Disclosure of Invention
The invention provides a plasma reactor interelectrode constant voltage and constant current control device and a control method aiming at the technical problems in the prior art.
According to a first aspect of the invention, there is provided an interelectrode constant voltage and constant current control device of a plasma reactor, comprising a singlechip, a power amplification module, a high-frequency transformer, an interelectrode sampling circuit and an operational amplification circuit;
the singlechip generates a high-frequency sine wave, and groups the high-frequency sine wave to form a high-frequency comb-shaped wave, and the high-frequency comb-shaped wave is amplified by the power amplifying module and then controls the high-frequency transformer;
the high-frequency transformer converts the amplified high-frequency comb wave into a high-frequency high-voltage power supply and acts on the inner electrode and the outer electrode of the insulating dielectric barrier low-temperature plasma reactor;
the interelectrode sampling circuit collects interelectrode voltage and interelectrode current of the inner electrode and the outer electrode of the plasma reactor, and inputs the interelectrode voltage and interelectrode current to the singlechip after passing through the operational amplifier circuit;
and the singlechip performs data analysis on the inter-electrode voltage and inter-electrode current, adjusts the interval Toff between the high-frequency comb-shaped wave groups according to the analysis result and controls the average current value so as to enable the inter-electrode of the plasma reactor to keep constant voltage and constant current.
According to a second aspect of the present invention, there is provided a plasma reactor inter-electrode constant voltage and constant current control method, comprising:
the single chip microcomputer generates high-frequency sine waves, the high-frequency sine waves are arranged into groups to form high-frequency comb-shaped waves, the high-frequency comb-shaped waves are amplified by the power amplifying module and converted into high-frequency high-voltage power supplies by the high-frequency transformer, and the high-frequency high-voltage power supplies act on the inner electrode and the outer electrode of the low-temperature plasma reactor blocked by the insulating medium;
the interelectrode sampling circuit collects interelectrode voltage and interelectrode current of the inner electrode and the outer electrode of the plasma reactor, and inputs the interelectrode voltage and interelectrode current to the singlechip after passing through the operational amplifier circuit;
and the singlechip performs data analysis on the inter-electrode voltage and the inter-electrode current, and adjusts the interval Toff between the high-frequency comb-shaped wave groups according to the analysis result to control the average current value so as to enable the inter-electrode of the plasma reactor to keep constant voltage and constant current.
According to the interelectrode constant voltage and constant current control device and the control method of the plasma reactor, interelectrode voltage and current feedback is introduced, the singlechip is used for adaptively adjusting the comb-shaped wave spacing, so that the interelectrode current and voltage are kept relatively constant, the change of the working state of the plasma reactor caused by the change of interelectrode current and voltage is avoided, and the plasma reactor is ensured to always work in the preset optimal state of wire discharge ionization of low-temperature plasma.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention. In addition, the technical features of each embodiment or the single embodiment provided by the invention can be combined with each other at will to form a feasible technical scheme, and the combination is not limited by the sequence of steps and/or the structural composition mode, but is necessarily based on the fact that a person of ordinary skill in the art can realize the combination, and when the technical scheme is contradictory or can not realize, the combination of the technical scheme is not considered to exist and is not within the protection scope of the invention claimed.
Aiming at the technical problem that the constant current and voltage between the low-temperature plasma reactor cannot be ensured by a high-frequency power supply of the normal-pressure low-temperature plasma, the invention provides a constant-voltage and constant-current control device between the plasma reactor, which ensures that the low-temperature plasma reactor works in a preset working state of generating low-temperature plasma with optimal components by wire discharge ionization, namely the low-temperature plasma reactor can efficiently generate the low-temperature plasma containing a large amount of electrons, ions, atoms, molecules, active free radicals, rays and the like, and meanwhile, the content of nitrogen oxides is close to zero, and the service life of an electrode of a generator can be prolonged.
Referring to fig. 1, the plasma reactor inter-electrode constant voltage and constant current control device comprises a singlechip 31, a power amplification module 32, a high-frequency transformer 33, an inter-electrode sampling circuit 34 and an operational amplification circuit 35.
The singlechip 31 generates high-frequency sine waves, groups the high-frequency sine waves to form high-frequency comb-shaped waves, and controls the high-frequency transformer after the high-frequency comb-shaped waves are amplified by the power amplifying module 32; the high-frequency transformer 33 converts the amplified high-frequency comb wave into a high-frequency high-voltage power supply and acts on the inner electrode and the outer electrode of the insulating dielectric barrier low-temperature plasma reactor; the interelectrode sampling circuit 34 collects interelectrode voltage and interelectrode current of the inner electrode and the outer electrode of the plasma reactor, and inputs the interelectrode voltage and interelectrode current to the singlechip 31 after passing through the operational amplifier circuit 35; the singlechip 31 performs data analysis on the inter-electrode voltage and inter-electrode current, and adjusts the interval Toff between the high-frequency comb-shaped wave groups according to the analysis result to control the average current value so as to enable the inter-electrode of the plasma reactor to keep constant voltage and constant current.
It can be understood that the invention uses the single chip microcomputer 31 as a core control module to generate high-frequency sine waves, and organizes the same-frequency high-frequency signals into groups to form special comb-shaped waves capable of controlling the average current value by adjusting the interval Toff between the wave groups, namely the high-frequency comb-shaped waves in fig. 2, the generated high-frequency comb-shaped waves are amplified by power and then control the primary power supply of the high-frequency transformer 33, the high-frequency high-voltage power supply is converted by the high-frequency transformer 33 to generate upper kilovolt high-frequency high-voltage power, and the upper kilovolt high-frequency power supply acts on the inner electrode and the outer electrode of the low-temperature plasma generating tube blocked by the insulating medium. The model of the singlechip 31 may be C8051F, or may be any other model of singlechip, which is not limited herein.
The interelectrode sampling circuit 34 at the discharge end of the electrode is used for obtaining sampling signals, and obtaining interelectrode voltage and interelectrode current in real time, and meanwhile, the interelectrode sampling circuit has a current limiting protection function, so that damage to the ion reactor caused by interelectrode short circuit or isolated light discharge heavy current can be prevented.
The sampling signal is transmitted to the singlechip 31 after operational amplification, so that the singlechip 31 is used as a core control module to adaptively adjust the interval Toff of the high-frequency comb-type wave group in real time based on the sampling signal, namely the inter-reactor voltage and the inter-electrode current, and realize the inter-reactor constant voltage and constant current control.
Referring to fig. 3, the power amplification module includes a relay J1, a first MOS tube Q1 and a second MOS tube Q2, where a pin 1 of the relay J1 is grounded, a pin 2 is connected to a DC12V power supply, and is respectively connected to a source of the first MOS tube Q1 and a drain of the second MOS tube Q2 through a resistor R4, the drain of the first MOS tube Q1 is connected to the high-frequency transformer 33, a gate of the first MOS tube Q1 is connected to the drain of the second MOS tube Q2, a source of the second MOS tube Q2 is grounded, a gate of the second MOS tube is respectively connected to an out port of the single chip microcomputer 31 and is grounded through a resistor R6, and an IN port of the single chip microcomputer 31 is connected to an output end of the operational amplifier circuit 35. The type of the relay J1 is XH2.54, and the types of the first MOS tube Q1 and the second MOS tube Q2 are S12305DS and S12306DS respectively.
The pin 1 of the high-frequency transformer 33 is connected with the drain electrode of the first MOS transistor Q1, the pin 4 is grounded, the pin 5 and the pin 8 are both connected with the interelectrode sampling circuit 34, and the pin 5 is also grounded.
The interelectrode sampling circuit 34 includes a sampling resistor RS1, a pin 3 and a pin 4 of an electrode generator terminal output end D1 of the low-temperature plasma are both connected with a first end of the sampling resistor RS1, a second end of the sampling resistor RS1 is connected with a pin 5 of the high-frequency transformer 33, and a pin 1 and a pin 2 of the D1 are both connected with a pin 8 of the high-frequency transformer 33. The interelectrode voltage and interelectrode current of the electrode of the warm plasma are collected by a sampling resistor RS 1.
The operational amplifier circuit 35 includes a comparator, where the positive input end of the comparator is grounded, the negative input end is connected to the first end of the sampling resistor RS1 through a resistor R11, the negative input end is also connected to the output end of the comparator through a resistor R14, and the output end of the comparator is also connected to the IN port of the singlechip through a resistor R9.
The interelectrode voltage and the interelectrode current are acquired through a sampling resistor RS1 connected in series with the electrode discharge end, are fed back to a core control module taking a singlechip 31 through amplification treatment, and are subjected to data analysis by the control module, so that a high-frequency comb-type wave control high-frequency transformer 33 is generated to generate a constant-voltage constant-current generator high-frequency driving power supply.
Referring to fig. 4, a method for controlling constant voltage and constant current between plasma reactors according to an embodiment of the present invention includes:
step 1, a singlechip generates a high-frequency sine wave, the high-frequency sine wave is arranged into groups to form a high-frequency comb wave, the high-frequency comb wave is amplified by a power amplifying module and converted into a high-frequency high-voltage power supply by a high-frequency transformer, and the high-frequency high-voltage power supply acts on an inner electrode and an outer electrode of a low-temperature plasma reactor blocked by an insulating medium;
step 2, an interelectrode sampling circuit collects interelectrode voltage and interelectrode current of an inner electrode and an outer electrode of the plasma reactor, and the interelectrode voltage and interelectrode current are input into a singlechip after passing through an operational amplifier circuit;
and step 3, the singlechip performs data analysis on the inter-electrode voltage and the inter-electrode current, and adjusts the interval Toff between the high-frequency comb wave groups according to the analysis result to control the average current value so as to enable the inter-electrode of the plasma reactor to keep constant voltage and constant current.
Step 3, the singlechip performs data analysis on inter-electrode voltage and inter-electrode current, adjusts the interval Toff between the high-frequency comb wave groups according to the analysis result to control the average current value so as to keep constant voltage and constant current between the electrodes of the plasma reactor, and comprises the following steps:
judging whether the interelectrode voltage and the interelectrode current are higher than respective set values, if the interelectrode current is higher than a set current value and the interelectrode voltage is lower than the set voltage value, increasing the interval Toff between the high-frequency comb wave groups, and reducing the interelectrode current on the basis of unchanged single-pulse voltage current; if the inter-electrode current is lower than the set current value and the inter-electrode voltage is higher than the set voltage value, the interval Toff between the high-frequency comb wave groups is reduced, and the inter-electrode current is increased on the basis of unchanged single-pulse voltage current.
It can be understood that the control method for the constant voltage and constant current between the plasma reactor poles mainly comprises the following steps: the working steps of controlling and adjusting the high-frequency power supply module by taking the singlechip as a core control module according to the analysis result of the interelectrode voltage and interelectrode current data specifically comprise: judging whether the interelectrode current and interelectrode voltage are higher than set values; if the interelectrode current is increased, the interelectrode voltage is reduced, the discharge tends to arc discharge, and the singlechip is taken as a core control module to increase the comb wave Toff interval, so that the interelectrode current is reduced under the condition that the single-pulse voltage current is unchanged, and the occurrence of solitary light discharge is prevented; if the inter-electrode current decreases, the voltage increases, which causes that the inter-electrode gas discharge cannot be broken down, and the comb-shaped wave Toff interval decreases, so that the inter-electrode current increases under the condition that the single pulse voltage current is unchanged, and the occurrence of the discharge stop is prevented.
Referring to fig. 5, another embodiment of the present invention provides a method for controlling an inter-electrode constant voltage and constant current of a plasma reactor, the method comprising:
step 1', a singlechip generates a high-frequency sine wave, the high-frequency sine wave is arranged into groups to form a high-frequency comb wave, the high-frequency comb wave is amplified by a power amplifying module and converted into a high-frequency high-voltage power supply by a high-frequency transformer, and the high-frequency high-voltage power supply acts on an inner electrode and an outer electrode of a low-temperature plasma reactor blocked by an insulating medium;
step 2', an interelectrode sampling circuit and a temperature collector collect interelectrode voltage, interelectrode current and interelectrode temperature of an inner electrode and an outer electrode of the plasma reactor, and the interelectrode voltage, the interelectrode current and the interelectrode temperature are input into a singlechip after passing through an operational amplifier circuit;
and 3', the singlechip performs data analysis on the inter-electrode voltage, the inter-electrode current and the inter-electrode temperature, and adjusts the interval Toff between the high-frequency comb-shaped wave groups according to the analysis result to control the average current value so as to enable the inter-electrode of the plasma reactor to keep constant voltage and constant current.
It can be understood that the method for controlling the constant voltage and constant current between the electrodes of the plasma reactor can also adjust the interval between the high-frequency comb wave groups Toff according to the voltage, the current and the temperature between the electrodes of the plasma reactor, collect the temperature between the inner electrode and the outer electrode of the plasma reactor through the interelectrode sampling circuit and transmit the temperature to the singlechip; and the singlechip performs data analysis on the inter-electrode voltage, the inter-electrode current and the inter-electrode temperature, and adjusts the interval Toff between the high-frequency comb-shaped wave groups according to the analysis result to control the average current value so as to enable the inter-electrode of the plasma reactor to keep constant voltage and constant current.
Referring to fig. 6, a specific control procedure is to determine whether the integrated variation equivalent of the inter-electrode voltage and the inter-electrode temperature exceeds a set range;
if the comprehensive variation equivalent of the interelectrode voltage and interelectrode temperature is in a set range, the electrode works in a preset working state of wire discharge ionization generating the low-temperature plasma with the optimal component under the action of the high-frequency power supply, and the high-frequency comb-shaped wave waveform is kept unchanged by taking the singlechip as a core control module.
If the comprehensive variation equivalent of the interelectrode voltage and the interelectrode temperature exceeds the set range, judging whether the interelectrode current exceeds the set range; if the interelectrode current is larger than the set upper limit value, the discharge tends to arc discharge, and the singlechip is taken as a core control module to increase the comb wave Toff interval, so that the interelectrode current is reduced under the condition that the single-pulse voltage current is unchanged, and the occurrence of solitary light discharge is prevented; if the inter-electrode current is smaller than the set lower limit value, the inter-electrode gas discharge can not be broken down, and the high-frequency comb wave Toff interval is reduced, so that the inter-electrode current is increased under the condition that the single-pulse voltage current is unchanged, and the discharge stop is prevented from occurring. If the interelectrode current is also in the set range, the singlechip is used as a core control module to keep the waveform of the high-frequency comb wave unchanged.
And calculating comprehensive change equivalent of the interelectrode voltage and the interelectrode temperature according to the interelectrode voltage change difference and the interelectrode temperature change difference:
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wherein K is 1 、K 2 As the weight of the material to be weighed,is the difference of the interelectrode voltage change>Is the difference of the inter-electrode temperature variation.
According to the interelectrode constant voltage and constant current control device and the control method for the plasma reactor, interelectrode current and voltage signals at two ends of an electrode are collected, the interval Toff between special comb-shaped wave groups is controlled in a closed loop mode, the interelectrode current and voltage are kept stable, and the low-temperature plasma reactor is ensured to work in a preset working state of wire discharge ionization to generate low-temperature plasma with optimal components. This approach will yield the following benefits:
(1) The low-temperature plasma discharge is stabilized, so that the yield of the disinfection factors taking low-temperature plasmas such as electrons, ions, atoms, molecules, active free radicals, rays and the like as main bodies is stable, and the concentration of the disinfection factors is not reduced due to the deviation of the discharge state;
(2) The voltage and the current between electrodes are kept near the optimal working point of low-temperature plasma discharge, so that the quantity of the generated disinfection factors is large, and harmful substances such as nitrogen oxides generated by other discharge modes such as solitary discharge and the like are prevented, so that the purity of the disinfection factors is high, and the content of the nitrogen oxides is close to zero; the human-machine coexistence, active dynamic indoor air disinfection and purification and object surface disinfection are realized, and the safe and green dynamic disinfection has high practical value;
(3) The low-temperature plasma reactor stably works in a low-temperature plasma wire discharge state for a long time, so that the spark energy is reduced, and the explosion-proof safety of products is improved;
(4) The low-temperature plasma reactor stably works in a low-temperature plasma wire discharge state for a long time, so that the service life of an electrode of the generator is prolonged, and the quality of the whole disinfection product is improved.
(5) And the inter-electrode current and the voltage are kept stable based on inter-electrode voltage and current sampling closed-loop control of a special comb-shaped wave group interval Toff, so that the power supply almost has no overload current, and is safe and reliable.
In the foregoing embodiments, the descriptions of the embodiments are focused on, and for those portions of one embodiment that are not described in detail, reference may be made to the related descriptions of other embodiments.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.