Device and method for generating dielectric barrier discharges, method for adjusting operating parameters of a control device, computer program and computer-readable storage medium

Abstract

The invention relates to a device for generating a dielectric barrier discharge, comprising a discharge reactor and a control device (13). The discharge reactor includes a thermoelectric component (1) and an electrode (2). The control device (13) includes a high-voltage source (12) configured to apply a high-voltage potential to the electrode (2) sufficient to ignite the dielectric barrier discharge, whereby the dielectric barrier discharge enriches a gas with reactive species. The control device (13) is configured to adjust the operating parameters of the high-voltage source (12) and the discharge reactor to achieve a desired composition of the enriched gas. A further aspect relates to a method for generating dielectric barrier discharges.Other aspects include a method for setting operating parameters of a control device, a computer program and a computer-readable storage medium.

Description

[0001] The subject matter of the present application is a device and a method for generating dielectric barrier discharges, a method for adjusting operating parameters of a control device, a computer program and a computer-readable storage medium.

[0002] From WO 2022 / 058 333 A1, a plasma reactor is known which is designed to cool a process gas by means of a Peltier element.

[0003] The object of the present invention is to provide an improved device for generating dielectric barrier discharges, as well as improved methods for operating the device and adjusting the operating parameters. Further objects include providing a computer program for implementing the method and a computer-readable storage medium for executing the computer program.

[0004] These problems are solved by the subject matter of the independent claims.

[0005] A device for generating a dielectric barrier discharge is proposed, comprising a discharge reactor and a control device. The discharge reactor comprises a thermoelectric component and an electrode. The control device comprises a high-voltage source and a low-voltage source. The high-voltage source is configured to apply a high-voltage potential to the electrode that is sufficient to ignite the dielectric barrier discharge, wherein the dielectric barrier discharge enriches a gas with reactive species. The low-voltage source is configured to adjust a current through the thermoelectric component. The control device is configured to suitably adjust operating parameters of the high-voltage source and the low-voltage source for a desired composition of the enriched gas.

[0006] The control device can thus be designed to always select the optimal operating point for the device. The control device can take into account the influence of the individual operating parameters on the generated reactive species and also the interactions between the individual operating parameters.

[0007] The operating point of the device is characterized by the setting of its operating parameters. These parameters determine which reactive species are generated in which quantities during the dielectric barrier discharge. Several operating parameters can now be specifically adjusted in the device to achieve a desired composition of the enriched gas with the reactive species.

[0008] The high-voltage source can be an alternating voltage source. Accordingly, the high-voltage potential applied to the electrode can vary with the frequency of the alternating voltage generated by the high-voltage source. High voltage here can be defined as an alternating voltage with an amplitude of 1 kV or more.

[0009] The low-voltage source can be a direct current source. Accordingly, a direct current can flow through the thermoelectric component. Depending on the direction of the direct current, the thermoelectric component can cool or heat / warm a gas in the discharge reactor.

[0010] The control device can determine the operating parameters through input signals applied to the low voltage source and the high voltage source.

[0011] In a first embodiment, a thermoelectric barrier discharge can be ignited in the discharge reactor, with the thermoelectric component acting as the counter electrode. The dielectric barrier discharge can be ignited between the electrode and the thermoelectric component acting as the counter electrode.

[0012] The thermoelectric component can be arranged in the reactor such that the temperature of the gas can be changed by the thermoelectric component. The thermoelectric component can either cool or heat the gas before and / or during the dielectric barrier discharge.

[0013] The thermoelectric component can in particular be a Peltier element or a component that comprises a thermoelectric ceramic material.

[0014] Since the device can be designed to select operating parameters to always achieve the desired gas composition for the activated gas, errors in the device's use, for example, for disinfection, can be eliminated. Additional system components for delivering chemical substances can therefore be dispensed with, saving consumables. If the reactive species are semi-stable chemicals with short half-lives that cannot be stored or supplied externally, the device offers a way to generate them in situ for direct application.

[0015] The device can be designed to adjust each operating parameter independently of the other operating parameters. The operating parameters can be adjusted dynamically, meaning they can be continually adjusted during ongoing operation. Various processes involving different active substances to be generated in situ can be simulated in a single device.

[0016] The operating parameters of the high-voltage source may comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential, and a pulse-width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse-width modulation.

[0017] The amplitude of the high-voltage potential of an alternating voltage signal generated by the high-voltage source can be used to adjust the number of reactive species generated during the dielectric barrier discharge and the ratio of the reactive species to each other. Overall, the number of reactive species generated increases with increasing amplitude. However, the proportion of each reactive species in the enriched gas composition differs depending on the selected high-voltage alternating voltage amplitude.

[0018] The amplitude of the high voltage can be up to 8 kV. The high-voltage alternating current can have a frequency between 15 kHz and 100 kHz, preferably 20 to 40 kHz.

[0019] The duty cycle can be adjusted via pulse-width modulation of the high-voltage potential. The duty cycle specifies the ratio of the time period during which a signal is applied to the electrode, resulting in dielectric barrier discharges, to the time period during which no signal is applied to the electrode, resulting in no dielectric barrier discharges. In this way, pulse-width modulation makes it possible to regulate the power of the dielectric barrier discharge. Pulse-width modulation of the high-voltage AC voltage thus changes the power density in the reactor, which directly influences which reactive species are generated during the dielectric barrier discharge. Furthermore, a modulation frequency can be set by the control device during pulse-width modulation.

[0020] The operating parameters of the low-voltage source, which are adjusted by the control device, can include the current flowing through the thermoelectric component. By changing the current, the intensity and direction of the heat transferred through the module can be adjusted, thus controlling the temperature of one side of the thermoelectric component.

[0021] The thermoelectric component can be used for both cooling and heating the gas in the discharge reactor. Cooling the gas, in particular, can increase the ozone concentration in the enriched gas. Heating the gas, however, increases the production of nitrogen oxides as reactive species, which degrade the ozone and thus lead to a reduced ozone concentration in the enriched gas.

[0022] The operating parameters mentioned here are not considered in isolation from one another. Rather, the control device can be designed to always consider the influence of each of the operating parameters mentioned on the composition of the enriched gas.

[0023] The control device can further be configured to control the chemical composition of the reactive species generated during the dielectric barrier discharge by performing pulse-width modulation of the high-voltage potential and / or adjusting the current intensity of the current flowing through the thermoelectric component and / or adjusting the amplitude of the high-voltage potential and / or adjusting the frequency of the high-voltage potential. Preferably, all four of the operating parameters mentioned here are always adapted to the desired chemical composition.

[0024] Furthermore, the control device can be designed to take into account environmental parameters that also have a significant influence on the composition of the reactive species generated during the dielectric barrier discharge.

[0025] In particular, the control device can be configured to consider at least one or more of the following environmental parameters when setting the operating parameters: a flow rate of the gas through the discharge reactor, a composition of the gas, and / or a temperature of the gas before entering the discharge reactor. Furthermore, an ambient temperature can be taken into account. Taking these environmental parameters into account can make it possible to model the plasma chemistry mapping function even more accurately and to adapt the composition of the enriched gas even more precisely to a desired composition.

[0026] Gases such as air, pure oxygen, synthetic air, or compressed dry air (CDA) can be introduced into the discharge reactor. These gases differ in their behavior during dielectric barrier discharge, so the type of gas used influences the type and quantity of reactive species generated. For example, the humidity of the gas used plays a role in the type and quantity of species generated during dielectric barrier discharge.

[0027] The device can include sensors that measure the environmental parameters. Alternatively, the influence of the environmental parameters can be indirectly accounted for by detecting and evaluating current pulses generated in the discharge reactor. Alternatively, the influence of the environmental parameters can be indirectly accounted for by comparing the composition of the generated species with the desired composition and adjusting the operating parameters based on the comparison result.

[0028] A surface of the electrode facing the thermoelectric component may have protrusions. A surface dielectric barrier discharge (SDBD) may occur at the protrusions, while volume dielectric barrier discharges (VDBD) may be triggered in the spaces between two protrusions where the electrode is spaced from the thermoelectric component. Accordingly, the device may enable a hybrid operating mode in which both surface and volume discharges are present.

[0029] The protrusions of the electrode can be in contact with the thermoelectric component. The protrusions can serve both as discharge points for surface discharges and as spacers, defining a distance between the thermoelectric component and the areas of the electrode that do not have protrusions. In this way, a volume for the volume discharges can be defined by the length of the protrusions.

[0030] The thermoelectric component can have a plurality of thermoelectric elements and metal bridges, each metal bridge connecting two adjacent thermoelectric elements. In particular, the metal bridges can connect the thermoelectric elements in a meandering pattern, with the metal bridges being arranged alternately on a top side of the thermoelectric component facing the electrode and on a bottom side of the thermoelectric component facing away from the electrode. The projections of the electrode can be arranged such that each projection lies exactly opposite a metal bridge on the top side of the thermoelectric component. The projection can be arranged centrally on the metal bridge. The metal bridges can be covered by a dielectric barrier layer, for example a ceramic layer. The projections can be adjacent to the dielectric barrier layer.

[0031] The electrode's protrusions allow heat generated on the electrode surface during the dielectric barrier discharge to be dissipated. The central arrangement of the protrusions relative to the metal bridges allows for particularly effective heat transfer and prevents unwanted parasitic discharges inside the thermoelectric component.

[0032] The high-voltage source can be autoresonant. A high-voltage source is referred to as autoresonant if it is designed to continuously adjust the frequency of the high-voltage signal it generates so that the discharge reactor it powers operates in a resonant mode. In an alternative embodiment, the discharge reactor can be operated at a frequency that does not correspond to the resonant frequency of the discharge reactor.

[0033] The control device can have a computing unit designed to determine the appropriate operating parameters for a desired composition of the enriched gas. The control device can then adjust the operating parameters according to the specifications of the computing unit.

[0034] The computing unit can be designed to determine the operating parameters in an analytical method, in a regression method, in a numerical method, in a computer-implemented method or by means of a self-learning algorithm.

[0035] The device may comprise sensors configured to determine the composition of the enriched gas, wherein the control device is configured to compare the composition determined by the sensors with the desired composition and to adjust the operating parameters depending on the result of the comparison. Accordingly, the sensors may enable feedback, in which a generated signal describing the gas composition in the enriched gas is compared with the desired gas composition. The feedback can be used to iteratively adjust the operating parameters, making it possible to achieve the desired gas composition.

[0036] During dielectric barrier discharge, current pulses can be generated in the discharge reactor. The device can be configured to measure the current pulses and determine the generated reactive species from the frequency and / or magnitude of the measured current pulses. The control device can be configured to regulate the operating parameters depending on the measured current pulses.

[0037] By using sensors or evaluating current pulses generated in the discharge reactor, it is possible to take into account the influence of environmental parameters on the composition of the enriched gas without having to measure every environmental parameter.

[0038] A further aspect relates to a method for generating a dielectric barrier discharge. In this method, the device described above can be used, in particular.

[0039] The method uses a device comprising a discharge reactor and a high-voltage source, wherein the discharge reactor comprises a thermoelectric component and an electrode, and wherein the control device comprises a high-voltage source and a low-voltage source. The high-voltage source is configured to generate a high-voltage potential between the electrodes. The method comprises the steps: - Setting a current through the thermoelectric component, wherein the current is set by the low-voltage source, - applying a high-voltage potential to the electrode so that a dielectric barrier discharge is ignited, wherein the dielectric barrier discharge enriches a gas with reactive species, wherein the high-voltage potential is applied by the high-voltage source, and - Adjusting operating parameters of the high voltage source and the low voltage source to produce a desired composition of the enriched gas, wherein the control device adjusts the operating parameters.

[0040] The operating parameters of the high-voltage source may comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential, and a pulse-width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse-width modulation, and wherein the operating parameters of the low-voltage source comprise a current intensity of the current flowing through the thermoelectric component.

[0041] The setting of the operating parameters performed by the control device to produce the desired composition of the enriched gas can be determined using a modeling function that determines from input variables describing a gas entering the discharge reactor and from the operating parameters output variables describing the gas leaving the discharge reactor.

[0042] The input variables may include at least one selected from the chemical composition of the gas entering the discharge reactor, the temperature of the gas entering the discharge reactor, and the flow rate of the gas entering the discharge reactor.

[0043] The input variables may comprise at least one selected from an ambient temperature and current pulses generated in the discharge reactor.

[0044] The output variables may include at least one selected from a temperature of the gas exiting the discharge reactor, a flow rate of the gas exiting the discharge reactor, and a composition of the gas exiting the discharge reactor.

[0045] A further aspect relates to a method for adjusting operating parameters of a control device that controls a discharge reactor. This can be the above-described control device, which has a high-voltage source and a low-voltage source, and the above-described discharge reactor, which has an electrode and a thermoelectric component. The method for adjusting operating parameters of the control device can be part of the above-described method for generating a dielectric barrier discharge.

[0046] The method for setting operating parameters of the control device comprises the following steps: - Determination of operating parameters of the high-voltage source and the low-voltage source so that a dielectric barrier discharge is generated at the electrode, producing a desired composition of the enriched gas, - Control of the operating parameters to the values ​​determined in the previous step.

[0047] The operating parameters of the high-voltage source may comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential, and a pulse-width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse-width modulation, and wherein the operating parameters of the low-voltage source comprise a current intensity of the current flowing through the thermoelectric component.

[0048] The setting of the operating parameters performed by the control device to produce the desired composition of the enriched gas can be determined using a modeling function that determines from input variables describing a gas entering the discharge reactor and from the operating parameters output variables describing the gas leaving the discharge reactor.

[0049] The input variables may include at least one selected from the chemical composition of the gas entering the discharge reactor, the temperature of the gas entering the discharge reactor, and the flow rate of the gas entering the discharge reactor.

[0050] The input variables may comprise at least one selected from an ambient temperature and current pulses generated in the discharge reactor.

[0051] The output variables may include at least one selected from a temperature of the gas exiting the discharge reactor, a flow rate of the gas exiting the discharge reactor, and a composition of the gas exiting the discharge reactor.

[0052] A further aspect relates to a computer program that executes the method described above for determining the operating parameters. The computer program comprises a first step in which the desired composition of the enriched gas is entered, and a second step in which the method is executed. The desired gas composition can be entered by a user or by a higher-level system to which the device is connected. Alternatively, the first step can be performed by a permanently programmed input of a desired gas composition.

[0053] The determination of the operating parameters can be carried out using an analytical method, a regression method, a numerical method, a computer-implemented method or a self-learning algorithm.

[0054] A further aspect relates to a computer-readable storage medium comprising the computer program described above, wherein the computer program comprises.

[0055] Advantageous aspects are described below. To facilitate referencing, the aspects are numbered consecutively. Aspect features are relevant not only in combination with the specific aspect to which they refer, but also when considered individually. 1. A device for generating a dielectric barrier discharge, comprising: - a discharge reactor comprising a thermoelectric component and an electrode, and - a control device comprising a high-voltage source and a low-voltage source, wherein the high-voltage source is configured to apply a high-voltage potential to the electrode which is sufficient to ignite the dielectric barrier discharge, wherein a gas is enriched with reactive species by the dielectric barrier discharge, wherein the low-voltage source is configured to adjust a current through the thermoelectric component, wherein the control device is configured to suitably adjust operating parameters of the high-voltage source and the low-voltage source for a desired composition of the enriched gas. 2. Device according to aspect 1, wherein the operating parameters of the high-voltage source comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential and a pulse-width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse-width modulation. 3. Device according to one of the preceding aspects, wherein the operating parameters of the low voltage source comprise a current intensity of a current flowing through the thermoelectric component. 4. Device according to one of the preceding aspects, wherein the control device is configured to control a chemical composition of the reactive species generated during the dielectric barrier discharge by the control device performing a pulse width modulation of the high-voltage potential and / or adjusting a current intensity through the thermoelectric component and / or adjusting an amplitude of the high-voltage potential and / or adjusting a frequency of the high-voltage potential. 5. Device according to one of the preceding aspects, wherein the control device is designed to take into account a flow rate of the gas through the discharge reactor when setting the operating parameters. 6. Device according to one of the preceding aspects, wherein the control device is designed to take into account a composition and / or a temperature of the gas at the inlet into the discharge reactor and / or an ambient temperature when setting the operating parameters. 7. Device according to one of the preceding aspects, wherein the thermoelectric component is a Peltier element. 8. Device according to one of the preceding aspects, wherein a surface of the electrode has projections. 9. Device according to aspect 8, wherein the electrode is opposite the thermoelectric component, and wherein the projections abut the thermoelectric component. 10. Device according to aspect 9, wherein the thermoelectric component comprises a plurality of thermoelectric elements, wherein the thermoelectric component comprises metal bridges, wherein each metal bridge connects two adjacent thermoelectric elements to each other, wherein the projections are arranged such that each projection lies exactly opposite one metal bridge on the top side of the thermoelectric component, wherein the top side of the thermoelectric component faces the electrode. 11. Device according to one of the preceding aspects, wherein the high voltage source is autoresonant. 12. Device according to one of the preceding aspects, wherein the control device has a computing unit which is designed to determine the suitable operating parameters for a desired composition of the enriched gas. 13. Device according to the previous aspect, wherein the computing unit is designed to determine the operating parameters in an analytical method, in a regression method, in a numerical method, in a computer-implemented method or by means of a self-learning algorithm. 14. Device according to one of the preceding aspects, wherein the device comprises sensors designed to determine the composition of the enriched gas, wherein the control device is designed to compare the composition determined by the sensors with the desired composition and to adapt the operating parameters depending on the result of the comparison. 15. Device according to one of the preceding aspects, wherein the thermoelectric component is opposite the electrode and is designed to act as a counter electrode to the electrode during the dielectric barrier discharge, or wherein the electrode is designed and arranged to ignite the dielectric barrier discharge against a surface at a ground potential. 16. Device according to one of the preceding aspects, wherein current pulses are generated in the discharge reactor during the dielectric barrier discharge, wherein the device is designed to measure the current pulses and to determine the generated reactive species from the frequency and / or the height of the measured current pulses, wherein the control device is designed to regulate the operating parameters as a function of the measured current pulses. 17. A method for generating a dielectric barrier discharge with a device comprising a discharge reactor having a thermoelectric component and an electrode, and a control device having a high-voltage source and a low-voltage source, comprising the steps: - applying a current to the thermoelectric component, whereby the current is set by the low-voltage source, - applying a high-voltage potential to the electrode so that a dielectric barrier discharge is ignited, wherein the dielectric barrier discharge enriches a gas with reactive species, wherein the high-voltage potential is applied by the high-voltage source, and - Adjusting operating parameters of the high voltage source and the low voltage source to produce a desired composition of the enriched gas, wherein the control device adjusts the operating parameters. 18. Procedures according to aspect 17, wherein the operating parameters of the high-voltage source comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential and a pulse width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse width modulation, and wherein the operating parameters of the low-voltage source include a current intensity of the current flowing through the thermoelectric component. 19. Method according to aspect 17 or aspect 18, wherein the setting of the operating parameters, which is carried out by the control device for generating the desired composition of the enriched gas, is determined using a modeling function (f(U,V)) which is derived from input variables (U) describing a gas entering the discharge reactor and from the operating parameters (V) output variables (W r) which describe the gas escaping from the discharge reactor. 20. The method according to aspect 19, wherein the input variables (U) comprise at least one selected from the chemical composition of the gas entering the discharge reactor, the temperature of the gas entering the discharge reactor, and the flow rate of the gas entering the discharge reactor. 21. Method according to aspect 19 or aspect 20, wherein the input variables (U) comprise at least one selected from an ambient temperature and current pulses generated in the discharge reactor. 22. Method according to one of aspects 19 to 21, wherein the output variables (W r ) at least one selected from a temperature of the gas exiting the discharge reactor, a flow rate of the gas exiting the discharge reactor and a composition of the gas exiting the discharge reactor. 23. A method for setting operating parameters of a control device controlling a discharge reactor, the control device comprising a high-voltage source and a low-voltage source, wherein the discharge reactor comprises an electrode and a thermoelectric component, wherein the high-voltage source is designed to apply a high-voltage potential to the electrode which is sufficient to ignite the dielectric barrier discharge, wherein the dielectric barrier discharge enriches a gas with reactive species, wherein the low-voltage source is designed to set a current to the thermoelectric component, the method comprising the steps of: - Determination of operating parameters of the high-voltage source and the low-voltage source so that a dielectric barrier discharge is generated at the electrode, producing a desired composition of the enriched gas, - Control of the operating parameters to the values ​​determined in the previous step. 24. Procedures according to aspect 23, wherein the operating parameters of the high-voltage source comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential, and a pulse-width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse-width modulation, and wherein the operating parameters of the low-voltage source comprise a current intensity of the current flowing through the thermoelectric component. 25. Method according to aspect 23 or aspect 24, wherein the setting of the operating parameters, which is carried out by the control device for generating the desired composition of the enriched gas, is determined using a modeling function (f(U,V)) which is derived from input variables (U) describing a gas entering the discharge reactor and from the operating parameters (V) output variables (W r ) which describe the gas escaping from the discharge reactor. 26. Procedures according to aspect 25, wherein the input variables (U) comprise at least one selected from the chemical composition of the gas entering the discharge reactor, the temperature of the gas entering the discharge reactor and the flow rate of the gas entering the discharge reactor. 27. Method according to aspect 25 or aspect 26, wherein the input variables (U) comprise at least one selected from an ambient temperature and current pulses generated in the discharge reactor. 28. Method according to any one of aspects 25 to 27, where the output variables (W r ) at least one selected from a temperature of the gas exiting the discharge reactor, a flow rate of the gas exiting the discharge reactor and a composition of the gas exiting the discharge reactor. 29. A computer program that carries out a method according to any one of aspects 23 to 28, the computer program comprising: a first step in which the desired composition of the enriched gas is entered, and a second step in which the method according to any one of aspects 23 to 28 is carried out. 30. Computer program according to aspect 29, wherein the determination of the operating parameters is carried out by means of an analytical method, a regression method, a numerical method, a computer-implemented method or a self-learning algorithm. 31. A computer-readable storage medium comprising a computer program for carrying out the method of any one of aspects 23 to 28, the computer program comprising: a first step in which the desired composition of the enriched gas is entered, and a second step in which the method according to any one of aspects 23 to 28 is carried out. 32. Computer-readable storage medium according to aspect 31, wherein the determination of the operating parameters is carried out by means of an analytical method, a regression method, a numerical method, a computer-implemented method or a self-learning algorithm.

[0056] Preferred embodiments are described below with reference to the figures. Fig. 1 shows a discharge reactor. Fig. 2 shows the discharge reactor and a control device. Fig. Figure 3 shows schematic diagrams showing the influence of operating parameters on the generated reactive species. Fig. Figure 4 schematically shows a method for generating a dielectric barrier discharge. Fig. Figure 5 shows schematically which variables are influenced by the operating parameters adjustable by the control device. Fig. 6 shows a discharge reactor according to an alternative embodiment.

[0057] Fig. Figure 1 shows a discharge reactor of a device for generating a dielectric barrier discharge, which comprises a thermoelectric component 1 and an electrode 2. The thermoelectric component 1 is a Peltier element.

[0058] The thermoelectric component 1 is an electrothermal converter. It is designed to change the temperature of a gas that is introduced into the discharge reactor as process gas and exits the discharge reactor as enriched gas. If a direct voltage is applied to the thermoelectric component 1 and a direct current flows through the thermoelectric component 1, a temperature difference is generated based on the Peltier effect, the Seebeck effect, or the Thomson effect. The Peltier element 1 can be used both for cooling and—if the current direction is reversed—for heating the process gas.

[0059] The thermoelectric component 1 has thermoelectric elements 3 which are connected to each other by metal bridges 4 to form a meander-shaped structure.

[0060] If the thermoelectric component 1 is a Peltier element, semiconductor elements are used as thermoelectric elements. The semiconductor elements are connected in series via metal bridges 4, alternating between p-doped semiconductor elements and n-doped semiconductor elements. The semiconductor elements can be made of bismuth telluride or silicon germanium, for example.

[0061] If a direct current is passed through the thermoelectric component 1, a temperature difference is created at the metal bridges 4 due to the thermoelectric effect, for example the Peltier effect, and thus a warm and a cold side of the component.

[0062] The thermoelectric component 1 comprises a first ceramic plate 5a and a second ceramic plate 5b. The first ceramic plate 5a is arranged on a top side facing the electrode. The second ceramic plate 5b is arranged on a bottom side facing away from the electrode.

[0063] The ceramic plates 5a, 5b may comprise or consist of aluminum oxide. Alternatively or additionally, the ceramic plates 5a, 5b may comprise or consist of aluminum nitride.

[0064] The ceramic plates 5a, 5b cover the metal bridges 4. In the Fig. In the embodiment shown in Figure 1, the ceramic plates 5a, 5b are arranged directly on the metal bridges 4. The metal bridges 4 form a thermal contact surface through which heat or cold is transferred to the ceramic plates 5a, 5b. The ceramic plates 5a, 5b act as heat-conducting plates. The ceramic plates 5a, 5b extract heat from the process gas or release heat to the process gas.

[0065] The electrode 2 is arranged parallel to one of the first ceramic plates 5a. The electrode 2 is opposite the thermoelectric component 1 and is in the Fig. 1, the electrode 2 is spatially separated from the thermoelectric component 1. A gap 6 is located between the electrode 2 and the thermoelectric component 1. The gap 6 between the thermoelectric component 1 and the electrode 2 can have a width between 0.01 mm and 1.0 mm, preferably between 0.05 mm and 0.5 mm.

[0066] The device is designed to trigger a dielectric barrier discharge between the electrode 2 and the thermoelectric component 1. The dielectric barrier discharge involves the ignition of a non-thermal atmospheric pressure plasma. During the dielectric barrier discharge, the process gas is enriched with reactive species.

[0067] A high-amplitude alternating voltage potential is applied to the electrode 2 with respect to an electrical potential of the thermoelectric component 1. A high-voltage alternating voltage is thus created between the thermoelectric component 1 and the electrode 2. A dielectric barrier discharge DBD is ignited between the thermoelectric component 1 and the electrode 2, with the ceramic plate 5a facing the electrode 1 acting as a dielectric barrier.

[0068] Alternatively or additionally, a layer acting as a dielectric barrier can be applied to the side of the electrode 2 facing the thermoelectric component 1.

[0069] A direct current flows through the thermoelectric component 1. A direct voltage potential difference through the low-resistance thermoelectric elements 3 of the thermoelectric component 1 is negligible compared to the high voltage required for the dielectric barrier discharge. Conversely, the current density typically occurring during the dielectric barrier discharge is small compared to the direct current flowing through the thermoelectric elements 3. Accordingly, the cooling function of the thermoelectric component 1 and the discharge function of the device do not negatively influence each other.

[0070] In an alternative embodiment, the thermoelectric component is not arranged opposite the electrode. In the alternative embodiment, the device can be configured to ignite the dielectric barrier discharge between the electrode and a surface to which a ground potential is applied.

[0071] The thermoelectric element 1 is used in the device both as a cooling or heating element, which sets the temperature of the process gas, and as a counter electrode, which, together with the electrode 2, triggers the dielectric barrier discharge. By combining the thermoelectric element 1 with the dielectric barrier discharge, the dielectric barrier discharge can be operated at a precisely controlled temperature and humidity, and the concentration and composition of active species generated during the dielectric barrier discharge can be controlled and maintained at a stable level.

[0072] The thermoelectric element 1 makes it possible to regulate the temperature of the process gas located in the gap 6 between the electrode 2 and the thermoelectric element 1. If a thermoelectric element 1 is used for dielectric barrier discharge, it is possible to precisely adjust the temperature of the process gas during the discharge. The gas composition of the gases generated during the dielectric barrier discharge depends, among other things, strongly on the temperature of the process gas. In particular, the proportions of ozone (O3) and nitrous gases (NO, NO2, NO x ) are determined by temperature. As temperature increases, the production of nitrous gases is favored and the decomposition mechanisms of ozone in favor of nitrous gases are accelerated.

[0073] The device further comprises a heat sink 9, which is attached to the ceramic plate 5b of the thermoelectric element 1, which faces away from the electrode 2. The heat sink 9 contributes to cooling the process gas in addition to the thermoelectric element 1.

[0074] The discharge reactor has a gas inlet 7 and a gas outlet 8. The process gas is admitted to the discharge reactor via gas inlet 7. In the discharge reactor, the process gas is enriched with reactive species. The gas enriched in the discharge reactor is discharged from the discharge reactor via gas outlet 8.

[0075] Furthermore, the device may alternatively or additionally comprise a fan 10 which is designed to conduct heat away from the heat sink and thereby contributes to cooling.

[0076] Fig. 2 shows the Fig. 1 and a control device 13 connected to the discharge reactor. The control device 13 has a low-voltage source 11 and a high-voltage source 12. The low-voltage source 11 applies a direct voltage in the low-voltage range to the thermoelectric component 1. A direct current therefore flows through the thermoelectric component 1. The thermoelectric component 1 is at a low-voltage electrical potential. The high-voltage source 12 applies a high alternating voltage potential to the electrode 2. Accordingly, a high potential difference arises between the thermoelectric component 1 and the electrode 2, and a dielectric barrier discharge occurs in the gap 6 between the electrode 2 and the thermoelectric component 1. The dielectric barrier discharge is a volume discharge.

[0077] The control device 13 is designed to control operating parameters of the low-voltage source 11 and operating parameters of the high-voltage source 12. For this purpose, the control device 13 can have a computing unit 14, for example a microcontroller, which is designed to issue control commands to the high-voltage source 12 and the low-voltage source 11.

[0078] The control device 13 is designed to adjust the operating parameters to achieve a desired composition of the enriched gas. The control device 13 can take into account that the type and quantity of reactive species generated are influenced by both the temperature of the thermoelectric component 1 and the amplitude and pulse width modulation of the high-voltage alternating potential applied by the high-voltage source 12 to the electrode 2.

[0079] The control device 13 accordingly enables the active ingredients or active ingredient combinations generated in the gas to be specifically produced in the desired concentrations and ratios by adjusting the operating parameters accordingly. For the desired product gas composition, the control device 13 selects an optimally efficient operating point as the operating point of the device. The operating or operating point of the device is characterized by the respective settings of the operating parameters of the high-voltage source 12 and the low-voltage source 11.

[0080] Since the reactive species generated in the process gas also depend on ambient conditions, for example on the type of process gas, on the temperature of the process gas upon entry into the discharge reactor and on the flow rate of the process gas through the discharge reactor, these ambient conditions can be taken into account by the control device 13 when setting the operating parameters.

[0081] The control device is designed to generate the desired composition of the activated gas by a targeted combination of the operating parameters, taking into account their mutual dependencies and the ambient conditions.

[0082] Fig. Figure 3 shows schematically the influence of the operating parameters on the generation of reactive species, where the Fig. The device shown in Figure 2 uses air as the process gas.

[0083] In the curves plotted in the first row, the amplitude of the high-voltage potential applied to the electrode is varied, while the temperature of the thermoelectric component is kept constant and no pulse width modulation of the high-voltage signal is performed.

[0084] In the four figures shown, from left to right, the concentration of ozone, nitrogen oxides, peroxides and acids in the activated gas is plotted for different amplitudes of the high-voltage signal.

[0085] The first curve, which shows the ozone concentration, shows that with increasing amplitude, the ozone concentration initially increases until a maximum is reached. If the amplitude is further increased beyond this maximum, the ozone concentration in the excited gas decreases. The reason for the decrease in the ozone concentration in the enriched gas at high amplitudes is that ozone depletion mechanisms are stimulated when the high-voltage signal has sufficiently high energy. In particular, nitrogen oxides are generated during the dielectric barrier discharge, which causes ozone depletion.

[0086] The second curve shows the concentration of nitrogen oxides in the enriched gas for different amplitudes of the high-voltage signal. The curve shows that at comparatively small amplitudes, almost no nitrogen oxides are generated. Only when the amplitude is sufficiently large does the concentration of nitrogen oxides in the enriched gas steadily increase with increasing amplitude.

[0087] The third curve shows the concentration of peroxides in the enriched gas for different amplitudes of the high-voltage signal. This concentration exhibits a maximum for medium amplitudes.

[0088] The fourth curve shows the concentration of acids in the enriched gas for different amplitudes of the high voltage signal.

[0089] The second line assumes that pulse-width modulation is used for the high-voltage signal. Pulse-width modulation allows the power of the high-voltage signal to be controlled by setting a duty cycle of the times when a signal is applied and the times when no signal is applied. The horizontal axis of the curves shown in the second line represents the power, which is directly proportional to the duty cycle of the pulse-width modulation. The vertical axis represents the respective concentrations of the reactive species in arbitrary units. The temperature during the gas discharge and the amplitude of the high-voltage signal remain constant.

[0090] The curves in the second row show that the concentration of all reactive species increases with increasing power. However, it should be noted that the curves shown here are purely schematic and arbitrary units are used. In particular, the ratio of the proportions of the reactive species to each other changes with increasing power.

[0091] The third row shows four curves in which the temperature of the thermoelectric component is varied while the power and amplitude of the high-voltage signal remain constant. The first curve, from the left, shows the ozone concentration. It can be seen that the ozone concentration decreases with increasing temperature. To achieve a high ozone concentration, the thermoelectric component must therefore cool the process gas. The second curve shows that the concentration of nitrogen oxides increases with increasing temperature. The third curve shows that the concentration of peroxides decreases with increasing temperature. The fourth curve shows that the concentration of acids increases with increasing temperature.

[0092] The Fig. The curves shown in Figure 3 are purely schematic and do not take into account the interaction of the operating parameters with each other with regard to the generated reactive species. To select the optimal operating point, i.e., to optimally adjust the operating parameters, a precisely modeled mapping function of the plasma chemistry is required.

[0093] Fig. Figure 4 shows schematically a method for generating a dielectric barrier discharge with the Fig. 2 shown device.

[0094] A gas flowing into the discharge reactor is described by input variables that are summarized in an input vector U. These input variables include an ambient temperature T U the device, a temperature T in which the gas has upon entering the gas inlet 7 and which depends on the ambient temperature T Umay vary under certain circumstances, a flow rate of the gas, which is referred to here as the mass flow of all gaseous components, and the concentrations c i 1, c i 2...c i m the individual chemical components that make up the gas flowing into the discharge reactor.

[0095] A gas leaving the discharge reactor is described by output variables that are summarized in an output vector W. The output variables include a temperature T out of the gas exiting the discharge reactor, a flow rate of the gas exiting the discharge reactor and the concentrations c a 1, c a 2...c a nof the individual chemical components that make up the gas exiting the discharge reactor. The gas exiting the discharge reactor contains all the chemical components of the gas that entered the discharge reactor and may also contain additional chemical components generated during the dielectric barrier discharge. These may include, for example, ozone, nitrogen oxides, or peroxides. Therefore, the number n of chemical components in the exiting gas is greater than or equal to the number m of chemical components in the gas entering the discharge reactor.

[0096] The control unit is now designed to influence the dielectric barrier discharge and the reactive species generated thereby. For this purpose, the control unit can regulate the operating parameters of the high-voltage source 12 and the low-voltage source 11. The operating parameters are Fig. 4 as manipulated variables in the vector V. The manipulated variables include an amplitude U D of the high-voltage potential applied by the high-voltage source 12 to the electrode 2, a frequency f of the high-voltage potential applied by the high-voltage source 12 to the electrode 2, a pulse width modulation PWM of the high-voltage potential, in which the duty cycle and a modulation frequency f can be adjusted, and a current intensity I tec a current which is set by the low-voltage source 11 through the thermoelectric component 1 and via which the temperature of the thermoelectric component 1 is regulated.

[0097] In the discharge reactor, short current pulses are generated during the dielectric barrier discharge, the frequency of which can be between 10 MHz and 50 MHz or whose frequency can be higher than 50 MHz. The current pulses are generated by an electric current flowing between electrode 2 and the respective counter electrode, whereby Fig. In the embodiment shown in Figure 2, the thermoelectric component 1 forms the counter electrode. The magnitude of the current pulses is, to a first approximation, proportional to the discharge intensity and, to a large extent, also proportional to the concentration of the newly generated chemical species. If pure oxygen is used as the process gas, the magnitude of the current pulses is proportional to the amount of ozone generated. Conclusions about the generated reactive species can be drawn from the frequency of the current pulses.

[0098] The current pulses generated in the discharge reactor can be detected and evaluated by the control device 13. In this way, the control device 13 can measure the type and quantity of reactive species generated.

[0099] In Fig. 4, the current pulses are denoted by S. The current pulses are coupled out of the discharge reactor and are captured in the input vector U. The input vector U thus contains the input variables that describe the ambient conditions and the gas entering the discharge reactor, as well as information obtained from the current pulses.

[0100] In the control device, the output variables are then precalculated using a modeling function f(U,V), whereby the input vector U and the vector V, in which the manipulated variables are summarized, are taken into account as parameters in the modeling function f(U,V). The modeling function f(U,V) is a multidimensional function with a large number of variables. The modeling function f(U,V) can be a purely analytical function calculated using an analytical method. The modeling function f(U,V) can be calculated using a regression method. The modeling function f(U,V) can be calculated using a numerical method. The modeling function f(U,V) can be a computer-implemented method, whereby the modeling function f(U,V) is carried out, for example, by a self-learning algorithm. The modeling function f(U,V) can be a combination of the method types mentioned here.

[0101] In the modeling function f(U,V) the output variables are represented in the form of an output vector W r The calculated output vector W r includes a calculated temperature T r out of the gas exiting the discharge reactor, a calculated flow rate and calculated concentrations c r 1, c r 2...c r n of the chemical components of the gas at the outlet from the discharge reactor. The calculated output vector W r The summarized quantities represent approximate values ​​of the actual output quantities. The more accurately the plasma chemistry in the dielectric barrier discharge is represented by the modeling function f(U,V), the smaller the deviation between the calculated output quantities and the actual output quantities.

[0102] A desired chemical composition of the enriched gas is transmitted to the control device by a user or by a higher-level system connected to the device. The computing unit 14 then determines the optimal operating point of the discharge reactor for generating the desired chemical composition. To do so, the computing unit 14 determines, based on the modeling function f(U,V), the values ​​to which the operating parameters of the low-voltage source 11 and the high-voltage source 12 should be set. The computing unit 14 can determine the operating parameters using an analytical method, a regression method, a numerical method, a computer-implemented method, or a self-learning algorithm.

[0103] The computing unit 14 then transmits the operating parameters to the high-voltage source 12 and to the low-voltage source 11, which can be arranged in a common driver module.

[0104] The control unit 13 is further configured to generate the input vector U, the vector V describing the manipulated variables, and the calculated output vector W r to the higher-level system. These values ​​can then be displayed on a screen by the higher-level system.

[0105] Fig. Figure 5 shows how the operating parameters variable by the control device 13 influence the reactive species produced.

[0106] On the left side of the Fig. Figure 5 shows the operating parameters that can be changed by the control device 13, as well as other parameters that describe the gas flowing into the discharge reactor. On the right side, process parameters that describe the dielectric barrier discharge are plotted. Arrows indicate which operating parameters or gas-describing parameters influence which process parameters.

[0107] The operating parameters that can be changed by the control device 13 include the amplitude of the high-voltage potential applied to the electrode 2, a pulse width modulation of the high-voltage potential applied to the electrode 2, and a current intensity through the thermoelectric component 1. Furthermore, the type of gas used and the flow rate of the gas are plotted on the left-hand side.

[0108] The type of gas used essentially determines which molecules are available as reactants in the dielectric barrier discharge.

[0109] The amplitude of the high-voltage potential applied to electrode 2 influences the energy and power density of the dielectric barrier discharge. Furthermore, the amplitude of the high-voltage potential applied to electrode 2 also influences the process temperature. A higher amplitude results in higher energies and a higher power density in the dielectric barrier discharge compared to a lower amplitude. This also generates more heat, which increases the process temperature.

[0110] The duty cycle of the pulse width modulation influences the power density of the dielectric barrier discharge and the process temperature. If the duty cycle increases the proportion of time periods during which no high-voltage potential is applied to electrode 2, the power density decreases and less heat is generated.

[0111] The current through thermoelectric component 1 influences the process temperature. The thermoelectric component 1 can cool or heat the gas in the discharge reactor.

[0112] The flow rate of the gas through the discharge reactor influences the power density of the dielectric barrier discharge and the process temperature.

[0113] Both the ozone concentration and the ozone production rate increase with increasing amplitude of the high-voltage signal, whereby saturation occurs at a sufficiently large amplitude and the ozone concentration and the ozone production rate do not increase further with an increasing amplitude of the high-voltage signal.

[0114] If the gas flow rate is increased, the generated reactive species, such as ozone, are transported away from the discharge reactor more quickly. Accordingly, the concentration of reactive species in the exiting gas decreases with increasing flow rate. At the same time, new process gas is supplied to the discharge reactor more quickly, so that the production rate of reactive species increases with increasing flow rate. As the flow rate increases, a thermal separation layer between electrode 2 and the dielectric barrier of the discharge reactor becomes smaller, thus improving heat dissipation and reducing the temperature of the process gas. A reduced temperature leads to an increased production rate of certain reactive species, such as ozone.Furthermore, reducing the thickness of the thermal barrier layer with increasing flow rate results in better diffusion of reaction products of the dielectric barrier discharge, which also increases the production rate of the reactive species.

[0115] The ozone concentration in the escaping gas increases with increasing duty cycle, with the duty cycle being controlled by pulse-width modulation of the high-voltage signal. With increasing duty cycle, the ozone concentration initially increases approximately linearly until a plateau in the ozone concentration is reached. Both an increasing amplitude and an increasing duty cycle can trigger ozone depletion mechanisms that explain plateaus in the ozone concentration with increasing duty cycle. The higher the amplitude of the high-voltage signal, the lower the duty cycle at which the corresponding plateau is reached. During a transition from a pulse-width modulated signal to a continuous signal, charge accumulated at the dielectric barrier can lead to an increase in the voltage during the micro-discharges.Accordingly, there is a sharp increase in ozone concentration when the utilization rate is above 90% and the signal is almost continuous.

[0116] Cooling the thermoelectric component influences the ozone concentration, with the ozone concentration decreasing with increasing temperature. There is a nearly linear relationship between the temperature in the discharge reactor and the ozone concentration in the exiting process gas.

[0117] Overall, each of the operating parameters—temperature of the thermoelectric component, amplitude of the applied high voltage, and pulse-width modulation of the applied high voltage—influences the generation of reactive species in the discharge reactor. There are significant interactions between the influences of the operating parameters, and the ambient conditions, particularly temperature, composition, and flow rate of the incoming gas, must also be considered. Taking all these parameters into account results in a well-modeled representation of the plasma chemistry during the dielectric barrier discharge, which is taken into account by the control device 13 of the present device.

[0118] Fig.Figure 6 shows a further embodiment of the discharge reactor. The electrode 6 has projections 15. The projections 15 are arranged on an upper side of the electrode 2, which faces the thermoelectric component 1. The projections 15 are arranged such that each projection 15 is centrally located opposite a metal bridge 4, which is arranged on the upper side of the thermoelectric component and connects two adjacent thermoelectric elements 3 to each other. The projections 15 rest against the ceramic layer 15a of the thermoelectric component 1.

[0119] The projections 15 fulfill various functions in the component. Surface discharges occur in the region of the projections. Accordingly, dielectric barrier discharges in the form of volume discharges and surface discharges occur in the discharge reactor. The ignition voltage for surface discharges is lower than for volume discharges.

[0120] The projections 15 also act as spacers between the electrode 2 and the thermoelectric component 1, thus determining the volume of the volumetric discharges. Furthermore, the projections 15 can dissipate heat generated at the electrode 2 to the thermoelectric component 1 via direct contact, thus reducing the temperature in the discharge space. This effect is particularly enhanced by the fact that each projection is centrally located opposite a metal bridge 4, since the metal bridges 4 have particularly high thermal conductivity.

[0121] In addition, the projections 15 hinder gas flow through the discharge reactor and thus enable better mixing of the process gas, which leads to improved cooling and thus an increased ozone production rate in the discharge reactor. List of reference symbols 1 thermoelectric component 2 electrodes 3 thermoelectric element 4 metal bridge 5a first ceramic plate 5b second ceramic plate 6 gap 7 Gas inlet 8 Gas outlet 9 heat sinks 10 fans 11 Low voltage source 12 High voltage source 13 Control device 14 Computing unit 15 lead QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2022 / 058 333 A1

[0002]

Claims

[1] Device for generating a dielectric barrier discharge, comprising: - a discharge reactor comprising a thermoelectric component (1) and an electrode (2), and - a control device (13) comprising a high-voltage source (12) and a low-voltage source (11), wherein the high-voltage source (12) is designed to apply a high-voltage potential to the electrode (2) that is sufficient to ignite the dielectric barrier discharge, wherein a gas is enriched with reactive species by the dielectric barrier discharge, wherein the low-voltage source (11) is designed to adjust a current through the thermoelectric component (1), wherein the control device (13) is designed to suitably adjust operating parameters of the high-voltage source (12) and the low-voltage source (11) for a desired composition of the enriched gas, wherein the device is designed to generate current pulses in the discharge reactor during the dielectric barrier discharge, wherein the device is designed to measure the current pulses and to determine the generated reactive species from the frequency and / or the height of the measured current pulses, wherein the control device is designed to regulate the operating parameters as a function of the measured current pulses. [2] Device according to claim 1, wherein the operating parameters of the high-voltage source (12) comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential and a pulse-width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse-width modulation. [3] Device according to one of the preceding claims, wherein the operating parameters of the low-voltage source (11) comprise a current intensity of a current flowing through the thermoelectric component (1). [4] Device according to one of the preceding claims, wherein the control device (13) is designed to control a chemical composition of the reactive species generated during the dielectric barrier discharge by the control device (13) performing a pulse width modulation of the high-voltage potential and / or adjusting a current intensity through the thermoelectric component (1) and / or adjusting an amplitude of the high-voltage potential and / or adjusting a frequency of the high-voltage potential. [5] Device according to one of the preceding claims, wherein the control device (13) is designed to take into account a flow rate of the gas through the discharge reactor when setting the operating parameters. [6] Device according to one of the preceding claims, wherein the control device (13) is designed to take into account a composition and / or a temperature of the gas at the entry into the discharge reactor and / or an ambient temperature when setting the operating parameters. [7] Device according to one of the preceding claims, wherein the thermoelectric component (1) is a Peltier element. [8] Device according to one of the preceding claims, wherein a surface of the electrode (2) has projections (15). [9] Device according to claim 8, wherein the electrode (2) is opposite the thermoelectric component (1), and wherein the projections (15) bear against the thermoelectric component (1). [10] Device according to claim 9, wherein the thermoelectric component (1) comprises a plurality of thermoelectric elements (3), wherein the thermoelectric component (1) has metal bridges (4), wherein each metal bridge (4) connects two mutually adjacent thermoelectric elements (3) to one another, wherein the projections (15) are arranged such that each projection (15) lies exactly opposite one metal bridge (4) on the upper side of the thermoelectric component (1), wherein the upper side of the thermoelectric component (1) faces the electrode (2). [11] Device according to one of the preceding claims, wherein the high voltage source (12) is autoresonant. [12] Device according to one of the preceding claims, wherein the control device (13) comprises a computing unit (14) which is designed to determine the suitable operating parameters for a desired composition of the enriched gas. [13] Device according to the preceding claim, wherein the computing unit (14) is designed to determine the operating parameters in an analytical method, in a regression method, in a numerical method, in a computer-implemented method or by means of a self-learning algorithm. [14] Device according to one of the preceding claims, wherein the device comprises sensors designed to determine the composition of the enriched gas, wherein the control device (13) is designed to compare the composition determined by the sensors with the desired composition and to adapt the operating parameters depending on the result of the comparison. [15] Device according to one of the preceding claims, wherein the thermoelectric component (1) is opposite the electrode (2) and is designed to act as a counter electrode to the electrode (2) during the dielectric barrier discharge, or wherein the electrode (2) is designed and arranged to ignite the dielectric barrier discharge against a surface at a ground potential. [16] Method for generating a dielectric barrier discharge with a device comprising a discharge reactor having a thermoelectric component (1) and an electrode (2), and a control device (13) having a high voltage source (12) and a low voltage source (11), comprising the steps: - applying a current to the thermoelectric component, the current being adjusted by the low-voltage source (11), - applying a high-voltage potential to the electrode (2) so that a dielectric barrier discharge is ignited, wherein the dielectric barrier discharge enriches a gas with reactive species, wherein the high-voltage potential is applied by the high-voltage source (12), and - Adjusting operating parameters of the high-voltage source (12) and the low-voltage source (11) to produce a desired composition of the enriched gas, wherein the control device (12) adjusts the operating parameters, wherein current pulses are generated in the discharge reactor during the dielectric barrier discharge, wherein the device measures the current pulses and determines the generated reactive species from the frequency and / or the height of the measured current pulses, wherein the control device regulates the operating parameters as a function of the measured current pulses. [17] Method according to claim 16, wherein the operating parameters of the high-voltage source (12) comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential and a pulse width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse width modulation, and wherein the operating parameters of the low-voltage source (11) include a current intensity of the current flowing through the thermoelectric component (1). [18] Method according to claim 16 or claim 17, wherein the setting of the operating parameters carried out by the control device (13) for producing the desired composition of the enriched gas is determined using a modeling function (f(U,V)) which is derived from input variables (U) describing a gas entering the discharge reactor and from the operating parameters (V) output variables (W r) which describe the gas escaping from the discharge reactor. [19] The method according to claim 18, wherein the input variables (U) comprise at least one selected from the chemical composition of the gas entering the discharge reactor, the temperature of the gas entering the discharge reactor and the flow rate of the gas entering the discharge reactor. [20] Method according to claim 18 or claim 19, wherein the input variables (U) comprise at least one selected from an ambient temperature and current pulses generated in the discharge reactor. [21] Method according to one of claims 18 to 20, wherein the output variables (W r ) at least one selected from a temperature of the gas exiting the discharge reactor, a flow rate of the gas exiting the discharge reactor and a composition of the gas exiting the discharge reactor. [22] Method for setting operating parameters of a control device (13) controlling a discharge reactor, wherein the control device (13) comprises a high voltage source (12) and a low voltage source (11), wherein the discharge reactor comprises an electrode (2) and a thermoelectric component (1), wherein the high-voltage source (12) is designed to apply a high-voltage potential to the electrode (2) which is sufficient to ignite the dielectric barrier discharge, wherein a gas is enriched with reactive species by the dielectric barrier discharge, wherein the low-voltage source (11) is designed to set a current to the thermoelectric component (1), the method comprising the steps of: - determining operating parameters of the high-voltage source (12) and the low-voltage source (11) so that a dielectric barrier discharge is generated at the electrode (2), in which a desired composition of the enriched gas is generated, - Control of the operating parameters to the values ​​determined in the previous step, wherein current pulses are generated in the discharge reactor during the dielectric barrier discharge, wherein the device measures the current pulses and determines the reactive species generated from the frequency and / or the height of the measured current pulses, wherein the control device regulates the operating parameters as a function of the measured current pulses. [23] Method according to claim 22, wherein the operating parameters of the high-voltage source (12) comprise at least one selected from an amplitude of the high-voltage potential, a frequency of the high-voltage potential and a pulse width modulation of the high-voltage potential, wherein a duty cycle and / or a modulation frequency are set during the pulse width modulation, and wherein the operating parameters of the low-voltage source (11) include a current intensity of the current flowing through the thermoelectric component (1). [24] A method according to claim 22 or claim 23, wherein the setting of the operating parameters, which is carried out by the control device (13) for generating the desired composition of the enriched gas, is determined using a modeling function (f(U,V)) which is formed from input variables (U) describing a gas entering the discharge reactor and from the operating parameters (V) output variables (W r) which describe the gas escaping from the discharge reactor. [25] A method according to claim 24, wherein the input variables (U) comprise at least one selected from the chemical composition of the gas entering the discharge reactor, the temperature of the gas entering the discharge reactor and the flow rate of the gas entering the discharge reactor. [26] Method according to claim 24 or claim 25, wherein the input variables (U) comprise at least one selected from an ambient temperature and current pulses generated in the discharge reactor. [27] Method according to one of claims 24 to 26, wherein the output variables (W r ) at least one selected from a temperature of the gas exiting the discharge reactor, a flow rate of the gas exiting the discharge reactor and a composition of the gas exiting the discharge reactor. [28] A computer program carrying out a method according to any one of claims 22 to 27, the computer program comprising: a first step in which the desired composition of the enriched gas is entered, and a second step in which the method according to any one of claims 22 to 27 is carried out. [29] Computer program according to claim 28, wherein the determination of the operating parameters is carried out by means of an analytical method, a regression method, a numerical method, a computer-implemented method or a self-learning algorithm. [30] A computer-readable storage medium comprising a computer program for carrying out the method of any one of claims 22 to 27, the computer program comprising: a first step in which the desired composition of the enriched gas is entered, and a second step in which the method according to any one of claims 22 to 27 is carried out. [31] A computer-readable storage medium according to claim 30, wherein the determination of the operating parameters is carried out by means of an analytical method, a regression method, a numerical method, a computer-implemented method or a self-learning algorithm.

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