WO2024002840A2

WO2024002840A2 - System comprising a refrigeration circuit, and control module for such a system

Info

Publication number: WO2024002840A2
Application number: PCT/EP2023/066887
Authority: WO
Original assignee: Glen Dimplex Deutschland Gmbh
Priority date: 2022-06-29
Filing date: 2023-06-21
Publication date: 2024-01-04
Also published as: WO2024002840A3

Abstract

The invention relates to a system (2), in particular a large-scale refrigeration system, comprising a refrigeration circuit (8) and a connection for a further circuit (4) connected to the refrigeration circuit during operation, wherein: the refrigeration circuit (8) has an evaporator (10), a variable-speed compressor (12), a capacitor (16), and a throttle element (14), and preferably also a variable-speed fan (18); furthermore, a variable-speed pump (24) is positioned for circulating a fluid conducted in the further circuit (4); and, furthermore, a control module (22) comprising power electronics is provided as a common structural unit which has frequency converters (38) for controlling the variable-speed components, namely a fan (18), a compressor (12), and a pump (24). Therefore, the control module (22) is an integrated unit which preferably contains all of the control elements for the system, meaning that a control cabinet is not required. In particular, the control module has a cooling plate through which a cooling fluid can flow.

Description

System with a refrigeration circuit and control module for such a system

The invention relates to a system, in particular a refrigeration system with a refrigeration circuit. The invention further relates to a control module for controlling the operation of such a system.

The system is specifically a system for commercial or industrial use; it is specifically designed as a refrigeration system. In principle, the system can also be a heat pump system.

The systems in focus here have a heating or cooling output of typically more than 10 kW, preferably more than 50 kW or even more than 100 kW and, for example, up to 1000 kW (refrigeration) output.

In such commercial and industrial systems, the focus is on high energy efficiency and ease of maintenance as well as low costs, especially assembly costs. Since such systems are often customer-specific systems, the manufacturer of such systems is also interested in simplifying the product range, so that as many applications as possible can be covered with a small number of different types.

With regard to the desired energy efficiency, the output of modern systems is regulated as required. Components such as compressors, pumps or fans with variable speeds are used for this purpose. To A frequency converter is required to control such variable-speed components. Due to their high performance, they typically also require cooling.

Such systems generally require a comparatively high amount of assembly work. Typically, the control takes place via an industrial control cabinet in which the required control components are snapped onto top-hat rails, for example. The individual components must be wired on site.

Based on this, the invention is based on the object of specifying such a system which enables energy-efficient operation while at the same time keeping costs low and with little assembly effort.

The object is achieved according to the invention by a system, in particular a previously described commercial or industrial refrigeration system, which has a refrigeration circuit and connections for a further circuit connected to it during operation and in the assembled state for a fluid carried therein. In the case of a refrigeration system, this is in particular a coolant circuit for cooling components, such as commercial or industrial system components, e.g. refrigerated counters, cold rooms, medical devices, etc., or is used to provide cold for industrial processes. The fluid is a coolant, also known as a coolant.

Alternatively, the system is a heat pump system to provide heat on the consumer side. The other circuit in this case is a heating circuit. The fluid is then a heating fluid such as heating water.

The system typically has a system housing and the further circuit can be connected to the connections on the system housing. Hydraulic components such as valves are typically already located within the system housing or pumps for circulating the fluid of the further circuit are integrated. When assembled, the additional circuit is an additional part of the system.

The refrigeration circuit has an evaporator with a variable-speed fan, a variable-speed compressor, a condenser and an expansion valve/throttle element. The system also has a variable-speed pump for pumping and circulating a fluid, in particular coolant, which is carried in the further circuit during operation. This pump is arranged inside the system housing. The variable-speed components, namely the fan, compressor and pump, are in particular speed-controlled components. To control, in particular to regulate, the system and especially these components, a control module with power electronics is also provided, the power electronics having frequency converters for controlling the variable-speed components. The control module is a structural unit, specifically a compact structural unit, in which the power electronics are integrated.

The control module is preferably arranged as an independent structural unit, for example within the system housing or attached to the system housing. This structural unit in particular has a module housing in which the power electronics and preferably further control and regulation electronics are accommodated.

The previously mentioned components of the system are preferably preconfigured for connection on site, for example to a piping of the further circuit.

The power electronics itself is in turn preferably a power module designed as a structural unit, in which the respective frequency converters are implemented with corresponding electronic power circuits. According to the invention, the object is further achieved by such a control module, via which the operation of such a system with a refrigeration circuit can be controlled and is controlled during operation.

However, the control module is preferably also intended and used for other systems, in particular cooling systems and cooling systems, in which, for example, no refrigeration circuit is controlled via the control module and / or the system does not necessarily have a refrigeration circuit. In this case, the control module only has power electronics with a frequency converter for other variable-speed components such as pumps in a coolant circuit.

An example of such a further system are cooling systems in which a consumer-side cooling circuit is coupled with a primary circuit for heat dissipation. The primary circuit can be a normal water circuit, for example a domestic water network, or alternatively a refrigeration circuit. There is often a system separation between the consumer-side cooling circuit and the primary circuit - apart from the necessary heat exchange. The control module preferably controls the entire cooling system/the entire cooling system, especially the heat exchangers, circulation pumps, temperature control circuits with multi-way valves, etc. installed in it.

In summary, the invention is therefore not necessarily limited to systems with a refrigeration circuit, but can also be applied to a previously described cooling system, which typically, among other things, has a liquid/liquid heat exchanger and pumps as well as valves.

The preferred refinements and advantages listed below with regard to the system apply equally to the control module.

By integrating the frequency converters required for the variable-speed components into a common, uniform structural unit, in particular into the common power module, the need for several individual frequency converters as separate structural units for the different ones is eliminated variable speed components. This measure can save costs and the assembly effort is also low.

To form the power module designed as a structural unit, it is provided in particular that the necessary power electronics for forming the frequency converters for the (all) variable-speed components are arranged on a common circuit board.

In a useful further development, the control module has an integrated cooling plate for cooling the power electronics. The power module is specifically arranged on or on the cooling plate. The power module, in particular the circuit board, is in thermally conductive contact with the cooling plate. In particular, the circuit board or the power module rests over the entire surface of the cooling plate. This results in a particularly compact design with high efficiency. By integrating the power electronics in a common power module and at the same time cooling via a common cooling plate in a small installation space, reliable cooling is achieved at low costs. With a suitable cooling capacity, the components for the power electronics can also be small and therefore inexpensive. The individual cooling of the individual frequency converters that would otherwise be required is therefore no longer necessary.

According to a preferred embodiment, a cooling fluid flows through the cooling plate. This achieves a high cooling performance.

For this purpose, the control module expediently has cooling fluid connections through which fluid from the system is supplied to the control module during operation, i.e. the cooling fluid connections are connected to a fluid line in the system. This means that the cooling capacity for cooling the control module is taken directly from the system itself, so to speak as a waste product, and therefore no additional cooling unit, which independently generates cold, is required.

During operation, the control module is expediently connected to the further circuit via the cooling fluid connections, in particular to a hydraulic part the further circuit is connected within the system housing. The cooling plate is therefore cooled in particular using the coolant of the further circuit (coolant circuit).

In a preferred embodiment, the refrigerant of the refrigeration circuit is used for cooling. For this purpose, the cooling fluid connections are connected to the refrigeration circuit in a suitable manner.

According to a preferred further variant, an individual cooling circuit is provided for cooling the cooling plate, which is connected via a heat exchanger either to the further circuit or also to the cooling circuit for transmitting the required cooling capacity.

According to an alternative embodiment or in addition, the cooling plate is in thermally conductive contact with a component of the refrigeration circuit for cooling purposes, in particular with the evaporator. The cooling plate and thus the control module as a whole are therefore attached directly to a cold component of the refrigerant circuit, specifically to the evaporator. For this purpose, the cooling plate lies, for example, directly on a cold outside of the components, in particular of the evaporator. This is preferably a plate heat exchanger. In this embodiment, additional cooling via a cooling fluid and thus also the cooling fluid connections are preferably dispensed with.

Alternatively, the cooling via direct thermally conductive contact with the component is supplemented by cooling via a cooling fluid via the cooling fluid connections.

Preferably, the cooling power required for the control module and especially for the power module is provided exclusively via the cooling plate and further, in particular active, cooling measures for cooling the control module or the power electronics, for example by fans, are dispensed with. In a preferred development, the control module also has a heating element. This is preferably designed to heat the cooling fluid which flows through the cooling plate. As a result of this measure, heat is specifically introduced into the fluid, in particular coolant, of the further circuit during operation if necessary. This results in an overall increase in the coolant temperature.

Alternatively or additionally, the heating element - particularly in the embodiment in which the cooling plate and / or the control module is attached directly to the evaporator - serves to introduce heat into the evaporator and thus also indirectly into the coolant of the coolant circuit.

This temperature increase is preferably controlled in such a way that the formation of condensate on a heat exchanger through which the cooling fluid flows is at least reduced or avoided. For this purpose, a suitable intelligent control of the coolant temperature increase takes into account in particular the ambient temperature specifically at such a heat exchanger, the air humidity and / or the temperature of the cooling fluid.

In general, the control module has a connection for a flow and a return flow of the cooling fluid. The heating element preferably increases the return temperature during operation, i.e. H. the heating element is arranged in the flow direction at the end of or following the cooling plate. This measure allows the temperature of the cooling fluid to be raised if necessary.

In particular, an electrical resistance heater is used as the heating element.

For this purpose, a control circuit is preferably integrated within the control module, via which the heating element is controlled depending on sensor signals (e.g. air temperature, coolant temperature, air humidity...), etc. In a preferred development, overtemperature protection, specifically an overtemperature safety circuit, is also implemented in the control module.

In an expedient embodiment, the control module also has connections for data signals from or for sensors and actuators of the system. The control module specifically has connections for all sensors and actuators in the system.

Overall, the control module is designed and designed in a preferred embodiment for the complete control of the system. Further control components, which would have to be additionally arranged in a control cabinet, for example, are preferably dispensed with. In addition to controlling the performance components such as pumps, compressors and fans, all regulations and controls required for the operation of the system are also integrated in the control module. This particularly applies to the control of valves, e.g. an (electronic) expansion valve and/or another multi-way valve in the refrigeration circuit.

In particular, functions such as phase monitoring and/or a switching power supply are preferably integrated, via which the electrical power for the system is switched. The system is supplied with electrical power in particular via a multi-phase (three-phase) connection. The supply voltage is several hundred volts, e.g. 400 volts.

The control is optimized in particular with regard to the highest possible energy efficiency. This is supported by the integral training provided by the control module.

In particular, the control module is therefore an integrated control module for the entire system, which is arranged in particular within a compact module housing.

The control module and thus the module housing preferably has a size in the range of (250mm to 400mm) length * (100mm to 200mm) width * (100mm up to 200mm) height, and specifically a size of 320mm *150mm*150mm (+/- 20% per dimension).

The control module preferably has connections for the electrical and, if necessary, the hydraulic connection on the outside of the module housing. Unlike control cabinets, the module housing is usually closed, in particular the individual housing parts are connected to one another, for example via screws, and an interior is not accessible - for example through doors or other lockable openings. On the outside, the module housing has the necessary electrical and, if necessary, hydraulic connections.

In a preferred embodiment, the system is generally designed for a thermal power, in particular cooling power, of greater than 10kW, in particular greater than 50kW and especially greater than 100kW or even greater than 500kW. The thermal output is, for example, in the range of up to 1000kW.

It is expedient to generally dispense with a control cabinet that is otherwise common in such systems. In such a control cabinet, conventional switching devices and/or control devices and, if necessary, communication modules are typically snapped onto top-hat rails.

In order to make the control module as integrated as possible, the control module also has a communication interface for data signals from an input unit (user interface), alternatively or additionally for a remote maintenance interface or for communication with other systems.

In general, the control module is designed to process the data signals. This means that, on the one hand, incoming data signals, for example sensor signals, signals from the actuators or the communication signals mentioned are received, processed and converted into corresponding further signals. At the same time, the control module is also designed to output communication and control signals processed in this way or other in order to appropriately control the system and/or with external units, such as For example, a user interface, remote maintenance or exchanging data with other devices.

For this purpose, at least one further circuit board is expediently provided, on which corresponding circuits and circuits are arranged for processing the data signals. In particular, the control module therefore has, in addition to the power module, at least one further module, which has a corresponding circuit board with switching and electronic elements integrated thereon.

Due to this comprehensive integration of all or at least largely all of the components that are required to control the operation of the system, the overall wiring effort is kept very low, which makes assembly very simple.

In an appropriate further development, one or more and preferably all of the following components are integrated in the control module:

Phase monitoring is preferably integrated, through which the system is protected with regard to phase loss, phase inequality and phase reversal. Separate phase monitoring is preferably dispensed with.

A switching power supply is preferably also integrated in the control module, via which the required voltage supply for the components of the system, in particular for all components of the system, is provided. This means that the individual components of the system, especially the variable-speed components, are supplied with the required electrical power via the control module and, in particular, are also controlled with a suitable control voltage.

In a preferred embodiment, a valve control for at least one and preferably several and in particular all motor-driven valves of the system is also integrated in the control module. Here, too, there is no need for any other external valve controls. Exemplary embodiments of the invention are explained in more detail below with reference to the figures. These show partially simplified representations:

1 shows a perspective view of a refrigeration system,

2 shows a simplified diagram of a system,

3 shows a perspective view of a control module,

4 shows a further variant of a control module in an exploded view, FIG. 5 shows a greatly simplified, partial block diagram representation of a system and

6 shows an exemplary block diagram representation, in particular of the control module.

Figure 1 and Figure 2 each show a system 2, in particular a refrigeration system, to which a coolant circuit 4 is connected as a further circuit during operation. This is only shown in Figure 2, but not in Figure 1. The system 2 has a system housing 6, which typically has a frame made of profile rails and the side walls of which are covered with metal sheets. The system housing 6 accommodates components of a refrigeration circuit 8. These are in particular at least one heat exchanger, in the exemplary embodiment as a refrigeration system an evaporator 10, a variable-speed compressor 12 and in particular a throttle element designed as an electronically controlled expansion valve 14. Furthermore, a second heat exchanger is arranged within the system housing 6, which in the exemplary embodiment is designed as a refrigerant system as a capacitor 16. This capacitor 16 is assigned at least one fan and, in the exemplary embodiment, two fans 18 designed as fans to dissipate the heat to the environment. These are also speed controlled.

Some hydraulic components of the coolant circuit 4 are already arranged within the system housing 6. This applies in particular to a coolant pump 24. The hydraulic components of the coolant circuit 4 installed within the system housing 6 are connected to the remaining coolant circuit 4 in the connected state via hydraulic interfaces and hydraulic couplings which are arranged on the system housing 6. The coolant circuit 4 is routed via the evaporator 10, so that cold comes from Refrigeration circuit 8 is transferred to the coolant circuit 4. The coolant circuit 4 has a further heat exchanger 26, which releases the cold on the consumer side, for example to a refrigerated counter.

In Figure 1, some components, namely the fans 18, the compressor 12, the coolant pump 24 and the expansion valve 14 are shown outside the system housing 6 in the manner of an exploded view.

In the exemplary embodiment, a control module 22 is attached directly to the system housing 6 on a side wall, which preferably controls all functions of the entire system 2. As an alternative to mounting on the outside of a side wall, control module 22 can also be arranged inside the system housing 6 at a suitable location.

The system 2 is in particular a refrigeration system with a cooling capacity of preferably more than 10 kW, in particular more than 50 kW, more preferably more than 100 kW up to 1000 kW of cooling capacity. Alternatively, it can also be a heat pump with a corresponding heating output of the same magnitude.

An important aspect is the speed control of some of the main components of the system 2. These are in particular the compressor 12, the at least one coolant pump 24 or further pumps and the fans 18.

Traditionally, these components are each controlled with their own speed controller, which means, for example, a speed controller is installed in the compressor or in the pump. Conventional fans are a combination of EC technology and speed control. The speed controllers are therefore conventionally installed individually. Frequency converters are used for the speed controllers. The electrical components of the speed controller are conventionally air-cooled. The power electronics are therefore very limited in their application and ambient temperatures; the compressor frequency converters often have a limit of 45°C ambient temperature. Furthermore, as of today, the individual components in the electrical control cabinet are separately electrically protected, for example with motor protection switches. This leads to switch boxes of a larger dimension.

With this appendix 2, the first aspect aimed at is higher energy efficiency. In the EU, cooling systems for cooling industrial processes, for example, are gradually being regulated based on their energy efficiency (cooling capacity compared to electrical power consumption). The traditional method for precisely controlling the outlet temperature in process chillers is to divert hot gas from the compressor outlet to the evaporator inlet with a motorized hot gas bypass valve. This technique regulates the amount of refrigerant flowing through the condenser to control refrigeration capacity. The problem with this technique is that the compressor is constantly running at full power, doing work to compress the refrigerant vapor, even though it is not fully used for cooling. The current state of the art for precise temperature control in process chillers is the use of variable speed brushless DC compressors. The advantage of using variable speed compressors is that the compressor speed can be modulated to regulate the precise amount of refrigerant mass flow through the refrigeration system required for the applied heat load. This system does not require a hot gas bypass valve and the compressor only performs the minimum amount of work required for the heat load. The system presented here therefore does not require such a hot gas bypass line.

In addition to speed-controlled compressors, modern systems also use speed-controlled fans so that the fans deliver exactly the amount of air required to maintain the desired compressor pressure, but not less. The third element that influences the energy efficiency of process refrigeration machines is the coolant pump 24. In most cases, the system designer does not know the exact pressure drop that will occur in the refrigeration system. Therefore, refrigeration systems 2 are often oversized Coolant pumps 24 are designed that use a serial throttle or bypass valve to control the flow rate of coolant through the process. Any time a valve is used to regulate the flow of a pump, it means the pump is doing unnecessary work that is converted to heat by the pressure drop across the valve. This additional heat is absorbed by the coolant and must be dissipated by the refrigeration system. The most modern solution to controlling coolant flow is to operate the coolant pump 24 with a variable frequency drive so that the pump speed can be adjusted to provide the exact coolant flow required for the application.

The problem with building chillers with variable speed coolant pumps 24, fans 18 and compressors is that each device requires a frequency converter to control the speed of the device. These frequency converters tend to be quite expensive, typically accounting for 50-100% of the price of the components they are intended to drive.

A second aspect of the present invention is the simplification of the product portfolio. The refrigeration systems 2 provided by a manufacturer are used in a variety of applications ranging from medical imaging to laser cutting to semiconductor manufacturing. Each application has unique requirements for heat load, ambient temperature, coolant temperature, coolant supply pressure, coolant flow rate, communication with customer facility, etc. Due to the almost unlimited combinations of customer requirements, it becomes very difficult to control the complexity of the product portfolio, component inventory and manufacturing costs manage. The variability also makes it very difficult to control the scaling of production capacity.

The implementation of variable speed technology in Plant 2 immediately simplifies the portfolio as each specific plant configuration can be used for a much broader range of applications. For example, if the process pump is equipped with a frequency converter, one can Pump cover a wide range of flow and pressure requirements as the pump speed can be varied according to specific requirements. Likewise, the switch to variable speed compressors 12 allows a single compressor 12 to cover a wide range of process heat loads. By using variable speed fans 18, a single refrigeration machine can be operated in a wide range of environmental conditions.

A third aspect for the invention is ease of maintenance. The manufacturer of such systems 2 usually provides service support for systems 2 installed worldwide. These systems 2 are quite technical devices that can be difficult to diagnose and repair in the event of a malfunction. In addition, these systems 2 usually support process-critical systems. The possibility of integrating technology for remote monitoring of system 2 and predictive maintenance into the system is therefore of great value for the customer. This technology is quite expensive to integrate. It also poses a major connectivity challenge as many customers do not support third-party devices on their IT networks for security reasons. Wireless and cellular connectivity is also problematic as protocols are updated regularly and the typical lifespan of a Plant 2 is around 10-15 years.

The fourth aspect for the invention is cost reduction. The largest single item in the cost of chillers manufactured today is the materials and labor required for the control system. Due to design variability, most of the systems manufactured today 2 use a traditional industrial control cabinet with DIN rail mounted electrical components (i.e. circuit breakers, contactors, relays, etc.) and a PLC (Programmable Logic Controller) to control the system. This construction method offers a high degree of flexibility, but the components are expensive and assembly of the control cabinet is very time-consuming and requires highly skilled labor. In order to solve these problems, the integrated control module 22, described in more detail below, is arranged. The control module 22 integrates the functions of the frequency converter 38 (see FIG. 6) for compressor 12, coolant pump 24 and fan 18 and supports all sensor and actuator inputs and outputs as well as communication and remote connection for, for example, a remote Monitoring and maintenance of system 2.

The device design of the control module 22 in two different variants is shown in Figures 3 and 4.

The control module 22 each has a module housing 28, which has a large number of connections. On the one hand, electrical connections 30 are provided specifically for power supply and at least one data connection 32 for connecting data and communication lines. Furthermore, in the exemplary embodiment, two cooling fluid connections 34 are arranged, via which a cooling fluid can be passed through a cooling plate 36. The module housing 28 is in particular a multi-part housing which has an upper part and a lower part, the two parts forming a closed housing when connected.

The power electronics are integrated within the housing 28, which in particular have the frequency converters 38 required for the speed control of the various components (see FIG. 5) as suitable circuit components of the power electronics. For this purpose, in particular a circuit board 40 is formed, on which the power electronics are mounted. The circuit board 40 with the electronics mounted thereon forms an integrated power module 41.

A portion of the circuit board 40 or a further circuit board 40 is designed for processing the data signals and in particular has a plug part 42 into which a data plug of a data line can be inserted. As can be seen from the exploded view according to FIG. 4, a busbar 44 is arranged for the current-power distribution and is connected to the electrical connections 30. Furthermore, a direct voltage part 45 is shown in FIG. 4, which provides a suitable direct voltage for supplying the components for data and signal processing in particular.

Unlike traditional frequency converters that use large heat sinks and fans to dissipate heat from the power electronics, this control module 22 is designed to direct all heat generated by the power electronics to the cooling plate 36 so that the heat is dissipated via it .

This cooling plate 36 is cooled according to a preferred variant by circulating a cooled cooling fluid from the system 2 through the cooling plate 36. The cooling fluid is either the coolant of the refrigeration circuit 8, the coolant of the coolant circuit 4 or also a coolant of an independent circuit to which the cooling plate 36 is connected. The cooling fluid connections 34 are connected to the respective circuit in a suitable manner.

According to an alternative embodiment or in addition, the cooling plate 36 is connected directly to the evaporator 10 or another suitable component of the refrigeration circuit 8.

For effective cooling, the power electronics and in particular the circuit board 40 are in direct, thermally conductive contact with the cooling plate 36. For example, the underside of the circuit board 40 rests on a flat side of the cooling plate 36 and is, for example, glued to it or attached in some other way.

The cooling plate 36 is in particular a cuboid plate, for example, which is preferred - in the embodiment variant with the Cooling fluid connections - has internal cooling channels. The cooling plate is preferably made of metal.

Using the simplified diagram according to FIG. 5, control module 22 and its connection to the environment are shown in a simplified manner. In the exemplary embodiment, a total of three circuit boards 40 are shown, which take on different tasks. The printed circuit board 40 shown on the right forms the power module 41 with the power electronics attached thereto. The speed-controlled fan 18, usually several coolant pumps 24 and also usually several compressors 12 are controlled via corresponding outputs and interfaces. The different coolant pumps 24 are arranged, for example, in different coolant partial circuits. The compressor 12 shown in FIG. 2 can also be divided into several compressors, for example one being designed as a constant speed compressor and only the other as a speed-controlled compressor.

The two further circuit boards 40 are used in particular for communication and the processing of data signals. One is, for example, set up for communication with a user via a user interface 46. The other is set up for external communication via, for example, a telephone network or another computer network (Internet) and in particular allows remote access, for example for maintenance or for remote control.

Overall, the circuit board 40 also has a communication interface to actuators 50 and/or sensors 52 and is used to control the actuators 50 and/or to process data signals from the sensors 52. The sensors 52 are, for example, temperature sensors, pressure sensors, etc The actuators 50 are, for example, valves of the refrigeration circuit 8 or the coolant circuit 4. These two further circuit boards 40 can also be formed by a common circuit board. Typically, the entire electronics has one or more microprocessors 48, each of which is also mounted on the circuit boards 40.

Furthermore, the cooling fluid connections 34 are indicated by arrows in FIG.

Finally, Figure 6 shows a still schematic but somewhat more detailed circuit diagram of the control module 22: A main microprocessor 48 is used to control most processes. It communicates in particular with the power module 41 shown in dashed lines with the frequency converters 38 mounted thereon. The speed-controlled fans 18, the coolant pump 24 and the speed-controlled compressor 12 are controlled via the power module 41.

The main microprocessor 48 also monitors the cooling via the cooling plate 36 (FIG 3) and, for example, evaluates signals from a temperature sensor 52.

Furthermore, the power module 41 has a common rectifier circuit 54 for the frequency converter 38.

The main microprocessor 48 controls several control or data connections 46, which are suitably designed. A heating element 58 in particular is controlled via such a connection 46. This influences in particular the temperature of the coolant to the coolant circuit 4 in order to increase its temperature if necessary. For this purpose, the heating element 58 heats in particular the coolant of the coolant circuit 4 flowing through the cooling plate 36. In particular, it is attached, for example, on the output side after an outlet-side cooling fluid connection 34, for example in the manner of a heating sleeve. In the embodiment variant in which the cooling plate 36 is attached directly to a cold component of the refrigeration circuit 8 and in particular directly to the evaporator 10, heat is introduced into the coolant via the heating element 58 and thus indirectly into the coolant of the coolant circuit 4. This is preferred For this purpose, the heating element 58 is attached to or immediately in front of the evaporator 10.

For example, data is exchanged via a further connection 56 with an antenna 60, via which remote communication is then possible, for example via a cloud server 62 and via this with a remote workstation for remote monitoring or remote control.

Another connection 56 is designed for communication with further sensors 52.

For example, communication interfaces to external devices 64 or to an input/output unit 66 for user communication are formed via further connections 56.

Finally, electric motors 68, for example for valves, are also controlled via the main microprocessor 48.

As already mentioned, in addition to the speed-controlled components, components with a constant speed can also be provided. These are controlled via suitable relays 70, for example a compressor 12 or other valves or other actuators 72

Finally, various protection and monitoring circuits 74 are integrated within the control module 22, which are used, for example, for phase monitoring of a three-phase power supply 76.

The dashed border shown in FIG. 6 preferably indicates a respective circuit board 40 on the corresponding electronic one Components and circuit components are arranged. The dashed lines also define the logical boundary to the components arranged outside the control module 22.

The concept described here with the integrated control module 22 has the following advantages in particular.

• Integrating the drive circuits for the fans 18, compressor 12 and refrigerant pump 24 eliminates the need for three separate rectifier circuits for an AC/DC bus, reducing the total number of components required for the drive circuits.

• The direct cooling of the power electronics by the cooling plate 36 makes air heat sinks and cooling fans for cooling the power electronics unnecessary, which are therefore also omitted. In addition, more cost-effective power electronics that have a higher resistance can be used.

The control module 22 not only provides a cost-effective solution for implementing variable speed control for the components of the system 2, but also has the following features and advantages:

• By operating the fans 18, coolant pumps 24 and compressors 12 via an integrated frequency converter, system 2 can be operated independently of the mains frequency. Therefore, system 2 can be operated with the same mechanical components at both 50 and 60 Hz.

• By integrating the sensor and actuator I/O into the control module 22, the traditional industrial control cabinet is eliminated. In addition to space and cost savings, this also eliminates the need for a technician to wire the panel, which not only results in significant labor cost savings, but also eliminates many potential sources of error since the circuits are housed on a printed circuit board (PCB). • A phase monitoring circuit is incorporated into the control module 22 as one of the monitoring circuits 74, which protects the machine from phase loss, phase imbalance and phase reversal. It also eliminates the need to add a separate phase monitor.

• A switching power supply is integrated into the control module 22, which makes a separate control voltage supply unnecessary. It will also support both 50 and 60 Hz operation.

• A motorized valve control is integrated into the control module 22, which makes a separate motorized valve control module unnecessary.

• Since the power electronics are preferably cooled by the coolant of the system 2 or directly by the evaporator 10, there are no height restrictions for the system housing 6, as is common with most commercially available air-cooled frequency converters 38.

• A (resistance) heating element 58, preferably with a control circuit, is integrated into the control module 22, which enables the control module 22 to heat the coolant circuit 4, for example directly via the evaporator 10, making external resistance heating for cold environments or rapid warm-up unnecessary. In addition, an over-temperature safety circuit is preferably implemented to protect the heating element 58 from overheating, so that no additional heating limit switch is required.

• The control module 22 preferably includes a proprietary long-range wireless communications protocol that allows the system 2 to communicate wirelessly with a remote gateway module connected to the Internet. This gateway module supports Internet connections via LAN, WiFi and cellular. This allows the gateway module to be updated in the future when communication protocols are upgraded without having to make changes to Appendix 2. In addition, the end user can connect several systems 2 to the Internet via the same module, which can keep connection costs low. • The control module 22 includes connections for the sensors/actuators, fan, pump, compressor and mains power, so installation of the control module 22 is an assembly process and does not require qualified electrical engineers.

• The control module 22 can be cooled by circulating cooling fluid from the system 2 through the cooling plate 36 or by directly connecting the cooling plate 36 to the evaporator 10.

• The control module 22 includes a communication interface for reading pressure, flow and temperature data from multi-function sensors, thereby minimizing the number of physical sensors on the machine.

• The control module 22 includes an electronic circuit for controlling a fixed speed compressor that operates in conjunction with the variable speed compressor.

• The control module 22 contains a safety circuit for detecting refrigerant leaks and for automatically switching on an exhaust fan of the system 2 in order to remove potentially flammable refrigerant vapors from a cold room in which the Appendix 2, for example, is set up to be discharged.

Reference symbol list

2 facility

4 coolant circuit

6 system housings

8 refrigeration cycle

10 evaporators

12 compressors

14 expansion valve

16 capacitor

18 fan

22 control module

24 coolant pump

26 additional heat exchangers

28 module housings

30 electrical connection

32 data port

34 Cooling fluid connection

36 cooling plate

38 frequency converters

40 circuit board

41 power module

42 connector part

44 busbar

45 DC voltage part

46 user interface

48 microprocessor

50 actuator

52 sensor

54 rectifier circuit

56 control or data connection

58 heating element

60 antenna 62 cloud servers

64 external device

66 input/output unit

68 Motor 70 Relay

72 actuator

74 monitoring circuit

76 power supply

Claims

Claims System (2), in particular a refrigeration system, with a refrigeration circuit (8) and a connection for a further circuit (4) connected to it during operation, the refrigeration circuit (8) having an evaporator (10), a variable-speed compressor (12), a condenser (16) and a throttle element (14) and preferably also a variable-speed fan (18), further comprising a variable-speed pump (24) for circulating a fluid carried in the further circuit (4), and furthermore as a common one A control module (22) with power electronics is provided, which has frequency converters (38) for controlling the variable-speed components, namely fan (18), compressor (12) and pump (24). System (2) according to the preceding claim, wherein the power electronics are integrated in a common power module (41) and, for this purpose, are arranged in particular on a common circuit board (40). System (2) according to one of the preceding claims, wherein the control module has a cooling plate (36) for cooling the power electronics. System (2) according to the preceding claim, wherein a cooling fluid flows through the cooling plate (36). System (2) according to one of the two preceding claims, wherein the control module (22) has cooling fluid connections (34) via which a fluid from the system (2) is supplied to the control module (22) during operation. System (2) according to the preceding claim, wherein during operation the control module (22) is connected to the further circuit (4) via the cooling fluid connections (34). System (2) according to one of the two preceding claims, wherein during operation the control module (22) is connected to the refrigeration circuit (8) via the cooling fluid connections (34). System (2) according to one of claims 3 to 7, wherein the cooling plate (36) is in thermally conductive contact with a component of the refrigeration circuit (8) for cooling purposes, in particular with the evaporator (10). System (2) according to one of claims 3 to 8, wherein, in addition to the cooling plate (36), there are no further cooling measures for cooling the power electronics. System (2) according to one of the preceding claims, wherein the control module (22) has a heating element (58) for heating the cooling fluid, in particular in order to increase its return temperature. System (2) according to the preceding claim, wherein the temperature of the fluid in the further circuit (4) is increased with the aid of the heating element (58). System (2) according to one of the two preceding claims, wherein a control circuit is integrated in the control module (22), via which the heating element (58) is controlled. System (2) according to one of the preceding claims, wherein an overtemperature safety circuit is implemented in the control module (22). System (2) according to one of the preceding claims, wherein the control module (22) further has connections (56) for data signals from/for sensors (52) and actuators (50) of the system (2), in particular for all sensors (52) and actuators (50) of the system (2). System (2) according to one of the preceding claims, wherein the control module (22) has at least one communication interface for data signals from an input/output unit (66), a remote maintenance interface or for communication with other systems (2). System (2) according to one of the two preceding claims, wherein the control module (22) is designed to process the data signals. System (2) according to one of the preceding claims, wherein a phase monitoring circuit is integrated in the control module (22) and a separate phase monitoring device is preferably dispensed with. System (2) according to one of the preceding claims, wherein the control module (22) has at least one integrated switching power supply via which the required voltage supply for components of the system (2), in particular for all components of the system (2), takes place. System (2) according to one of the preceding claims, wherein a valve control for at least one and preferably several or all motor-driven valves of the system (2) is integrated into the control module (22), and further valve controls outside of the control module (22) are preferably dispensed with . System (2) according to one of the preceding claims, wherein the entire control for the system (2) is integrated in the control module (22). System (2) according to one of the preceding claims, which is designed for a thermal power in the range of greater than 10 kW, in particular greater than 100 kW, and in which there is no need for a control cabinet for controlling the system (2). System (2) according to one of the preceding claims, in which the control module (22) has a size in the range of (250mm to 400mm) length * (100mm to 200mm) width * (100mm to 200mm) height. Control module (22), designed to control a system (2), in particular according to one of the preceding claims, which is designed as a structural unit, wherein the control module (22) has power electronics which has frequency converters (38) for controlling variable-speed components.