KR100324561B1 - Apparatus for preventing high pressure in absorption heat pump and method thereof - Google Patents

Abstract

The present invention relates to a high pressure preventing device and a method of an absorption type heat pump capable of preventing abnormal high pressure by indirect purging the flow rate of the solution passing through the GFD based on the gas heat input amount and the inlet / outlet temperature difference of the GFD. .

Absorption heat pump high pressure prevention device of the present invention for this purpose, the GFD inlet temperature sensor 110 is installed at the inlet of the GFD in the regenerator to sense the temperature, and the GFD outlet temperature sensor installed at the outlet of the GFD to sense the temperature ( 120 and the calculated temperature difference between the inlet and outlet of the GFD based on the sensed values of the two temperature sensors 110 and 120, and the estimated heat input based on the control value of the gas valve. In accordance with the microcomputer 130 to indirectly purge the flow rate of the solution passing through the GFD.

Description

Apparatus for preventing high pressure in absorption heat pump and method

The present invention relates to an absorption heat pump, and in particular, to indirectly purge the flow rate of a solution passing through the GFD based on the gas heat input amount and the gas inlet / outlet temperature difference of the GFD (Gas-Fired Desorber) to prevent abnormal high pressure. A high pressure preventing device of an absorption heat pump and a method thereof are provided.

In the general absorption type heat pump, as shown in FIG. 1, a refrigerant vapor is obtained by evaporating a refrigerant from a high-concentration working solution by heat generated in a burner (not shown), and at the same time, the concentration generated by evaporation of some refrigerant is low. The condenser is condensed into a liquid refrigerant by using a regenerator 10 for generating an aqueous refrigerant solution (hereinafter referred to as a "medical solution") and cooling water that is cooled after heat-exchanging heat with external air in an outdoor unit. Condenser 20 and the evaporator 30 to evaporate the liquid refrigerant discharged from the condenser 20 to the refrigerant vapor again by using the cold water of the temperature rise from the indoor unit, and the refrigerant vapor generated in the evaporator 30 Absorber 40 to make a strong concentration of the concentrated solution by the continuous absorption action to allow the drug solution to absorb, and the regenerator (1) of the high pressure portion of the solution of the absorber (40) It consists of the solution pump 50 sent to 0).

GFD (11) for evaporating the refrigerant with a high temperature combustion gas in the regenerator (10) to obtain a refrigerant vapor, and at the same time to generate a high-temperature medicinal solution having a low concentration generated by evaporation of some of the refrigerant, and the refrigerant vapor is evaporated together with the refrigerant vapor. Rectifier 12 for condensing water vapor and rectifying it with refrigerant vapor of high concentration, and an analyzer (13) for increasing the concentration by exchanging the steel solution passing through the absorber 40 with the refrigerant vapor rising from the bottom. It is done.

In the drawings, reference numeral 61 is an outdoor unit air coil, 62 is an indoor unit air coil, and 63 and 64 are cooling water circulation pumps.

Referring to the operation and effect of the general absorption type heat pump configured as described above are as follows.

First, there is an aqueous refrigerant solution, that is, an aqueous ammonia solution, in the regenerator 10, which has a property of evaporating at a lower temperature than water.

Therefore, when the GFD 11 in the regenerator 10 is heated by a burner (not shown), the aqueous ammonia solution is separated into water and ammonia, and the ammonia that has not evaporated at this time is mixed with water lightly. It is called medicinal solution state.

On the other hand, the state that is hardly separated is called a strong solution state, and the pure ammonia separated is subjected to heat exchange with the cooling water while passing through the condenser 20 and the evaporator 30.

At this time, since the regenerator 10 and the condenser 20 form a high pressure part and the evaporator 30 and the absorber 40 form a low pressure part, the ammonia condensed in the condenser 20 immediately passes through the evaporator 30. While the heat exchange is carried out, the ammonia from the evaporator 30 is introduced into the absorber 40, the drug solution mixed with a little ammonia and water produced in the regenerator 10 immediately enters the absorber 40, the evaporator ( The ammonia from 30 is absorbed and converted back into a strong solution.

In order to flow the steel solution back into the regenerator 10, a solution pump 50 for compensating for the pressure difference between the high pressure regenerator 10 and the low pressure absorber 40 is used.

On the other hand, the cooling water is dropped from the evaporator 30 when cooling by the driving principle to send to the indoor unit air coil 62 to perform the cooling, the cooling water cooling the condenser 20 and the absorber 40 is high temperature. Since it is sent to the outdoor unit air coil 61 to cool again.

On the contrary, in the case of heating, cold water whose temperature is increased while passing through the condenser 20 and the absorber 40 is sent to the indoor unit air coil 62 to perform heating, and the coolant that has passed through the evaporator 30 is the outdoor unit air coil 61. Send to.

The above operation is continuously circulated while the system is in equilibrium.

However, when an abnormality occurs in the system in such an absorption type heat pump and overpressure is formed in the high pressure part including the regenerator 10 and the condenser 20, the safety of the system may be greatly affected.

In the related art, for safety reasons, a pressure sensor is directly attached to detect the pressure of the high pressure part, so that excessive pressure is applied to the high pressure part.

However, since the material of the pressure sensor should correspond to the corrosiveness of the ammonia used as the refrigerant, an expensive pressure sensor should be used, which increases the cost of the system.

Therefore, the present invention has been proposed to solve the above problems of the prior art, and in view of the fact that the occurrence of abnormal high pressure is caused by the flow rate of the solution in the GFD, the GFD is passed based on the amount of gas heat input and the temperature difference between the inlet and outlet of the GFD. It is an object of the present invention to provide an apparatus and method for preventing the high pressure of an absorption type heat pump that indirectly purges the flow rate of a solution to prevent abnormal high pressure.

The high pressure prevention method of the present invention for achieving the above object includes a condenser for condensing the refrigerant vapor obtained in the regenerator with a liquid refrigerant, an evaporator for making the liquid refrigerant into the refrigerant vapor, and the refrigerant vapor generated in the evaporator absorbs the chemical solution In the absorption type bottom pump equipped with the absorber to make a strong solution, the difference between the inlet and outlet temperature and the gas heat input amount of the GFD are determined as conditional variables in order to perform the fuzzy inference which can store the basic information as data. A variable determining step of determining a sub variable; A basic information storage step of quantizing and distinguishing an input condition corresponding to a GFD inlet / outlet temperature difference and a gas heat input amount, and calculating and storing an inference result accordingly; When the system is operated, the inlet and outlet temperature difference of the GFD is calculated, and the gas input value is estimated based on the control value of the gas valve, and then the inlet and outlet temperature difference and the estimated input heat quantity are quantized and stored in the basic information storage step. According to the technical means consisting of the GFD solution flow rate estimating step to indirectly purge the flow rate of the solution passing through the GFD.

1 is a block diagram of a general absorption heat pump.

Figure 2 is a block diagram of an absorption type heat pump high pressure preventing device according to the present invention.

3 (a) is a graph of the correlation between the GFD inlet and outlet temperature difference and the gas heat input amount, (b) is a graph of the correlation between the GFD inlet and outlet temperature difference and GFD solution flow rate.

4 is a membership function used for fuzzy inference according to the present invention.

*** Explanation of symbols for the main parts of the drawing ***

10: player 11: GFD

110: GFD inlet temperature sensor 120: GFD outlet temperature sensor

130: micom 131: look-up table

Hereinafter, the present invention will be described with reference to the accompanying drawings.

Figure 2 is a block diagram of a high pressure prevention device of the absorption type heat pump according to the present invention, the GFD inlet temperature sensor 110 is installed at the inlet of the GFD in the regenerator to sense the temperature, and is installed at the outlet of the GFD After calculating the GFD outlet temperature sensor 120 and the temperature difference between the inlet and outlet of the GFD based on the detected values of the two temperature sensors 110 and 120 and estimating the amount of heat input based on the control value of the gas valve. The microcomputer 130 indirectly purges the flow rate of the solution passing through the GFD according to the pre-stored look-up table 131.

Referring to Figures 1 to 4 attached to the operation and effect of the present invention configured as described above are as follows.

3 (A) is a correlation graph of the GFD inlet and outlet temperature difference and the gas heat input amount, Figure 3 (B) is a correlation graph of the GFD inlet and outlet temperature difference and the GFD solution flow rate.

Looking at these two graphs, there is a clear temperature difference between the inlet and the outlet of the GFD 11 during normal operation in which gas is input to the burner and combustion is normally performed, and the flow rate of the solution passing through the GFD 11 is secured to some extent. It is found that the inlet and the outlet of the GFD do not maintain a normal temperature difference when the gas is present and the combustion is not normally performed or when the flow rate of the solution passing through the GFD 11 is sharply reduced.

Therefore, the present invention provides a basic principle that the flow rate of the GFD solution can be estimated from two pieces of information, the gas input amount and the GFD inlet / outlet temperature difference, when a valve capable of proportional control is used as the gas valve for determining the input amount of heat during system operation. Is introduced.

First, in order to perform fuzzy inference that can store basic information as data, the GFD inlet temperature difference and the gas heat input amount are determined as conditional variables, and the GFD solution flow rate is determined as the conclusion variable.

That is, normal combustion is opened by using a proportional control gas valve that can control a certain degree of opening, the frame rod which is a device that can detect the flame when controlling the rotation speed of the preset combustion fan If it detects the presence of a flame, it is regarded as a normal combustion state. In this case, when normal combustion and normal refrigerant circulation occur, the GFD receives heat from the combustion device to transfer heat to the refrigerant, which causes a temperature difference within a specific temperature range between the inlet and the outlet of the GFD. Done.

In addition, the microcomputer 130 quantizes and distinguishes an arbitrary input condition so that the microcomputer 130 can make inference, and calculates the inference result accordingly in the form of a look-up table 131 in the ROM region of the microcomputer 130. Save it so you can find the result in real time.

In this case, since a membership function is required for each variable for fuzzy inference, each membership function is configured as shown in FIG. 4.

On the other hand, the basic rule for fuzzy inference is shown as an example in Table 1 below.

Temperature Charging Calorie very little a little A little little very little moderation Little little little a little Very few moderation Little small A little Very few moderation Little Little A lot of Very few moderation moderation Little

When the system is operated in the basic setting state as described above, the GFD inlet temperature sensor 110 senses the temperature of the GFD 11 inlet in the regenerator 10 and inputs it to the microcomputer 130, and the GFD outlet temperature sensor 120. Detects the temperature of the GFD 11 exit and inputs it to the microcomputer 130.

Then, the microcomputer 130 calculates the inlet / outlet temperature difference of the GFD 11 based on the detected values of the two temperature sensors 110 and 120, and estimates the amount of heat input of the gas based on the control value of the gas valve. The amount of heat is quantized to indirectly purge the flow rate of the solution passing through the GFD 11 according to the pre-stored look-up table 131, and determine the GFD solution flow state in real time by dequantizing the inferred value again.

Here, in the case of fuzzy control, membership function is essentially set at the time of setting the membership function for each control factor, and the physical values for the upper limit and the lower limit are set in advance at the design stage. For example, with respect to the temperature difference, if the value corresponding to the vertex of 'very little' is 10 degrees, the vertex corresponding to 'many' is designated at the design stage as 90 degrees.

As such, when the flow rate of the solution in the GFD 11 is determined, appropriate measures are performed based on this to prevent abnormal high pressure.

That is, since the flow rate of the solution in the GFD 11 causes abnormal high pressure, the GFD solution flow rate is properly adjusted or the system is stopped to prevent a safety accident.

As described above, the present invention can indirectly purge the flow rate of the solution passing through the GFD on the basis of the amount of gas heat input and the inlet / outlet temperature of the GFD, thereby preventing abnormal high pressures in advance. Compared with the prior art, there is no need to use an expensive pressure sensor, thereby reducing the cost of the system.

Claims (2)

Absorption bottom pump with a condenser for condensing the refrigerant vapor obtained from the regenerator with a liquid refrigerant, an evaporator for making the liquid refrigerant into the refrigerant vapor, and an absorber for absorbing the refrigerant vapor generated in the evaporator to form a strong solution. To GFD installed in the regenerator to evaporate the refrigerant with a high temperature combustion gas to obtain a refrigerant vapor, and at the same time to generate a high-temperature medicinal solution with low concentration generated by evaporation of some of the refrigerant at the inlet of the GFD to sense the temperature. Inlet temperature sensor 110, A GFD outlet temperature sensor 120 installed at an outlet of the GFD to sense a temperature; The inlet and outlet temperature difference of the GFD is calculated on the basis of the sensed values of the two temperature sensors 110 and 120, and the heat input is estimated based on the control value of the gas valve, and then the indirect purge inference of the flow rate of the solution passing through the GFD. High pressure prevention device of the absorption heat pump, characterized in that configured to include a microcomputer (130). In order to perform the fuzzy inference that can store the basic information as data, the variable determination step of determining the inlet and outlet temperature difference and gas heat input amount of the GFD as a conditional variable, and determines the GFD solution flow rate as the conclusion variable, A basic information storage step of quantizing and distinguishing an input condition corresponding to the GFD inlet / outlet temperature difference and a gas input amount, and calculating and storing an inference result accordingly; When the system is operated, the inlet / outlet temperature difference of the GFD is calculated, the gas heat input amount is estimated based on the control value of the gas valve, and the calculated inlet / outlet temperature difference and the estimated heat input amount are quantized and stored in the basic information storage step. Method for preventing the high pressure of the absorption type heat pump, characterized in that the GFD solution flow estimating step of indirectly purging the flow rate of the solution passing through the GFD according to the inference result.