EP4039068A1

EP4039068A1 - System and method for operating a plasma jet configuration

Info

Publication number: EP4039068A1
Application number: EP20781039.1A
Authority: EP
Inventors: Rayk KOHLS; Klaus-Dieter Weltmann; Philipp Turski; Norbert Lembke; Torsten Gerling; Laura VILARDELL SCHOLTEN; Stefan Horn
Original assignee: Leibniz Institut fuer Plasmaforschung und Technologie eV
Current assignee: Leibniz Institut fuer Plasmaforschung und Technologie eV
Priority date: 2019-10-04
Filing date: 2020-10-05
Publication date: 2022-08-10
Also published as: US20240050760A1; JP2022550844A; CN114557137A; WO2021064242A1

Abstract

The invention relates to a system (1) for generating and controlling a non-thermal atmospheric pressure plasma, comprising: - a discharge space (10) into which a working gas can be introduced via a first opening (12), wherein a plasma (5) can be generated in the discharge space (10), wherein the discharge space (10) has a second opening (14), so that the plasma (5, 6) can exit from the discharge space (10) through this second opening (14) and - at least one high-voltage electrode (20) for generating an electromagnetic field for generating a plasma (5) in the discharge space (10). The plasma (5, 6) exiting through the second opening (14) is controlled by a throughflow controller (40) of the system (1), which throughflow controller (40) is designed to adjust a volume flow (60) of the working gas through the first opening (12) from a working gas source (50) into the discharge space (10). In this case, the throughflow controller (40) is further designed to assume at least a first state and a second state, wherein in the first state no working gas is supplied from the working gas source (50) to the discharge space (10), so that no plasma (5) exits from the second opening (14) even when there is a generated electromagnetic field in the discharge space (10), and wherein in the second state the working gas is supplied from the working gas source (50) to the discharge space (10), a plasma (5) is generated in the discharge space (10) and the plasma (5, 6) exits from the second opening (14).

Description

System and method for operating a plasma jet configuration

description

The invention relates to a system and a method for generating and controlling a non-thermal atmospheric pressure plasma.

Atmospheric pressure non-thermal plasmas are used, inter alia. used for medical purposes. This field of application is also known under the name of "plasma medicine".

Non-thermal atmospheric pressure plasma is also referred to below in the present application as plasma.

A plasma is to be understood as a gas with a proportion of free electrons, radicals, ions and neutral particles. Depending on the type of working gas, reactive species are generated by the plasma, for example reactive oxygen species such as ozone (O3). Reactive species can have an antimicrobial effect. Treatment with a plasma can therefore aid wound healing.

A plasma can be generated in a plasma jet arrangement, for example. In this case, a plasma can be generated in a discharge space in an electromagnetic field, which plasma is transported out of the device, in particular the discharge space, in the form of a plasma jet (plasma jet) with a gas stream.

Plasma jet arrangements are known in the prior art (Winter, J., Brandenburg, R., and Weltermann, K.-D. (2015), "Atmospheric pressure plasma jets: an overview of devices and new directions", Plasma Sources Sci Technol., 24, 064001). Such arrangements are particularly suitable for treating a small area.

The control of the plasma or the plasma jet of a plasma jet arrangement takes place via an electrical or electronic control of the respective applied electromagnetic field. For example, the electromagnetic field is brought to a standstill by means of the electrical or electronic control so that no more plasma is generated in the discharge space and thus no plasma emerges from the discharge space as a plasma jet. A new electromagnetic field is generated so that a plasma jet can be generated again. For a treatment of larger areas, for example for the treatment of wound healing in burn victims, individual plasma jet arrangements are only inadequately suitable, since they emit a focused plasma beam and therefore ensure punctual treatment.

Various solutions are known from the prior art in order to enable plasma treatment over a large area. Document US 2009/018 8626 A1 discloses an arrangement in which a multiplicity of electrodes are arranged in a common dielectric container. The document US 2004/012 38 03 A1 describes an arrangement in which a gas from a plurality of nozzles is continuously introduced into the space between two electrodes and a further gas can additionally be supplied to this space in pulses.

A multiplicity of individual plasma jets arranged next to one another is also referred to as plasma jet arrays in the context of this application. With a simultaneous operation of the individual plasma jet arrangements of the plasma jet array, the respective electromagnetic fields of the individual plasma jet arrangements would influence one another without a suitable shielding of the fields. Therefore, a great deal of effort is required for a suitable shielding, so that such an arrangement of a plasma jet array is very complex and costly to manufacture.

For simple and user-friendly use, plasma jet arrangements are of interest whose generated plasmas and / or emerging plasma jets are easy to control, for example can be easily switched on and / or switched off. Plasma jet arrays that are easy to control and are inexpensive to manufacture are also of interest.

These objects are achieved by the system according to claim 1 and the method according to claim 13. Advantageous refinements of the device are given in the subclaims. These and other embodiments are described below.

A first aspect of the invention relates to a system for generating and controlling a non-thermal atmospheric pressure plasma. The system has a discharge space into which a working gas can be introduced via a first opening. A plasma can be generated in the discharge space, in particular from the working gas that has been introduced. The discharge space has a second opening, so that the plasma can exit from the discharge space through this second opening.

The system has at least one high-voltage electrode for generating an electromagnetic field for generating a plasma, in particular for generating a plasma ignited from the working gas, in the discharge space. The plasma emerging through the second opening is controlled by a flow regulator of the system, which is designed to set a volume flow of the working gas through the first opening from a working gas source into the discharge space. The flow regulator is also designed to assume at least a first state and a second state. In the first state, no working gas is fed from the working gas source to the discharge space, so that no plasma emerges from the second opening even when an electromagnetic field is generated in the discharge space, in particular generated by the high-voltage electrode. In other words, this means that in the first state no working gas is fed from the working gas source to the discharge space, so that even with an existing electromagnetic field in the discharge space, no plasma emerges from the second opening. In the second state, the working gas is fed from the working gas source to the discharge space. A plasma is generated in the discharge space and the plasma emerges from the second opening. The plasma is generated in particular from the volume flow of the working gas supplied through the first opening directly by the electromagnetic field generated by the high-voltage electrode. The control of the volume flow by means of the flow regulator therefore allows a direct and immediate control of a plasma jet emerging at the second opening, and makes continuous generation of a primary plasma for igniting a secondary plasma superfluous.

This type of control represents a massive technical simplification of the system, especially since the generation and permanent maintenance of a primary plasma is not required in the discharge space.

The invention describes how a modulation of the volume flow of the working gas can advantageously be achieved with the aid of a flow regulator and thus allows a precise, i.e. time-resolved and spatially resolved (in the case of its large number of discharge spaces) metering of the volume flow, in particular by means of a flow regulator that can be regulated quickly. The modulation of the volume flow relates in particular not only to a simple "on" and "off" function, but also to a targeted control of a plasma jet emerging at the second opening via the volume flow of the working gas. The same applies to finely metered admixture to the working gas.

The advantages of the invention are particularly evident in a multijet arrangement, that is to say a system according to the invention with a large number of discharge spaces.

If electrical energy is used to operate / modulate a plasma jet, electromagnetic interference is always associated with it, on the one hand from the control of the high voltage source and on the other from the plasma itself correct operation and the setting of the desired / required plasma parameters is impaired. You cannot reduce this negative influence of electromagnetic interference without considerable technical effort, let alone eliminate it. The approach of the invention to regulate the supply and optionally the composition of the working gas in a targeted manner enables a simple and economically favorable effort. On the one hand, the technical complexity in the electronic control of the high voltage generation is reduced and, on the other hand, a fluid dynamic complexity is added. The overall complexity of the system is, however, reduced and further problems, especially with the arrays, are solved.

In the context of this application, a non-thermal plasma is also referred to as a low-temperature plasma or as a cold plasma. The plasma, which is transported out of the discharge space through the second opening by a gas flow, in particular the volume flow of the working gas, is also referred to as a plasma jet or plasma jet in the context of the document.

The discharge space can be delimited by a wall. The wall can delimit the first opening. According to the invention, the wall can delimit the second opening. The wall can be designed as a dielectric.

The discharge space includes, in particular, the volume in which the plasma can be generated.

When a voltage is applied, an electromagnetic field can be generated on the high-voltage electrode. The electromagnetic field generated is also referred to in this application as the existing electromagnetic field. With the help of the generated or existing electromagnetic field, a non-thermal atmospheric pressure plasma can be generated.

Plasmas can also be generated using lasers or ion beams. However, the parameters of the plasma such as temperature, leakage current or species generation are comparatively difficult to control and, compared to the principle of the invention, are associated with increased technical effort.

One embodiment provides that the high-voltage electrode is arranged within the discharge space.

The discharge space can be fluidically connected to a working gas source via the first opening. This means that working gas from the working gas source can be introduced into the discharge space through the first opening. A working gas can include or be one of the following gases: hydrogen, argon, helium, nitrogen, oxygen, neon, krypton or carbon dioxide. The working gas can be a gas mixture which has at least one of the following gases: hydrogen, argon, helium, nitrogen, oxygen, neon, krypton or carbon dioxide. In particular, the working gas can comprise argon or be argon.

The flow regulator can assume at least a first and a second state. In the first state of the flow regulator, it is set up so that no working gas is introduced into the discharge space. In other words, this means that a gas supply (in particular the supply of the working gas) into the discharge space is interrupted in the second state. No working gas flows from the first opening through the discharge space in the direction of the second opening. Furthermore, no working gas flows from the first opening in the direction of the second opening and out of the discharge space from the latter. There is no volume flow of the working gas in the discharge space. No plasma is transported out of the second opening in the form of a plasma jet with the volume flow.

If no working gas is introduced into the discharge space, so that no plasma jet emerges from the discharge space, no working gas either emerges from the discharge space. The consumption of the working gas is thus advantageously reduced compared to a device of the prior art in which working gas flows continuously through the discharge space and out of the discharge space.

The system can be set up in such a way that no plasma is generated in the discharge space in the first state.

In the second state of the flow regulator, it is designed so that working gas is introduced into the discharge space. In particular, working gas is introduced in such a way that it flows through the first opening into the discharge space and flows through the discharge space in the direction of the second opening. In particular, the working gas that has been introduced flows from the first opening in the direction of the second opening and out of the latter out of the discharge space.

Due to the volume flow of the working gas, the plasma generated in the discharge space emerges as a plasma jet through the second opening from the discharge space.

By controlling the flow regulator, it can be set whether or not the plasma emerges from the discharge space as a plasma jet. In other words, this meant that the system according to the invention achieves fluid-dynamic control of the ejection of the plasma from the discharge space. This means that the plasma jet can be controlled in a fluid dynamic manner. In this way, the plasma jet can be controlled in a simple manner without a control or regulation of the electromagnetic field, In particular, it can be controlled whether a plasma jet emerges from the discharge space. The complexity of the electrics and / or electronics is advantageously reduced. The overall complexity of the system is reduced.

According to one embodiment, the system has at least one ground electrode. The at least one high-voltage electrode and the at least one ground electrode can be designed to generate an electromagnetic field for generating a plasma in the discharge space.

This ensures, in particular, that the plasma generation is independent of a distance from a surface to be treated, which then otherwise acts as a counter electrode and significantly influences the properties of the plasma.

In one embodiment, the system has at least one high-voltage electrode and at least one ground electrode for generating an electromagnetic field for generating a plasma in the discharge space.

The plasma emerging through the second opening is controlled by a flow regulator of the system, which is designed to set a volume flow of the working gas through the first opening from a working gas source into the discharge space. The flow regulator is also designed to assume at least a first state and a second state. In the first state, no working gas is fed from the working gas source to the discharge space, so that no plasma emerges from the second opening even when the electromagnetic field is generated in the discharge space, in particular by the ground electrode and the high-voltage electrode. In other words, this means that in the first state no working gas is fed from the working gas source to the discharge space, so that even with an existing electromagnetic field in the discharge space, no plasma emerges from the second opening. In the second state, the working gas is fed from the working gas source to the discharge space. A plasma is generated in the discharge space and the plasma emerges from the second opening.

When a voltage is applied, an electromagnetic field can be generated between the high-voltage electrode and the ground electrode. The electromagnetic field generated is also referred to in this application as the existing electromagnetic field. With the help of the generated or existing electromagnetic field, a non-thermal atmospheric pressure plasma can be generated.

In one embodiment, a ground electrode is arranged on the discharge space. One advantage of an embodiment that has a ground electrode is that the electromagnetic field is generated and / or adjusted more precisely. Characteristics of the generated plasma can thus also be set more precisely.

In one embodiment, the system is set up to generate a modulation of the plasma by a corresponding modulation of the volume flow of the working gas, in particular exclusively by a corresponding modulation of the volume flow of the working gas and in particular not by a modulation of the electromagnetic field, in particular with the system for this purpose is set up to generate only a continuous electromagnetic field in the discharge space. In one embodiment, the system is designed to generate only a continuous electromagnetic field in the discharge space, in particular during the modulation of the plasma.

A modulation of the plasma means, in particular, a change in the plasma jet. The modulation of the plasma can mean that the plasma is transferred from a status in which it emerges from the discharge space, in particular as a plasma jet, into another status in which it does not emerge from the discharge space, i.e. H. no more plasma jet emerges from the discharge space. The modulation of the plasma can be such that a distance by which the plasma jet emerges from the discharge space through the second opening is changed. The distance can be shortened, especially down to a minimal distance. If the minimum distance is not reached, no plasma emerges from the discharge space. Alternatively, it is provided that the distance can be increased.

One embodiment is characterized in that the modulation of the plasma is generated by a corresponding modulation of the working gas volume flow. If no working gas volume flow is generated, no plasma jet emerges from the discharge space. When a volume flow of the working gas is present, a plasma jet can exit through the second opening of the discharge space.

The working gas volume flow can be pulsed. A pulsed working gas volume flow is a non-continuous volume flow that changes in amount over time.

The plasma can be modulated by modulating the working gas volume flow. Furthermore, the consumption of the working gas can be controlled. In one embodiment, the consumption of the working gas is regulated. An embodiment according to the invention provides that a duration and / or an effect of a leakage current is controlled. A leakage current can occur when the plasma (plasma jet) touches a surface. If no plasma jet emerges from the discharge space, there is no leakage current on a surface. A continuous electromagnetic field is to be understood in particular as an electromagnetic field that is switched on continuously and also continues to exist when no working gas volume flow is flowing through the discharge space. In this sense, the term "continuous" is also to be regarded as permanent or constant (apart from the implicit time dependence of an electromagnetic field due to the alternation of the electrical and magnetic components of the field).

In one embodiment, the electromagnetic field is a continuous electromagnetic field. In particular, the electromagnetic field is continuous with respect to the amplitude of the field strength. In one embodiment, the electromagnetic field is constant over time.

One embodiment is characterized in that the continuous electromagnetic field is generated with the aid of a direct voltage. According to the invention, the applied direct voltage is not modulated in order to achieve a modulation of the plasma.

In an alternative embodiment, the electromagnetic field is generated with the aid of an alternating voltage. In order to modulate the plasma, the applied alternating voltage is not modulated.

The electromagnetic field is only used to generate the plasma. According to the invention, the electromagnetic field is not used to modulate the plasma. In particular, the electromagnetic field is not modulated in order to modulate the plasma. In particular, the electromagnetic field is not modulated in order to generate an exit of the plasma (plasma jet) from the discharge space and / or in order to stop an exit of the plasma from the discharge space. The exit of the plasma jet from the discharge space can be controlled by the working gas volume flow.

According to a further embodiment, the flow regulator is designed to modulate the volume flow of the working gas.

In one embodiment, the working gas volume flow can be adjusted with the aid of the flow regulator.

The flow regulator can be designed as a discrete directional valve. A discrete directional control valve can switch discretely between a first state (closed) and a second state (open).

In an alternative embodiment, the flow regulator is a proportional valve. A proportional valve can achieve continuous transitions of a valve opening. I. E. the Proportional valve mediates a partial opening and / or closing, so that a passage of the working gas can be precisely metered.

The working gas volume flow can be modulated by controlling the flow regulator. For example, by transferring the flow regulator from its first state to its second state, a working gas volume flow can arise in the discharge space, with which the plasma can exit the discharge space as a plasma jet. An alternative modulation can be created by transferring the flow regulator from its second state to its first state. By transferring the flow regulator from its second state to its first state, a working gas volume flow in the discharge space can be ended, so that the plasma no longer exits the discharge space.

This means that the working gas volume flow can be controlled with the aid of the flow regulator. The exit of the plasma from the discharge space can be controlled via the working gas volume flow. The flow regulator can provide fluid dynamic control of the plasma. In particular, the plasma can be modulated without the electromagnetic field being controlled. The exit of the plasma from the discharge space is therefore possible in a simple manner without the applied electromagnetic field being changed.

By precisely metering the working gas, the distance by which the plasma jet emerges from the discharge space can be precisely set and / or changed.

In one embodiment, the flow regulator is electronically controlled. In one embodiment, the flow regulator is electrically controlled. This means that a fluid-dynamic control of the plasma is provided by means of an electrical or electronic control of the flow regulator.

One embodiment is characterized in that the flow regulator has a short switching time. A short switching time means that the flow controller can switch quickly between the individual states.

According to one embodiment, the system is designed to transfer the flow regulator from the first state to the second state, so that when an electromagnetic field is generated in the discharge space, the plasma is generated in the discharge space and exits the discharge space through the second opening. In one embodiment, the system is designed to transfer the flow regulator from the second state to the first state, so that when an electromagnetic field is generated in the discharge space, no plasma emerges from the discharge space. One embodiment of the system is designed to switch the flow regulator from the first state to the second To transfer state and to transfer the flow controller from the second state to the first state.

In other words, this means that the flow regulator is designed to switch on the plasma jet, i. H. Plasma emerges from the discharge space as a plasma jet after no plasma has previously emerged from the discharge space. In one embodiment, the system is set up to switch off the plasma jet. This means that no plasma jet emerges from the discharge space after a plasma jet has previously emerged from the discharge space.

One embodiment is characterized in that the flow regulator has an active actuator which is designed to assume at least the first or the second state.

The active actuator is, for example, a valve, in particular a solenoid valve. The active actuator can be controlled electrically.

An active actuator can be designed as a discrete directional valve that assumes the first or the second state. In one embodiment, the active actuator is designed as a proportional valve.

The active actuator can be a piezo valve. With the help of a piezo valve, the flow of the working gas can be dosed quickly and precisely. A piezo valve consumes little energy. This is particularly advantageous when the system is used as a hand-held device, since in this case a battery lasts longer and fewer battery changes or charging cycles are necessary. This increases the convenience and the possible uses of the system, in particular the possibility of mobile use of the system.

In one embodiment, the working gas source delivers working gas constantly (evenly over time). With the help of the active actuator, a working gas volume flow pulsed over time can be introduced into the discharge space.

In one embodiment, the flow regulator has a passive actuator which is designed to assume at least the first or the second state, the passive actuator being able to be transferred from the first state to the second state in particular by the volume flow of the working gas.

The passive actuator can be a flutter valve or a check valve.

The active and / or the passive actuator can be a microvalve. A microvalve advantageously allows the flow regulator to be installed in a space-saving manner. This means that the space required by the system can be kept small. This is particularly advantageous when the system is used as a hand-held device. According to a further embodiment, the system has a working gas source which has the flow regulator.

The working gas source can, for example, have a control element, with the aid of which it can be set whether working gas flows out of the working source. In one embodiment, the outflow of the working gas, and thus the working gas volume flow, is metered with the aid of a control element. In one embodiment, the system is set up so that a pulsed working gas volume flow emerges from the working gas source and flows into the discharge space.

In one embodiment, the system has an automatic control unit which is designed to control the flow regulator. With the help of the automatic control unit, the flow regulator can be automatically set to the first state or the second state. Furthermore, in one embodiment, the automatic control unit is designed to transfer the flow regulator to the second state for a selected period of time, so that a period of time can be set over which the working gas is introduced into the discharge space.

The automatic control unit can be used to control whether working gas can flow into the discharge space. In one embodiment, the automatic control unit controls the working gas volume flow.

In one embodiment, the automatic control unit has a microcontroller and a high-voltage coil.

The automatic control unit can control that the flow regulator is in the second state for a selected period of time. This means that the automatic control unit can control that there is a working gas volume flow in the discharge space for the selected period.

In one embodiment, the automatic control unit controls switching on of the plasma jet. The automatic control unit can control how long the plasma jet is switched on. Furthermore, in one embodiment, the automatic control unit controls the distance by which the plasma jet emerges from the discharge space through the second opening. In one embodiment, the automatic control unit controls switching off the plasma jet. The automatic control unit can be set up to switch off the plasma jet for a period of time after the plasma jet was switched on for a different period of time. In one embodiment, the automatic control unit is set up to switch on the plasma jet for a selected period of time after the plasma jet was previously switched off for another selected period of time. One embodiment of the automatic control unit is designed to precisely meter the working gas that flows into the discharge space, for example by controlling a proportional valve.

The automatic control unit can be programmable.

One advantage of the embodiment is that it is automatically controlled when and for how long (i.e. over what period of time) a plasma jet emerges from the discharge space. In this way, for example, a treatment duration can be controlled automatically by means of the plasma jet.

In one embodiment, the automatic control unit is set up to regulate the working gas volume flow. In one embodiment, the system has a feedback mechanism for the regulation.

With the aid of the feedback mechanism, a fluctuation (deviation from a control value) in the plasma is advantageously automatically detected and counteracted by modulating the working gas volume flow, for example. The fluctuation is balanced out so that a uniform plasma jet emerges over time.

According to one embodiment, the system has a mixing arrangement which is designed to mix a further gas with the working gas so that the resulting gas mixture can be introduced into the discharge space. In particular, the system is set up so that the flow regulator has the mixing arrangement.

In one embodiment, the mixing arrangement is set up to mix a multiplicity of gases with the working gas. One embodiment provides that a gas mixture is mixed with the working gas, in particular mixed in the mixing arrangement.

The further gas is in particular one of the following gases: hydrogen, oxygen, nitrogen, water vapor, argon, helium, neon, krypton or carbon dioxide. The added gas mixture has in particular one of the following gases: hydrogen, oxygen, nitrogen, water vapor, argon, helium, neon, krypton or carbon dioxide. The admixed gas mixture can be air, in particular ambient air. In one embodiment, the admixed gas mixture is a humidified gas. In particular, the admixed gas mixture can contain water vapor, as well as at least one of the following gases: hydrogen, oxygen, nitrogen, water vapor, argon, helium, neon, krypton or carbon dioxide.

In this way, a gas mixture different from the working gas can be introduced into the discharge space and other reactive species can arise there. In one embodiment, the system is set up to mix the further gas with the working gas for a selected period. The composition of the gas or gas mixture which is introduced into the discharge space can thus be adjusted in a time-resolved manner. In one embodiment, the composition of the gas or gas mixture which is introduced into the discharge space can be controlled in a time-resolved manner.

In one embodiment, the system is designed to generate a capacitively coupled plasma. One embodiment is characterized in that the system is designed to generate an inductively coupled plasma. In one embodiment, the system is designed to generate a microwave-induced plasma. In an alternative embodiment, the system is designed to generate a plasma by means of a dielectrically impeded discharge.

In a further embodiment, the system has a plurality of discharge spaces, each discharge space having a respective first opening through which a working gas can be introduced into the respective discharge space, each discharge space having an associated second opening through which the plasma from the respective discharge space can emerge. Each discharge space is assigned at least one high-voltage electrode for generating an electromagnetic field for generating a plasma in the respective discharge space, so that a plasma can be generated in each discharge space independently of the other discharge spaces. The plasma exiting through the assigned second opening is controlled by a flow controller of the system assigned to the respective discharge space, each flow controller being designed to set a volume flow of the working gas through the respective first opening of the respective discharge space from a working gas source into the respective discharge space. Furthermore, the respective flow regulator is designed to assume at least a first state and a second state. In the first state, no working gas is fed from the working gas source to the respective discharge space, so that no plasma emerges from the associated second opening in the respective discharge space even when an electromagnetic field is generated in the respective discharge space. In the second state, the working gas is supplied from the working gas source to the respective discharge space of the plurality of discharge spaces and a plasma is generated there, and the plasma emerges from the respective second opening.

In a further embodiment, the system has a multiplicity of discharge spaces, each discharge space of the multiplicity of discharge spaces having a respective first opening through which a working gas can be introduced into the respective discharge space of the multiplicity of discharge spaces. Each discharge space of the plurality of discharge spaces has an associated second opening through which the plasma can exit from the respective discharge space of the plurality of discharge spaces. Furthermore, each discharge space of the plurality of discharge spaces is assigned at least one high-voltage electrode for generating an electromagnetic field for generating a plasma in the respective discharge space of the plurality of discharge spaces. In each discharge space of the multiplicity of discharge spaces, a plasma can be generated independently of the other discharge spaces of the multiplicity of discharge spaces, the plasma exiting through the associated second opening being controlled by a flow regulator of a multiplicity of flow regulators of the system associated with the respective discharge space of the multiplicity of discharge spaces . Each flow regulator of the plurality of flow regulators is designed to set a volume flow of the working gas through the respective first opening of the respective discharge chamber of the plurality of discharge chambers from a working gas source into the respective discharge chamber of the plurality of discharge chambers, the respective flow regulator of the plurality of flow regulators also being designed to do so is to assume at least a first state and a second state. In the first state, no working gas is fed from the working gas source to the respective discharge space of the multiplicity of discharge spaces, so that in the respective discharge space of the multiplicity of discharge spaces, even when an electromagnetic field is generated in the respective discharge space of the multiplicity of discharge spaces, no plasma escapes from the associated second opening. In the second state, the working gas is supplied from the working gas source to the respective discharge space of the plurality of discharge spaces and a plasma is generated there, and the plasma emerges from the respective second opening.

Each discharge space (the plurality of discharge spaces) is assigned at least one high-voltage electrode for generating an electromagnetic field for generating a plasma in the respective discharge space (the plurality of discharge spaces), in particular with at least one high-voltage electrode in each discharge space (the plurality of discharge spaces) for generating a electromagnetic field for generating a plasma is arranged in the respective discharge space (the plurality of discharge spaces), so that a plasma can be generated in each discharge space (the plurality of discharge spaces) independently of the other discharge spaces (the plurality of discharge spaces).

The high-voltage electrodes can in particular be short-circuited with one another. In one embodiment, the discharge spaces of the plurality of discharge spaces are formed identically. In an alternative embodiment, at least one discharge space of the plurality of discharge spaces differs from the other discharge spaces.

One advantage of a system with a large number of discharge spaces is that a larger area, for example a surface of an object, can be treated with plasma without the system and / or the object to be treated having to be moved.

Such a system can be used for a large surface treatment, in particular for a thermally sensitive surface treatment.

Each flow regulator of the multitude of flow regulators can be controlled electrically or electronically. By controlling an assigned flow regulator, the working gas volume flow in the respective discharge space is controlled, and thus the plasma, in particular whether or not the plasma emerges from the respective discharge space in the form of a plasma jet. This means that the electrical or electronic control of the respective flow regulator results in a fluid dynamic control of the plasma, in particular the plasma jet.

This reduces the technical complexity of controlling the plasma in a system that has a large number of discharge spaces. Perfect operation of the system is made possible in a simple manner.

One embodiment is characterized in that at least one ground electrode is assigned to each discharge space. In one embodiment, the at least one high-voltage electrode and the at least one ground electrode are set up to generate an electromagnetic field for generating a plasma in the respective discharge space. The system is designed in particular to ignite the plasma, in particular in the volume flow of the working gas, directly by the electromagnetic field of the high-voltage electrode.

In one embodiment, the system has a multiplicity of discharge spaces, each discharge space of the multiplicity of discharge spaces having a respective first opening through which a working gas can be introduced into the respective discharge space of the multiplicity of discharge spaces. Each discharge space of the multiplicity of discharge spaces has an associated second opening through which the plasma can exit from the respective discharge space of the multiplicity of discharge spaces. Furthermore, each discharge space of the plurality of discharge spaces is assigned at least one high-voltage electrode and at least one ground electrode for generating an electromagnetic field for generating a plasma in the respective discharge space of the plurality of discharge spaces. In each discharge space the plurality of discharge spaces is independent of a plasma can be generated in the other discharge spaces of the multiplicity of discharge spaces, the plasma exiting through the associated second opening being controlled by a flow controller of a multiplicity of flow controllers of the system associated with the respective discharge space of the multiplicity of discharge spaces. Each flow regulator of the plurality of flow regulators is designed to set a volume flow of the working gas through the respective first opening of the respective discharge chamber of the plurality of discharge chambers from a working gas source into the respective discharge chamber of the plurality of discharge chambers, the respective flow regulator of the plurality of flow regulators also being designed to do so is to assume at least a first state and a second state. In the first state, no working gas is fed from the working gas source to the respective discharge space of the multiplicity of discharge spaces, so that in the respective discharge space of the multiplicity of discharge spaces, even when an electromagnetic field is generated in the respective discharge space of the multiplicity of discharge spaces, no plasma escapes from the associated second opening. In the second state, the working gas is supplied from the working gas source to the respective discharge space of the plurality of discharge spaces and a plasma is generated there, and the plasma emerges from the respective second opening.

Each discharge space (the multiplicity of discharge spaces) is assigned at least one high-voltage electrode and at least one ground electrode for generating an electromagnetic field for generating a plasma in the respective discharge space (the multiplicity of discharge spaces), in particular with at least one at each discharge space (the multiplicity of discharge spaces) High-voltage electrode and at least one ground electrode for generating an electromagnetic field for generating a plasma is arranged in the respective discharge space (the plurality of discharge spaces), so that in each discharge space (the plurality of discharge spaces) independently of the other discharge spaces (the plurality of discharge spaces) a plasma can be generated.

In one embodiment the system has an automatic control system. The automatic control system is designed to control the plurality of flow regulators of the system independently of one another, so that the flow regulators can assume at least the first state or the second state independently of one another, so that plasma is only generated in a selected discharge space and only from the second Opening of the selected discharge space exits. The automatic control system can control each flow regulator of the multitude of flow regulators individually. This means that each flow regulator of the large number of flow regulators can be controlled independently of the other flow regulators.

In one embodiment, the automatic control system is designed to individually regulate each flow regulator of the plurality of flow regulators, so that each flow regulator of the plurality of flow regulators can be regulated independently of the other flow regulators.

In one embodiment, the automatic control system is set up in such a way that each flow regulator of the plurality of flow regulators is controlled in such a way that the plasma jet of the respective associated discharge space shows a selected time pattern, i. H. a selected sequence of phases in which a plasma jet emerges from the respective assigned discharge space and other phases in which no plasma jet emerges.

According to one embodiment, the automatic control system is designed to control the flow regulators of the plurality of flow regulators of the system independently of one another, so that a selected flow regulator of the plurality of flow regulators assumes the second state for a first period and all other flow regulators of the plurality of flow regulators assumes the first state and after the first period of time the selected flow controller of the plurality of flow controllers assumes the first state and another selected flow controller of the plurality of flow controllers assumes the second state for a second period of time, the first and the second period of time following one another or at times overlapping.

The automatic control system can control from which selected discharge space a plasma jet emerges. In particular, the automatic control system is designed so that a plasma jet emerges from a selected discharge space of the plurality of discharge spaces at any point in time.

In one embodiment, the automatic control system is set up to control the flow regulators of the plurality of flow regulators in such a way that the first time period and the second time period follow one another without interruption. In other words, this means that in one embodiment the automatic control system is set up to control the flow regulators of the plurality of flow regulators in such a way that a plasma jet emerges from exactly one discharge space of the multiplicity of discharge spaces at any point in time.

In an alternative embodiment, the automatic control system is set up to control the flow regulators of the plurality of flow regulators in such a way that the first Period of time and the second period of time overlap temporarily, in particular the first period of time and the second period of time not being completely superimposed. This means that, in one embodiment, the system is set up so that in the overlapping period of the first and the second period, a plasma jet emerges from the two discharge spaces (to which the flow regulator and the other flow regulator are assigned). One embodiment provides that the overlap period is short, in particular shorter than 1 s.

In one embodiment, the system is designed so that each discharge space of the plurality of discharge spaces can be or is connected to a common working gas source.

The same reactive species can arise in each discharge space.

This embodiment is particularly advantageous if the system is used for a large-area treatment with a plasma, with the same species acting over the entire area.

According to a further embodiment, at least one flow regulator of the plurality of flow regulators has a mixing arrangement with which a further gas is mixed with the working gas so that a resulting gas mixture can be introduced into the respective discharge space of the plurality of discharge spaces. This means that spatially resolved, e.g. B. in a discharge space, which is arranged at a selected position in relation to the other discharge spaces of the system, a further gas can be added to the working gas in a metered manner. This can be spatially resolved, e.g. B. in a selected local area, the effectiveness of the plasma can be adapted to specific requirements, for example when treating large wound areas.

In a further embodiment, the system is designed so that at least one discharge space of the plurality of discharge spaces can be or is connected to its own working gas source.

In the at least one discharge space, a reactive species can arise that differs from a reactive species that can arise in the other discharge spaces.

This embodiment is particularly advantageous when the system is used for a large-area treatment with a plasma, the area having at least one partial area on which at least one species is to act that differs from a reactive species that arises in the other discharge spaces . In other words, this means that the effectiveness of the plasma can be adapted to requirements for the treatment of the at least one partial area. One embodiment is characterized in that the second openings of the plurality of discharge spaces point in the same direction.

In particular, the surface normals of the second openings point in the same direction.

One advantage of such an arrangement is that plasma jets can be directed onto a surface with such a system.

According to a further embodiment, the second openings of the plurality of discharge spaces are positioned or positionable in such a way that they face a central region.

In particular, the surface normals of the second openings face a central area.

In one embodiment, the second openings of the plurality of discharge spaces are oriented in the direction of a common volume.

With such a system, plasma jets can be directed onto the surface of an object from a variety of directions.

In one embodiment, the second openings of the plurality of discharge spaces are arranged in a common plane.

In one embodiment, the second openings of the plurality of discharge spaces are arranged in a common plane, the second openings of the plurality of discharge spaces covering an area of at least 10 cm ² , in particular at least 50 cm ² , in particular at least 100 cm ² .

According to a further embodiment, the system has at least 2 discharge spaces, in particular at least 5 discharge spaces, in particular at least 10 discharge spaces, in particular at least 20 discharge spaces.

According to a further embodiment of the invention, the at least one is

Flow regulator continuously adjustable so that the volume flow through each discharge space can be continuously and individually adjusted.

According to a further embodiment of the invention, the at least one is

Flow regulator a proportional valve.

According to a further embodiment of the invention, the system is set up to modulate the volume flow of the working gas in each discharge space by means of the flow regulator, the modulation of the volume flow having more than two modulation states, in particular the modulation of the volume flow being continuously adjustable. According to a further embodiment of the invention, each flow regulator is set up to have a control time between 0.1 ms and 1 s, so that the volume flow can be modulated with a corresponding time resolution.

According to a further embodiment of the invention, the system has at least one associated sensor for each discharge space which detects a plasma parameter and which is set up to output a sensor signal indicative of the plasma parameter, the system being set up to control the at least one flow controller based on the sensor signal to be regulated in such a way that a plasma parameter to be achieved is set for the respectively assigned discharge space.

According to a further embodiment of the invention, the system has exactly one high-voltage electrode and no more than two ground electrodes per discharge space.

According to a further embodiment of the invention, the system is set up to generate a capacitively-coupled, an inductively-coupled and / or a microwave-induced plasma in the volume flow of the working gas supplied through the first opening.

According to a further embodiment of the invention, each discharge space has exactly two openings - the first and the second opening. Another aspect of the invention relates to a method for generating and controlling a non-thermal atmospheric pressure plasma using a system according to the invention. The process has the following steps:

- Generation of an electromagnetic field in the discharge space,

- Setting the flow regulator in a first state or a second state, wherein in the first state no working gas is supplied from the working gas source to the discharge space, so that in the discharge space even when an electromagnetic field is generated in the discharge space, no plasma escapes from the discharge space, and in the second state the working gas from the working gas source is supplied to the discharge space, a plasma is generated in the discharge space and the plasma emerges from the second opening.

In one embodiment, the plasma is regulated.

One embodiment of the method has the following steps: Generation of an electromagnetic field in each discharge space of the plurality

Discharge spaces,

- Setting each flow regulator of the plurality of flow regulators in a first state or a second state, wherein in the first state no working gas from the working gas source is in the respective discharge space of the multiplicity of discharge spaces is supplied so that in the respective discharge space of the plurality of discharge spaces, even when the electromagnetic field is generated in the respective discharge space of the multiplicity of discharge spaces, no plasma escapes from the respective discharge space, and in the second state the working gas from the working gas source is supplied to the respective discharge space of the multiplicity of discharge spaces is, a plasma is generated in the respective discharge space of the plurality of discharge spaces and the plasma emerges from the associated second opening.

In one embodiment, the method is characterized in that the volume flow of the working gas that is supplied to the discharge space or a selected discharge space of the plurality of discharge spaces is modulated in order to generate a modulation of the plasma, while a continuous electromagnetic field in the discharge space or the selected Discharge space of the plurality of discharge spaces is generated.

According to one embodiment, a flow regulator of the plurality of flow regulators is controlled so that it assumes the second state for a first period of time and all other flow regulators of the plurality of flow regulators are controlled in such a way that they assume the first state and, after the first period of time, the flow regulator of the A plurality of flow regulators is transferred to the first state and another flow regulator of the plurality of flow regulators is transferred to the second state following the first period of time or overlapping with the first period and occupies this for a second period of time, while the remaining other flow regulators of the plurality continue Flow regulators remain in the first state.

This means that a plasma jet emerges from a selected discharge space of the multiplicity of discharge spaces, while no plasma jet emerges from the other discharge spaces.

The plurality of flow regulators can be controlled in such a way that different selected flow regulators pass one after the other from the respective first state to the respective second state. This means that plasma jets can emerge one after the other from different selected discharge spaces, in particular a plasma jet emerging from only one selected discharge space of the plurality of discharge spaces at the same time.

According to one embodiment, the automatic control system controls the plurality of flow regulators, so that each flow regulator of the plurality of flow regulators is independent of the other flow regulators of the plurality of flow regulators in one selected sequence changes between the first state and the second state and / or between the second state and the first state.

Each flow regulator of the plurality of flow regulators can be controlled independently of the other flow regulators. In particular, each flow regulator of the plurality can be controlled independently of the other flow regulators in such a way that a plasma jet emerges from the respective discharge space (second state) or no plasma jet emerges (first state). The automatic control system can control the large number of flow regulators in such a way that at any point in time a plasma jet emerges from only one selected discharge space of the large number of discharge spaces.

A plasma jet can be controlled in a simple manner by means of a system according to the invention. One embodiment of the system is set up so that a large number of plasma jets are controlled and / or regulated in a coordinated manner. The electrical and / or electronic complexity of the system is advantageously reduced compared to a system of the prior art. The overall complexity of the system according to the invention is reduced. This reduces the production costs of such a system and is therefore economically advantageous.

In the following, embodiments as well as features and advantages of the invention are explained with reference to the figures. Show it:

1 shows a schematic representation of an embodiment of a system according to the invention with a discharge space in which the flow regulator assumes the first state,

FIG. 2 shows the system from FIG. 1, in which the flow regulator assumes the second state,

3 shows a schematic representation of a system according to the invention

Flow regulator in the second state,

4 shows a schematic representation of a system in which the flow regulator assumes the first state,

5 shows a schematic representation of an embodiment of a system according to the invention in which the flow regulator is shown in the first state,

Fig. 6 is a schematic representation of a system according to the invention in which the

Flow controller assumes the first state, 7a) -7f) different views of a hand-held device of a system with a large number of discharge spaces,

8 shows a schematic representation of an embodiment of a system according to the invention with three discharge spaces, the associated flow regulators of which assume the first state,

FIG. 9 shows a schematic representation of the system from FIG. 8, with a

Flow controller assumes the second state,

10 shows a schematic representation of a system according to the invention with two discharge chambers, a flow regulator being in the first state and a flow regulator being in the second state, the system having a working gas source,

11 shows a schematic representation of a system with two discharge chambers, a flow regulator being in the first state and a flow regulator being in the second state, the system having two working gas sources,

12 shows a schematic representation of a system according to the invention with a mixing arrangement and two discharge spaces, a flow regulator being in the first state and a flow regulator being in the second state,

13 shows a front view of a system with a plurality of discharge spaces, the second openings of which face a central area,

14 shows a cross section of the system from FIG. 13, and

15 shows a front view of a system with a plurality of discharge spaces, the second openings of which face a central area.

Fiqurenbeschreibunq

Figures 1 and 2 show a system 1 for generating and controlling a non-thermal atmospheric pressure plasma (plasma) with a discharge space 10 and a flow controller 40, where the flow controller 40 has a first state (FIG. 1) and a second state (FIG. 2) occupies. FIG. 3 illustrates a further embodiment, which shows the state in which the flow regulator 40 is in the second state. FIGS. 4-6 show further embodiments in which the respective flow regulators assume the first state, so that no plasma jet emerges. The discharge space 10 has a first opening 12 and a second opening 14. In one embodiment according to the invention, the discharge space 10 is delimited by a dielectric 30 (FIGS. 1, 2, 3). The dielectric 30 can be designed in the form of a cylinder jacket.

The discharge space 10 extends along a longitudinal axis A. In the embodiment shown, the first opening 12 lies opposite the second opening 14.

The system 1 shown has a high-voltage electrode 20 which is arranged within the discharge space 10 (FIGS. 1-4). A ground electrode 22 is arranged outside the discharge space 10 on the dielectric 30, the ground electrode 22 being arranged near the second opening 14 (FIGS. 1-4). With the aid of the high-voltage electrode 20 and the ground electrode 22, when a voltage is applied, an electromagnetic field is generated in the discharge space 10 (FIGS. 1-4).

In one embodiment, the high-voltage electrode 20 and the ground electrode 22 are arranged outside the discharge space 10 on the dielectric 30 (FIG. 5).

The system 1 can have a microwave generator 202 and a microwave resonator 200 (FIG. 6).

The discharge space 10 can be connected to a working gas source 50 by means of a line element 52, in particular by means of a gas line element. The line element 52 can be fluidically connected on the one hand to the discharge space 10 and on the other hand to the working gas source 50 (FIGS. 1, 2, 5, 6). In particular, the line element 52 is arranged such that a working gas can be introduced from the working gas source 50 through the line element 52 through the first opening 12 into the discharge space 10. In one embodiment, the working gas source 50 is connected to the flow regulator 40 by means of a line element 52 and the flow regulator 40 is also connected to the discharge space 10 by means of a further line element 52 (FIGS. 3, 4).

The working gas volume flow 60 in the discharge space 10 can be controlled with the aid of the flow regulator 40. In the first state, the flow regulator 40 is arranged in such a way that no working gas passes through the first opening 12 into the discharge space 10 (FIGS. 1, 4, 5, 6). In the second state, working gas can pass from the working gas source 50 through the first opening 12 into the discharge space 10. Working gas flows from the first opening 12 through the discharge space 10 in the direction of the second opening 14 (FIGS. 2, 3). The flow regulator 40 can be a piezo valve (FIG. 4). A system 1 shown in FIG. 5 has a mixing arrangement 54, the flow regulator 40 having the mixing arrangement 54. The system 1 also has a further gas source 51. The further gas source 51 can be connected to the mixing arrangement 54. The mixing arrangement 54 is set up in particular to mix the working gas from the working gas source 50 with a further gas from the further gas source 51, so that a gas mixture is produced. The flow regulator is designed so that the resulting gas mixture is fed to the discharge space 10.

When an electromagnetic field is generated in the discharge space 10, a plasma 5 is generated in the discharge space 10 and pushed out of the discharge space 10 through the second opening 14 by the working gas volume flow 60 in the form of a plasma jet 6 (FIGS. 2, 3).

In one embodiment according to the invention, the flow regulator 40 is controlled with the aid of an automatic control unit 70 (FIGS. 1, 2, 5, 6). In particular, the state of the flow regulator 40 can be set with the aid of the automatic control unit 70, i. H. the automatic control unit 70 controls the flow regulator 40 such that it is in the first state or in the second state. It can thus be controlled by means of the automatic control unit 70 whether or not a plasma jet emerges from the discharge space.

FIGS. 7-15 show embodiments according to the invention of a system 1 for generating and controlling a non-thermal atmospheric pressure plasma with a large number of discharge spaces.

In FIGS. 7 a) -f) an embodiment of the system 1 in the form of a hand-held device 120 is shown in different perspectives. The illustrated handheld device 120 can be operated manually or by means of a robot. FIGS. 7d) -f) show the hand-held device 120 in a front view (d), a side view (e) and a perspective view (f). The hand-held device 120 shown has a housing 122. The hand-held device has a handle 140 and a head piece 130. The head piece 130 can have a multiplicity of cutouts 132.

FIGS. 7 a) -c) show an arrangement of four discharge spaces 10a, 10b, 10c, 10d in a frontal view (a), a cross section (b) and a perspective view (c).

The four second openings 14a, 14b, 14c, 14d are arranged in a common plane. They point in a common direction R. The individual recesses 132 and the second openings 14a, 14b, 14c, 14d can be arranged with respect to one another in such a way that a respective Plasma jet of the respective second opening 14a, 14b, 14c, 14d can exit through the respective recess 132.

FIGS. 8 to 12 show embodiments of a system 1 with a multiplicity of discharge spaces 10a, 10b, 10c. Each of the illustrated discharge spaces 10a, 10b, 10c has a respective first opening 12a, 12b, 12c and a respective second opening 14a, 14b, 14c. A high-voltage electrode 20a, 20b, 20c is arranged in each of the discharge spaces 10a, 10b, 10c.

The longitudinal axes Aa, Ab, Ac of the respective discharge spaces 10a, 10b, 10c can be arranged parallel to one another (illustrated in FIG. 8).

The second openings 14a, 14b, 14c of the respective illustrated exemplary systems 1 (FIGS. 8-12) are each arranged in a common plane E. The respective second openings 14a, 14b, 14c point in the same direction R. In particular, the surface normals Na, Nb, Nc point in the same direction R (FIGS. 8, 11). The longitudinal axes Aa, Ab, Ac can extend in the direction of the surface normals Na, Nb, Nc.

Figures 8 and 9 show a system 1 for generating and controlling a non-thermal atmospheric pressure plasma with three discharge spaces 10a, 10b, 10c. The discharge spaces 10a, 10b, 10c are connected to a common working gas source 50 via corresponding line elements 52a, 52b, 52c. The system 1 has flow regulators 40a, 40b, 40c, with the aid of which the introduction of a working gas from the working gas source 50 into a respective discharge space 10a, 10b, 10c is controlled.

The system 1 shown in FIGS. 8 and 9 has three discharge spaces 10a, 10b, 10c, the diameters Da, Db, De of the respective second openings 14a, 14b, 14c being identical (FIG. 8).

8 shows an arrangement of the system 1 in which all three flow regulators 40a, 40b, 40c are in their first state. This means that working gas from the working gas source 50 is not introduced into any of the three discharge spaces 10a, 10b, 10c through the respective first opening 12a, 12b, 12c.

An arrangement is illustrated in FIG. 9 in which a selected flow regulator 40b is in the second state. The other two flow regulators 40a, 40c are in their respective first states. In this configuration, working gas is introduced into the selected discharge space 10b, the gas supply of which is controlled with the aid of the selected flow regulator 40b. Plasma 5 arises in the selected discharge space 10b and emerges as a plasma jet 6 from the associated second opening 14b with the aid of the working gas volume flow 60. FIGS. 10-12 show a system 1 for generating and controlling a non-thermal atmospheric pressure plasma with two discharge spaces 10a, 10b, the respective associated second openings 14a, 14b of the illustrated discharge spaces 10a, 10b having different diameters Da, Db.

10 shows an arrangement of a system 1 in which a selected flow regulator 40b is in the second state, so that a plasma jet 6 emerges from the second opening 14b of the corresponding discharge space 10b. The flow regulators 40a, 40b can both be connected to an automatic control system 72. The automatic control system 72 can control both flow regulators 40a, 40b. In particular, the automatic control system 72 controls such that a flow regulator 40a, 40b is in the first state or in the second state.

FIG. 11 illustrates an arrangement in which the discharge spaces 10a, 10b are connected to different working gas sources 50a, 50b via the respective line elements 52a, 52b. I. E. the system has a plurality of working gas sources 50a, 50b. The flow regulators 40a, 40b can be controlled by a common automatic control system 72.

The system 1 illustrated in FIG. 12 has, in addition to a working gas source 50, which is connected to both discharge spaces 10a, 10b, a further gas source 51. Furthermore, the system 1 shown has a mixing arrangement 54b. The flow regulator 40b can have the mixing arrangement 54b.

The further gas source 51 can be connected to the mixing arrangement 54b. With the aid of the mixing arrangement 54b, the working gas from the working gas source 50 is mixed with a further gas from the further gas source 51. This gas mixture is fed to the discharge space 10b (by controlling the flow regulator 40b).

FIGS. 13, 14 and 15 show exemplary arrangements of the system 1 with a multiplicity of discharge spaces 10, the second openings 14 of the discharge spaces 10 facing a central region Z. The discharge spaces 10 are connected to a common working gas source 50. With the aid of a large number of flow regulators 40, the working gas flow in each of the discharge spaces 10 is controlled independently.

FIGS. 13 and 14 show a view from the front (FIG. 13) and a cross section (FIG. 14) of an exemplary arrangement in which the discharge spaces 10 are arranged on a cuboid volume. The second openings 14 are oriented towards the cuboid. In one embodiment, the discharge spaces 10 are arranged on four surfaces of the cuboid (FIG. 13). There are no discharge spaces 10 on two mutually opposite surfaces arranged (Fig. 14). An object 100 can be fed to the central region Z along a direction of movement B through these entrances 90, 92 that have arisen (FIG. 14).

15 shows an exemplary arrangement from the front, in which the discharge spaces 10 are arranged along a cylinder jacket. The second openings 14 point in the direction of the central region Z. The discharge spaces 10 can be arranged equidistant from one another in the circumferential direction U.

Claims

1. System (1) for generating and controlling a non-thermal atmospheric pressure plasma with:

- a discharge space (10) into which a working gas can be introduced via a first opening (12), a plasma (5) being able to be generated in the discharge space (10), the discharge space (10) having a second opening (14), so that the plasma (5, 6) can exit the discharge space (10) through this second opening (14), at least one high-voltage electrode (20) for generating an electromagnetic field for generating a plasma (5) in the discharge space (10), thereby characterized in that the plasma (5, 6) exiting through the second opening (14) is controlled by a flow regulator (40) of the system (1) which is designed to regulate a volume flow (60) of the working gas through the first opening (12 ) from a working gas source (50) into the discharge space (10), the flow regulator (40) also being designed to assume at least a first state and a second state, with no working gas from the working gas source (50) in the first state is fed to the discharge space (10), so that even when the electromagnetic field is generated in the discharge space (10), no plasma (5) emerges from the second opening (14), and in the second state the working gas from the working gas source (50) to the discharge space ( 10) is supplied, a plasma (5) is generated in the discharge space (10) and the plasma (5, 6) emerges from the second opening (14).

2. System (1) according to claim 1, characterized in that the system (1) has at least one ground electrode (22), the at least one high-voltage electrode (20) and the at least one ground electrode (22) for generating an electromagnetic field for generating a plasma (5) are formed in the discharge space (10).

3. System (1) according to one of claims 1 or 2, characterized in that the system (1) is set up to modulate the plasma (5) by a corresponding modulation of the volume flow (60) of the working gas, in particular exclusively by a corresponding modulation of the volume flow (60) of the working gas and in particular not to be generated by modulating the electromagnetic field, in particular where the system (1) is set up to generate only a continuous electromagnetic field in the discharge space (10).

4. System (1) according to one of claims 1 to 3, characterized in that the system (1) is designed to transfer the flow regulator (40) from the first state to the second state, so that when the electromagnetic field is generated in the discharge space ( 10) the plasma (5) is generated in the discharge space (10) and exits the discharge space (10) through the second opening (14), and / or to transfer the flow regulator (40) from the second state to the first state, so that when the electromagnetic field is generated in the discharge space (10), no plasma (5) emerges from the discharge space (10).

5. System (1) according to one of claims 1 to 4, characterized in that the flow regulator (40) has an active actuator or a passive actuator which is designed to assume at least the first or the second state, the passive actuator can be transferred from the first state to the second state in particular by the volume flow (60) of the working gas.

6. System (1) according to one of claims 1 to 5, characterized in that the system (1) has an automatic control unit (70) which is designed to control the flow regulator (40), so that by means of the automatic control unit (70 ) the flow regulator (40) is automatically adjustable in the first state and in the second state, wherein the automatic control unit (70) is further designed to transfer the flow regulator (40) for a selected period of time in the second state, so that a The period over which the working gas is introduced into the discharge space (10) can be set.

7. System (1) according to one of claims 1 to 6, characterized in that the system (1) has a mixing arrangement (54) which is designed to mix a further gas with the working gas, so that the resulting gas mixture in the discharge space (10) can be introduced, in particular wherein the flow regulator (40) has the mixing arrangement (54).

8. System (1) according to one of claims 1 to 7, wherein the system (1) has a plurality of discharge spaces (10, 10a, 10b, 10c), each discharge space (10, 10a, 10b, 10c) having a respective first Has opening (12, 12a, 12b, 12c) through which a working gas can be introduced into the respective discharge space (10, 10a, 10b, 10c), each discharge space (10, 10a, 10b, 10c) having an associated second opening (14 , 14a, 14b, 14c) through which the plasma can exit the respective discharge space (10, 10a, 10b, 10c), each discharge space (10, 10a, 10b, 10c) is assigned at least one high-voltage electrode (20, 20a, 20b, 20c) for generating an electromagnetic field for generating a plasma (5) in the respective discharge space (10, 10a, 10b, 10c), so that in each discharge space (10, 10a , 10b, 10c) a plasma (5) can be generated independently of the other discharge spaces (10, 10a, 10b, 10c), the plasma (5, 6) emerging through the associated second opening (14, 14a, 14b, 14c) is controlled by a flow controller (40, 40a, 40b, 40c) of the system (1) assigned to the respective discharge space (10, 10a, 10b, 10c), each flow controller (40, 40a, 40b, 40c) being designed to a volume flow (60) of the working gas through the respective first opening (12, 12a, 12b, 12c) of the respective discharge space (10, 10a, 10b, 10c) from a working gas source (50, 50a, 50b) into the respective discharge space (10, 10a, 10b, 10c), the respective flow regulator (40, 40a, 40b, 40c) still being designed for this t is to assume at least a first state and a second state, whereby in the first state no working gas is supplied from the working gas source (50, 50a, 50b) to the respective discharge space (10, 10a, 10b, 10c), so that in the respective discharge space ( 10, 10a, 10b, 10c) even when the electromagnetic field is generated in the respective discharge space (10, 10a, 10b, 10c), no plasma (5) emerges from the associated second opening (14, 14a, 14b, 14c), and in the second State the working gas from the working gas source (50, 50a, 50b) is fed to the respective discharge space (10, 10a, 10b, 10c) and a plasma (5) is generated there, and the plasma (5, 6) from the associated second opening (14, 14a, 14b, 14c) exits.

9. System (1) according to claim 8, characterized in that each discharge space (10, 10a, 10b, 10c) is assigned at least one ground electrode (22, 22a, 22b, 22c), the at least one high-voltage electrode (20, 20a, 20b, 20c) and the at least one ground electrode (22, 22a, 22b, 22c) are set up to generate an electromagnetic field for generating a plasma (5) in the respective discharge space (10, 10a, 10b, 10c).

10. System (1) according to one of claims 8 or 9, characterized in that the system (1) has an automatic control system (72) which is designed to control the plurality of flow controllers (40, 40a, 40b, 40c) of the System (1) to be controlled independently of one another, so that the flow regulators (40, 40a, 40b, 40c) can assume at least the first state or the second state independently of one another, so that plasma (5) only in a selected discharge space (10, 10a , 10b, 10c) and only exits from the second opening (14, 14a, 14b, 14c) of the selected discharge space (10, 10a, 10b, 10c).

11. System (1) according to claim 10, characterized in that the automatic control system (72) is designed to control the flow regulators (40, 40a, 40b, 40c) of the plurality of flow regulators (40, 40a, 40b, 40c) of the system (1) to be controlled independently of one another, so that one flow regulator (40, 40a, 40b, 40c) of the plurality of flow regulators (40, 40a, 40b, 40c) assumes the second state for a first period and all other flow regulators (40, 40a, 40b, 40c) of the plurality of flow regulators (40, 40a, 40b, 40c) assume the first state, and after the first period of time the flow regulators (40, 40a, 40b, 40c) of the plurality of flow regulators (40, 40a, 40b, 40c) ) assumes the first state, another flow controller (40, 40a, 40b, 40c) of the plurality of flow controllers (40, 40a, 40b, 40c) assuming the second state for a second period, the first and second periods of time following one another or overlap temporarily.

12. System (1) according to one of claims 8 to 11, characterized in that the

System (1) is designed so that each discharge space (10, 10a, 10b, 10c) of the plurality of discharge spaces (10, 10a, 10b, 10c) to a common

Working gas source (50) is connectable or connected, or wherein the system (1) is designed so that at least one discharge space (10, 10a, 10b, 10c) of the plurality of discharge spaces (10, 10a, 10b, 10c) to its own working gas source (50a, 50b) is connectable or connected.

13. System (1) according to one of claims 8 to 12, characterized in that the second openings (14, 14a, 14b, 14c) of the plurality of discharge spaces (10, 10a, 10b, 10c) in the same direction (R) or that the second openings (14, 14a, 14b, 14c) of the plurality of discharge spaces (10, 10a, 10b, 10c) are positioned or positionable in such a way that they face a central area (Z).

14. System (1) according to one of the preceding claims, characterized in that the at least one flow regulator (40, 40a, 40b, 40c) is continuously adjustable, so that the volume flow (60) through each discharge space (10, 10a, 10b, 10c) is continuously and individually adjustable.

15. System (1) according to one of the preceding claims, characterized in that the at least one flow regulator (40, 40a, 40b, 40c) is a proportional valve.

16. System (1) according to one of the preceding claims, characterized in that the system (1) is set up to control the volume flow (60) of the working gas in each discharge space (10, 10a, 10b, 10c) by means of the flow regulator (40, 40a, 40b, 40c) to modulate, the modulation of the volume flow (60) more than two Has modulation states, in particular wherein the modulation of the volume flow (60) is continuously adjustable.

17. System (1) according to one of the preceding claims, characterized in that each flow regulator (40, 40a, 40b, 40c) is set up to have a control time between 0.1ms and 1s, so that the volume flow (60) with a corresponding Time resolution can be modulated.

18. System (1) according to any one of the preceding claims, characterized in that the system (1) for each discharge space (10, 10a, 10b, 10c) has at least one associated sensor which detects a plasma parameter and which is set up to a to output a sensor signal indicative of the plasma parameter, the system being set up to regulate the at least one flow controller (40, 40a, 40b, 40c) on the basis of the sensor signal in such a way that a plasma parameter to be achieved for the respectively assigned discharge space (10, 10a, 10b, 10c) by modulating the volume flow.

19. System (1) according to one of the preceding claims, characterized in that the system (1) has exactly one high-voltage electrode and no more than two ground electrodes per discharge space (10, 10a, 10b, 10c).

20. System (1) according to one of the preceding claims, characterized in that the system (1) is set up to generate a capacitively coupled, an inductively coupled and / or a microwave-induced plasma in the working gas supplied through the first opening.

21. System according to one of the preceding claims, characterized in that each discharge space has exactly two openings - the first and the second opening.

22. A method for generating and controlling a non-thermal atmospheric pressure plasma using a system (1) according to one of claims 1 to 7, comprising the steps:

- Generation of an electromagnetic field in the discharge space (10),

- Setting the flow regulator (40) in a first state or a second state, wherein in the first state no working gas is supplied from the working gas source (50) to the discharge space (10), so that in the discharge space (10) even when the electromagnetic field is generated in the discharge space (10) no plasma (5) emerges from the discharge space (10), and in the second state the working gas from the working gas source (50) is supplied to the discharge space (10), in Discharge space (10) a plasma (5) is generated and the plasma (5, 6) emerges from the second opening (14).

23. The method according to claim 22, in particular for generating and controlling a non-thermal atmospheric pressure plasma using a system (1) according to one of claims 8 to 21, comprising the steps:

- Generation of an electromagnetic field in each discharge space (10, 10a, 10b, 10c) of the plurality of discharge spaces (10, 10a, 10b, 10c),

- Setting of each flow regulator (40, 40a, 40b, 40c) of the plurality of flow regulators (40, 40a, 40b, 40c) in a first state or a second state, wherein in the first state no working gas from the working gas source (50, 50a, 50b) is fed to the respective discharge space (10, 10a, 10b, 10c) of the multiplicity of discharge spaces (10, 10a, 10b, 10c), so that in the respective discharge space (10, 10a, 10b, 10c) the multiplicity of discharge spaces (10 , 10a, 10b, 10c) even when the electromagnetic field is generated in the respective discharge space (10, 10a, 10b, 10c) of the plurality of discharge spaces (10, 10a, 10b, 10c), no plasma from the respective discharge space (10, 10a, 10b, 10c) emerges, and in the second state the working gas from the working gas source (50, 50a, 50b) is supplied to the respective discharge space (10, 10a, 10b, 10c) of the plurality of discharge spaces (10, 10a, 10b, 10c), in respective discharge space (10, 10a, 10b, 10c) of the plurality of discharge spaces (10, 10a, 10b, 10c) a plasma (5) is generated and the plasma (5, 6) emerges from the associated second opening (14, 14a, 14b, 14c).