WO2018100166A1

WO2018100166A1 - Method for operating a rotational-speed-variable refrigerant compressor

Info

Publication number: WO2018100166A1
Application number: PCT/EP2017/081206
Authority: WO
Inventors: Ulrich Gries; Jürgen Ewald Gläser; Allan Haue SLOT; Hans-Erik FOGH
Original assignee: Nidec Global Appliance Germany Gmbh
Priority date: 2016-12-01
Filing date: 2017-12-01
Publication date: 2018-06-07
Also published as: AT15779U1

Abstract

The invention relates to a method for operating a rotational-speed-variable refrigerant compressor (2) for cooling a cooling volume (4) of a refrigeration system (1), which refrigeration system does not have its own control unit, wherein the refrigeration system (1) comprises at least one thermostat (3) for directly or indirectly monitoring a temperature state of the cooling volume (4) and wherein the rotational-speed behavior of the refrigerant compressor (2) during a cooling cycle is controlled by means of a specification rotational-speed control stored in an electronic control device (6) of the refrigerant compressor (2). According to the invention, in order to enable adjustment of the rotational-speed behavior in reaction to a preceding special operating state and to enable energy-optimized cooling of the cooling volume (4) that is as fast as possible, at least one comparison parameter is stored in the electronic control device (6) of the refrigerant compressor (2) and exceedance or undershooting of the comparison parameter by a current measured parameter value is monitored, a special cooling cycle different from the specification rotational-speed control is triggered if the current measured parameter value exceeds or undershoots the comparison parameter, possibly, a current cooling cycle controlled by means of the specification rotational-speed control is interrupted by the special cooling cycle.

Description

METHOD FOR OPERATING A SPEED VARIABLE

KÄLTEMI TELVERDICHTERS

FIELD OF THE INVENTION

The invention relates to a method for operating a

Variable speed refrigerant compressor for cooling a cooling volume of a refrigeration system, wherein the refrigeration system

at least one thermostat for direct or indirect

Monitoring the monitoring of a temperature state of the cooling volume and wherein the refrigerant compressor is operated cyclically and a cooling cycle of the refrigerant compressor starts when the refrigerant compressor is set by a thermostat-triggered switching signal in an ON state and the

Cooling cycle ends when the refrigerant compressor is put into an OFF state by a further switching signal triggered by the thermostat, wherein an operating cycle in addition to the cooling cycle comprises a rest cycle following the cooling cycle, and wherein the speed behavior of the

Refrigerant compressor during a cooling cycle by means of a in an electronic control device of the

Controlled refrigerant compressor stored default speed control, and an electronic control device for controlling the cyclical operation of a variable-speed refrigerant compressor. Often the electronic

Control device of the refrigerant compressor also as

electronic control and regulating device of

Refrigerant compressor called.

Preferably, the speed behavior of

Controlled by the refrigerant compressor stored default speed control based on at least one predefined characteristic by the at least one predefined parameter is monitored for overshoot and / or undershooting by a current characteristic of a current cooling cycle. Variable speed refrigerant compressors are associated with a variety of different refrigeration systems, such as

Refrigerated cabinets, so for example refrigerators or racks, freezers, air conditioners or heat pumps, can be used. They offer over speed-resistant refrigerant compressors the advantage of being able to work more energy-optimized and the

Cooling capacity to be delivered to the cooling request

To be able to adjust the cooling volume.

Optimally come variable speed refrigerant compressor in refrigeration systems with its own electronic control unit and components for monitoring the operating condition of the

Refrigeration systems are used. Such refrigeration systems are referred to as intelligent refrigeration systems in the sequence. In this case, in the electronic control unit of the refrigeration system, which to the electronic control device of the

Refrigerant compressor is different, different

Processed switching signals, characteristics and parameters and generated from these input variables, a control signal which is transmitted to the electronic control device of the refrigerant compressor. This control signal may be

For example, be a speed specification, which, depending on the current temperature or the temperature profile of the cooling volume, the electronic control device of the

Refrigerant compressor specifies at what speed the

Refrigerant compressor to be operated or whether the electronic control device of the refrigerant compressor to turn this on or off. The operation, especially the speed behavior of a

variable speed refrigerant compressor, is in

intelligent refrigeration systems therefore by the interaction of the electronic control unit of the refrigeration system with the

controlled electronic control device of the refrigerant compressor, wherein the electronic control unit of the

Refrigeration system usually already specifically targeted

Refrigeration requirements transmitted to the electronic control device of the refrigerant compressor. However, the subject invention relates to a different type of refrigeration systems, namely those that have no electronic control unit that can communicate with the electronic control device of the refrigerant compressor and that do not have electronic components for monitoring the operating state of the refrigeration system

exhibit. Such refrigeration systems are therefore referred to as simple refrigeration systems in the sequence. They comprise at least one thermostat, which determines the temperature state of the

Cooling volume monitored and dependent on the current

Temperature state triggers a switching signal, which the

Refrigerant compressor placed in the ON state or put in the OFF state. Simple refrigeration systems communicate neither a speed specification to the electronic

Control device of the refrigerant compressor other data. They are also unable to others

To capture operating parameters such as the

Refrigerator temperature or its course and from it

Calculate refrigeration requirements for the refrigerant compressor.

The thermostat either requests or does not request refrigeration power, but does not quantify it, i. E. that the speed control of the refrigerant compressor is thus carried out exclusively by the electronic control device of the refrigerant compressor by programming them.

Nevertheless, the fundamental advantage of variable-speed refrigerant compressors over speed-resistant

To be able to use refrigerant compressors, it is necessary that that of the electronic control device of the

Refrigerant compressor controlled speed behavior of the

Refrigerant compressor is in terms of parameters to be defined, for example, as far as possible optimized in terms of energy consumption.

Under energy optimized as possible to understand that the power consumption or energy consumption of

Refrigerant compressor at the for each If necessary, cooling of the cooling volume required is particularly low and the refrigerant compressor can therefore be operated in a resource-saving manner. It is to be regarded as aggravating that the electronic control device of the refrigerant compressor of the

Refrigeration system receives no information about the operating condition, in particular no speed specification. This disadvantage is compensated in practice by the

The fact that simple refrigeration systems are characterized by the fact that they have a lower purchase price compared to intelligent refrigeration systems, is why they are still widely used worldwide.

STATE OF THE ART

Both variable speed and speed resistant

Refrigerant compressor, cause a circulation of a

Refrigerant in a sealed refrigerant system. The refrigerant is thereby absorbed by energy from the

Cooling volume heated in an evaporator and finally overheated and by means of the refrigerant compressor, too

Refrigerant compressor called, in a piston-cylinder unit by a in a cylinder housing

pumping piston is pumped to a higher pressure level, where the refrigerant emits heat through a condenser and is transported back into the evaporator via a throttle, in which a pressure reduction and the cooling of the refrigerant takes place. The movement of the piston is realized via a crank drive driven by an electric drive unit comprising a crankshaft. The above-described refrigerant process expires during a refrigeration cycle of the refrigerant compressor, wherein the

Refrigerant compressor is driven during the cooling cycle and one of the electronic control device of the

Refrigerant compressor has controlled speed behavior, wherein the electronic control device controls the electric drive unit of the refrigerant compressor.

A cooling cycle starts with a from the thermostat

Refrigeration system triggered switching signal, which the

Refrigerant compressor placed in the ON state.

For example, the thermostat triggers a switching signal for the ON state of the refrigerant compressor when the

Temperature level in the cooling volume or one

Cooling volume temperature or a temperature representative of the cooling volume temperature exceeds a predetermined maximum value. For the purpose of monitoring the temperature state of the cooling volume of the thermostat, for example, as a vapor pressure-based thermostat, in particular as

Bellows thermostat, be formed or a bimetallic strip or a NTC (negative temperature coefficient)

Have element as a temperature sensor.

The refrigerant compressor is driven or

remains in the refrigeration cycle in which the refrigerant

Process continues until the electronic control device of the refrigerant compressor receives a triggered by the thermostat further switching signal, which places the refrigerant compressor in the OFF state. The further switching signal can be triggered, for example, when the temperature level or a cooling volume temperature or one for the

Cooling volume temperature representative temperature has dropped below a predetermined minimum value due to the cooling cycle taking place in the cooling volume.

To enable the cooling of the cooling volume as energy-optimized as possible, the electronic control device of the refrigerant compressor operates during the cooling cycles according to a programmed specification, which determines the speed behavior of the

Refrigerant compressor during a cooling cycle regulates. This default speed control makes it possible that variable-speed refrigerant compressor even in simple refrigeration systems, which as mentioned above, even no electronic

Control unit equipped with the electronic Control device of the refrigerant compressor is able to communicate within the programmed preset

be regulated individually, for example, energy-optimized. The default speed control is set up such that at least one current, from the electronic

Control of the refrigerant compressor during a cooling cycle detectable characteristic with at least one, in the

electronic control device stored, predefined characteristic is compared and the speed behavior of the

Refrigerant compressor is regulated in dependence thereon. In other words, the refrigerant compressor is stored by means of the stored in the electronic control device

Default speed control based on at least one

predefined parameter regulated by the at least one predefined parameter in terms of over- and / or

Underflow is monitored by a current characteristic of a current cooling cycle. The at least one predefined characteristic variable can be a very wide variety of parameters, for example the electrical load of the refrigerant compressor, which electrical load is measured by measuring the electrical current through the refrigerant compressor, in particular by the electric current flowing through the electric drive unit of the refrigerant compressor, during the Cooling cycle is determined.

Preferably, however, it is in the

predefined parameter by the duration of a cooling cycle. The predefined parameter stands for that value of

Characteristic in which the most energy-optimized,

cyclic operation, for a given speed behavior during a cooling cycle, preferably at the lowest possible speed, in which the refrigerant compressor

driving electric motor can be operated with high efficiency is enabled. In other words, a temperature level in the cooling volume of the refrigeration system should be kept permanently as energy-optimized as possible by the default speed control. In the case of the duration of a refrigeration cycle as a predefined characteristic variable, for example, the preset speed control causes that when this predetermined duration is exceeded or fallen short of, ie when the time interval between the response of the thermostat

simple refrigeration system for switching on or off the

Refrigerant compressor is greater or less than that

predefined characteristic that the electronic

Control device of the refrigerant compressor whose speed changes either immediately or the next cooling cycle, with the aim that subsequent cooling cycles again have a duration that the predefined characteristic (duration)

correspond so that the refrigerant compressor in each

Cooling cycle can be operated as energy-optimized again.

Such a preset speed control for operating a variable-speed refrigerant compressor in a simple refrigeration system is known for example from DE 102013114374. In this case, the regulation of the rotational speed behavior takes place either during the current cooling cycle, wherein the rotational speed of the refrigerant compressor is increased when a

Exceeding the at least one predefined parameter (there duration of a cooling cycle) was detected by the current characteristic. Such an increase may also occur several times during a refrigeration cycle if the current characteristic exceeds a plurality of predefined characteristics, i. If, for example, despite increasing the speed of the thermostat still no switching signal for switching off the

Refrigerant compressor triggers because the temperature level or a cooling fluid temperature or one for the

Cooling volume temperature representative temperature in the cooling volume is still too high.

The increase can for example be progressive, degressive, linear or stepped. Recognizes the electronic control device, for example after several cooling cycles of the refrigerant compressor, that, even multiple, increasing the speed in each refrigeration cycle still does not mean that the predefined characteristic, for example, the predefined duration of a refrigeration cycle can be met, then according to the The technology also be provided that the starting speed of one or more subsequent cooling cycles is already set higher than is provided in the most energy-optimized case.

Equally, it can be provided that the starting rotational speed of a subsequent cooling cycle is reduced if the at least one predefined parameter is undershot.

How exactly the speed behavior of the

Refrigerant compressor due to the default speed control is dependent on the individual programming, which is specified by the refrigerant compressor manufacturer at delivery of the refrigerant compressor. It is essential

in any case, that the default speed control, which the

Speed during a cooling cycle regulates, depending on a predefined characteristic. The at least one predefined parameter is selected by the manufacturer of the refrigerant compressor such that previously known operating parameters of the refrigeration system, such as

For example, heat or cold losses in the cooling volume and / or in the refrigerant system and optionally too

expected ambient temperatures are taken into account so that the variable-speed refrigerant compressor runs as energy-optimized as possible due to the default speed control during a cooling cycle. In the case of deviations of a current parameter corresponding to the at least one predefined parameter from the at least one predefined parameter during a current cooling cycle, the

Default speed control to the speed behavior of the

To regulate refrigerant compressor so that as quickly as possible, either during the current cooling cycle or at least in a subsequent or within a few subsequent cooling cycles, the current characteristic again substantially corresponds to the predefined characteristic. A disadvantage of the control of the prior art is that the electronic control device of the

Refrigerant compressor is not capable of any

Special operating conditions, such as increased refrigeration demand after a defrost or after a power failure to respond. These special operating conditions and the associated

Problems are briefly described below.

Even simple refrigeration systems go through at certain intervals a defrosting process, the range of

Evaporator during a defrosting, for example via heating elements, is heated to form in the area of the evaporator in the cooling volume of the refrigeration system ice or

Remove or defrost frost deposits. This will help maintain effective cooling of the

Cooling volume guaranteed, as the ice or

Frost deposits, especially when they form a continuous layer, act as an insulating layer and hinder the heat exchange between the cooling volume and the evaporator. During defrosting, it inevitably comes to a heating of the refrigerant in the evaporator.

Simple refrigeration systems are usually so

controlled that a timer periodically triggers a defrost operation, if the refrigerant compressor has been set to the OFF state due to the further switching signal triggered by the thermostat. The thermostat does not trigger a switching signal during the defrosting process in order to prevent the

To put the refrigerant compressor in the ON state, so that the refrigerant compressor remains in the OFF state during defrosting. When the defrosting is completed, the thermostat is due to the detected by the heating of the evaporator deviation of the temperature level in the cooling volume or the cooling volume temperature or for the

Coolant temperature representative temperature the Switched signal triggered and the refrigerant compressor starts a cooling cycle according to the default speed control.

Another problem with simple refrigeration systems results from the fact that simple refrigeration systems often in

structurally weak regions in which a constant power supply is not guaranteed, but

Power interruptions are the order of the day. Depending on the duration of the power interruption, the temperature in the cooling volume increases. As soon as the power supply is restored, the thermostat will switch to the switching signal

triggered and the refrigerant compressor starts one

Cooling cycle according to the preset speed control. Because simple refrigerant compressor itself over no

Electronic control unit equipped with the

electronic controller of the refrigerant compressor is able to communicate in the electronic controller of the refrigerant compressor in both

Special operating conditions, ie after the end of a

Defrosting and after a power failure, a

Cooling cycle triggered in which the speed curve is controlled according to the default speed control. This has the consequence that the speed of the refrigerant compressor is gradually increased, so the available cooling capacity increases slowly, although the cooling requirement of the cooling volume after defrosting or due to the heating due to the

Interruption of the power supply, for cooling the cooling volume is substantially higher than a normal operational increase in the cooling demand, to which the

Default speed control is designed. As a result, the length of the following to the special operating condition

Cooling cycle is disproportionately higher than the duration of the previous cooling cycles and from the long duration of the

Cooling cycle increased energy consumption of the

Refrigerant compressor results. OBJECT OF THE INVENTION

It is therefore an object of the invention to overcome the disadvantages of the prior art and a method for

Operation of a variable-speed refrigerant compressor with an electronic control device to propose, so that when operating such a variable speed

Refrigeration compressor with a simple refrigeration system, which does not have its own electronic control unit, which with the electronic control device of

Refrigerant compressor can communicate, which is a

Adjustment of the speed behavior in response to a previous special operating state allows the refrigerator temperature as fast as possible and possible

energy-optimized to lower.

The invention relates to a method for operating a variable-speed refrigerant compressor as part of a simple refrigeration system, which does not have its own control unit, of the kind mentioned in the introduction. In the electronic control device of the

Refrigerant compressor a previous

To detect special operating state of the refrigeration system, the invention provides that in the electronic

Control device of the refrigerant compressor is stored at least one comparison parameter and an over- or

Below the comparison parameter is monitored by a current measured parameter value. While the

Monitoring the at least one characteristic in the

Target speed control is aimed solely at a regular operation of the refrigerant compressor and aims for a possible energy-optimized operation of the refrigerant compressor during such a control operation, the monitoring of the comparison parameter for detecting a previous special operating condition of the refrigeration system, in particular one Defrosting or interruption of power supply, designed and therefore provides one of which for the

Preset speed control necessary monitoring state separate, second monitoring state. However, it is conceivable that there is at least one

The comparison parameter is the same measured variable as the at least one characteristic but the measured variable is in

different procedures is monitored.

If the comparison parameter and the parameter are the same measured variable, it is necessary that the specifically defined values or value ranges of the comparison parameter and characteristic variable differ from one another. In particular, it may be provided that it is in the

Comparison parameter is a value of the measured variable, which is not assigned to the control mode or in which the control mode is no longer the optimal operating condition

represents, for example, by means of

Default speed control is no longer the required

Cooling capacity can be provided. In other words, the comparison parameter can represent a value of the measured variable that is outside of the means of the

Default speed control adjustable control mode is. The at least one comparison parameter is a variable that the electronic control device of the

Refrigerant compressor can detect and monitor itself without giving up additional information from one

Control unit of the refrigeration system, which is not available in simple refrigeration systems, to be instructed. In this case, the duration of operating cycles of the refrigerant compressor, in particular of the refrigeration cycle and rest cycle, as well as the load of the refrigeration cycle are conceivable as at least one comparison parameter

Refrigerant compressor measured as the flow of

Refrigerant compressor or one of the temperature of the

Cooling volume independent, further temperature. Also the

Monitoring two or three different

Comparison parameters, such as load and duration of an operating cycle or load and / or duration of an operating cycle as well as further temperature is conceivable, the at least one comparison parameter being two or three

Includes comparison parameters, each representing different parameters.

The same applies accordingly for the respective currently measured parameter value, each one

Assigned comparison parameter and accordingly adjusts to the same parameter as the assigned

Comparison parameter in order to detect an overshoot or undershoot of the comparison parameter or the value of the comparison parameter can. In other words, the current parameter value represents a currently measured value of the measured variable, which can be compared with the comparison parameter.

The comparison parameter can either be stored as a predetermined value in the electronic control device, that is already defined during manufacture, or be redefined during operation to allow the detection of defrosting as a deviation from the default speed control, as in more detail in the episode described. In this case, the value of the at least one comparison parameter represents a limit value which is set in such a way that when the comparison parameter is exceeded or undershot by the current parameter value, it can be concluded that a previous special operating state, in particular a defrosting process or an interruption of the current supply.

As soon as a previous special operating state has been detected, the refrigerant compressor is connected to one of the

Default speed control various special cooling cycle

operated in order to adapt the speed behavior of the refrigerant compressor to the effects of the special operating state and, if appropriate, to be able to supply a high cooling capacity to the cooling volume after the detection of the special operating state. Therefore, according to the invention, it is provided that a special cooling cycle different from the preset speed control

is triggered if the current measured parameter value exceeds or falls short of the comparison parameter. The detection of the special operating state can at any time one

Operating cycle, for example, during the

Resting cycle, directly at the beginning of a cooling cycle or during a cooling cycle, depending on which comparison parameter is monitored. For example, if done

Detection may be provided during the rest cycle or at the beginning of the cooling cycle that the special cooling cycle is started instead of a conventional conventional cooling cycle intended. In this case, the one triggered by the thermostat triggers

Switching signal, which sets the refrigerant compressor in the ON state, the special cooling cycle. Is this done?

Detection of the special operating state during a cooling cycle, it is provided that the cooling cycle is interrupted and the special cooling cycle is started.

The special cooling cycle is usually characterized by a speed behavior with an average speed, which is increased compared to the average speed of the default speed control. Immediately by increasing the middle

Speed of the refrigerant compressor results in increased cooling capacity of the refrigerant compressor. Under medium

Speed while the speed is averaged, such as

Arithmetic, geometric or harmonic mean, understood over the duration of the cooling cycle.

Therefore, the previously asked task in a

inventive method of the type described above for a simple refrigeration system solved in that

in the electronic control device of

Refrigerant compressor is stored at least one comparison parameter and an overshoot or undershoot the

Comparison parameters by a current measured

Parameter value is monitored,

one different from the default speed control

Special cooling cycle is triggered if the current measured parameter value exceeds or exceeds the comparison parameter

below,

- where appropriate, an updated version by Default speed control controlled cooling cycle by the

Special cooling cycle is interrupted.

Analogously, the invention also relates to an electronic

Control device for controlling the cyclical operation of a variable-speed refrigerant compressor, wherein the

electronic control device is arranged to

the refrigerant compressor due to one of a

Thermostat for direct or indirect monitoring of a temperature condition of a cooling volume of a refrigeration system triggered switching signal to start a cooling cycle and to end a rest cycle and

- turn off the refrigerant compressor due to a triggered by the thermostat further switching signal to end the cooling cycle and to start a rest cycle and

- The speed behavior of the refrigerant compressor during a cooling cycle by means of a in the electronic

Control device stored default speed control to regulate.

The object stated in the introduction is achieved in that at least one comparison parameter in the electronic

Control device is stored and the electronic

Control device is set up

to detect an overshoot or undershoot of the comparison parameter by a current measured parameter value,

one different from the default speed control

Special cooling cycle trigger when the current measured

Parameter value overrides the comparison parameter or

below,

- if applicable, a current one, by

Preset speed control regulated cooling cycle to start the special cooling cycle.

In one embodiment variant of the method according to the invention, it is provided that the at least one

supervised comparison parameters by a load of

Refrigerant compressor is in a start phase of a refrigeration cycle. On the one hand, the load of the

Refrigerant compressor as operating parameters, since these in simple manner by measuring the electric current through the refrigerant compressor, in particular by the electrical drive unit of the

Refrigerant compressor electrical energy flowing during the cooling cycle is detected. The start-up phase of the cooling cycle begins as soon as the refrigerant compressor has been switched to the ON state due to the receipt of the thermostat-triggered switching signal.

The example of a previous defrosting is the

Principle briefly explained: Due to the heating of the refrigerant in the evaporator during the defrosting process or

Due to the high refrigeration demand is the burden of

Refrigerant compressor after a previous defrosting particularly large. If the load currently measured exceeds the reference value of the load stored as a comparison parameter, the electronic control device of the

Refrigerant compressor closed on a previous defrosting and the special cooling cycle is started. As a rule, a current cooling cycle is interrupted for starting the special cooling cycle, in other words the

Subject to preset speed control to perform the special cooling cycle. The electronic control device of the refrigerant compressor has circuits or

electronic components over which the at least one operating parameter can be determined or measured.

In an analogous way is also in one

Embodiment of the electronic invention

Control device provided that the electronic

Control device is adapted to a load of

Refrigerant compressor as a current through the

To measure refrigerant compressor and that it is the stored comparison parameter and the currently measured parameter value to loads.

If the monitored comparison parameter is the load, it is advantageous not to set a concrete value of the load as the comparison parameter, since the Would increase the risk of misdetection. It is much more expedient to use an average load, which is averaged over a defined starting phase of the refrigerant compressor. By average load is meant the mean value of the loads, ie the sum of all detected individual loads during the starting phase averaged, for example as

arithmetic, geometric or harmonic mean, for the duration of the starting phase. This allows individual

Outliers of the load are compensated and a load behavior can be mapped. In addition, the previous special operating state can be better monitored by monitoring the average load, since due to the heating of the refrigerant in the refrigerant system, the load of the refrigerant compressor over the start phase of the refrigeration cycle, usually at least over the first 30 s of the refrigeration cycle, is relatively large. Therefore, in a further embodiment of the invention

Provided that the load as an average load, averaged over the duration of the starting phase, the duration of the starting phase is preferably between 10 s and 90 s, in particular between 30 s and 80 s, more preferably between 40 s and 70 s is monitored ,

Also, the duration of the idle cycle is particularly suitable as a comparison parameter, since during normal operation according to the default speed control, the duration of the idle cycle usually does not exceed a maximum value. Therefore, in a further embodiment of the invention

Provided that the at least one monitored comparison parameter is a duration of the rest cycle. In other words, due to the cold losses and / or insulation losses in the cooling volume is a duration

within which the target temperature state of the cooling volume is left after the end of the cooling cycle and thus the next cooling cycle is triggered. However, the special operating state usually leads to a longer duration of the rest cycle, for example up to 15

Minutes. For example, if the monitored operating parameter is the duration of the rest cycle, the comparison parameter is the maximum value of the duration of the rest cycle Are defined. If the actual duration of the current idle cycle exceeds the comparison parameter, then the

electronic control device from this deviation from the fact that the refrigeration system just a defrosting

passes. Therefore, at the entrance of the next from

Thermostat triggered switching signal immediately the

Special cooling cycle to be started. It is of course conceivable that both the load and the duration of the idle cycle are monitored by the electronic control device and the special cooling cycle is triggered if, at least due to the monitoring of one of the two monitored parameters,

preferably both monitored parameters, to one

previous defrosting is closed and the

Special cooling cycle is triggered.

In an analogous way is also in one

Embodiment of the electronic invention

Control device provided that the electronic

Control device is adapted to a duration of the

Determine idle cycle and that the stored comparison parameter and the currently measured parameter value is the duration of a rest cycle.

In order in particular to detect an interruption of the power supply as a previous special operating state, in a preferred embodiment of the invention

provided that

a further temperature independent of the temperature of the cooling volume is measured,

if the currently measured parameter value is the further temperature,

- It is the at least one monitored

Comparison parameter is a reference temperature ..

The detection and transmission of the additional temperature, which is independent of the monitored by the thermostat temperature level of the refrigerant compressor, provides an additional

Information on the switching signals of the thermostat for the electronic control device of the refrigerant compressor As a rule, the further temperature of one

Measured temperature measuring device, which is part of the electronic control device of the refrigerant compressor or on a housing of the refrigerant compressor

is arranged. Thus, the further temperature gives one

Conclusion on the operating temperature of the electronic control device of the refrigerant compressor. By the

Comparison of the currently measured additional temperature as currently measured parameter value and the comparison temperature as a comparison parameter, it can be determined, for example, that the refrigerant compressor was not in operation for a long period of time, if the currently measured additional temperature is below the reference temperature. Thus, it can be concluded on the monitoring of the additional temperature to a previously occurred special operating state, ie about a defrost or a

Interruption of the power supply.

In an analogous manner is in a further preferred embodiment of the inventive electronic

Control device provided that the electronic

Control device is connected to a temperature measuring device for measuring an independent of the temperature cooling volume, further temperature, and that the stored comparison parameter is a comparison temperature and the currently measured parameter value is the further temperature. The temperature measuring device can

For example, be designed as a probe, a resistance thermometer, a thermocouple or a temperature sensor.

Usually, electronic controllers are capable of detecting a previous power interruption. However, they are unable to determine how long the power supply was interrupted. In the case of a brief interruption, it would not be expedient to trigger a special cooling cycle since only a small additional cooling requirement prevails in the cooling volume. Therefore, a special cooling cycle is triggered only when the electronic control device of Refrigerant compressor has detected an interruption of the power supply and the comparison parameter is exceeded or fallen below by the currently measured parameter value. This ensures that the special cooling cycle is triggered only when an interruption of the power supply has been detected and due to the overshooting or undershooting of the comparison parameter by the currently measured

Parameter value has been verified that actually an increased cooling demand prevails in the cooling volume.

Preferably, for the inference to a

Interruption of the power supply either the load, in particular the average load, or the other temperature used as currently measured parameter value, wherein the

Comparison parameter in the first case also represents a load, in particular a medium load, or represents a comparison temperature in the second case. For example, the deviation of the currently measured temperature from the comparison temperature, which deviation from the cooling of the electronic control device of the refrigerant compressor or the cooling of the refrigerant compressor itself

results, to be closed for the duration of the power interruption. It is therefore provided in a particularly preferred embodiment of the method according to the invention that

the electronic control device of

Refrigerant compressor monitors whether a power supply of the electronic control device has been interrupted,

- and the special cooling cycle is triggered when both a

Exceeding or undershooting the comparison parameter by the currently measured parameter value as well as a previous interruption of the power supply are detected. Likewise, this advantageous behavior is achieved in an electronic control device according to the invention by

the electronic control device is set up to

- to detect an interruption of the power supply and - Trigger a special cooling cycle when both an overshoot or undershoot of the comparison parameter was detected by the currently measured parameter value as well as a previous interruption of the power supply.

In a particularly preferred embodiment of the

inventive electronic control device is

provided that the temperature measuring device is part of the electronic control device of the refrigerant compressor or that the temperature measuring device is arranged on a housing of the refrigerant compressor to a

Can determine operating temperature of the electronic control device of the refrigerant compressor or the refrigerant compressor.

Usually, the electronic control device of the refrigerant compressor already has other purposes,

For example, to monitor the temperature of

electronic control device for preventing a

Overheating, a temperature measuring device, so that the electronic control devices by implementing this aspect of the invention are not expensive and the

Measured values of this temperature measuring device as

According to the invention further temperature can be used.

An additional advantage of using the readings of an already in a conventional electronic

Control device provided temperature measuring device as a further measured temperature is that only the programming of the electronic control device of the

Refrigerant compressor must be changed and not the structure of the electronic control device itself. This can also be already in use

Refrigerant compressor in a simple way to

Adapt implementation of the method according to the invention.

Similarly, in a second particularly preferred

Embodiment variant of the invention provided that the further Temperature is measured by a temperature measuring device and the temperature measuring device to a housing of the

Refrigerant compressor is mounted. There

Refrigerant compressor and electronic control device of the refrigerant compressor usually as an assembly

manufactured and supplied to the manufacturer of a refrigeration system, the functionality of the method according to the invention can also be ensured if the

Temperature measuring device on the housing of

Refrigerant compressor is arranged. This is the

Temperature measuring device Part of the delivered module and the functionality of the method is guaranteed regardless of any assembly or connection errors of the manufacturer of the refrigeration system. Particularly preferred is the

Temperature measuring device arranged on an outside of the housing, while the components of the

Refrigerant compressor, so at least the electrical

Drive unit and the piston-cylinder unit, are arranged inside the housing of the refrigerant compressor.

To the detection of a special operating state in a simple manner due to a change of the current

Operating state of the refrigerant compressor to allow, without one in the control of the

Refrigerated compressor deposited to have to resort to predefined stored comparison parameters in the delivery state is in another preferred

Embodiment of the method according to the invention

provided that the at least one measured current

Parameter value in the electronic control device of

Refrigerant compressor is stored over at least two operating cycles as a stored parameter value. Thus, the development of the stored parameter values indicates a special operating state. Preferably, the stored parameter values are above 3, 4, 5, 8 or 10

Operating cycles stored in order to map and monitor the performance as accurately as possible. If the currently measured parameter value is the further temperature, for example, the measured further temperature at the beginning of the cooling cycle and / or the measured further temperature at the end of the cooling cycle

get saved. For example, on the

stored temperatures are determined at the beginning of a cooling cycle and / or at the end of a cooling cycle, a cooling rate over which an expected further temperature at the beginning of the next cooling cycle is determined, wherein the expected further temperature as the comparison temperature, optionally including a multiplicative deviation factor is defined.

Thus, it is advantageous if the comparison parameter is not fixed in the electronic control device of

Refrigerant compressor is predefined, but in

Dependence of an extreme value, ie a maximum value or a minimum value, of the stored parameter values,

for example, including a multiplicative

Deviation factor, constantly changed. It is also conceivable that the extreme value of the stored parameter values is determined and is used directly as a comparison parameter. Therefore, in a particularly preferred

Embodiment variant of the invention provides that in the electronic control device of the refrigerant compressor, an extreme value of the stored parameter values is selected and the comparison parameter as a function of

Extreme value of the stored parameter values is determined, preferably corresponding to the extreme value.

Instead of the extreme value, an average value of the stored parameter values for the most accurate is also suitable

as accurate as possible mapping and monitoring of

Operating behavior of the refrigerant compressor. The mean value can be calculated, for example, as a geometric, arithmetic or harmonic mean of the stored parameter values. Again, the comparison parameter depending on the mean, for example, under

Inclusion of a multiplicative deviation factor, ongoing changed. Likewise, it is again conceivable that the mean value of the stored parameter values is determined and used directly as a comparison parameter. Thus, for example, the current load or the current average load and / or the current duration of the rest cycle and / or the measured additional temperature with the

corresponding from the stored parameter values

certain extreme values and / or averages are compared to reliably to a special operating condition

close and accordingly trigger the special cooling cycle.

It is to be regarded as particularly advantageous that the comparison parameter can take into account possible fluctuations of the operating state by a predefined, in the

multiplied electronic control device of the refrigerant compressor multiplied by the extreme value or the average value to define the comparison parameter. Thus, operational fluctuations in the current parameter values do not trigger a special cooling cycle. Therefore, in another particularly preferred

Embodiment provided that the comparison parameter is determined by multiplying the extreme value or the mean value with a deviation factor, wherein the

Deviation factor at least 1.25, preferably at least 1.50, more preferably 1.75, in particular 2.0.

According to the prior art, the default speed control can be designed such that, depending on the

Speed behavior of a current operating cycle,

For example, maximum speed or average speed, a new starting speed for the subsequent cooling cycle is set. If no detection of the special operating state takes place and thus no special cooling cycle can be triggered, but a normal cooling cycle follows the special operating state, then the long duration of this cooling cycle and the high speed also have a negative effect on the following operating cycles: The increased cooling demand results solely from the Effects of the special operating state and not on a generally higher cooling requirement of the cooling volume.

Nevertheless, according to the default speed control, the speed of the subsequent refrigeration cycle is increased, so that the refrigerant compressor is not distributed energy-optimized. The higher the average speed on the

Special operating state following cooling cycle was, the greater the number of cooling cycles must be passed through, until the speed to the required speed

has set. Since according to the invention, however, a detection of the special operating state takes place, this disadvantage of the prior art can be overcome by the fact that the

Special cooling cycle when determining the start speed of the cooling cycle following the special cooling cycle

is taken into account, but on a, stored in the electronic control device, starting speed default from the last completed cooling cycle. Therefore, in a particularly preferred embodiment of the invention, it is provided that a starting rotational speed of the refrigerant compressor for the cooling cycle following the special cooling cycle is set to a value stored in the electronic control device.

A particularly effective cooling of the cooling volume in response to a special operating state, such as a defrosting operation or the interruption of the energy supply is achieved in a further embodiment of the invention in that the refrigerant compressor is operated during the special cooling cycle such that the cooling volume, a higher average cooling capacity is supplied than at a comparable cooling cycle controlled according to the default speed control. The increased cooling capacity is achieved by an increased speed of the refrigerant compressor. A preferred embodiment of the invention

Method provides that the refrigerant compressor is operated during the special cooling cycle such that a

defined speed is not exceeded until the end of the special cooling cycle, wherein the defined speed at least 75%, preferably at least 85%, particularly preferably at least 90%, in particular between 95% and 100%, of a maximum speed of the refrigerant compressor is. A high value of

defined speed, which is to be understood as a minimum speed, in relation to the maximum speed of the refrigerant compressor provides the provision of a high cooling capacity or

Cooling capacity through the refrigerant compressor safe. In this case, the refrigerant compressor, for example, over a first defined period of time with a first defined speed of 95% of the maximum speed can be operated over a second defined period of time with a second defined speed of 80% of the maximum speed, wherein the cycles repeat alternately until the special cooling cycle ends. In order to be able to reduce the high temperature of the cooling volume due to the special operating state as quickly as possible, ie to be able to provide a high cooling capacity immediately after the detection of the special operating state, in a further embodiment variant of the invention it is provided that the

Refrigerant compressor is accelerated to a predefined speed at the beginning of the special cooling cycle, wherein the at least one defined speed at least 70%, preferably more at least 80%, more preferably at least 90%, in particular between 95% and 100%, a maximum speed of

Refrigerant compressor is.

The object stated at the outset is also solved by comprising an assembly

- A variable-speed refrigerant compressor with an electric drive unit and a drivable by the electric drive unit piston-cylinder unit for

Compression of refrigerant;

- An electronic control device according to the invention for controlling the cyclical operation of the variable speed

Refrigerant compressor according to a method of the invention. Such an assembly can be installed in a simple manner in a refrigeration system without a control unit of the refrigeration system to a control signal or a speed specification the electronic control device of

Refrigerant compressor transmitted.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be explained in more detail with reference to exemplary embodiments. The drawings are exemplary and are intended to set forth the inventive idea, but under no circumstances

narrow down or even finish playing.

Showing:

Fig. 1 is a schematic representation of a back of a

Refrigeration system;

Fig. 2 is a schematic representation of a

Refrigerant compressor with another

Variant of the electronic

Control means;

Fig. 3 is a schematic representation of the speed behavior of three different cycles of

Refrigerant compressor in one

Predictive speed control;

Fig. 4 is a schematic representation of the speed behavior after a defrost according to the

Default speed control according to the prior art;

5 shows a schematic representation of the rotational speed behavior after a defrosting process according to a first embodiment variant of the method according to the invention;

Fig. 6 is a schematic representation of the speed behavior after a defrost according to a second

Variant of the method according to the invention;

Fig. 7 is a schematic representation of the speed behavior after a power failure according to a third embodiment of the method according to the invention.

WAYS FOR CARRYING OUT THE INVENTION Figure 1 shows a simple refrigeration system 1 with a variable-speed refrigerant compressor 2, a

Refrigerant line 5 and an evaporator 5a.

Refrigerant compressor 2, refrigerant line 5 and

Evaporator 5a form a closed refrigerant system with, in which refrigerant circulates during operation, ie during a cooling cycle C _{K of} the refrigerant compressor 2, refrigerant. The refrigeration system 1 has a

Cooling volume 4, which can be withdrawn heat by the evaporator 5a or cooling power can be supplied by the refrigerant evaporates in the evaporator 5a.

The individual components of the refrigerant compressor 2, so at least one piston-cylinder unit in which the refrigerant is cyclically compressed and an electric

Drive unit, via which the piston-cylinder unit is driven, are within a housing 8 of the

Refrigerant compressor 2 is arranged. The variable-speed refrigerant compressor 2 also has a

electronic control device 6 for controlling the

Speed behavior of the refrigerant compressor 2, which is connected to the electric drive unit and this drives. In order to enable the cooling of the cooling volume 4 as energy-optimized as possible, the electronic control device 6 of the variable speed works

Refrigerant compressor 2 during the cooling cycles C _K according to a programmed default, which regulates the speed behavior C _{K of} the refrigerant compressor 2 during a cooling cycle C _K. This default speed control allows the

variable speed refrigerant compressor 2 in the simple

Refrigeration system 1 can be operated while ensuring the most energy-optimized operation possible. The programmed default is already at the

Programming the electronic control device 6 of the refrigerant compressor implemented and represents, so to speak, a standardized delivery state, which allows the most energy-optimized operation in a variety of standard use conditions. Usually, the variable-speed refrigerant compressor 2 and the electronic control device 6 of a

Refrigerant compressor manufacturer assembled as an assembly and sold as a unit to the manufacturer of refrigeration systems. The inventive method or the inventive electronic control device of the refrigerant compressor for adjusting the operation of the refrigerant compressor

Special operating conditions, the high cooling capacity of

Refrigerant compressor 2 will require in the sequence

described in detail.

The refrigeration system 1 itself has no independent

Control unit on which the control device 6 of the

Refrigerant compressor 2 switching signals, characteristics and

Measurements can provide or transmitted a control signal, which contains a speed specification. The only switching signal, which the simple refrigeration system 1 to the

Control device 6 of the refrigerant compressor 2 transmitted, comes from a thermostat 3, depending on the

Temperature levels of the cooling volume 4. For this purpose, the

Thermostat 3 usually has a temperature sensor on,

for example, a bimetallic strip or a

vapor-pressure-based measuring element or an NTC (negative

Temperature coefficient) element, which is arranged in the cooling volume 4, to measure the temperature of the cooling volume 4 directly, or is arranged on the evaporator 5a to the

Temperature of the cooling volume 4 indirectly to certain.

Preferably, the thermostat 3 is vapor pressure-based

Bellows thermostat formed. The thermostat 3 is designed to trigger a switching signal, which to the

Control means 6 of the refrigerant compressor 2 is transmitted or to transmit a switching signal to the control device 6, which switching signal sets the refrigerant compressor 2 in an ON state in which the drive unit is activated and refrigerant is compressed in the piston-cylinder unit. The thermostat 3 is designed to trigger a further switching signal, which to the

Control device 6 is transmitted or another

To transmit the switching signal to the control device 6, which further switching signal sets the refrigerant compressor 2 in an OFF state in which the piston-cylinder unit is not exposed to drive torque. According to one aspect of the invention is a

Temperature measuring unit 7 is provided, via which an independent of the temperature of the cooling volume 4, another

Temperature T _{w is} measured. In the present

Embodiment variant is the temperature measuring unit 7 as

Formed part of the control device 6,

for example as an onboard sensor on a circuit board

Control device 6.

Figure 2 shows a second embodiment of the invention in which the temperature measuring unit 7 on the housing 8 of

Refrigerant compressor 2 is mounted. The housing 8 of the refrigerant compressor 2 may be, for example, a hermetically encapsulated housing 8, which is a

Housing lower part 8a and a housing upper part 8b includes. In the present embodiment, the

Temperature measuring unit 7 on an outer surface of

Housing top 8 b attached. The reference numerals 7 ^λ and 7 ^{λ λ} indicate dashed alternative shown

Fixing position on an outside of the

Housing lower part 8a, whereas the reference numeral 7 ^{λ λ λ} denotes a dashed illustrated alternative mounting position on a post of the refrigerant compressor 2.

FUNCTIONING OF THE INVENTION

In the following, a method for operating the variable-speed refrigerant compressor 2 in a simple refrigeration system 1 will be described with reference to Figure 3, as it is already known from the prior art. It should in particular the control of the speed behavior of the variable-speed refrigerant compressor 2, the so-called

Default speed control, to be entered, at which the

Speed behavior of the refrigerant compressor 2 during a Cooling cycle C _K on the basis of at least one in the

electronic control device 6 of

Refrigerant compressor 2 stored, predefined

Characteristic K _{v is} controlled and the at least one predefined parameter K _{v is} monitored for overshoot and / or undershooting by a current characteristic K _{a of} a current cooling cycle C _Ka .

In the present exemplary embodiment, the at least one predefined parameter K _v is the duration of a cooling cycle C _K. In this case, the current running time and the actual duration of the cooling cycle C _{K are} monitored by the electronic control device 6.

In FIG. 3, three operating cycles C 1, C 2, C 3 are shown by way of example which show different rotational speed characteristics of the engine

speed variable refrigerant compressor 2 represent, which can adjust during operation. One

Operating cycle C is made up of one each

Closed cycle C _R and a cooling cycle C _K together, the

Refrigerant compressor 2 during a cooling cycle C _{K is} in operation and forcibly circulated refrigerant for cooling the cooling volume 4 by the refrigerant system. In the rest cycle C _R, however, the refrigerant compressor 2 is switched without drive and there is essentially no cooling of the cooling volume 4th

The first cooling cycle C _K i is initiated at the time ti by the triggered by the thermostat 3 switching signal, wherein the refrigerant compressor 2 of the electronic

Control device 6 is set in an ON state. The thermostat 3 triggers the switching signal when a deviation of the temperature level of the cooling volume 4 is detected from a predetermined temperature level, which suggests a cooling demand in the cooling volume 4, so that the cooling volume. 4

Refrigeration must be supplied through the refrigerant compressor 2. In the present case, at the time ti exceeding the predetermined temperature level of

Thermostat 3, or by the temperature sensor of the thermostat 3, measured. The temperature in the cooling volume 4 is therefore too high. Once the variable speed refrigerant compressor 2 is set in the ON state, it is operated at a start speed vi. At the time t ₂ , which corresponds to the predefined duration of the cooling cycle C _K i, the predetermined temperature level in the cooling volume 4 has not yet been reached, and the thermostat 3 has accordingly not triggered a switching signal to the

Set refrigerant compressor 2 in the OFF state.

There is thus at the time t ₂ further cooling demand in

Cooling volume 4. Since the actual refrigeration demand of the

Cooling volume 4 of the electronic control device 6 is not known, the speed v by a predetermined value, for example, 10%, 20%, 30% or 50%, the current

Speed vi increased to a first increased speed v ₂ . This ensures that the refrigeration demand in the cooling volume 4 can be covered more quickly, or at very high refrigeration demand at all, or the refrigeration cycle C _K can be terminated quickly.

At time t3, which is a limit of one in the

predefined running time K _v stored record corresponds, the refrigeration demand of the cooling volume 4 is still not satisfied, so in the present example, another

Increasing the speed v for the reasons mentioned above to a second increased speed v ₃ occurs.

At time t ₄ receives the electronic control device 6 triggered by the thermostat 3 further switching signal, which signals that the refrigeration demand in the cooling volume 4 is satisfied and the temperature within the cooling volume 4 is within the necessary for cooling predefined temperature levels. Due to the further switching signal, the electronic control device 6 sets the refrigerant compressor 2 in the OFF state, whereby the second idle cycle C _{R2 is} triggered. The elapsed time between times ti and t ₄ time corresponds to the actual duration Ki of the first

Cooling cycle C _K i · Since the actual duration Ki is greater than the predefined duration K _v can either be provided that the next cooling cycle C _K2 unchanged according to Default speed control is started, with the risk that as in C _K i needs to be readjusted, or it can

be provided that the electronic control device 6 goes from an increased refrigeration demand in the subsequent cooling cycle C _K 2. The latter can be the case in particular if cooling cycles C _K already exist before the cooling cycle C _K i whose duration was longer than the predefined running time K _v .

To accommodate the expected higher cooling demand of the cooling volume 4 concern and to deliver them within the predefined duration K _v of the next cooling cycle C _K 2, the following refrigeration cycle C _K 2 which is in turn triggered by the switching signal, with an increased starting speed v ₄ operated.

The increased starting speed v ₄ can correspond, for example, to the last speed v of the preceding cooling cycle C _K i or as the mean value of the speeds vi, v ₂ , v _{3 of} the preceding ones

Cooling cycle C _K i be calculated.

In the second cooling cycle C _K 2 receives the electronic

Control device 6 triggered by the thermostat 3 more

Switching signal for switching off the refrigerant compressor 2 at the time t _ß . The actual duration K _{2 of} the second

However, refrigeration cycle C _K 2 is less than the predefined

Duration K _v , so the actual refrigeration needs of the

Was cool volume 4 already met before the predefined duration K _v at time t is obtained. ₇ From this, the electronic control device 6 conclude that a

lower refrigeration requirement in the subsequent refrigeration cycle C _K 3

is required.

In order to meet the expected lower cooling requirements of the cooling volume 4 and this within the predefined

Duration K _{v of} the subsequent cooling cycle C _K 3, the third cooling cycle C _K 3 with a relation to the speed v _{4 of} the previous cooling cycle C _K 2 reduced speed v

started, which in the present embodiment of the

Start speed vi corresponds. In the third cooling cycle C _K 3 is the predefined duration K _v with the duration K _{3 of} the third

Cooling cycle C3 match, so that the refrigeration needs of Cooling is achieved within the volume 4 predefined duration K _v with the speed vi. In the third cooling cycle C _K 3, a particularly energy-saving operation of

Refrigerant compressor 2 reached.

The above-described control of the speed behavior of the refrigerant compressor 2 in the electronic

Control device 6 corresponds to the preset speed control, which is designed to allow over the entire operating time of the refrigerant compressor 2 as energy-optimized operation.

In selbstabtauenden simple refrigeration systems 1, the refrigeration system 1 undergoes a defrosting in predetermined, usually periodic, intervals. During the defrosting process, the evaporator 5a, for example, over it provided

Heating elements, heated to remove formed in the cooling volume 4 in the region of the evaporator 5a frost or ice layers. In this case, at least the refrigerant in the evaporator 5a is also heated. The defrost is triggered in a rest cycle C _R , so that the

Refrigerant compressor 2 is in the OFF state during defrosting. During defrosting is no

Switching signal triggered by the thermostat 3, which the

Refrigerant compressor 2 is set in the ON state. Only after the end of the defrosting the thermostat triggers the 3

Switching signal, so that the refrigerant compressor 2 is set by the electronic control device 6 of the refrigerant compressor 2 in the ON state.

The disadvantages of the prior art will be explained with reference to the speed behavior depicted in FIG. The first two cooling cycles C _K i, C _K 2 run, as previously described, after the default speed control. For simplicity, the two cooling cycles C _K i, C _K 2 are shown as such operating cycles in which the predefined duration K _{v of} the actual duration Ki, K ₂ corresponds and the refrigerant compressor 2 with the

Speed vi is operated. While on the second

Cooling cycle C _K 2 following third rest cycle C _R 3 is a Defrosting process, marked as DEFROST in the figure, triggered.

After the end of the defrosting operation, the thermostat 3 triggers the switching signal and the refrigerant compressor 2 is set in the ON state. Since the electronic control device 6 of the refrigerant compressor 2 of the simple refrigeration system 1 does not receive any control signal, which on a

the previous defrost cycle is concluded, the

Speed behavior of the refrigerant compressor 2 via the

Controlled default speed control and a third cooling cycle C _K 3 started. This starts with the start speed vi. As soon as the current time exceeds the predefined duration K _v , the speed v of the refrigerant compressor 2 is increased to the first increased speed v ₂ . Because the actual duration of the third

Cooling cycle C _K 3 also exceeds the limits of the predefined duration K _v i _/ K _v2 , K _v3 , the speed v increases stepwise to the increased speeds v ₃ , v ₄ and finally to a maximum speed v _max . Only after crossing the third

Limit value of the predefined duration K _v3 , the maximum speed v _{max is} reached in the present embodiment, in which the refrigerant compressor 2, the maximum cooling capacity

he brings. The increased cooling due to the defrosting cooling requirement of the cooling volume 4 of the refrigeration system 1 is therefore according to the prior art only after passing through the

Preset speed control achieved. As a result, on the one hand due to the defrosting increased temperature level in

Cooling volume only late with the full cooling capacity of the

Refrigerant compressor 2 pulled to a lower temperature level.

Another disadvantage manifests itself in the above-described determination of a starting speed v _s for the following

Cooling cycle C _K 4 in the third cooling cycle C _K3 . Because the

Maximum speed v _{max is} reached and the predefined duration K _v is significantly exceeded by the actual duration K _{3 of} the third cooling cycle C _K3 is, according to the

Default speed control the starting speed v _{s of} the fourth

Cooling cycle C _K 4 compared to the starting speed vi of the third Cooling cycle C _K 3 greatly increased. While the increase of the starting speed v _{s of} the next cooling cycle C _K due to an increased cooling demand in the cooling volume 4 usually leads to the most energy-optimized operation, the

Refrigerant compressor 2 operated in the previously described case with a too high for the cooling demand of the cooling volume 4 speed.

According to the invention is therefore in the electronic

Control device 6 of the refrigerant compressor 2 at least one comparison parameter P _v stored and overshoot or undershooting of the comparison parameter P _v is monitored by a current parameter value P _a to detect a previous defrosting. In the present embodiment shown in FIG. 5, the comparison parameter is a comparison duration P _v of FIG

Rest cycle C _R. Therefore, it is constantly monitored whether the current duration P _{a of} the current idle cycle C _R exceeds the comparison duration P _v . As soon as an exceeding of the comparison duration P _{v is} detected, a cooling cycle C _{K is not} started upon receipt of the switching signal triggered by the thermostat 3, but a special cooling cycle C _D different from the preset speed control is triggered. Since the speed behavior in the special cooling cycle C _D according to in the electronic control device 6 of

Refrigerated compressor 2 stored variables is controlled, it is possible the refrigerant compressor 2 immediately after the end of defrosting at a high speed v, in the present case already with the maximum speed v _max to operate. Thus, in direct consequence of the defrosting process, a high cooling capacity, in particular a maximum

Cooling capacity, available from the refrigerant compressor

set to pull down the temperature level of the cooling volume 4 as quickly as possible. As a result, on the one hand, the duration of the special cooling cycle C _D compared to the duration of the cooling cycle performed according to the default speed control C _K 3 (see FIG. 3) is lowered, on the other hand is thereby also the

Energy consumption lowered. It can for example be provided be that the speed v throughout the entire

Special cooling cycle C _{D is} kept constant, as the

solid speed characteristic in Fig. 5 represents. But it can also be provided that the refrigerant compressor 2 is operated during the special cooling cycle C _D with a speed behavior, as the dashed lines shown

Speed characteristic clarified. In this variant shown by way of example, the refrigerant compressor 2 is driven over the duration C _D i with the maximum speed v _max and subsequently increased over the duration C _D 2 with the third

Speed v ₄ is driven before the refrigerant compressor 2 has been accelerated to the maximum speed v _max. There are basically any progressive, degressive or

stepped waveforms of the speed characteristic during the special cooling C _D conceivable.

In the present embodiment, the starting speed v _{s of} the subsequent third cooling cycle C _K 3 is not by the

Influenced speed behavior during the special refrigeration cycle C _D, but the refrigerant compressor 2 in the subsequent third cooling cycle C _K 3 with the provided in the second cooling cycle C _K 2 speed vi is operated, since the special refrigeration cycle C _D when determining the starting speed V _s of the following third cooling cycle C _K 3 is not taken into account.

Figure 6 shows a second embodiment of the

inventive method. While in the previously discussed embodiment, the duration of the idle cycle C _R as

Comparison parameter P _v has been used in the present embodiment, an average load L _m of

Refrigerant compressor 2 in a start phase of the cooling cycle C _K as a comparison parameter P _v (not shown). In this case, the load L of the refrigerant compressor 2 by measuring the

electric current through the refrigerant compressor 2, in particular by the electrical current flowing through the electric drive unit of the refrigerant compressor 2, determined. After completion of the defrosting process, which in turn is referred to as DEFROST, a cooling cycle C _K controlled by means of the preset speed control starts. During the Start phase of the cooling cycle C _K , in the present example during the first 50 s after the refrigerant compressor 2 has been set to the ON state, the current load L is measured continuously and a current average load L _m calculated over the duration of the start phase of the cooling cycle C _K , This current average load L _m is then measured as currently measured parameter value P _a with that in the electronic control device 6 of

Refrigerant compressor 2 stored comparison parameter P _v compared. Since due to the heating of the refrigerant in the evaporator 5a during the defrosting process and / or due to the high refrigeration demand of the cooling volume 4, the currently measured average load L _m exceeds the stored comparison parameter P _v and the electronic control device 6 so concludes that a defrosting operation has taken place

Cooling cycle C _K interrupted after the end of the start phase and the special refrigeration cycle C _D started. Since the load L is only measurable during the cooling cycle C _K , the

Special cooling cycle C _D not directly due to the

Thermostat 3 triggered switching signal can be started, but only after the end of the start phase of the cooling cycle C _K.

However, the comparison with the speed behavior in Fig. 4 shows clearly that the refrigerant compressor 2 in the

present embodiment, promptly after defrosting a high cooling capacity, here even the maximum

Cooling capacity, provides, and therefore the

Refrigerator temperature faster to a lower

Temperature level is pulled.

FIG. 7 shows another aspect of the invention in which, due to the monitoring of the comparison parameter P _v , the electronic control device 6 of FIG

Refrigerant compressor 2 on a previous interruption of the power supply (as POWER BREAK in the drawing

characterized) is closed and due to the

Special cooling cycle C _{D is} triggered. In order to be able to infer a previous interruption of the power supply,

the electronic control device 6 monitors the

Power supply of the refrigerant compressor 2 and detects a power failure. This information alone is not sufficient to make a decision on the triggering of the special cooling cycle C _D , since the electronic

Control device 6 is no information about the duration of the interruption of the power supply. In the event of a brief power failure, the triggering of the special cooling cycle C _D does not make sense, since the cold room temperature only rises slightly during the interruption. However, if the power interruption lasts longer, the cooling volume 4 heats up and should be cooled down quickly by means of the special cooling cycle C _D.

Therefore, in the electronic control device 6 in addition to the interruption of the power supply, the further temperature T _{w is used} as currently measured parameter value P _a , the further temperature T _w , as shown in Figures 1 and 2, is measured by a temperature measuring device 7, either integral part of the electronic

Control device 6 of the refrigerant compressor 2 is or is arranged on the housing 8 of the refrigerant compressor 2. The comparison parameter P _v is this

Embodiment by a comparison temperature T _v , with which the currently measured additional temperature T _{w is} compared. About the comparison of the currently measured others

Temperature T _w with the reference temperature T _v can be checked how far the electronic control device 6 and the housing 8 of the refrigerant compressor 2 have cooled. During normal operation, in which

electronic control device 6 and housing 8 heat during the cooling cycle C _K takes place in the idle cycle C _R only a partial cooling until the next cooling cycle C _{K is} triggered. If the currently measured additional temperature T _w is thus below the comparison temperature T _v , then it can be concluded that no cooling cycle C _{K has} taken place over an above-average period of time. Due to the information that on the one hand a power failure

took place on the one hand and on the other hand over one

above-average period of time no cooling cycle C _K has taken place, the special cooling cycle C _D of the electronic control device 6 of the

Refrigerant compressor 2 triggered because it can be concluded on a long-lasting interruption of the power supply.

For the sake of clarity, the details of the

Special cooling cycle C _D referenced to the description of FIG. It goes without saying that several parameters can be monitored simultaneously, ie duration of the

Rest cycle C _R and / or average load L _m and / or others

Temperature T _w .

In alternative embodiments of the invention it can be provided that the further temperature T _w acts as the currently measured parameter value P _a and that it is in the

Comparison parameter P _v by a comparison temperature T _v and in the detection of a deviation of the currently measured further temperature T _w of the comparison temperature Jv a

Special cooling cycle C _{D is} triggered without a power failure was detected at the same time, so in other words can be concluded by monitoring the further temperature T _w on a previous defrosting and the corresponding special cooling cycle C _{D are} triggered.

Similarly, it is conceivable that a special cooling cycle C _{D is} triggered when it is at the currently measured

Parameter P _{a is} not around the further temperature is T _w and a previous power failure from the electronic

Control device 6 of the refrigerant compressor 2 has been detected. For example, it is also possible to deduce a longer interruption of the power supply if the currently measured parameter value P _a is the currently measured load L or the currently determined average load L _m and an overshoot or undershoot of the comparison parameter P _{v has been} detected ,

Basically, in each of the described

Variants be provided that the

Refrigerant compressor 2 is not constantly operated at the maximum speed v _max during the special cooling cycle C _D , but with a percentage of it, for example, 85% of the maximum speed v _max . Furthermore, it may be advantageous if the refrigerant compressor 2 during the

Special cooling cycle C _D does not fall below a predefined speed v _D , wherein the predefined speed v _{D is} again defined as a percentage of the maximum speed v _max , for example 75%. It is also advantageous if the refrigerant compressor 2 is operated immediately after the triggering of the special cooling cycle C _D with a high predefined speed v _D , wherein the predefined speed v _D

For example, 92% of the maximum speed v _max .

To better and more reliably detect the detection of special operating states, it can be provided in each of the previously described embodiments that the currently measured parameter values P _a are stored in the electronic control device 6 of the refrigerant compressor 2 over several operating cycles C. This is particularly advantageous if the value of the comparison parameter P _{v is} adapted on the basis of the stored parameter values P _s . Thus, the comparison parameter P _v, for example, depending on an extreme value P _E , ie a minimum or maximum, the stored parameter values P _{s are} varied or

for example as a function of a mean value P _M. Of the

Comparison parameter P _v can either directly the

Extreme value P _E or the mean value P _M. However, it is advantageous if a multiplicative deviation factor, for example the factor 1.5, in the interpretation of

Comparison parameter P _{v is} taken into account, ie the

Extreme value P _E or the mean value P _M multiplied by the deviation factor to set the value of the comparison parameter P _v . If the stored parameter values P _{s change} during operation, the comparison parameter P _v adapts automatically. REFERENCE LIST Refrigeration system

Refrigerant compressor

thermostat

cooling volume

Refrigerant line

5a evaporator

electronic control device of the refrigerant compressor 2

Temperature measuring device

Housing of the refrigerant compressor 2 8a Housing base

8b housing upper part

K _v predefined characteristic

K _a current parameter

v speed

C _R rest cycle

C _K refrigeration cycle

C operating cycle

Claims

1. Method for operating a variable speed

Refrigerant compressor (2) for cooling a

Cooling volume (4) of a refrigeration system (1), which comprises a thermostat (3) for direct or indirect monitoring of a temperature condition of the cooling volume (4) and wherein the refrigerant compressor (2) cyclically

is operated and a cooling cycle (C _K ) of the

Refrigerant compressor (2) starts when the

Refrigerant compressor (2) is set by a triggered by the thermostat (3) switching signal in an ON state and the cooling cycle (C _K ) ends when the

Refrigerant compressor (2) is set by a further switching signal triggered by the thermostat (3) in an OFF state,

wherein an operating cycle (C) comprises, in addition to the refrigeration cycle (C _K ), a rest cycle (C _R ) following the refrigeration cycle (C _K ),

and wherein the speed behavior of the

Refrigerant compressor (2) during a cooling cycle (C _K ) by means of a in an electronic

Controlled control device (6) of the refrigerant compressor (2) stored default speed control, characterized in that

- In the electronic control device (6) of the

Refrigerant compressor (2) at least one

Comparison parameter (P _v ) is stored and an over ^¬ or undershooting of the comparison parameter (P _v ) is monitored by a current measured parameter value (P _a ),

a special cooling cycle (C _D ) different from the preset speed control is triggered if the current measured parameter value (P _a ) exceeds or falls below the comparison parameter (P _v ), - where appropriate, an updated version by

Specified speed control controlled cooling cycle (C _K ) is interrupted by the special cooling cycle (C _D ).

A method according to claim 1, characterized in that it is in the at least one monitored

Comparison parameter (P _v ) or in one of the monitored comparison parameters (P _v ) by a load (L) of

Refrigerant compressor (2) in a start phase of a cooling cycle (C _K ) acts.

A method according to claim 2, characterized in that the load (L) as an average load (L _m ), averaged over the duration of the starting phase, wherein the duration of the starting phase is preferably between 10 s and 90 s, in particular between 40 s and 70 s , is monitored.

Method according to one of claims 1 to 3, characterized in that

it is the at least one monitored

Comparison parameter (P _v ) or in one of the monitored comparison parameters (P _v ) by a duration of the

Rest cycle (C _R ) is.

Method according to one of claims 1 to 4, characterized in that

one of the temperature of the cooling volume (4)

independent, further temperature (T _w ) is measured,

if the currently measured parameter value (P _a ) or one of the currently measured parameter values (P _a ) is the further temperature (T _w ),

- It is the at least one monitored

Comparison parameter (P _v ) or at one of the monitored comparison parameters (P _v ) by one

Comparative temperature (T _v ) is. Method according to one of claims 1 to 5, characterized in that

- The electronic control device (6) of

Refrigerant compressor (2) monitors whether a

Power supply of the electronic control device (6) has been interrupted,

- and the special cooling cycle (C _D ) is triggered when both exceeding or falling below the

Comparison parameter (P _v ) by the currently measured parameter value (P _a ) as well as a previous one

Interruption of the power supply are detected.

Method according to one of claims 1 to 6, characterized in that the at least one measured

current parameter value (P _a ) in the electronic

Control device (6) of the refrigerant compressor (2) over at least two operating cycles (C) as stored

Parameter value (P _s ) is stored.

A method according to claim 7, characterized in that in the electronic control device (6) of the

Refrigerant compressor (2) an extreme value (P _E ) of the stored parameter values (P _s ) is selected and the comparison parameter (P _v ) in dependence of

Extreme value (P _E ) is determined, preferably the

Maximum value (P _E ) corresponds.

Refrigerant compressor (2) an average value (P _M ) of the stored parameter values (P _s ) is calculated and the comparison parameter (P _v ) as a function of

Average value (P _M) is determined, preferably the

Mean value (P _M ) corresponds.

A method according to claim 8 or 9, characterized in that the comparison parameter (P _v ) by multiplying the extreme value (P _E ) or the average value (P _M ) with a Deviation factor is determined, the

11. The method according to any one of claims 1 to 10, characterized

characterized in that a starting speed (v _s ) of the

Refrigerant compressor (2) for the on

Special cooling cycle (C _c ) subsequent cooling cycle (C _K ) is set to a value stored in the electronic control device (6).

12. The method according to any one of claims 1 to 11, characterized

characterized in that the refrigerant compressor (2) during the special cooling cycle (C _D ) is operated such that the cooling volume (4) has a higher average

Cooling power is supplied as at one

comparable, according to the default speed control

controlled cooling cycle (C _K ).

13. The method according to any one of claims 1 to 12, characterized

characterized in that the refrigerant compressor (2) during the special cooling cycle (C _D ) is operated such that a defined speed (v _c ) is not exceeded until the end of the special cooling cycle (C _D ), wherein the defined speed (v _c ) at least 75 %, preferably at least 85%, particularly preferably at least 90%, in particular between 95% and 100%, of a maximum speed of the refrigerant compressor (2).

14. The method according to any one of claims 1 to 13, characterized

characterized in that the refrigerant compressor (2) at the beginning of the special cooling cycle (C _D ) is accelerated to a predefined speed (v _c ), wherein the at least one defined speed (v _c ) at least 70%, preferably more at least 80%, more preferably at least 90%, in particular between 95% and 100%, a maximum speed of the refrigerant compressor (2) is. Electronic control device (6) for controlling the cyclical operation of a variable speed

Refrigerant compressor (2),

wherein the electronic control device (6) is adapted to

- The refrigerant compressor (2) due to one of a thermostat (3) for direct or indirect

Monitoring a temperature condition of a

Cooling volume (4) of a refrigeration system (1) turn on switching signal to start a cooling cycle (C _k ) and a rest cycle (C _R ) to stop and

- Turn off the refrigerant compressor (2) due to one of the thermostat (3) triggered another switching signal again to end the cooling cycle (C _k ) and a rest cycle (C _R ) begin to ZU and

to regulate the speed behavior of the refrigerant compressor (2) during a refrigeration cycle (C _K ) by means of a preset speed control stored in the electronic control device (6),

characterized in that at least one comparison parameter (P _v ) in the

electronic control device (6) is stored and the electronic control device (6) is arranged to

- an overshoot or undershoot of the

Comparison parameters (P _v ) by a current

measured parameter value (P _a ) to detect,

to trigger a special cooling cycle (C _D ) other than the default speed control if the current measured parameter value (P _a ) is the

Comparison parameter (P _v ) exceeds or falls below,

- if applicable, a current one, by Default speed control regulated cooling cycle () to interrupt to start the special cooling cycle ().

Electronic control device (6) according to claim 15, characterized in that the electronic

Control means (6) is adapted to measure a load of the refrigerant compressor (2) as a current through the refrigerant compressor (2)

and that it is stored in the

Comparison parameter (P _v ) and the currently measured parameter value (P _a ) is loads.

Electronic control device (6) according to one of claims 15 or 16, characterized in that the electronic control device (6) is adapted to determine a duration of the rest cycle (C _R ) ZU

and that it is stored in the

Comparison parameter (P _v ) and the currently measured parameter value (P _a ) by the duration of a rest cycle (C _R ) acts.

Electronic control device (6) according to one of claims 15 to 17, characterized in that the electronic control device (6) with a

Temperature measuring device (7) for measuring a temperature of the cooling volume (4) independent, further temperature (T _w ) is connected,

and that it is stored in the

Comparison parameter (P _v ) by one

Comparison temperature (T _v ) and at the currently measured parameter value (P _a ) to the further temperature (T _w ) acts.

Electronic control device (6) according to claim 18, characterized in that the

Temperature measuring device (7) Part of the

electronic control device (6) of

Refrigerant compressor (2) is or that the Temperature measuring device (7) on a housing (8) of the refrigerant compressor (2) is arranged.

Electronic control device (6) according to one of claims 15 to 19, characterized in that the electronic control device (6) is arranged to

- to detect an interruption of the power supply and

- to trigger a special cooling cycle (C _D ), if both exceeding or falling below the

Interruption of the power supply was detected.

Comprising assembly

- A variable-speed refrigerant compressor (2) having an electric drive unit and a drivable by the electric drive unit piston-cylinder unit for compressing refrigerant;

- An electronic control device (6) according to any one of claims 15 to 20 for controlling the cyclical operation of the variable-speed refrigerant compressor (2) according to a method according to one of claims 1 to 14.