditioning heating amount when the valve hall is out of service.

[0155] The design method provided in the embodiment of the present application uses a psychrometric diagram and combines it to determine the parameter range of the summer indoor design state point, and uses the gap method to determine the fresh air volume. Furthermore, the summer air conditioning parameters are determined based on the determined fresh air volume and the summer indoor design state point parameter range. At the same time, the winter air conditioning parameters are determined based on the determined fresh air volume and summer air conditioning parameters, and the final valve hall air conditioning system design parameters are obtained based on the determined summer air conditioning parameters and winter air conditioning parameters. The design method of the present application can control the temperature and humidity within the valve body of the offshore converter station within a reasonable range, while also maintaining a certain micro-positive pressure, providing key technical support for the reasonable selection and configuration of the valve hall air conditioning system of the offshore converter station.

[0156] At the same time, the design method provided in the embodiment of the present application greatly improves the standardized design and batch design efficiency of the valve hall air-conditioning system of the offshore wind power converter station, providing key technical support for the rapid development of the industry.

[0157] In another aspect, an embodiment of the present application provides an offshore converter station valve hall air conditioning system, which is selected and configured using design parameters obtained by the offshore converter station valve hall air conditioning system design method provided in any of the aforementioned embodiments.

[0158] The offshore converter station valve hall air-conditioning system provided in the embodiments of the present application can effectively eliminate the heat emitted by equipment such as converter valves to ensure that the valve hall temperature is moderate and within a safe operating range; it can also control the humidity within a reasonable range to prevent condensation and flashover; at the same time, the fresh air system can maintain a certain slight positive pressure in the valve hall, effectively preventing outdoor pollutants such as salt spray and dust from penetrating into the valve hall through doors, holes, and gaps in the enclosure structure.

[0159] The valve hall air conditioning system of the offshore converter station is very suitable for harsh offshore environments such as high humidity, high salt fog and strong corrosion, and has the ability to operate efficiently, reliably and stably for a long time.

[0160] Example 1

[0161] This embodiment takes an offshore wind power converter station in the Yellow Sea as an example. The known heating value of valve hall equipment is shown in Table 4 below.

[0162]

[0163] In this embodiment, the selected supply air temperature difference is 7° C., and the design indoor state point is selected as a temperature of 35° C. and a relative humidity of 40%.

[0164] According to Table 4, the heat generated by the valve hall equipment is 540kW, the heat load during winter shutdown is 250kW, and the room volume is 52000 , the fresh air volume is based on the number of ventilation times Calculated as 26000 .

[0165] Figure 4 This is a schematic diagram of the summer air treatment process in the embodiment of the present application. According to the design method provided in the embodiment of the present application, the summer air treatment process is as follows Figure 4 shown. Figure 4 The parameters of each state point in summer are shown in Table 5 below.

[0166]

[0167] According to the summer air treatment process, the design parameters of the summer air conditioning system can be obtained as follows:

[0168] Air supply volume ;

[0169] Fresh air volume ;

[0170] Total cooling capacity of the unit ;

[0171] Indoor cooling load ;

[0172] Fresh air load ;

[0173] Reheat cooling load .

[0174] Figure 5 This is a schematic diagram of the winter air treatment process in the embodiment of this application. According to the design method provided in the embodiment of this application, the winter air treatment process is as follows Figure 5 shown. Figure 5The parameters of each state point in winter are shown in Table 6 below.

[0175]

[0176] According to the winter air treatment process, the air conditioning humidification capacity can be obtained ,

[0177] .

[0178] In order to prevent the fresh air inlet from freezing and cracking the surface cooler water pipe due to the outdoor cold air, the fresh air is preheated to 5℃, which can obtain the fresh air preheating temperature of the air conditioner. ,

[0179] .

[0180] According to the indoor temperature of the valve hall when the valve hall is shut down and the heat load of the air conditioner in winter, If the working condition is correct, the air conditioning heating capacity when the valve hall is shut down can be obtained. ,

[0181] .

[0182] According to the aforementioned summer air treatment process and winter air treatment process, the design parameters of the valve hall air conditioning system can be obtained as follows:

[0183] Air conditioning air volume ;

[0184] Fresh air volume ;

[0185] Air conditioning cooling capacity ;

[0186] Air conditioning heating capacity ;

[0187] Air conditioning humidification capacity .

[0188] The above description is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any variation, modification or equivalent substitution made by those skilled in the art without departing from the technical concept of the present application, and all embodiments obtained, shall fall within the scope of protection of the claims of the present application.

Claims

1. A design method for an offshore converter station valve hall air conditioning system, characterized in that: include: Drawing a psychrometric diagram, and determining the parameter range of the indoor design state point in summer based on the psychrometric diagram; Calculate the air volume required for positive pressure using the gap method , measure the air volume required according to the positive pressure and not less than The maximum value among the calculated fresh air volumes is used to determine the fresh air volume. ; According to the determined fresh air volume and the summer indoor design state point parameter range, determining summer air conditioning parameters; According to the determined air supply volume of air conditioner and the summer air conditioning parameters, determining the winter air conditioning parameters; According to the determined summer air-conditioning parameters and the winter air-conditioning parameters, design parameters of the valve hall air-conditioning system are obtained.

2. The design method of the valve hall air conditioning system of the offshore converter station according to claim 1 is characterized in that: Determine the parameter range of the indoor design state point in summer, including determining the temperature of the indoor design state point of the valve hall , relative humidity and moisture content ,in, The temperature satisfy: ; The relative humidity satisfy: ; The moisture content satisfy: , It is the humidity content at the outdoor design state point.

3. The design method of the valve hall air conditioning system of the offshore converter station according to claim 1 is characterized in that: Determining the summer indoor design state point parameter range also includes the selected air supply temperature difference , narrow the summer interior design state point parameter range, and obtain the final summer interior design state point parameter range of the valve hall.

4. The design method of the valve hall air conditioning system of the offshore converter station according to claim 1 is characterized in that: The gap method is calculated by the following formula: ， Where, The air volume required for the positive pressure of the slit method; It is a safety factor determined based on the air tightness of the enclosure structure, with a value range of 1.1~1.2; It is the air leakage volume per unit length of the gap in the enclosure structure when the room is at a certain pressure difference; is the gap length of the enclosure structure.

5. The design method of the valve hall air conditioning system of the offshore converter station according to claim 1 is characterized in that: Determine the summer air conditioning parameters, including the indoor design state point, outdoor air design state point, valve hall equipment heat and the selected supply air temperature difference , determine the air supply volume of the air conditioner , air conditioning reheat load and air conditioning cooling capacity ,in, Air conditioning air supply volume , which is calculated by the following formula: ， Where, Provides heat for valve hall equipment; It is the humidity content of the indoor design state point in summer; is the air density at the air supply point; The air conditioning reheat load , which is calculated by the following formula: ， Where, is the air density at the air supply point; is the specific enthalpy at the air supply point; is the specific enthalpy of the dew point; The air conditioning cooling capacity , which is calculated by the following formula: ， Where, is the fresh air volume; is the specific enthalpy of the interior design point; is the specific enthalpy of the outdoor design point.

6. The design method of the valve hall air conditioning system of the offshore converter station according to claim 1 is characterized in that: Determine the winter air conditioning parameters, including the air supply volume of the air conditioning determined and the selected supply air temperature difference , so that the temperature of the indoor design state point in winter Greater than or equal to the temperature of the indoor design state point in summer , and determine the minimum humidification condition; The minimum humidification condition meets the following requirements: ； ； ； Where, The relative humidity at the indoor design state point in summer; The temperature of the air supply point in winter.

7. The offshore converter station valve hall air conditioning system design method according to claim 6, characterized in that: Determine the minimum humidification capacity based on the indoor working conditions of minimum humidity and no moisture load. and air conditioning humidification capacity ; The air conditioning humidification capacity , which is calculated by the following formula: ， in, , Where, The temperature of the air supply point in winter; is the fresh air volume; It is the humidity content of the indoor design state point in winter; The humidity content at the outdoor design state point in winter; is the saturated water vapor pressure.

8. The design method of the valve hall air conditioning system of an offshore converter station according to claim 1, characterized in that: Determine the winter air conditioning parameters, including preheating the fresh air according to the working condition that the surface cooler water pipe is frozen and cracked due to the outdoor cold air at the fresh air inlet, and determine the preheating amount of the fresh air , which is calculated by the following formula: ， Where, The air density at the air supply point in winter; is the fresh air volume; Design the temperature of the outdoor state point for winter; And according to the valve hall indoor temperature is not less than 10℃ when the valve hall is shut down and the heat load of air conditioning in winter Working conditions, determine the air conditioning heating capacity when the valve hall is out of service , which is calculated by the following formula: ， Where, It is the air density when the indoor temperature of the valve hall is 10℃.

9. The offshore converter station valve hall air conditioning system design method according to claim 1, characterized in that: The design parameters of the valve hall air conditioning system include the air supply volume , air conditioning cooling capacity , air conditioning reheat load , air conditioning humidification capacity and air conditioning heating capacity ,in, The air conditioning heating capacity , Where, Preheat the fresh air for air conditioning; The air conditioning heating amount when the valve hall is out of service.

10. An offshore converter station valve hall air conditioning system, characterized in that: The design parameters obtained by the offshore converter station valve hall air-conditioning system design method according to any one of claims 1 to 9 are used for model selection and configuration.

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