A method for regulating the load of a compressor in an air-conditioning box for a uranium enrichment auxiliary process

Abstract

The present invention belongs to the field of automatic control technology and specifically discloses a method for regulating the compressor load of an air-conditioning box in a uranium enrichment auxiliary process. The method comprises the following steps: Step 1: calculating the deviation value T between the actual ambient dew point temperature of the cascade hall and the dew point temperature control target value; Step 2: determining the return air dew point temperature set value T3 of the air-conditioning box based on the deviation between the actual ambient dew point temperature of the cascade hall and the dew point temperature control target value; Step 3: automatically obtaining the return air dry-bulb temperature T4 based on the return air dew point temperature set value T3 and writing it into the air-conditioning box PLC program as the set value; Step 4: the air-conditioning field PLC module automatically converts the set return air dry-bulb temperature T4 to obtain the return air dew point temperature set value T3, thereby automatically regulating the compressor load of the air-conditioning unit. The method of the present invention realizes effective regulation and control of the air-conditioning box equipment, ensures the temperature and humidity control accuracy of the cascade hall, and achieves energy-saving operation of the air-conditioning equipment of the auxiliary process system.

Description

Technical Field

[0001] The invention belongs to the technical field of automatic control, and in particular relates to a method for regulating the load of a compressor in an air-conditioning box of a uranium enrichment auxiliary process. Background Art

[0002] The air conditioning system for the cascade hall of the CNNC Shaanxi Uranium Phase II project utilizes direct expansion (DE) air conditioners, each with its own cooling and heating source. Two air conditioning rooms are located on the north and south sides of the hall, each housing four supply and return air units, totaling eight. These units control the temperature and humidity of the cascade hall. The DE units primarily consist of two main components: an air handling unit (AHU) and an air-cooled heat pump rooftop unit (outdoor unit), directly connected by copper tubing. The evaporator is located within the AHU, with refrigerant flowing through the evaporator coil. The air outside the coil is cooled and dehumidified (or heated) by the evaporator before being returned to the indoor space after a series of treatments. The AHU unit utilizes a PLC controller to control the compressor, dampers, and blower. Currently, the CNNC Shaanxi Uranium auxiliary process system implements remote monitoring of the AHU PLCs through a DCS system. A higher-level intelligent control platform has been established, utilizing advanced control technology to automate the AHU operation.

[0003] A key performance indicator for the auxiliary control system in the uranium enrichment process is maintaining constant temperature and humidity in the uranium enrichment cascade hall. Excessively high dry-bulb temperatures in the cascade hall can cause condensation and frost on core production equipment; excessively low dry-bulb temperatures can lead to quality fluctuations in the primary process product. Therefore, under stringent process specifications, ensuring that the hall's dry-bulb temperature fluctuates within the target range of + / -1°C and that the dew point does not exceed a set value has become a key technical challenge in the uranium enrichment auxiliary process.

[0004] Due to the inherent limitations of the uranium enrichment auxiliary process air conditioning system, operators manually set the return air dry-bulb temperature setpoint. The on-site PLC then compares the dew-point setpoint obtained by looking up the current ambient humidity and dry-bulb temperature setpoints in a fixed, queryable table. This table then compares the dew-point setpoint with the actual return air dew-point temperature to automatically adjust the air conditioning compressor load. This adjustment method is confusing, computationally complex, and extremely inconvenient, requiring a large amount of manual work. It also fails to accurately match cooling capacity to environmental requirements in real time, resulting in energy waste. Therefore, under the existing load control strategy, the air conditioning unit is unable to effectively adjust the air conditioning compressor load based on changes in the ambient temperature and humidity in the cascade hall. This creates a high risk of exceeding the ambient dew-point temperature limit in the cascade hall, and the overall operating energy consumption of the air conditioning unit is high. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for regulating the load of a compressor in an air-conditioning box for an auxiliary process of uranium enrichment, which takes the ambient temperature and humidity of a cascade hall as the main basis for regulating the load of the air-conditioning box compressor, thereby achieving effective regulation and control of the air-conditioning box equipment, while ensuring the control accuracy of the temperature and humidity in the cascade hall and realizing energy-saving operation of the air-conditioning equipment in the auxiliary process system.

[0006] The technical solution for achieving the purpose of the present invention is as follows:

[0007] A method for adjusting the load of a compressor in an air-conditioning box of a uranium enrichment auxiliary process, the method specifically comprising the following steps:

[0008] Step 1: Calculate the deviation value T between the actual ambient dew point temperature of the cascade hall and the dew point temperature control target value;

[0009] Step 2: Determine the return air dew point temperature set value T3 of the air conditioning box according to the deviation between the actual ambient dew point temperature of the cascade hall and the dew point temperature control target value;

[0010] Step 3: Automatically obtain the return air dry bulb temperature T4 based on the return air dew point temperature set value T3, and write it into the air conditioning box PLC program as the set value;

[0011] Step 4: The air conditioning site PLC module automatically converts the return air dew point temperature setting value T3 according to the set return air dry bulb temperature T4, thereby realizing automatic adjustment of the air conditioning unit compressor load.

[0012] The step 1 is specifically as follows:

[0013] Let T1 = MAX{t1, t2, t3, ... t n}; where t1, t2, t3, ... t n is the value of all dew point temperature measuring points; by comparing, the maximum value of multiple groups of cascade hall dew point temperature measuring points is obtained;

[0014] T2 = dew point temperature control target value;

[0015] The deviation value T=T1-T2 between the maximum value T1 of the dew point temperature measurement point of the cascade hall and the dew point temperature control target value T2 is calculated as the deviation value between the actual ambient dew point temperature and the dew point temperature control target value.

[0016] The step 2 is specifically as follows:

[0017] Step 2.1: When T1-T2≤0.5℃, the return air dew point temperature setting value of the air conditioning box is T3 = the return air dew point temperature of the air conditioning box - 0.5℃;

[0018] Step 2.2: When T1-T2>0.5, the return air dew point temperature setting value of the air conditioning box is T3=the return air dew point temperature of the air conditioning box-(T1-T2).

[0019] The step 3 is specifically as follows: according to the enthalpy-humidity query chart, the return air dew point temperature setting value T3 and the current relative humidity, the return air dry-bulb temperature T4 is automatically obtained by array coordinate point query.

[0020] The array coordinate point query method is that a certain humidity and a certain dew point temperature correspond to a unique dry bulb temperature.

[0021] The step 4 is specifically as follows: the air conditioning site PLC module automatically converts the return air dew point temperature setting value T3 according to the set return air dry bulb temperature T4 and the current ambient relative humidity, thereby realizing automatic adjustment of the air conditioning unit compressor load.

[0022] In step 4, the return air dew point temperature setting value T3 = air conditioning box return air dew point temperature - (T1-T2), T1-T2>0.5°C, the return air dew point temperature deviates from the setting value by more than 0.5°C, and the air conditioning box PLC automatically increases the air conditioning unit compressor load.

[0023] The beneficial technical effects of the present invention are:

[0024] 1. Significantly reduce manual calculations, and delegate the complex conversion between dew point temperature, dry bulb temperature and relative humidity to a fixed interlocking script program, thus improving work efficiency;

[0025] 2. Incorporate the dew point temperature of the cascade hall, the primary control target of the air conditioning system, into the air conditioning system compressor load adjustment method to further reduce the risk of the cascade hall dew point temperature exceeding the limit;

[0026] 3. The load of the air-conditioning box compressor is automatically increased or decreased according to the changes in the cooling capacity demand of the cascade hall, and the control mode of the air-conditioning equipment is optimized in real time to achieve energy-saving operation of the air-conditioning equipment;

[0027] 4. The development and successful application of the load regulation strategy for the compressor of the uranium enrichment auxiliary process air-conditioning box is of great strategic significance to the independent development of intelligent control technology for the auxiliary process air-conditioning system in the uranium enrichment industry. It has also created good economic benefits for uranium enrichment enterprises and laid a solid foundation for the long-term stable operation of the main equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a flow chart of a method for adjusting the load of a compressor in an air-conditioning box for a uranium enrichment auxiliary process provided by the present invention. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0030] The present invention provides a method for regulating the load of air conditioning compressors in a uranium enrichment auxiliary process. This method associates the dew point temperature of the cascade hall with the load regulation strategy for the air conditioning compressors. Based on the deviation between the maximum value of multiple groups of dew point temperature measurement points within a cluster in the main process hall and the air conditioning system's dew point temperature control target, the load of the air conditioning compressors is adjusted in real time, thereby adjusting the cooling capacity of the air conditioning system. When the dew point temperature deviation is large, the air conditioning compressor load is increased, increasing the cooling capacity and achieving effective regulation and control of the cascade hall's dew point temperature. When the dew point temperature deviation is small or below the control target, the air conditioning compressor load is reduced, achieving energy-saving operation of the air conditioning equipment.

[0031] like Figure 1 As shown, a method for adjusting the load of a compressor in an air-conditioning box for a uranium enrichment auxiliary process according to the present invention specifically comprises the following steps:

[0032] Step 1: Calculate the deviation value T between the actual ambient dew point temperature of the cascade hall and the dew point temperature control target value

[0033] Compare and obtain the maximum value T1 of the dew point temperature measurement points of multiple cascade halls within a certain air-conditioning group, and compare it with the control target value T2 of the dew point temperature of the cascade hall;

[0034] Let T1 = MAX{t1, t2, t3, ... t n}; where t1, t2, t3, ... t n The values of all dew point temperature measurement points in the area under the jurisdiction of the air conditioning group are obtained by comparison; the maximum value of the dew point temperature measurement points of multiple groups of cascade halls within a certain air conditioning group is obtained;

[0035] T2 = dew point temperature control target value of the area under the jurisdiction of the air conditioning group;

[0036] T = T1-T2 is the deviation between the actual ambient dew point temperature and the control target, which can also be understood as the demand for cooling capacity by the on-site environment. The greater the difference between the two, the greater the demand for cooling capacity by the environment.

[0037] Step 2: Determine the return air dew point temperature setting value T3 of the air conditioning box according to the deviation between the actual ambient dew point temperature of the cascade hall and the dew point temperature control target value.

[0038] Step 2.1: When T1-T2≤0.5°C, set the return air dew point temperature of the air conditioning box to T3 = the return air dew point temperature of the air conditioning box - 0.5°C. At this time, the air conditioning site PLC detects that the return air dew point temperature is higher than the set value and starts the air conditioning compressor. At the same time, because the return air dew point temperature deviates from the set value by no more than 0.5°C, the air conditioning compressor operates at the lowest load. This ensures that when the ambient dew point temperature in the area under the jurisdiction of the air conditioning group is lower than the control target or higher than the control target but the deviation does not exceed 0.5°C, the air conditioning compressor operates at a low load, reducing energy consumption.

[0039] Step 2.2: When T1-T2>0.5, that is, the maximum value of the cluster dew point temperature - the cascade hall dew point temperature control target value>0.5°C, in order to increase the air conditioning compressor load, it is necessary to set the air conditioning box return air dew point temperature set value T3=air conditioning box return air dew point temperature-(T1-T2);

[0040] Step 3: Write a group script program to automatically obtain the return air dry bulb temperature T4 according to the return air dew point temperature setting value T3 and the current relative humidity, and write it into the air conditioning box PLC program as the setting value

[0041] A group script program was written to express the enthalpy-humidity query chart (as shown in Table 1) in a logical program using an array coordinate point query method (i.e., a certain humidity and a certain dew point temperature correspond to a unique dry-bulb temperature). This program was placed on the upper platform and automatically obtained the return air dry-bulb temperature T4 based on the return air dew point temperature set value T3 and the current relative humidity. This was then written into the air conditioning box PLC program as the set value.

[0042] Table 1 Dry-bulb and wet-bulb temperature table

[0043] Dry-bulb temperature / humidity conversion table

[0044] Dry-bulb thermometer

[0045]

[0046] Step 4: The air conditioning site PLC module automatically converts the return air dew point temperature setting value T3 according to the set return air dry bulb temperature T4 and the current ambient relative humidity, realizing automatic adjustment of the air conditioning unit compressor load.

[0047] At this point, the air conditioning on-site PLC module automatically converts the return air dew point temperature setpoint T3 based on the set return air dry-bulb temperature T4 and the current ambient relative humidity. Since the return air dew point temperature setpoint T3 = the return air dew point temperature of the air conditioning unit - (T1-T2), and T1-T2 > 0.5°C, the return air dew point temperature deviates from the setpoint by more than 0.5°C, and the air conditioning unit PLC automatically increases the air conditioning unit compressor load. The greater the difference between T1-T2, the greater the deviation between the return air dew point temperature detected by the air conditioning unit PLC and the setpoint, and the higher the air conditioning unit compressor load, achieving automatic increase in the air conditioning unit's cooling capacity in response to increased environmental demand, effectively reducing the risk of dew point temperature exceeding the limit.

[0048] The present invention has been described in detail above with reference to the accompanying drawings and embodiments. However, the present invention is not limited to the above embodiments. Various modifications can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Any content not described in detail in the present invention may be adapted from existing technologies.

Claims

1. A method for adjusting the load of a compressor in an air-conditioning box for a uranium enrichment auxiliary process, characterized in that: The method specifically comprises the following steps: Step 1: Calculate the deviation value T between the actual ambient dew point temperature of the cascade hall and the dew point temperature control target value; Step 2: Determine the return air dew point temperature set value T3 of the air conditioning box according to the deviation between the actual ambient dew point temperature of the cascade hall and the dew point temperature control target value; Step 3: According to the return air dew point temperature set value T3, the return air dry bulb temperature T4 is automatically obtained and written into the air conditioning box PLC program as the set value; Step 4: The air conditioning on-site PLC module automatically converts the return air dew point temperature setting value T according to the set return air dry bulb temperature T4. 3， Realize automatic adjustment of compressor load of air-conditioning unit; The step 1 is specifically as follows: Let T1 = MAX{t1, t2, t3, ... t n }; where t1, t2, t3, ... t n is the value of all dew point temperature measuring points; by comparing, the maximum value of multiple groups of cascade hall dew point temperature measuring points is obtained; T2 = dew point temperature control target value; Calculate the deviation value T=T1-T2 between the maximum value T1 of the dew point temperature measurement point in the cascade hall and the dew point temperature control target value T2 as the deviation value between the actual ambient dew point temperature and the dew point temperature control target value; The step 2 is specifically as follows: Step 2.1: When T1-T2≤0.5℃, the return air dew point temperature setting value of the air conditioning box is T3 = the return air dew point temperature of the air conditioning box - 0.5℃; Step 2.2: When T1-T2>0.5, the return air dew point temperature setting value of the air conditioning box is T3 = the return air dew point temperature of the air conditioning box - (T1-T2); The step 3 is specifically as follows: based on the enthalpy-humidity query chart, the return air dew point temperature setting value T3 and the current relative humidity, the return air dry-bulb temperature T4 is automatically obtained through an array coordinate point query method; the array coordinate point query method is that a certain humidity and a certain dew point temperature correspond to a unique dry-bulb temperature.

2. The method for adjusting the load of a compressor in an air-conditioning box for a uranium enrichment auxiliary process according to claim 1, wherein: The step 4 is specifically as follows: the air conditioning site PLC module automatically converts the return air dew point temperature setting value T according to the set return air dry bulb temperature T4 and the current ambient relative humidity. 3， Realize automatic adjustment of compressor load of air-conditioning unit.

3. The method for adjusting the load of a compressor in an air-conditioning box for a uranium enrichment auxiliary process according to claim 2, wherein: In step 4, the return air dew point temperature setting value T3 = air conditioning box return air dew point temperature - (T1-T2), T1-T2>0.5°C, the return air dew point temperature deviates from the setting value by more than 0.5°C, and the air conditioning box PLC automatically increases the air conditioning unit compressor load.

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