CN101303273A - Fault detection method and device for heat pump unit - Google Patents

Abstract

The invention discloses a heat pump unit failure detection method and its device. The method is as follows: a. Measure the inlet water temperature, the outlet water temperature, the inlet refrigerant temperature and the outlet refrigerant temperature of the first water-cooled heat exchanger respectively with a temperature sensor; The temperature sensor measures the inlet refrigerant temperature, outlet refrigerant temperature, inlet air temperature and outlet air temperature of the air-cooled heat exchanger or the inlet water temperature, outlet water temperature, inlet refrigerant temperature and outlet refrigerant temperature of the second water-cooled heat exchanger ; b. transmit the above temperature to the data acquisition card or digital recorder; c. the microcomputer reads the temperature signal on the data acquisition card or the temperature data recorded by the digital recorder, and runs the fault detection program to detect and analyze the fault of the heat pump unit , to display fault running status and fault alarm. The invention is a fault detection method for a heat pump unit with simple arrangement of measuring points, easy operation and realization, and a device for realizing the method has simple structure and reliable performance.

Description

Fault detection method and device for heat pump unit

technical field

The invention relates to a fault detection method, in particular to a heat pump unit fault detection method, and also relates to a device for realizing the method.

Background technique

The heat pump unit is generally a compressed air-water heat pump unit and a compressed water-water heat pump unit. The compressed air-water heat pump unit includes a first water-cooled heat exchanger, a four-way valve, a compressor, a gas-liquid separator and a regenerator. , dry filter, liquid receiver, air-cooled heat exchanger and fan; the compressed water-water heat pump unit includes the first water-cooled heat exchanger, four-way valve, compressor, gas-liquid separator and regenerator, dry filter receiver, liquid reservoir and second water-cooled heat exchanger. Heat pump units are playing an increasingly important role in solving the problems of using clean energy, improving energy efficiency and reducing environmental pollution. Due to their outstanding advantages, various heat pump units are widely used in the fields of building heating and air conditioning, waste heat recovery, and refrigeration. But in a heat pump system, the occurrence of a fault can cause the system to operate abnormally and cause performance degradation. Generally speaking, hard faults are easy to detect and judge, while soft faults are difficult to find. The common soft faults of the heat pump unit are: (1) poor heat transfer effect of the air side heat exchanger; (2) reduced water flow of the water side heat exchanger; (3) fouling of the water side heat exchanger; (4) compressor Leakage of suction and exhaust valves; (5) Leakage of refrigerant; (6) Excessive charging of refrigerant; (7) Blockage of high-pressure liquid pipeline; (8) Excessive expansion valve opening; (9) Air or other non-condensable gases. Therefore, it is necessary to strengthen the fault detection of the heat pump, quickly diagnose the location and location of the fault, find out the cause of the fault, and reduce the probability of the fault.

After the heat pump unit fails, the characteristics of the system will change, which will lead to changes in the relationship between the measurable variables of the system.

Contents of the invention

The technical problem to be solved by the present invention is to provide a fault detection method for heat pump units with simple arrangement of measuring points and easy operation and realization.

The second technical problem to be solved by the present invention is to provide a device for realizing the method.

In order to solve the above-mentioned technical problems, the heat pump unit failure detection method provided by the present invention, a. Measure the inlet water temperature, outlet water temperature, inlet refrigerant temperature and outlet refrigerant temperature of the first water-cooled heat exchanger respectively with temperature sensors, respectively Measure the inlet refrigerant temperature, outlet refrigerant temperature, inlet air temperature and outlet air temperature of the air-cooled heat exchanger or the inlet water temperature, outlet water temperature, inlet refrigerant temperature and outlet refrigerant temperature of the second water-cooled heat exchanger; b, The above temperature is transmitted to the data acquisition card or digital recorder; c. The microcomputer reads the temperature signal on the data acquisition card or the temperature data recorded by the digital recorder, and runs the fault detection program to detect and analyze the fault of the heat pump unit, and display the fault Running status and fault alarm.

In the device for realizing the fault detection method of the heat pump unit provided by the present invention, 8 temperature sensors corresponding to each temperature detection point are electrically connected to 1 microcomputer through an 8-channel data acquisition card or data recorder, and run on the microcomputer. There is a fault detection procedure based on principal component analysis.

Described temperature sensor is platinum resistance or thermocouple, thermistor, copper resistance temperature sensor.

The heat pump unit fault detection method and its device adopt the above-mentioned technical scheme, utilize the characteristic that the soft fault of the heat pump unit will cause the relationship between the measured variables to change, and the eight temperature sensors are platinum resistance (or thermocouple, thermistor, copper resistance) temperature sensors, One part is placed under the insulation layer of the water or refrigerant inlet and outlet pipes of the heat pump unit heat exchanger, and pasted on the outer wall of the pipe, and the other part is suspended at the air inlet and outlet of the heat exchanger. Therefore, the eight temperature sensors actually measure the wall temperature of the corresponding pipe or the air temperature at the inlet and outlet. The 8 temperature sensors are connected to the 8 channels of the 8-channel data acquisition card, or connected to the 8-channel digital recorder.

The microcomputer reads the temperature signal on the data acquisition card, or the temperature data recorded by the digital recorder, and runs the fault detection program to model and analyze the fault detection of the heat pump unit.

The fault detection program is compiled based on the principal component analysis method and specially used in this patent system. It has the functions of principal component modeling, optimal principal component determination, fault detection and fault prompting and alarming. The fault detection program uses the temperature data measured under normal and stable conditions to establish the principal component model of the heat pump unit, determine the number of principal components, and calculate the detection threshold.

After the principal component model is established, read the temperature measurement data under operating conditions, perform fault detection and analysis, and display the fault operating status and fault alarm.

The variables that need to be measured in this patent are all temperature, the number of measured variables is small, the required temperature measuring points are arranged simply, and it is easy to operate and realize; this patent adopts the principal component analysis method, and uses the measured data under normal steady-state conditions to extract the variables of the heat pump unit The correlation between them is used to realize the fault detection under the fault condition.

This patent is applicable to the refrigeration and heating working conditions of the compressed air-water heat pump unit and the compressed water-water heat pump unit and the fault detection of the compression refrigerator.

To sum up, the present invention is a fault detection method for heat pump units with simple arrangement of measuring points, easy operation and realization, and the device for realizing the method has simple structure and reliable performance.

Description of drawings

Fig. 1 is a block diagram of fault detection of heat pump unit of the present invention;

Figure 2 is a layout diagram of the temperature measuring points of the air-water heat pump unit.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

Referring to Fig. 1, 8 platinum resistance (or thermocouple, thermistor, copper resistance) temperature sensors 9 corresponding to each temperature detection point are electrically connected to a microcomputer 11 through an 8-channel data acquisition card or data recorder 10 , running in the microcomputer 11 is a fault detection program based on principal component analysis.

Table 1 shows the measurement variables measured by eight platinum resistance (or thermocouple, thermistor, copper resistance) temperature sensors of different heat pump units under different working conditions. Their distribution positions in the air-water heat pump unit are shown in Figure 2. For the water-water heat pump unit, the surface heat exchanger in Figure 2 becomes the second plate heat exchanger, and T7 and T8 measure the water temperature at the inlet and outlet of the second plate heat exchanger.

Table 1 Measured variables of the temperature sensor

The present invention will be further described below through the arrangement of temperature measuring points of the air-water heat pump unit in the cooling state.

Referring to Figure 1 and Figure 2, the compressed air-water heat pump unit includes a first plate water-cooled heat exchanger 1, a four-way valve 3, a compressor 2, a gas-liquid separator and a regenerator 8, a dry filter 7, a liquid storage Device 4, surface air-cooled heat exchanger 5, fan 6 and throttle valve 11, and 8 platinum resistors (or thermocouples, thermistors, copper resistors) temperature sensors 9 respectively measure the inlet water temperature of the first plate heat exchanger 1 T1, outlet water temperature T2, inlet refrigerant temperature T4, and outlet refrigerant temperature T3, respectively measure the inlet refrigerant temperature T5, outlet refrigerant temperature T6, inlet air temperature T7, and outlet air temperature T8 of the surface heat exchanger 5 with temperature sensors 6 platinum resistors (or thermocouples, thermistors, copper resistors) temperature sensors 9 are respectively placed under the insulation layer of the water or refrigerant inlet and outlet pipes of the first plate heat exchanger 1 and surface heat exchanger 5, and Pasted on the outer wall of the pipeline, two platinum resistance (or thermocouple, thermistor, copper resistance) temperature sensors 9 are respectively suspended at the air inlet and outlet of the surface heat exchanger 5 . Therefore, the eight platinum resistance (or thermocouple, thermistor, copper resistance) temperature sensors 9 actually measure the temperature of the pipe wall or the air temperature at the inlet and outlet. 8 platinum resistors (or thermocouples, thermistors, copper resistors) temperature sensors 9 are connected to the 8 channels of the 8-channel data acquisition card, or connected to the 8-channel digital recorder.

The microcomputer 12 reads the temperature signal on the data acquisition card 11, or the temperature data recorded by the digital recorder 11, and runs the fault detection program to perform modeling and fault detection analysis on the heat pump unit.

The fault detection program is compiled based on the principal component analysis method and specially used in this patent system. It has the functions of principal component modeling, optimal principal component determination, fault detection and fault prompting and alarming. The fault detection program uses the temperature data measured under normal and stable conditions to establish the principal component model of the heat pump unit, determine the number of principal components, and calculate the detection threshold.

After the principal component model is established, read the temperature measurement data under operating conditions, perform fault detection and analysis, and display the fault operating status and fault alarm.

For the water-water heat pump unit, the surface air-cooled heat exchanger 5 in Fig. 2 becomes the second plate water-cooled heat exchanger, and T7 and T8 measure the inlet and outlet water temperatures of the second plate water-cooled heat exchanger.

This patent is applicable to the refrigeration and heating working conditions of the compressed air-water heat pump unit and the compressed water-water heat pump unit and the fault detection of the compression refrigerator.

Claims (4)

1, a kind of source pump fault detection method, it is characterized in that: a, with temperature sensor measure respectively first water cooling heat exchanger inlet water temperature, the outlet water temperature, inlet refrigerant temperature and outlet refrigerant temperature, with temperature sensor measure respectively air cooling heat exchanger inlet refrigerant temperature, the outlet refrigerant temperature, EAT and the leaving air temp or second water cooling heat exchanger inlet water temperature, the outlet water temperature, inlet refrigerant temperature and outlet refrigerant temperature; B, said temperature is transferred to data collecting card or digital recorder; The temperature data of temperature signal on c, the microcomputer reading of data capture card or digital recorder record, and the operation troubles trace routine is carried out fault detection analysis to source pump, demonstration failure operation state and fault alarm.

2, source pump fault detection method according to claim 1, it is characterized in that: a described temperature sensor part places the water of heat interchanger or cold-producing medium to import and export below the heat-insulation layer of pipe, and be pasted on the pipeline outer wall, or a part is suspended in the air ports place of heat interchanger.

3, realize the device of the described source pump fault detection method of claim 1, it is characterized in that: 8 temperature sensors corresponding with each temperature detecting point are electrically connected with 1 microcomputer (12) by one 8 channel data capture card or datalogger (11), and moving at described microcomputer (12) has 1 fault detection program based on principal component analysis (PCA).

4, the device of realization source pump fault detection method according to claim 3 is characterized in that: described temperature sensor is platinum resistance or thermopair, thermistor, copper resistance temperature sensor (9).

Images