Variable frequency control PVDF direct cooling unit energy saving system

Abstract

The utility model discloses a kind of PVDF direct-cooling unit energy-saving systems of frequency conversion control, including core refrigeration component, control module, monitoring and security component, circulation and connecting component.Core refrigeration component is constituted by evaporator, compressor, condenser, throttling valve;Control module is equipped with frequency converter and PLC controller, frequency converter is adjusted compressor speed according to cold load, and PLC is overall machine operation;Circulation component is configured with chilled water inlet and outlet, cooling water inlet and outlet and refrigerant pipeline, valve is respectively laid on pipeline;Monitoring security component includes temperature sensor and safety valve.Each sensor, safety valve, regulating valve and frequency converter are interconnected with PLC signal.This system is matched load by frequency conversion, multiple valve collaborative control, double-point pressure safety protection, real-time acquisition water temperature signal dynamic adjustment unit operating condition, reduce invalid energy consumption, improve PVDF direct-cooling unit operating stability and energy-saving effect.

Description

Technical Field

[0001] This utility model relates to the field of refrigeration equipment and energy-saving control technology in chemical production, specifically to an energy-saving system for a frequency-controlled PVDF direct-cooling unit. Background Technology

[0002] In the PVDF production process, the stability and efficiency of the cooling process play a decisive role in product quality and production benefits. However, existing PVDF direct-cooling units have many problems that urgently need to be addressed. From a safety perspective, the electrical systems of some units do not meet strict explosion-proof standards, posing a risk of serious accidents such as explosions due to electrical faults in the special environment of PVDF production. Simultaneously, inadequate leakage protection and grounding measures can easily lead to electric shock to personnel and damage to equipment. Regarding the cooling medium circulation, the pipelines lack sufficient pressure resistance and reliable pressure relief devices, potentially causing pipeline rupture and other safety issues when system pressure abnormally increases.

[0003] In terms of energy efficiency, traditional direct-cooling units mostly operate at a fixed frequency, making it impossible to adjust in real time according to the dynamic changes in cooling load during PVDF production. This causes the compressor to operate in an unreasonable state for a long time, resulting in not only a large amount of energy waste but also accelerated equipment wear and increased maintenance costs. In addition, unreasonable cooling process design and low heat exchanger efficiency further reduce energy utilization efficiency.

[0004] In terms of equipment configuration, traditional units use ordinary heat exchange tubes, which have limited heat exchange area and poor heat exchange performance, making it difficult to meet the requirements of high-efficiency heat exchange. Furthermore, the monitoring sensors for key parameters such as temperature and pressure are not accurate enough, resulting in imprecise control of the unit and an inability to accurately adjust the cooling capacity. These problems severely restrict the development of PVDF production, making the development of new energy-saving direct-cooling units an urgent priority. Utility Model Content

[0005] The present invention aims to create an energy-saving system for PVDF direct-cooling units with variable frequency control, so as to optimize the problems of traditional direct-cooling units in terms of safety, energy saving and equipment performance.

[0006] Therefore, the present invention adopts the following technical solution: An energy-saving system for a variable frequency controlled PVDF direct-cooling unit includes core refrigeration components, a control module, monitoring and safety components, and circulation and connection components. The detailed structure and function of each sub-part are as follows: The core refrigeration components include an evaporator, a compressor, a condenser, and a throttle valve; the compressor is connected between the evaporator and the condenser, and the throttle valve is connected between the condenser and the evaporator, forming a Freon circulation loop; The control module includes a frequency converter and a PLC controller. The frequency converter is used to adjust the compressor speed according to the cooling load demand, and the PLC controller is used to monitor and coordinate the system operation. The circulation and connection components include a chilled water inlet G1, a chilled water outlet G2, a cooling water inlet G3, a cooling water outlet G4, a Freon pipeline G, a cooling regulating valve F1, and a suction regulating valve F2. The chilled water inlet G1 and chilled water outlet G2 are located on the evaporator, the cooling water inlet G3 and cooling water outlet G4 are located on the condenser, the cooling regulating valve F1 is located on the cooling water inlet G3, and the suction regulating valve F2 is located on the Freon pipeline G. The monitoring and safety components include a temperature sensor T, a first safety valve A1, and a second safety valve A2. The temperature sensor T is located at the chilled water outlet G2, the first safety valve A1 is located on the evaporator, and the second safety valve A2 is located on the condenser. The temperature sensor T, the first safety valve A1, and the second safety valve A2 are respectively connected to the PLC controller. The PLC controller is connected to the frequency converter. The cooling regulating valve F1 and the suction regulating valve F2 are also connected to the PLC controller.

[0007] Core Refrigeration Components: The evaporator, as a key component in the refrigeration system for absorbing heat, allows low-temperature, low-pressure liquid Freon to absorb heat from the chilled water, vaporizing into low-temperature, low-pressure gaseous Freon, thus cooling the chilled water. The compressor compresses the low-temperature, low-pressure gaseous Freon, transforming it into high-temperature, high-pressure gaseous Freon, providing power for the refrigeration cycle. The condenser transfers heat from the high-temperature, high-pressure gaseous Freon to the cooling water, condensing it into high-temperature, high-pressure liquid Freon. The expansion valve reduces the pressure of the high-temperature, high-pressure liquid Freon, transforming it into low-temperature, low-pressure liquid Freon, which then re-enters the evaporator, completing the refrigeration cycle.

[0008] Control Module: The frequency converter can monitor the cooling load demand during the PVDF production process in real time and automatically adjust the compressor speed accordingly. When the cooling load is low, the compressor speed is reduced to decrease the cooling capacity output and avoid energy waste; when the cooling load is high, the compressor speed is increased to increase the cooling capacity. The PLC controller provides comprehensive monitoring and coordinated control of the entire system operation. It interacts with devices such as the frequency converter and temperature sensors, and precisely regulates the working status of each component based on preset parameters and actual operating conditions.

[0009] Monitoring and Safety Components: Temperature sensors monitor system temperature parameters in real time, providing accurate temperature data to the frequency converter and PLC controller for precise adjustment of cooling capacity. The first and second safety valves are installed at high-pressure points in the system. When the system pressure exceeds a set value, they automatically open to release pressure, preventing damage to equipment and pipelines due to excessive pressure and ensuring safe system operation.

[0010] Circulation and Connection Components: Chilled water enters the evaporator through the chilled water inlet, exchanges heat with the Freon, and then flows out from the chilled water outlet, providing cooling for the PVDF production equipment. Cooling water enters the condenser through the cooling water inlet, absorbs heat from the Freon, and then flows out from the cooling water outlet. Freon pipelines are used to transport Freon, enabling its circulation among various components. Cooling regulating valves and suction regulating valves can adjust the cooling water flow rate and Freon suction volume according to the actual needs of system operation, further optimizing system operating efficiency.

[0011] The beneficial effects of this utility model are as follows: Temperature sensors monitor temperatures in real time and transmit the data to the PLC controller and intelligent frequency converter, automatically adjusting the compressor speed according to cooling load requirements to achieve precise cooling and energy saving. Chilled water and cooling water exchange heat through the evaporator and condenser, respectively, while liquid Freon is recycled. The system has multiple protection mechanisms to ensure stable and safe operation, and performance can be further optimized by adjusting the cooling regulating valve and suction regulating valve. Attached Figure Description

[0012] Figure 1 is a schematic diagram of the energy-saving system of the PVDF direct-cooling unit with frequency conversion control according to this utility model.

[0013] In the diagram: 1 - Evaporator; 2 - Compressor; 3 - Condenser; 4 - Throttling valve; 5 - Frequency converter; 6 - PLC controller; G1 - Chilled water inlet; G2 - Chilled water outlet; G3 - Cooling water inlet; G4 - Cooling water outlet; T - Temperature sensor; A1 - First safety valve; A2 - Second safety valve; G - Freon pipeline; F1 - Cooling regulating valve; F2 - Suction regulating valve. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings: like Figure 1 As shown, a variable frequency controlled PVDF direct-cooling unit energy-saving system is described. In practical applications, the variable frequency controlled PVDF direct-cooling unit energy-saving system of this utility model requires proper operation and installation.

[0015] Inside the PVDF production workshop, the direct-cooling unit energy-saving system is installed in a suitable location near the PVDF production equipment, ensuring that the connections of chilled water pipes, cooling water pipes, and Freon pipes G are secure and well-sealed, while also ensuring that the electrical wiring connections comply with safety regulations.

[0016] Before starting the system, check whether all components are installed in place, whether the first safety valve A1 and the second safety valve A2 are working properly, and whether monitoring devices such as the temperature sensor T can accurately collect data.

[0017] Once PVDF production begins, temperature sensor T monitors the system temperature in real time and transmits the data to PLC controller 6 and frequency converter 5. Simultaneously, frequency converter 5 obtains the cooling load requirements during the production process through information exchange with the PVDF production equipment.

[0018] Based on the collected data, the frequency converter 5 automatically adjusts the speed of the compressor 2. For example, if PVDF production is in the early stage of reaction and the cooling load demand is small, the frequency converter 5 reduces the speed of the compressor 2 to reduce the cooling capacity accordingly and avoid excessive energy consumption; when production enters the stage of intense reaction and the cooling load demand increases, the frequency converter 5 increases the speed of the compressor 2 to increase the cooling capacity and meet the production demand.

[0019] During the refrigeration cycle, chilled water flows into evaporator 1 from chilled water inlet G1, where it exchanges heat with the low-temperature, low-pressure liquid refrigerant. After its temperature decreases, it flows out from chilled water outlet G2, cooling the PVDF production equipment. High-temperature, high-pressure gaseous refrigerant discharged from compressor 2 enters condenser 3. Cooling water flows into condenser 3 from cooling water inlet G3, carrying away the heat from the refrigerant and condensing it into a liquid state, which then flows out from cooling water outlet G4. The liquid refrigerant, after being throttled and depressurized by expansion valve 4, re-enters evaporator 1, completing one refrigeration cycle.

[0020] During system operation, if the temperature sensor T detects an abnormal temperature or the first safety valve A1 and the second safety valve A2 detect that the system pressure exceeds the set value, the PLC controller 6 will immediately take corresponding measures, such as adjusting the compressor speed 2, opening the first safety valve A1 and the second safety valve A2 to release pressure, to ensure the stable and safe operation of the system. Simultaneously, operators can fine-tune the cooling water flow rate and refrigerant intake by adjusting the cooling regulating valve F1 and the suction regulating valve F2 according to actual conditions, further optimizing the system's energy-saving effect and cooling performance.

Claims

1. An energy-saving system for a frequency converter-controlled PVDF direct-cooling unit, characterized in that, Includes core refrigeration components, control modules, monitoring and safety components, and circulation and connection components; The core refrigeration components include an evaporator (1), a compressor (2), a condenser (3), and a throttle valve (4); the compressor (2) is connected between the evaporator (1) and the condenser (3), and the throttle valve (4) is connected between the condenser (3) and the evaporator (1), forming a Freon circulation loop; The control module includes a frequency converter (5) and a PLC controller (6). The frequency converter (5) is used to adjust the speed of the compressor (2) according to the cooling load demand, and the PLC controller (6) is used to monitor and coordinate the operation of the system. The circulation and connection components include a chilled water inlet (G1), a chilled water outlet (G2), a cooling water inlet (G3), a cooling water outlet (G4), a Freon pipe (G), a cooling regulating valve (F1), and a suction regulating valve (F2). The chilled water inlet (G1) and chilled water outlet (G2) are located on the evaporator (1), the cooling water inlet (G3) and cooling water outlet (G4) are located on the condenser (3), the cooling regulating valve (F1) is located on the cooling water inlet (G3), and the suction regulating valve (F2) is located on the Freon pipe (G). The monitoring and safety components include a temperature sensor (T), a first safety valve (A1), and a second safety valve (A2). The temperature sensor (T) is located at the chilled water outlet (G2), the first safety valve (A1) is located on the evaporator (1), and the second safety valve (A2) is located on the condenser (3). The temperature sensor (T), the first safety valve (A1), and the second safety valve (A2) are respectively connected to the PLC controller (6) via signal. The PLC controller (6) is also connected to the frequency converter (5) via signal. The cooling regulating valve (F1) and the suction regulating valve (F2) are also connected to the PLC controller (6) via signal.

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