EP4269909A1

EP4269909A1 - System for distributing refrigerant to a heat exchanger and method for operation thereof

Info

Publication number: EP4269909A1
Application number: EP23169935.6A
Authority: EP
Inventors: Milosz Wlodarczyk; Marcin Kowacz
Original assignee: Igloo Spolka Z Ograniczona Odpowiedzialnoscia
Current assignee: Igloo Spolka Z Ograniczona Odpowiedzialnoscia
Priority date: 2022-04-26
Filing date: 2023-04-25
Publication date: 2023-11-01

Abstract

A system (1) for supplying cooling medium to a heat exchanger (10) of a heat machine (5) with j-th sections (11, 12, 13, 14) of the heat exchanger (10) and additionally comprising a compressor (4), a condenser (7) and flow lines connecting the j-th sections (11, 12, 13, 14) of the heat exchanger (10) with mentioned units as well as a power supply and control system (2), the system (1) further comprises a set (40) of controlled input shut-off or throttling or expansion valves (41, 42, 43, 44), one of each in the assigned supply flow line (21, 22, 23, 24) of the j-th section (11, 12, 13, 14) of the heat exchanger (10) or a set of controlled output cut-off valves (46, 47, 48, 49), whereas the power and control system (2) has a control system (50) with a controller (70) communicating with the controlled input shut-off valves or throttling or expansion valves (41, 42, 43, 44) and a set (80) of units (81, 82, 83, 84) determining the ratio of evaporation of the cooling medium as well as a set (30) of temperature sensors (31, 32, 33, 34), one of each located nearby an output of the assigned outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) communicating with the controller (70) and receiving distribution of temperature difference at the output of the outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the cooling medium for the purpose of controlling the controlled input shut-off valves (41, 42, 43, 44).

Description

The subject of the invention is a system for supplying a cooling medium to a heat exchanger of a heat machine which is in particular a heat pump, a condensing unit or an air dryer.
The invention also relates to a method for supplying a cooling medium by means of the system for supplying the cooling medium to the heat exchanger of the heat machine, in particular a heat pump, a condensing unit or an air dryer.
The process of supplying a refrigerant or a cooling medium to a heat exchanger, for example an evaporator, in currently used devices consists in supplying the medium by means of a compressor through dividers to the entire exchanger circuit without the possibility of controlling the process of distributing a liquid to individual sections. Commonly used manifolds have a form of a properly shaped set of nozzles, optimized for a given operating point of the heat machine, with strictly defined refrigerant flow parameters, such as density, viscosity, flow rate. This solution is not complicated, it is cheap but not free of defects. The heat machines operating in a large power range, below or above the optimal operating conditions of the above-mentioned simple manifold, show uneven distribution of the refrigerant in the volume of the heat exchanger. This in turn contributes to accelerated overicing of the heat exchanger. This is an undesirable phenomenon, reducing the efficiency of the heat machine.
Furthermore, the correct operation of commonly used manifolds depends on the deviation from the vertical, therefore their operation depends on the correct installation of the heat machine.
The aim of the present invention is to develop a system that enables more efficient use of heat machines by stabilizing the distribution of a refrigerant or a cooling medium by using electronic input throttling valves or input shut-off valves or input expansion valves that precisely regulate the refrigerant supply to evaporators based on temperature sensors and/or pressure prevailing in individual sections of the heat exchanger. Experience shows that the exchanger, for example, in the described case the evaporator, operating at the idle point of operation, shows uneven overicing which propagates quickly therefore may result in a snowball effect propagating and may reduce the efficiency of the device. An icy exchanger causes a lot of problems because the defrosting process takes more time and affects the efficiency of the device.
The idea of the invention is a system for supplying a cooling medium to a heat exchanger of a heat machine with j-th sections of the heat exchanger and comprising a compressor, a condenser and flow lines connecting the j-th sections of the heat exchanger with the compressor and a divider having a supply distribution strip with supply flow lines of the j-th sections, and a return strip with outflowing flow lines of the j-th sections of the heat exchanger, and a power supply and control system, characterised in that the system for supplying the cooling medium to the heat exchanger further comprises a set of controlled input shut-off valves, one of each located in the assigned supply flow line of the j-th section of the heat exchanger or controlled output cut-off valves, one of each located in the assigned outflowing flow line of the j-th section of the heat exchanger, whereas the power and control system has a control system with a controller communicating with the controlled input shut-off valves or the controlled output shut-off valves and a set of temperature sensors, one of each located at an output of the assigned outflowing flow line of the j-th section communicating with the controller receiving a distribution of temperature difference at the output of the outflowing flow lines of the j-th sections of the cooling medium for the purpose of controlling the controlled input shut-off valves or the controlled output shut-off valves.
Preferably, the heat exchanger is a lamellar exchanger or a tubular exchanger or a microchannel exchanger.
In addition, the controller is a programmable logic controller (PLC), whereby the PLC controller comprises a processor with a user program interpreting a status of analog or digital inputs of the processor and stored in a memory of the processor, a temperature/flow average value calculation module, a value comparison module of an average temperature/flow with set values, a module of switching on/off of shut-off or throttling valves comparing the determined current average value for a given moment with the set value and overdriving the processor outputs.
A method for supplying a cooling medium by means of a system for supplying a cooling medium to a heat exchanger of heat machines having j-th sections of the heat exchanger and comprising a compressor, a condenser, a divider and flow lines connecting the j-th sections of the heat exchanger, the compressor, the condenser and the divider with a supply distribution strip with supply flow lines of the j-th sections of the heat exchanger and a return strip connected to outflowing flow lines of the j-th sections of the heat exchanger, and a power supply and control system, characterised in that in each supply flow line of the j-th section or the outflowing flow line of the j-th section is mounted an input controlled shut-off valve or an output controlled shut-off valve being in communication with a control system receiving electrical signals from the temperature sensors, one of each located at an output of the outflowing flow line of the j-th section assigned to it, on a basis of which the instantaneous temperature t_ij of the cooling medium at the output of each outflowing flow line of the j-th section is determined, and then, based on the measured temperatures t_ij of the cooling medium at the output of each outflowing flow line of the j-th section, the average temperature t_{avg j} of the j-th section and the distribution of the difference average temperatures t_{avg j} at the output of the outflowing flow lines of the j-th sections of the cooling medium are determined, and in the case when the temperature t_{avg j} at the output of the outflowing flow line of the j-th section is less than or equal to the set temperature t_sp, a j-th coil of the controlled shut-off valve is disconnected from the power supply, otherwise to the j-th coil of the controlled shut-off valve power is supplied so that the cooling medium is supplied to the j-th section of the heat exchanger of the heat machine.
The invention finds particular application in inverter machines operating in large power ranges. The newly developed solution uses electronically controlled solenoid valves that automatically supply individual sections depending on the demand at a given point of operation of the device. The introduction of the invention gives the possibility of better use of energy to power the device and improvement of its efficiency parameters, for example SCOP or SEER, depending on the intended use.
The use of the medium distribution method according to the invention results in that the cooling medium is evenly distributed throughout the entire volume of the exchanger which reduces the problem of excessive and accelerated overicing of the exchanger. Modulating the flow of the cooling medium in individual sections of the exchanger enables effective use of the heat machine with lower electricity consumption.
The subject matter of the invention is shown in embodiments in drawings, where Fig. 1 shows a heat machine equipped with a cooling medium supply system supplying the cooling medium to a heat exchanger of heat machines in the simplest version, Figs. 2, 3, 4, 5, 6 and 7 show the heat machine equipped with other cooling medium supply systems supplying the cooling medium to the heat exchanger of heat machines, Fig. 8 shows the heat machine equipped with a cooling medium supply system supplying the cooling medium to the heat exchanger of heat machines in yet another embodiment, Fig. 9 shows an exemplary distribution histogram of instantaneous temperatures, Fig. 10 shows an example sequence of operation of individual shut-off valves controlled by signals from a control system, Fig. 11 shows a waveform of control signals proportional to an offset sent by the control system to solenoid valves with a servo-control, Fig. 12 shows schematically a power supply and control system of the heat machine in one of the embodiments, Fig. 13 schematically shows the power supply and control system of the heat machine in one of the other embodiments, Fig. 14 shows an embodiment of a solenoid throttling and an expansion valve, Fig. 15 shows an exemplary characteristic of a digital control signal S and a volumetric flow rate Q of the throttling valve and the expansion valve versus time, Fig. 16 shows an example of a shut-off valve, Fig. 17 shows an exemplary characteristic of the pulse digital control signal S and the volumetric flow rate of the shut-off valve versus time, Fig. 18 shows exemplary temperature assemblies of set having temperature sensors, Fig. 19 shows sections of outflowing flow lines in which the cooling medium has completely evaporated, Fig. 20 shows graphs of temperatures inside the outflowing flow lines in which the cooling medium has completely evaporated, Fig. 21 shows graphs of temperatures inside outflowing flow lines in which the cooling medium has partially evaporated, Fig. 22 shows sections of outflowing flow lines in which the cooling medium has partially evaporated, Fig. 23 shows two exemplary optical assemblies, Fig. 24 shows sections of outflowing flow lines in which the cooling medium has completely evaporated, Fig. 25 shows a graph of radiation intensity measured by a measuring element in outflowing flow lines in which the cooling medium has completely evaporated, Fig. 26 shows a graph of radiation intensity measured by a measuring element in the outflowing flow lines in which the cooling medium has partially evaporated, Fig. 27 shows sections of outflowing flow lines where the cooling medium has partially evaporated, Fig. 28 shows exemplary ultrasonic assemblies comprising ultrasonic probes, Fig. 29 shows section of the outflowing flow lines where the cooling medium has completely evaporated, Fig. 30 shows a graph of signal intensity read by a measuring probe in the outflowing flow lines in which the cooling medium has completely evaporated, Fig. 31 shows a graph of signal intensity read by the measuring probe in the outflowing flow lines in which the cooling medium has partially evaporated, Fig. 32 shows a section of outflowing flow lines in which the cooling medium has partially evaporated, Fig. 33 shows a schematic diagram of the power supply and control system of the heat machine, Figs. 34 and 35 show a block diagram of control algorithm of the cooling medium supply system supplying the cooling medium to the heat exchanger of heat machines.
Fig. 1 shows a heat machine 5 equipped with a cooling medium supply system 1 supplying the cooling medium to the heat exchanger 10 of heat machines in the simplest version, in particular with a system for multi-section cooling medium injection supplying the cooling medium into a lamellar exchanger of heat machines. The cooling medium supply system 1 shown in Fig. 1 comprises j-th sections where j = 11, 12, 13, 14.... n, a heat exchanger 10 which has a compressor 4, a condenser 7 and a divider 6 having a supply manifold 8 with supply flow lines 21, 22, 23, 24 of the j- th sections 11, 12, 13, 14 and a return strip 9 connected to outflowing flow lines 26, 27, 28, 29 of the j- th sections 11, 12, 13, 14 of the heat exchanger 10 as well as a control system 50. In an embodiment shown in Fig. 1, the cooling medium supply system 1 further comprises a set 40 of controllable input shut-off valves 41, 42, 43, 44, one of each located in its associated delivery flow line 21, 22, 23, 24 of the j- th section 11, 12, 13, 14. The control system 50 of the cooling medium supply system 1 of Fig. 1 communicates with controlled inlet shut-off valves 41, 42, 43, 44 and with a set 30 of temperature sensors 31, 32, 33, 34, one of each located in its outflowing flow line nearby an outlet of the associated outflowing flow line 26, 27, 28, 29 of the j- th section 11, 12, 13, 14 of the heat exchanger 10 to determine the distribution of the temperature difference at the outlets of the outflowing flow lines 26, 27, 28, 29 of the j- th sections 11, 12, 13, 14 of the heat exchanger 10 for controlling the controlled input shut-off valves 41, 42, 43, 44. The heat exchanger 10 is cooled by air or a mixture of gases which is forced around the section by means of a fan 59.
The flow of the cooling medium in the heat machine 10 shown in Fig. 1 as well as in the heat machines shown in Figs. 2, 3, 4, 5, 6, 7 is forced by the compressor 4 which pumps the cooling medium to the condenser 7, after which the cooling medium flows to the supply manifold 8 and then to the controllable shut-off valves 41, 42, 43, 44 of the controllable j-th sections, respectively 11, 12, 13, 14 of the heat exchanger 10. Fig. 1 shows an embodiment of lamellar or plate fin heat exchanger with seven section injectors, however, there can be any number of section injectors. The solution can be used in other types of exchangers, for example micro-channel, tubular or combinations thereof, with any number of electronically controlled sections of cooling medium injectors. A parameter limiting the number of controlled sections can be only the number of inputs and outputs of controlling system 50. Controlling can be carried out by means of solenoid valves equipped with a coil assuming an on/off state or solenoid valves with servo-control which open the flow proportionally to a sent or given control signal or by other similar type actuator. The controlling system 50 with a driver controller 70 shown in Fig. 33, for example a PLC or an electronic control module, performs automated switching on or off of solenoid valve coils or controlled input shut-off valves 41, 42, 43, 44, taking as a feedback signal measured temperature values indicated by the sensors 31, 32, 33, 34 of the j- th sections 11, 12, 13, 14 of the heat exchanger 10, respectively. In one embodiment of the module, a programmable logic controller (Programmable Logic Controller, in short PLC), for example PLC Beckhoff CX 9020 from Beckhoff, Germany which is a universal microprocessor by means of which it is possible to control the operation of machines and/or processing and/or operational processes.
Optionally, in parallel with the temperature sensors, cooling medium flow sensors mounted on each of the exchanger sections, as well as units for determining the ratio of cooling medium evaporation, can cooperate. Temperature sensors measure the distribution of the temperature difference and/or the ratio of evaporation of the cooling medium at the outlets of the cooling medium from the heat exchanger and then these data in the form of an electronic signal are interpreted by the control system 50. The control unit, processing the measurement data from the feedback control loop, sends converted signals to the appropriate inputs of solenoid valves or controlled input shut-off valves 41, 42, 43, 44, in particular controlled input expansion valves, minimizing the deviation of the temperature gradient and/or optionally temperature and flow in the entire volume of the heat exchanger. The temperature difference between the input and the output of the j- th section 11, 12, 13, 14 of the heat exchanger 10 is of great importance for the Coefficient of Performance (COP) of the heat machines. This parameter is particularly important for heat machines such as heat pumps, as it determines the ratio of the amount of heat supplied to the amount of energy consumed by the pump. For long periods of operating under changing conditions, the benefits of the newly developed cooling control and distribution method have a significant impact on energy consumption.
Figs. 2, 3 and 4 show other embodiments of the cooling medium supply system supplying the cooling medium to the heat exchanger 10 of heat machines. Thus, Figs. 2 and 3 show the systems 101, 201 of supplying the cooling medium to the heat exchanger 10 of the heat machine 105, 205, using the same system of multi-section injection of the cooling medium to the heat machine exchanger as in Fig. 1, differing only in the number of temperature sensors. The embodiment shown in Fig. 2 has zone sensors 35, 36, 37 of the set 130 and the embodiment shown in Fig. 3 has zone sensors 38, 39 of the set 230 that measure the zone temperature in areas containing more than one heat exchanger section.
In turn the embodiment presented in Fig. 4 which is similar to the embodiment shown in Fig. 1 differs in that apart from the temperature sensors 31, 32, 33, 34 of the set 330 on the outflowing flow lines 26, 27, 28, 29 of the heat exchanger 10 of the heat engine 305, the system 301 comprises electronic flow sensors 61, 62, 63, 64 of the cooling medium of the set 360 of electronic sensors 61, 62, 63, 64 of cooling medium flow for each of the j- th sections 11, 12, 13, 14, by means of which a liquid flow measurement is further made for each of the j- th sections 11, 12, 13, 14, respectively. The flow values at the outlet of each j- th section 11, 12, 13, 14 of the heat exchanger 10 are received as an additional parameter of the feedback loop by the control system 50. The non-uniformity of the flow and temperature distribution is measured in real time and the task of the control system is to minimize deviation of these two quantities in a short control time.
The embodiment shown in Fig. 5 has a cooling medium supply system 401 which, instead of a set 40 of controllable input shut-off valves 41, 42, 43, 44, one of each in the associated supply flow line 21, 22, 23, 24 of the j- th section 11, 12, 13, 14, has an output set 440 of controlled output shut-off valves 46, 47, 48, 49, one of each located in its associated outflowing flow line 26, 27, 28, 29 of the j- th section 11, 12, 13 14. In this embodiment, the control system 50 of the cooling medium supply system 401 communicates with the controlled output shut-off valves 46, 47, 48, 48 and a set 30 of temperature sensors 31, 32, 33, 34, one of each located near the outlet of its associated outflowing flow lines 26, 27, 28, 29 of the j- th section 11, 12, 13, 14 of the heat exchanger 10 of the heat machine 405, to determine the distribution of the temperature difference at the outlets of the flow lines 26, 27, 28, 29 of the j- th section 11, 12, 13, 14 of the heat exchanger 10 for controlling the controlled output shut-off valves 46, 47, 48, 49.
Figs. 6 and 7 show cooling medium supply systems 501, 601. These are examples of using the invention in other types of exchangers, for example microtube 510 and microchannel 610, the other components of which are the same as in the embodiment of the cooling medium supply system of the heat exchanger 10 of the heat machine shown in Fig. 1.
Fig. 8 shows the heat machine 5 equipped with a cooling medium supply system 701 for supplying the cooling medium to the heat exchanger 10 of the heat machines, in particular a system for multi-section injection of a cooling medium into the plate fin heat exchanger of the heat machines. The cooling medium supply system 701 of Fig. 8 has j-th sections, where j = 11, 12, 13, 14.... n, the heat exchanger 10 which comprises the compressor 4, the condenser 7 and the divider 6 having the supply distribution strip 8 with supply flow lines 21, 22, 23, 24 of the j- th sections 11, 12, 13, 14 and the return strip 9 connected to the outflowing flow lines 26, 27, 28, 29 of the j- th sections 11, 12, 13, 14 of the heat exchanger 10 as well as the control system 50. In the embodiment shown in Fig. 8, the cooling medium supply system 701 further comprises a set 40 of controlled input throttling or input valves shut-off valves 41, 42, 43, 44, and in particular controllable input expansion valves, one of each located in its associated supply flow line 21, 22, 23, 24 of the j- th section 11, 12, 13, 14. The control system 50 of the cooling medium supply system 701 of Fig. 8 communicates with the controlled input shut-off valves 41, 42, 43, 44, in particular the controlled input expansion valves, and with a set 30 of temperature sensors 31, 32, 33, 34, one of each located nearby the outlet of its associated outflowing flow lines 26, 27, 28, 29 of the j- th section 11, 12, 13, 14 of the heat exchanger 10, and/or the set of 60 flow sensors shown in Fig. 33, and/or the set of 80, 180, 280 assemblies 81, 82, 83 and 84; 181, 182, 183 and 184; 281, 282, 283 and 284 for determining the ratio of evaporation of the cooling medium in order to determine the distribution of the temperature difference at the outlets of the outflowing flow lines 26, 27, 28, 29 of the j- th sections 11, 12, 13, 14 of the heat exchanger 10 for the purpose of controlling the controlled inputs shut-off valves 41, 42, 43, 44, in particular controlled input expansion valves. The heat exchanger 10 located in the cooling area shown schematically in Figs. 12 and 13 is cooled by air or a mixture of gases, the flow of which around the section is forced by the fan 59.
The flow of the cooling medium in the heat machine with a plate fin exchanger 10 of Fig. 8, as well as in heat machines with exchangers of another type, for example with a tubular exchanger, microchannel exchanger, is forced by the compressor 4 which pumps the cooling medium to the condenser 7 and then the cooling medium flows to the supply distribution strip 8 and then enters the controlled input shut-off valves 41, 42, 43, 44, in particular the controlled input expansion valves of the j-th sections, respectively 11, 12, 13, 14, of the heat exchanger 10. Fig. 8 shows an embodiment for a plate fin exchanger with seven injector sections, however there can be any number of injector sections. The solution can be used in other types of exchangers, for example microchannel, tubular or combinations thereof, with any number of electronically controlled sections of cooling medium injectors. The parameter limiting the number of controlled sections can only be the number of inputs and outputs of the control system 50. The control can be carried out by means of solenoid valves equipped with a coil accepting the on/off state or solenoid valves with servo-control and/or expansion valves that open the flow proportionally to the given control signal and/or by means of other similar type of actuator. The control system 50 with the programmed controller 70 shown in Fig. 33, for example a PLC or electronic control module, performs the automated turning on or turning off solenoid coils or controlled input shut-off valves 41, 42, 43, 44, in particular controlled input expansion valves, taking as a feedback signal of the measured temperature value indicated by the temperature sensors 31, 32, 33, 34 of the j- th sections 11, 12, 13, 14, respectively, or taking as a feedback signal the ratio of evaporation of the cooling medium at the outlets of the outflowing flow lines 26, 27, 28, 29 of the sections 11, 12, 13, 14 of the heat exchanger 10. In one of the embodiments, a programmable logic controller (PLC) was used, for example PLC Beckhoff CX 9020 from Beckhoff, Germany which is a universal microprocessor device by means of which it is possible to control the operation of machines or technological processes.
Fig. 9 shows an exemplary course of the histogram of the distribution of instantaneous temperatures shown in the form of bars and the average temperature shown as a dotted line on individual sections of the exchanger for different values of the cooling medium flow, observed at various points of the heat machine operation. A graph 711 shows the distribution of instantaneous and average temperatures for the heat machine equipped with a traditional cooling medium manifold. Significant deviations of the instantaneous temperatures from the set temperature for each section of the exchanger are visible. These changes can be both below or above the preset heat exchanger operating temperature. A graph 712 shows the distribution of the instantaneous temperatures shown in Fig. 9 in the form of bars and the average temperature shown in Fig. 9 with a dashed line for the heat exchanger section of the heat machine equipped with active multi-section cooling medium injection. A significant change compared to the graph 711 is the much smaller deviation of all values from the set value t_sp. Temperature stabilization in the evaporator volume is important not only from the point of view of cooling but also to ensure maximum efficiency of the heat engine.
Fig. 10 shows an exemplary sequence of operation of individual shut-off valves controlled by signals generated by the control system 50. In the waveform 713 of time shifts and differences in the switching times of shut-off valves assuming the on/off state are visible. Fig. 11 shows an analogous course of controlling the shut-off valves as in Fig. 10, except that Fig. 11 shows the waveform 714 of the control signals proportional to the error sent by the control system to the servo-operated solenoid valves. Fig. 10 shows the waveform 713 of the signals controlling individual shut-off valves of the heat exchanger section of the heat machine in the on/off state.
Fig. 12 shows schematically the power supply and control system 2 of the heat machine 5 with the control system 50, components such as the temperature sensor 52 of the cooling space 3, the temperature controller 53 of the cooling space 3 which have been described above and the cooling medium supply system supplying the cooling medium to the heat exchanger. The reference numerals referring to the described elements and arrangements of the previous figures are the same as those given in Fig. 12.
Fig. 13 shows schematically the power supply and control system of heat machine 2, shown in Fig. 8, with control system 50 and controller 70 as well as components such as temperature sensor 52 of the cooling space, the cooling space temperature controller 53, which have been described above, which are components of cooling medium supply system 701 supplying the cooling medium to the heat exchanger, shown in Fig. 8. The reference numerals referring to the described elements and arrangements of the previous figures are the same as those given in Fig. 13. The set 80, 180, 280 of assemblies 81, 82, 83 and 84; 181, 182, 183 and 184; 281, 282, 283 and 284 for determining the ratio of evaporation of the cooling medium in one embodiment where, in addition to the set 80, 180, 280, the cooling medium supply system 701 comprises a set of 30 temperature sensors 31, 32, 33, 34, one of each situated nearby the outlet of its associated outflowing flow line 26, 27, 28, 29, the temperature sensors 31, 32, 33, 34 may be one of the three sensors of the set 80, 180, 280 of the units 81, 82, 83 and 84; 181, 182, 183 and 184; 281, 282, 283 and 284 for determining the ratio of evaporation of the cooling medium shown in Figs. 18, 23 and 28.
Fig. 14 shows an embodiment of an electronic throttling and expansion valve which in its body 900 has a built-in inlet port 901 and an outlet port 902. The chamber 903 of the inlet side is separated by the valve seat 905 from the outlet chamber 904. Throttling of the flow of the medium in an adjustable and proportional manner takes place by rotation of the shaft 906 of a stepper motor 907, for example a bipolar one. The output shaft of the motor is connected to the spindle 908 which, through the thread cut on it and connection with the guide nut 909, causes the valve seat to move linearly along the axis of rotation of the spindle 908. The value of the seat displacement is proportional to the set ratio of opening/flow rate of the cooling medium. The rotational movement of the stepper motor is carried out by an appropriate sequence of signals on the outputs 74 of the module for switching on/off the throttling or expansion valves 78. Fig. 15 shows an exemplary characteristic of the digital control signal S and the volumetric flow rate Q as a function of time. Both of these quantities are correlated with each other in time.
In turn Fig. 16 shows an embodiment of a shut-off valve which, similarly to the electronic expansion valve, has an inlet port 1001 and an outlet port 1002 built into its body 1000. The shut-off valve is equipped with a coil 1003 which, when connected to a power source, causes the sliding motion of the piston 1004 together with the pivot 1005, resulting in connection of the flow between the inlet side chamber 1006 and the outlet side chamber 1007. Such a valve is controlled by a sequence of appropriate on/off impulse signals on the outputs 74 generated by the module 78 for switching on/off the shut-off, throttling or expansion valves. Fig. 17 shows an exemplary characteristic of the pulsed digital signal S of the control of the shut-off valve and the volumetric flow rate of the medium. As in the case of using electronic expansion valves, both of these quantities are correlated with each other in time.
Fig. 18 shows two temperature units 81, 82 of the set 80 comprising at least two or three temperature sensors 86, 87, 88 located in a row along each of the cooling medium outflowing flow lines 26, 27 of the j- th sections 11, 12. The cooling medium from the supply distribution strip 8 enters, in the embodiment shown in Fig. 18, the controlled input expansion valves 41, 42 of the j- th sections 11, 12 through which it flows to the evaporator where it evaporates and changes its state of aggregation to volatile/gas.
Fig. 19 shows the fragments I₁, I₂ of the outflowing flow lines 26, 27, 28, 29 in which the cooling medium has evaporated and shows the homogeneity of the gaseous cooling medium inside the outflowing flow lines 26, 27, 28, 29, the temperature T₁, T₂ of which in both sections is the same as shown in Fig. 20. In turn, Fig. 22 shows fragments I₁, I₂ of the outflowing flow lines 26, 27, 28, 29, where the cooling medium has completely evaporated only in section I₂, while in section I₁ located closer to the return strip 9, the cooling medium has partially evaporated, therefore the temperature T₁ is lower than the temperature T₂ in section I₂, which is shown in Fig. 21. Information about the temperature difference at the outlets of outflowing flow lines 26, 27, 28, 29 of j-th sections of the heat exchanger sections is used to control the controlled input throttling valves or the controlled input shut-off valves 41, 42, in particular the controlled input expansion valves, to reduce the amount of cooling medium supplied to the section where there is no homogeneity of the gaseous cooling medium inside the outflowing flow lines 26, 27, 28, 29.
Figs. 23, 24, 27 show two exemplary optical units 181, 182 of the set 180 located on fragments of the outflowing flow lines, in which there are fragments transparent to electromagnetic radiation, for example in the visible light range, equipped with electromagnetic measuring assemblies 181, 182, for example optical measuring units, for determining the ratio of evaporation of the cooling medium. A single measurement unit 181, 182 for a given section comprises an electromagnetic radiation emitter 188, for example in the visible light range, such as LEDs, an electromagnetic radiation measuring element 186, for example in the visible light range, and an electromagnetic radiation transparent section or fragment 187, for example in the light range with sight glasses 185, built into the outflowing flow line 26, 27, 28, 29 of the j- th sections 11, 12 and transmitting a beam 189 of electromagnetic radiation emitted by the emitter 188 located at the wall of the transparent fragment 187 and received by the measuring element 186 located opposite the emitter 188 and measuring the change in the parameters of the electromagnetic radiation beam 1189 after passing across the transparent section through the measurement area of the transparent fragment 187 located, for example, between the sight glasses 185 in the case of visible light.
As the measuring element 186 of the distorted electromagnetic radiation beam, a photoresistor may be used in a range of visible light. In the case of visible light, the sight glasses 185 are placed along a line perpendicular to the longitudinal axis of the outflowing flow lines, so that the electromagnetic radiation beam emitted by the emitter 188, after distortion, reaches the measuring element 186 as the electromagnetic radiation beam 1189, located in the electromagnetic radiation measurement area, for example a photoresistor. The essence of the invention is that the electromagnetic radiation beam should be perpendicular to the horizontal plane of the transparent fragment. Such location provides analysis of the state of aggregation and homogeneity of the cooling medium inside the outflowing flow lines. As shown in Fig. 24, with the correct dosing of the medium, the cooling medium flowing through the sight glass area is homogeneous, being in a gaseous state throughout the cross-section. With too much cooling medium dosing, for example shown in Fig. 27, a liquid state 1187 appears between the sight glasses 185 which, due to the force of gravity, fills the space at the bottom of the transparent fragment 187. The level of the liquid phase is proportional to the excess of the supplied cooling medium. The electromagnetic radiation beam emitted by the emitter, in the case shown in Fig. 27, on the side of the measuring receiver has parameters different from those of the steady and assumed fully gaseous state. In this case, the measuring element 186 receives a signal which is a distorted signal with a lower irradiance E₁ as shown in Fig. 26 as compared to a correct signal with a higher irradiance E₁ as shown in Fig. 25. Measuring elements located in each of the exchanger sections give feedback to the control system which is interpreted as feedback to the control system in real time and affects the control status of the relevant valves of the heat exchanger section. This solution is an improvement of the solution based on temperature measurement, mainly due to the lower inertia of the automation system. Electromagnetic radiation sensors detect changes almost immediately, unlike temperature sensors, for which the change in the value of the measured physical quantity depends on the ambient temperature and the heat capacity of the material of which the exchanger and sensor are made. This advantage has a positive effect on the quality of the control system operation which is closely correlated with the efficiency and effectiveness of the heat machine.
Referring to Figs. 28, 29 and 32, two ultrasonic units 281, 282 of the set 280 are shown on fragments of the outflowing flow lines in which the ultrasonic probes 286, 288 have been placed. These probes are mounted in a number of two or more at each end of a particular sections of the outgoing lines at the surfaces tangential to the surface forming the outgoing line conduit. The transmitting probe 286 located on the side of each j- th section 11, 12 of the exchanger performs the function of transmitting ultrasonic waves, while the receiving probe 288 performs the function of the signal receiver. The use of such embodiment, in contrast to the optical solution, does not require any special mechanical modification in the flow line installation and can be used as a hardware development of the system which at the time of production was not intended for the implementation of the invention. The appearance of heterogeneity of the medium inside the outflowing flow line applies changes in the signal read by the receiving probes which are communicated with the system controlling a control state of the valves of individual sections of the heat exchanger. Fig. 29 shows an example in which a cooling medium which is homogeneous throughout the cross-section and flows through the flow line being in the gaseous state. The ultrasonic wave signal 285 and 287 shown in Fig. 29 emitted by the transmitting probe 286 in this state is implemented in the control module as a steady state that the control system tends to maintain. Fig. 32 shows the same section of the installation as Fig. 29, except that Fig. 32 shows a fragment of the cross-section with the liquid state 289 of cooling medium. In this case, the receiving probe 288 receives a signal which is a distorted signal with a lower energy value E₁ which was shown in Fig. 31, compared to the correct signal with higher energy E₁ which is shown in Fig. 30.
Fig. 33 illustrates architecture of a cooling medium flow control system 50 that comprises a controller 70, for example a PLC, the main component being a processor 75, for example a 32-bit processor with a user program that interprets the analog or digital inputs 73 to which a temperature sensors set 30 and/or a flow meters set 60 is connected. The processor 75 comprises a temperature/flow average value calculation module 76 and a value comparison module 77 of an average temperature/flow with set values which is accomplished by a userdefined algorithm that in the data region processes immediate temperature/flow signals, also known as discrete signals, measured over a specific sampling time. Based on the analysis of the immediate temperature/flow signals stored in the memory 71 of the processor 75, an average temperature/flow value is calculated over a predetermined time period. In addition, the processor 75 may optionally have a module 79 for determining the ratio of evaporation of the cooling medium and a module 78 for switching on/off the shut-off or throttling valves which compares the current mean value determined at a given moment with the set value and, based on the comparison, at specified intervals, overrides the outputs 74 to which solenoid valves of a set 40 of shut-off solenoid valves are connected, assuming an on/off state or a state proportional to the value of the measured error, for example PWM type, in the case of solenoid valves with servo control.
Basing on Fig. 12 and Fig. 13, it is possible to present a method of supplying a cooling medium which is carried out by means of a cooling medium supply system to the heat exchanger 10, 510, 610 of heat machines which comprises the compressor 4, the condenser 7, the divider 6 and the flow lines connecting j- th sections 11, 12, 13, 14 of heat exchanger 10, the compressor 4, the condenser 7 and the divider 6 with the supply distribution strip 8 with the supply flow lines 21, 22, 23, 24 of the j- th sections 11, 12, 13, 14 and the return strip 9 connected to the outflowing flow lines 26, 27, 28, 29 of the j- th sections 11, 12, 13, 14 of the heat exchanger 10, and the power supply and control system 2. In general, the method which is the subject of the invention is based on that in each inlet flow line 21, 22, 23, 24 of the j-th section 11, 12, 13, 14 or outflowing flow line 26, 27, 28, 29 of the j-th section 11, 12, 13, 14 is mounted the inlet controlled shut-off valve or an inlet controlled throttle valve or the inlet controlled expansion valve 41, 42, 43, 44 of the set 40 or the outlet controlled shut-off valve 46, 47, 48, 49 communicating with the control system 50 receiving from the temperature sensors 31, 32, 33, 34, one located near the outlet of the assigned outflowing flow line 26, 27, 28, 29 of the j-th section 11, 12, 13, 14, electrical signals on the basis of which the instantaneous temperature t_ij of the cooling medium at the outlet of each outflowing flow line 26, 27, 28, 29 of the j-th section 11, 12, 13, 14, is determined and then basing on the measured temperatures t_ij of the cooling medium at the outlet of each outgoing flow line 26, 27, 28, 29 of the j-th section 11, 12, 13, 14, the average temperature t_avgj of the j-th section and the distribution of the difference in average temperatures t_{avg j} at the outlets of the outflowing flow lines 26, 27, 28, 29 of the j-th section of the cooling medium are determined, and in the case when the temperature t_avgj at the outlet of the discharge flow line 26, 27, 28, 29 of the j-th section 11, 12, 13, 14 is less than or equal to the set temperature t_sp, the j-th coil of the controlled shut-off valve 41, 42, 43, 44 is disconnected from the power supply, otherwise, the j-th coil of the controlled shut-off valve or the input controlled throttling valve or the input controlled expansion valve 41, 42, 43, 44 of the set is energized so that the cooling medium is supplied to the j-th section 11, 12, 13, 14 of the heat exchanger 10 of the heat machine 5.
Referring to the previous figures, especially Figs. 12, 13 and 33, in Figs. 34 and 35 is shown a block diagram of algorithm for controlling the cooling medium supply system 1 supplying the cooling medium to the heat exchanger 10 of heat machines provided with the system of multi-section cooling medium injection into the heat exchanger of the heat machine, according to which, after the start in step 800, in step 801 instantaneous temperature values of the cooling medium of the j-th section, t_ij, are measured, on the basis of which the average temperature t_avg of the j-th section is calculated and the set temperature t_spj is assumed. In the next step 802 the deviation of the average temperature value at the outlet of the j-th section of the heat exchanger from the set temperature value is calculated, and then in step 803 a decision step is performed in which if the average temperature t_avg of the j-th section is less than or equal to at a set temperature t_spj, the solenoid coil of the j-th section is turned off in step 804 and no cooling medium flows through the j-th section. Otherwise, the coil is switched on and the cooling medium is supplied to the appropriate heat exchanger section of the heat machine.
Optionally, in an embodiment presented in Fig. 34, parallelly with the temperature measurement in step 805, the instantaneous value of the flow stream of the j-th section Q_ij can be measured, the average value of the flow stream of the j-th section Q_{avg j} is calculated and the set value of the flow rate Q_spj is assumed. Similarly as in the case of temperature reading, in step 806 the average flow value for a given section of the exchanger is compared with the set value, followed by a decision in step 807, in which, if the average value of the j-th section flow rate is less than or equal to set point, in step 808 the coil of a given section is switched on and cooling medium is supplied to a given section of the heat exchanger. In the next step 809, there is a time delay that eliminates disturbances in the slow-changing heating or cooling process.
If further control of the valves of individual sections of the heat exchanger is required, in order to achieve high efficiency and effectiveness of the heat machine operation, in step 810 it is checked whether the cooling medium has fully evaporated, both in the case of temperature reading and in the case of measuring the instantaneous value of the flow stream of the j-th section, and if it is found that the cooling medium has fully evaporated, the coil of the inlet controlled shut-off valve and/or the inlet controlled throttling valve and/or the inlet controlled expansion valve of given section is switched on and the cooling medium is supplied to the given section of the heat exchanger. On the other hand, if it is determined that the cooling medium has not fully evaporated, the coils of the inlet controlled shutoff valve and/or the inlet controlled throttling valve and/or the inlet controlled expansion valve are disconnected from the power supply and the cooling medium is not supplied to the heat exchanger section.

List of references

1, 101, 201, 301, 401, 501, 601, 701 System for supplying cooling medium
2 Power supply and control system
3 Cooling space
4 Compressor
5, 105, 205, 305, 405 Heat machine
6 Divider
7 Condenser
8 Supply distribution strip
9 Return strip
10, 510, 610 Heat exchanger
11, 12, 13, 14 Section
21, 22, 23, 24 Supply flow line
26, 27, 28, 29 Outlet flow line
30, 130, 230 Set of temperature sensors
31, 32, 33, 34 Temperature sensors
35, 36, 37, 38, 39 Zone sensors
40 Set of controllable input shut-off valves
41, 42, 43, 44 Controllable input shut-off valves
46, 47, 48, 49 Controllable output shut-off valves
50 Control system
52 Temperature sensor
53 Temperature controller
59 Fan
60 Flow meter set or set of electronic meters of cooling medium
61, 62, 63, 64 Electronic meters of cooling medium
70 Controller
71 Processor memory
73 Analog input or digital input
74 Output
75 Processor
76 Temperature/flow average value calculation module
77 Value comparison module of average temperature/flow with set values
78 Module of switching on/off shut-off and/or throttling and/or expansion valves
79 Module of determining ratio of evaporation of cooling medium
80, 180, 280 Set of units of determining ratio of evaporation of cooling medium
81, 82, 83 and 84; 181, 182, 183 and 184; 281, 282, 283 and 284 Units of determining ratio of evaporation of cooling medium
86, 87, 88 Temperature sensor
185 Sight glass
186 Electromagnetic radiation measuring element
187 Transparent fragment for electromagnetic radiation
188 Emitter
285, 287 Ultrasonic wave signal
286 Transmitting probe
288 Receiving probe
289, 1187 Liquid state
330 Set of temperature sensors
360 Set of electronic sensors of cooling medium flow
440 Output set of controlled output shut-off valves
711, 712 Graph of temperature distribution
713, 714 Waveform
800 Starting step
801 Step of measurement of instantaneous temperature values of cooling medium
802 Step of calculation of deviation of average temperature value
803 Step of decision
804 Step of turning off of solenoid coil of j-th section
805 Step of measurement of instantaneous values of flow stream of j-th section
806 Step of comparison of average flow value for given section
807 Step of decision
808 Step of turn on/turn off of coil of electric valve
809 Step of time delay
810 Checking step whether cooling medium has been fully evaporated
900, 1000 Body
901, 1001 Inlet port
902, 1002 Outlet port
903, 1006 Chamber of inlet side
904, 1007 Chamber of outlet side
905 Valve seat
906 Shaft of stepper motor
907 Stepper motor
908 Rotating spindle
909 Guide nut
1003 Coil
1004 Piston
1189 Electromagnetic radiation beam

Claims

A system (1) for supplying cooling medium to a heat exchanger (10, 510, 610) of a heat machine (5) with j-th sections (11, 12, 13, 14) of the heat exchanger (10) and comprising
a compressor (4),

a condenser (7),

flow lines connecting the j-th sections (11, 12, 13, 14) of the heat exchanger (10) with the compressor (4) and a divider (6) having
a supply distribution strip (8) with supply flow lines (21, 22, 23, 24) of the j-th sections (11, 12, 13, 14),

a return strip (9) with outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the heat exchanger (10), and

a power supply and control system (2),

characterised in that the system (1) for supplying cooling medium to the heat exchanger (10, 510, 610) further comprises a set (40) of controlled input shut-off valves and/or controlled input throttling valves, and/or controlled input expansion valves (41, 42, 43, 44), one of each in the assigned supply flow line (21, 22, 23, 24) of the j-th section (11, 12, 13, 14) of the heat exchanger (10) or a set of controlled output cut-off valves (46, 47, 48, 49), one of each located in the assigned outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) of the heat exchanger (10), whereas the power and control system (2) has a control system (50) with a controller (70) communicating with the controlled input shut-off valves and/or the controlled input throttling valves and/or the controlled input expansion valves (41, 42, 43, 44) or the controlled output shut-off valves (46, 47, 48, 49) as well as a set (30) of temperature sensors (31, 32, 33, 34), one of each located at an output of the assigned outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) communicating with the controller (70) and receiving distribution of temperature difference at the output of the outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the cooling medium for the purpose of controlling the controlled input shut-off valves and/or the controlled input throttle valves, and/or the controlled input expansion valves (41, 42, 43, 44) or controlled output shut-off valves (46, 47, 48, 49).
The system (1) according to claim 1, characterised in that the heat exchanger is a lamellar exchanger (10).
The system (1) according to claim 1, characterised in that the heat exchanger is a tubular exchanger (510).
The system (1) according to claim 1, characterised in that the heat exchanger is a microchannel heat exchanger (610).
The system (1) according to claim 1, characterised in that the controller (70) is a programmable logic controller (PLC).
The system (1) according to claim 5, characterised in that the PLC controller comprises a processor (55) with a user program interpreting a status of analog or digital inputs (73) of the processor and stored in a memory (71) of the processor, a temperature/flow average value calculation module (76), a value comparison module (77) of an average temperature/flow with set values, a module (78) of switching on/off of shut-off or throttling valves comparing the determined temperature/flow current average value for a given moment with the set temperature/flow value and overdriving the processor outputs (74).
The system (1) according to one of claims 1 to 6, characterised in that the system (1) for supplying cooling medium to the heat exchanger (10) of the heat machine (5) further comprises a set (80) of units (81, 82, 83, 84) determining the ratio of evaporation of the cooling medium, at least one located on the outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the cooling medium and chosen from a group of a temperature unit, an optical unit and an ultrasonic unit, wherein the set (80) of the units (81, 82, 83, 84) for determining the ratio of evaporation of the cooling medium communicates with the controller (70) communicating with the controlled input shut-off valves and/or the controlled input throttling valves and/or the controlled input expansion valves (41, 42, 43, 44) or the controlled output shut-off valves (46, 47, 48, 49) for the purpose of controlling the controlled input shut-off valves and/or the controlled input throttling valves and/or the controlled input expansion valves (41, 42, 43, 44) or the controlled output shut-off valves (46, 47, 48, 49) for adjustment in time an amount of a cooling medium supplied to each j-th section (11, 12, 13, 14) of the heat exchanger (10).
The system (1) according to claim 7, characterised in that the units (81, 82, 83, 84) of the set (80) for determining the ratio of evaporation of the cooling medium are the units selected from the group comprising the temperature units, the optical units and the ultrasonic units or combinations thereof.
The system (1) according to claim 8, characterised in that the temperature unit (81) comprises at least three temperature sensors (86, 87, 88) located one behind the other along each of the outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the cooling medium.
The system (1) according to claim 8, characterised in that the optical unit (181) comprises an electromagnetic radiation emitter (188), an electromagnetic radiation measuring element (186) and a transparent fragment (187) for an electromagnetic radiation built-in the outflowing flow line (26, 27, 28, 29) of j-th sections (11, 12, 13, 14) of the cooling medium and transmitting through an electromagnetic radiation beam, preferably an optical signal emitted by the electromagnetic radiation emitter (188), located at a wall of the transparent fragment (187) for the electromagnetic radiation and received by the electromagnetic radiation measuring element (186), located opposite the emitter (188), and measuring the change in parameters of the electromagnetic radiation beam after penetrating across the transparent fragment through a measurement area of the electromagnetic radiation transparent fragment (187) located between transparent to electromagnetic radiation, preferably sight glasses (185).
The system (1) according to claim 8 or 10, characterised in that an optical unit (181) comprises an emitter, a measuring element and a transparent fragment built-in the outflowing flow line (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the cooling medium and transmitting through the light beam of the optical signal emitted by the emitter (188) located at the wall of the transparent fragment and received by the measuring element (186) located opposite the emitter (188) and measuring the light intensity of the light beam after penetrating along a diameter of the transparent fragment through the measurement area of the transparent fragment (187) located between the transparent sight glasses (185).
The system (1) according to claim 8, characterised in that an ultrasonic unit (282) comprises at least two ultrasonic probes (286) and (288) mounted on each outflowing flow line (26, 27, 28, 29) of j-th sections (11, 12, 13, 14) of the cooling medium at surfaces tangential to a surface forming the outflowing line duct, whereas the probe (286) located closer to the exchanger acts as a transmitter of ultrasonic waves and the probe (288) located closer to the return strip (9) acts as a receiver of ultrasonic waves.
A method for supplying a cooling medium by means of a system for supplying cooling medium to a heat exchanger (10, 510, 610) of heat machines (5) and defined in claim 1, having j-th sections (11, 12, 13, 14) of the heat exchanger (10), comprising a compressor (4), a condenser (7) and flow lines connecting the j-th sections (11, 12, 13, 14) of the heat exchanger (10) with the compressor (4) and a divider (6) with a supply distribution strip (8) with supply flow lines (21, 22, 23, 24) of the j-th sections (11, 12, 13, 14) and a return strip (9) connected to outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the heat exchanger (10), as well as the power supply and control system (2), characterised in that in each supply flow line (21, 22, 23, 24) of the j-th section (11, 12, 13, 14) or the outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) is mounted an input controlled shut-off valve and/or an input controlled throttle valve and/or an input controlled expansion valve (41, 42, 43, 44) or an output controlled shut-off valve (46, 47, 48, 49) being in communication with a control system (50) receiving electrical signals from the temperature sensors (31, 32, 33, 34), one of each located at an output of the outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) assigned to it, on a basis of which the instantaneous temperature t_ij of the cooling medium at the output of each outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) is determined, and then, based on the measured temperatures t_ij of the cooling medium at the output of each outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14), the average temperature t_{avg j} of the j-th section and the distribution of the difference average temperatures t_{avg j} at the output of the outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the cooling medium are determined, and in the case when the temperature t_{avg j} at the output of the outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) is less than or equal to the set temperature t_sp, a j-th coil of the controlled input shut-off valves and/or the controlled input throttling valves, and/or the controlled input expansion valves (41, 42, 43, 44), is disconnected from the power supply, otherwise to the j-th coil of the controlled input shut-off valves and/or the controlled input throttling valves, and/or the controlled input expansion valves (41, 42, 43, 44) power is supplied, so that the cooling medium is supplied to the j-th section (11, 12, 13, 14) of the heat exchanger (10) of the heat machine (5).
The method for supplying the cooling medium according to claim 13 by means of the system for supplying cooling medium to a heat exchanger (10, 510, 610) of heat machines (5) defined in claim 7, having the j-th sections (11, 12, 13, 14) of the heat exchanger (10), comprising the compressor (4), the condenser (7) and the flow lines connecting the j-th sections (11, 12, 13, 14) of the heat exchanger (10) with the compressor (4) and the divider (6) with the supply distribution board (8) with the supply flow lines (21, 22, 23, 24) of the j-th sections (11, 12, 13, 14) and the return strip or slat (9) connected to the outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the heat exchanger (10), as well as the power supply and control system (2), characterised in that in each supply flow line (21, 22, 23, 24) of the j-th section (11, 12, 13, 14) the units (81, 82, 83, 84) for determining the ratio of evaporation of the cooling medium are mounted, at least one located on the outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the cooling medium and selected from a group of a temperature unit, an optical unit and an ultrasonic unit and communicating with the control system (50) receiving from the units (81, 82, 83, 84) for determining the ratio of evaporation of the cooling medium and/or temperature sensors (31, 32, 33, 34), located one at the exit/output of the outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) assigned to it, electrical signals, on a basis of which the instantaneous temperature t_ij of the cooling medium at the exit/output of each outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) and/or the ratio of evaporation of the cooling medium is determined, and then based on measured temperatures t_ij of the cooling medium at the exit/output of each outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14), the average temperature t_{avg j} of the j-th section and the distribution of the difference average temperatures t_{avg j} at the output of the outflowing flow lines (26, 27, 28, 29) of the j-th sections (11, 12, 13, 14) of the cooling medium are determined and in the case when the temperature t_{avg j} at the output of the outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) is less than or equal to the set temperature t_sp, the j-th coil of the controlled shut-off valve (41, 42, 43, 44) is disconnected from the power supply, otherwise to the j-th coil of the controlled shut-off valve (41, 42, 43, 44) power is supplied, thanks to which the cooling medium is supplied to the j-th section (11, 12, 13, 14) of the heat exchanger (10) of the heat machine (5) and/or on the basis of information received about the ratio of evaporation of the cooling medium in each outflowing flow line (26, 27, 28, 29) of the j-th section (11, 12, 13, 14) and in the case when it is found that the cooling medium fully evaporated the coil of the input controlled shut-off valve and/or the input controlled throttling valve and/or the input controlled expansion valve of a given section is switched on and the cooling medium is supplied to the given section of the heat exchanger, and in the case if it is found that the cooling medium has not fully evaporated, the coils of the inlet controlled shut-off valve and/or the inlet controlled throttling valve and/or the inlet controlled expansion valve of the section are disconnected from the power supply and cooling medium is not supplied to a given section of the heat exchanger.