Simple remote controller applied to lithium bromide absorption type unit

Abstract

A simple remote controller applied to a lithium bromide absorption type unit belongs to the technical field of lithium bromide absorption type refrigeration and mainly has the functions of remotely controlling start and stop of the unit and automatically starting and stopping the unit in a timing manner. Data states of the units and accessory equipment are monitored through communication, and starting and stopping functions of the multiple units are automatically controlled; a system cold water pump and cooling water pump frequency conversion signal function is provided; a cooling tower temperature control function; an anti-freezing operation function; an energy-saving mode operation function; an exception handling and COP detection function; and a unit start-stop function and the like. The remote controller is mainly composed of a display operation unit, a data communication unit, a frequency conversion signal output unit, a digital I / O control unit, a main control unit and the like. The remote controller has the advantages of being economical, practical, complete in function and capable of meeting various requirements of users.

Description

Technical Field

[0001] The utility model belongs to the technical field of lithium bromide absorption refrigeration, and in particular relates to a simple remote controller applied to a lithium bromide absorption unit. Background Art

[0002] Lithium bromide absorption chiller is a common air conditioning and refrigeration equipment, mainly providing cold and hot sources for large centralized air conditioning systems and other places that need hot and cold water. It is widely used in various fields of the national economy such as office buildings, hotels, shopping malls, theaters, gymnasiums, factories, oil fields, etc. Absorption chillers that comprehensively utilize waste heat energy and composite energy use factory waste heat, waste heat, solar energy, etc. to save energy and reduce emissions. They are widely used in petrochemical, steel, chemical, textile, refinery, chemical fiber, fertilizer plant, pharmaceutical, thermal power, electronics and other industrial and mining enterprises.

[0003] At present, most of the remote controllers for lithium bromide absorption units on the market have simple functions such as single-unit start and stop, fault reset, etc. That is, the operation buttons are simply transferred to the remote controller. Disadvantages: simple functions, no auxiliary expansion functions. How to make the remote controller of lithium bromide absorption unit solve the user unit and auxiliary equipment control in a low-cost way, and significantly improve the safety and economic operation effect of lithium bromide absorption unit, has become an urgent problem to be solved. Summary of the invention

[0004] In order to solve the above-mentioned problems, the utility model proposes: a simple remote control for lithium bromide absorption unit, including a display operation unit, a data communication unit, a frequency conversion signal output unit, a digital I / O control unit, and a main control unit, wherein the display operation unit, the data communication unit, the frequency conversion signal output unit, and the digital I / O control unit are all connected to the main control unit.

[0005] Furthermore, a plurality of lithium bromide absorber units are connected to the digital I / O control unit.

[0006] Furthermore, a plurality of lithium bromide absorber units are connected to the data communication unit.

[0007] Furthermore, the data communication unit is connected to a remote host computer.

[0008] Furthermore, the digital I / O control unit is connected to an outside air temperature switch, a cold water pump, a cooling water pump, and a cooling tower.

[0009] Furthermore, the frequency conversion signal output unit is connected to a frequency converter.

[0010] The beneficial effects of the utility model are as follows: the utility model adopts an intelligent control system with a high-performance microprocessor as the main body. It can realize the analysis and control of various data collection, relevant data setting, remote start and stop, number control, abnormal alarm and reset, cooling tower temperature control, energy-saving operation, anti-freeze operation, frequency conversion signal processing, COP state detection, etc. of lithium bromide absorption units. Moreover, compared with the DCS centralized control system, the cost is very advantageous. It can meet the user's demand for centralized control of the lithium bromide absorption unit room, and can improve the safety and economic operation effect of the unit through the reasonable use of the remote control function. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a structural diagram of a simple remote control system used in the lithium bromide absorption unit of the utility model.

[0012] Figure 2 This is a dimensional diagram of the appearance of a simple remote control used in the lithium bromide absorption unit of the utility model. DETAILED DESCRIPTION

[0013] In order to make the technical means adopted by the utility model and the purpose achieved easy to understand, the utility model is further explained in combination with a specific implementation method below. A simple remote control for lithium bromide absorption unit application, the remote control is mainly composed of a display operation unit, a data communication unit, a frequency conversion signal output unit, a digital I / O control unit, a main control unit, etc.

[0014] The display operation unit is composed of a liquid crystal display and selection buttons. The buttons are respectively: operation, energy-saving operation, program operation, number of units control, item, selection, return, increase, and decrease.

[0015] The data communication unit consists of a communication master station and a communication slave station. The communication master station is used to read the operating data of each lithium bromide absorption unit; the communication slave station provides the host computer with all the data detected by the remote controller. The communication is MODBUS protocol, and the interface provides two types: RS485 and Ethernet interface.

[0016] The main control unit is an intelligent control system based on a high-performance microprocessor, which can realize the analysis and control of various data collection, relevant data setting, remote start and stop, number control, abnormal alarm and reset, cooling tower temperature control, energy-saving operation, anti-freeze operation, frequency conversion signal processing, COP status detection, etc. of lithium bromide absorption units.

[0017] The frequency conversion output unit remote controller automatically calculates the cold water temperature difference and warm water temperature difference according to the cold and warm room judgment, calculates the frequency value based on the temperature difference signal and the cooling water inlet temperature, and converts them into DC4-20mA signals to provide to the frequency converter. Its logic judgment formula method is the optimal result obtained after hundreds of experiments, and the frequency parameters can be changed according to different unit working conditions.

[0018] The digital I / O control unit has the functions of controlling auxiliary equipment (cold water pump, cooling water pump, cooling tower) to automatically start and stop according to the current operating conditions of the unit, monitoring the outside air temperature to participate in the unit's antifreeze operation, unit start and stop interlocking control and alarm processing.

[0019] like Figure 1 As shown in the figure, the structure diagram of the remote control system is as follows: the display operation unit inside the remote control, the data communication unit, the frequency conversion signal output unit, the digital I / O control unit, the main control unit, etc. The remote control connection system can have multiple lithium bromide absorber units and their auxiliary system components, such as cold water pumps, cooling water pumps, cooling towers, frequency converters, outdoor air temperature switches, and the above host computer monitoring system.

[0020] The cooling tower temperature control function of the utility model: the remote control can control the start and stop of the cooling tower according to the set upper and lower limit temperatures of the cooling water inlet. The remote control communicates with the refrigerator to obtain the current cooling water inlet temperature. When the cooling tower temperature control start and stop is enabled, the remote control communicates with the refrigerator. If the refrigerator is running and the cooling water pump is linked to ON, the cooling tower stops when the cooling water temperature is lower than or equal to the lower limit temperature; the cooling tower starts when the cooling water temperature is higher than or equal to the upper limit. If the remote control communicates with the refrigerator to obtain cooling water linkage or the refrigerator is in a stopped state, the remote control sends a cooling tower stop signal.

[0021] The utility model has frequency conversion control function: the remote controller automatically calculates the temperature difference of cold water and warm water according to the cold and warm rooms, and converts the temperature difference signal and the cooling water inlet temperature signal into 4-20mA signal to supply to the frequency converter.

[0022] Functional description:

[0023] In cold room, PV1 = cold water inlet temperature - cold water outlet temperature. If the cold water inlet temperature is less than the cold water outlet temperature, PV1 = 0.

[0024] When heating, PV1 = warm water outlet temperature - warm water inlet temperature. If the warm water outlet temperature is less than the warm water inlet temperature, PV1 = 0.

[0025] Chilled water pump control: (AO1)

[0026] In cooling room: when the cold water outlet temperature PV2> cold water outlet temperature setting SV1, the analog output AO1 is 20mA;

[0027] When the cold water outlet temperature PV2 < cold water outlet temperature setting SV1, analog output AO1 is

[0028] AO1=0.8*PV1+4(mA).

[0029] In heating mode: when the warm water outlet temperature PV2 < the warm water outlet temperature setting SV2, the analog output AO1 is 20mA;

[0030] When the warm water outlet temperature PV2> warm water outlet temperature setting SV2, analog output AO1 is

[0031] AO1=0.8*PV1+4(mA).

[0032] Cooling water pump control: (AO2)

[0033] Analog output AO2 = 0.32 * PV3 + 4 (mA)

[0034] The inverter frequency is adjusted to 35~50Hz.

[0035] Parameter Description:

[0036] PV1: cold water (warm water) temperature difference;

[0037] PV2: cold water (warm water) outlet temperature;

[0038] PV3: cooling water inlet temperature;

[0039] SV1: cold water outlet temperature setting value; SV2: warm water outlet temperature setting value;

[0040] AO1: cold water (warm water) pump frequency analog output (0~20mA);

[0041] AO2: Cooling water pump frequency analog output (0~20mA);

[0042] The utility model has an antifreeze operation function: according to the state of the antifreeze contact, the state of the cooling and heating room, and the switch setting of the remote controller, the cold water pump circulation or the heating antifreeze operation is performed.

[0043] Working status: If the antifreeze status is valid, the outside air temperature switch is ON, and the remote controller sends a cold water pump start signal according to the lower temperature of the cold water inlet or outlet, if it is less than 5℃. After running for 5 minutes, the status is continuously detected. If the lower temperature of the cold water inlet or outlet is higher than 7℃, the remote controller sends a cold water pump stop signal, otherwise it keeps the cold water pump running signal. If the antifreeze status is invalid, the cold room does not work.

[0044] The utility model has an energy-saving operation function: the operation and stop of the cooling water pump and the cooling tower are controlled according to the operation state of the refrigerant pump, so as to achieve the purpose of saving electric energy.

[0045] Working status: During the communication between the remote controller and the refrigerator, if the refrigerant pump and the combustion signal are stopped, the remote controller will send a cooling water interlock hold signal after ten minutes, and the cooling water pump and cooling tower will stop signal. The remote controller repeatedly detects whether the combustion signal or the refrigerant pump is started. If it is started, the remote controller sends a cooling water pump and cooling tower operation signal, and according to the cooling water interlock hold time delay, the cooling water interlock hold signal is turned on.

[0046] The COP monitoring function of the utility model: when only the cold room is used, if the temperature difference between the cold water inlet and outlet is less than 1°C, 100% combustion, and the regenerator temperature is above 130°C for 30 minutes, it is a COP abnormality and an alarm is displayed. When the COP alarm occurs, the buzzer sounds; during the alarm process, press the buzzer reset button to stop the alarm and the digital tube displays normal data; if the COP alarm is not eliminated within 1 minute, the buzzer will alarm again. When the COP alarm is eliminated, the digital tube displays normal data and the buzzer stops.

[0047] The utility model has the following functions: through communication, the load calculation of each lithium bromide absorption unit, the comparison of the cumulative operation time, the abnormal alarm status and other comprehensive judgments are obtained, and the start and stop signals of the lithium bromide absorption unit are output. When the total load is greater than the set value within the monitoring time, that is, greater than 80% of the initial value, an additional lithium bromide absorption unit is started. When the total load is less than the set value within the monitoring time, that is, less than 50% of the initial value, one lithium bromide absorption unit is stopped. When any of the units has an abnormal alarm, another unit is immediately switched to start operation. The judgment detection cycle of the start and stop unit is set to at least 30min-1h, and the load size is converted and calculated according to the input driving heat source percentage of the lithium bromide absorption unit.

[0048] like Figure 2 As shown, the remote controller of the utility model has a delicate and compact appearance, and its functions are comparable to those of a DCS centralized control system. However, it has a higher cost performance than that of a DCS centralized control system. It is durable and uses a key operation mode, and is suitable for harsh and complex environments of industrial and mining enterprises.

[0049] Summary: The utility model relates to a simple remote control for lithium bromide absorption units. The features are: an intelligent control system based on a high-performance microprocessor. It can realize the analysis and control of various data collection, relevant data setting, remote start and stop, number of units control, abnormal alarm and reset, cooling tower temperature control, energy-saving operation, antifreeze operation, frequency conversion signal processing, COP status detection, etc. of lithium bromide absorption units. And compared with the DCS centralized control system, the cost is very advantageous. The utility model can meet the user's demand for centralized control of the lithium bromide absorption unit room, and can improve the safety and economic operation of the unit through the rational use of the remote control function.

[0050] The above is only a preferred specific implementation method of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and concept of the utility model within the technical scope disclosed by the utility model, which should be covered by the protection scope of the utility model.

Claims

1. A simple remote controller for lithium bromide absorption unit, characterized in that: It includes a display operation unit, a data communication unit, a frequency conversion signal output unit, a digital I / O control unit, and a main control unit, wherein the display operation unit, the data communication unit, the frequency conversion signal output unit, and the digital I / O control unit are all connected to the main control unit.

2. The simple remote controller for the lithium bromide absorption unit as claimed in claim 1, characterized in that: A plurality of lithium bromide absorber units are connected to the digital I / O control unit.

3. The simple remote controller for the lithium bromide absorption unit according to claim 1, characterized in that: A plurality of lithium bromide absorber units are connected to the data communication unit.

4. The simple remote controller for the lithium bromide absorption unit according to claim 1, characterized in that: The data communication unit is connected to a remote host computer.

5. The simple remote controller for the lithium bromide absorption unit according to claim 1, characterized in that: The digital I / O control unit is connected with an outside air temperature switch, a cold water pump, a cooling water pump and a cooling tower.

6. The simple remote controller for lithium bromide absorption unit according to claim 1, characterized in that: The frequency conversion signal output unit is connected to the frequency converter.

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