Bipolar quasi square wave pulse power supply with continuously adjustable duty ratio
By designing a bipolar quasi-square-wave pulse power supply with continuously adjustable duty cycles of DC power, inductor, boost transformer and switch tube, the increase in the number of submodules and limited operating frequency in the prior art is solved. The problem is that high-frequency and high-voltage excitation and discharge times are improved, meeting the high-performance needs of DBD load.
Patent Information
- Application Number
- CN202420394588.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-01
- Publication Date
- 2024-12-10
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
When the output voltage of existing bipolar quasi-square-wave pulse power supply for dielectric barrier discharge load increases, the number of submodules increases, resulting in increased economic costs, synchronous driving and electrical isolation problems, and limited operating frequency , it is difficult to fully utilize DBD load performance.
Design a bipolar quasi-square-wave pulse power supply with continuous adjustment of duty cycles of DC power, inductor, boost transformer, diode and three types of switching tubes. By adjusting the frequency and duty cycle of switching tubes, the pulse width is achieved. The continuous adjustable and increase the number of discharges of the DBD load in one working cycle.
High-frequency, high-voltage bipolar quasi-square-wave excitation with high rise rate is achieved, which improves the discharge times of DBD load to four times, meets the needs of high-performance discharges, and improves the reliability of the pulsed power supply.
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Figure CN222147428U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of special power supplies for power electronics, in particular to a pulse power supply design for a dielectric barrier discharge load, and specifically to a bipolar quasi-square wave pulse power supply with a continuously adjustable duty cycle. Background Art
[0002] Dielectric barrier discharge (DBD) is a form of gas discharge, which is often used to generate low-temperature plasma containing a large number of active particles under atmospheric pressure. Therefore, it is widely used in material modification, energy conversion, environmental governance, biomedicine, aerospace and other fields. At present, the bipolar quasi-square wave pulse power supply suitable for dielectric barrier discharge load mainly includes three different forms of power supplies: pulse power supply based on multi-level circuit structure, pulse power supply based on Marx circuit structure and pulse power supply based on high-frequency pulse transformer structure. With the increase of output voltage level, the number of sub-module levels required for pulse power supply based on multi-level circuit structure and pulse power supply based on Marx circuit structure increases, and the number of switching devices increases sharply, which not only increases the economic cost of these two types of pulse power supplies, but also brings about the problem of synchronous driving and electrical isolation of switching devices, which greatly reduces the reliability of pulse power supply. In addition, these two types of pulse power supplies need to charge a large number of capacitors in the power supply one by one in each working cycle, which leads to the upper limit of the working frequency of the pulse power supply being limited, and it is difficult to give full play to the performance of DBD load. How to design a bipolar quasi-square wave pulse power supply that can achieve continuous adjustable pulse width and increase the number of discharges of the DBD load within a working cycle has become an urgent problem to be solved in the DBD application field and has important practical significance. Summary of the invention
[0003] The technical problem to be solved by the utility model is to provide a bipolar quasi-square wave pulse power supply with continuously adjustable duty cycle.
[0004] The technical solutions of the utility model are as follows:
[0005] The utility model provides a bipolar quasi-square wave pulse power supply with continuously adjustable duty cycle, characterized in that it comprises: a direct current power supply, an inductor, a boost transformer with a center tap, a diode, a first switch tube (S1), a second switch tube (S2), and a third switch tube (S3); the positive electrode of the direct current power supply is connected to the first end of the inductor; the negative electrode of the direct current power supply is respectively connected to the first end of the first switch tube (S1), the first end of the second switch tube (S2), and the first end of the third switch tube (S3); the second end of the inductor is respectively connected to the second end of the third switch tube (S3) and the anode of the diode; the cathode of the diode is connected to the center tap of the primary coil of the boost transformer; the second end of the first switch tube (S1) is connected to the first end of the primary coil of the boost transformer; the second end of the second switch tube (S2) is connected to the second end of the primary coil of the boost transformer; the first end of the secondary coil of the boost transformer is connected to the high voltage electrode of the dielectric barrier discharge load; the second end of the secondary coil of the boost transformer is connected to the low voltage electrode of the dielectric barrier discharge load.
[0006] Optionally, the first switch tube (S1), the second switch tube (S2) and the third switch tube (S3) are of the same model.
[0007] Optionally, the operating frequencies of the first switch tube (S1) and the second switch tube (S2) are equal, and the duty cycles of the drive signals of the first switch tube (S1) and the second switch tube (S2) are equal, and the sum of the duty cycles of the first switch tube (S1), the second switch tube (S2) and the third switch tube (S3) is 1.
[0008] Optionally, the duty cycle D of the first switch tube (S1) is 1 and the duty cycle D of the second switch tube (S2) 2 The range is: 0.1≤D 1 =D 2 ≤0.4; the duty cycle D of the third switch tube (S3) 3 The range is: 0.2≤D 3 ≤0.8.
[0009] Optionally, the first switch tube (S1), the second switch tube (S2) and the third switch tube (S3) are all NMOS; wherein the first end of the first switch tube (S1), the first end of the second switch tube (S2) and the first end of the third switch tube (S3) are all sources of the NMOS, and the second end of the first switch tube (S1), the second end of the second switch tube (S2) and the second end of the third switch tube (S3) are all drains of the NMOS.
[0010] Optionally, the voltage peak of the dielectric barrier discharge load can be achieved by adjusting the input voltage of the direct current power supply.
[0011] Optionally, the pulse width of the pulse power supply can be achieved by adjusting the frequency and duty cycle of the switching tube.
[0012] Performance advantages:
[0013] The advantages of the utility model compared with the prior art are:
[0014] (1) The pulse power supply disclosed in the utility model can provide a high-frequency, high-voltage, bipolar quasi-square wave excitation pulse with a high rise rate to meet the high-performance discharge requirements of the DBD load.
[0015] (2) The pulse power supply disclosed in the utility model can realize continuous adjustment of the bipolar quasi-square wave excitation pulse width within a certain range by controlling the frequency and duty cycle of the driving signal.
[0016] (3) The pulse power supply disclosed in the utility model can increase the number of discharges of the DBD load within one working cycle to four times. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 A schematic diagram of the structure of a bipolar quasi-square wave pulse power supply with continuously adjustable duty cycle provided by the utility model;
[0018] Figure 2 The equivalent circuit diagram of the pulse power supply provided by the utility model;
[0019] Figure 3 The switch tube driving timing diagram of the pulse power supply provided by the utility model;
[0020] Figure 4 The equivalent circuit diagram of the working mode 1 in the half working cycle of the pulse power supply provided by the utility model is
[0021] Figure 5 The equivalent circuit diagram of the working mode 2 in the half working cycle of the pulse power supply provided by the utility model is
[0022] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and meticulously below in conjunction with the accompanying drawings and preferred embodiments of the specification, but the protection scope of the present invention is not limited to the following specific embodiments.
[0023] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present utility model. DETAILED DESCRIPTION
[0024] In order to facilitate the understanding of the present invention, the following will provide a more comprehensive and detailed description of the present invention in conjunction with the accompanying drawings and preferred embodiments of the specification, but the protection scope of the present invention is not limited to the following specific embodiments.
[0025] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present utility model.
[0026] Embodiment 1:
[0027] like Figure 1 As shown, the utility model provides a bipolar quasi-square wave pulse power supply with a continuously adjustable duty cycle, the pulse power supply mainly consists of a current source type current conversion circuit and a step-up transformer, and is characterized in that it includes: a DC power supply, an inductor, a step-up transformer with a center tap, a diode, a first switch tube (S1), a second switch tube (S2), and a third switch tube (S3); the positive electrode of the DC power supply is connected to the first end of the inductor; the negative electrode of the DC power supply is respectively connected to the first end of the first switch tube (S1), the first end of the second switch tube (S2), and the first end of the third switch tube (S3); The second end of the inductor is respectively connected to the second end of the third switch tube (S3) and the anode of the diode; the cathode of the diode is connected to the center tap of the primary coil of the step-up transformer; the second end of the first switch tube (S1) is connected to the first end of the primary coil of the step-up transformer; the second end of the second switch tube (S2) is connected to the second end of the primary coil of the step-up transformer; the first end of the secondary coil of the step-up transformer is connected to the high-voltage electrode of the dielectric barrier discharge load; and the second end of the secondary coil of the step-up transformer is connected to the low-voltage electrode of the dielectric barrier discharge load.
[0028] In this embodiment, the first switch tube (S1), the second switch tube (S2) and the third switch tube (S3) are of the same model.
[0029] In this embodiment, the operating frequencies of the first switch tube (S1) and the second switch tube (S2) are equal, and the duty cycles of the drive signals of the first switch tube (S1) and the second switch tube (S2) are equal, and the sum of the duty cycles of the first switch tube (S1), the second switch tube (S2) and the third switch tube (S3) is 1.
[0030] In this embodiment, the duty cycle D of the first switch tube (S1) is 1 and the duty cycle D of the second switch tube (S2) 2 The range is: 0.1≤D1 =D 2 ≤0.4; the duty cycle D of the third switch tube (S3) 3 The range is: 0.2≤D 3 ≤0.8.
[0031] The equivalent circuit diagram of the pulse excitation generating circuit of the utility model is as follows Figure 2 As shown. Among them, E is the DC power supply, L is the inductor, D is the diode, i S is the current flowing through the inductor, S 1 , S 2 and S 3 They are the first switch tube (S1), the second switch tube (S2) and the third switch tube (S3), N P and N S are the number of turns of the primary and secondary windings of the transformer, L s1 , L s2 They are the leakage inductance of the primary coil of the transformer, L m1 , L m2 is the magnetizing inductance of the primary coil of the transformer. d and R d is the equivalent capacitance and equivalent resistance of the DBD load, i DBD and u DBD are DBD load current and load voltage respectively.
[0032] In this embodiment, control Figure 2 The switch drive timing of the circuit shown is as follows Figure 3 As shown. Figure 3 It can be seen that the operating frequencies of the first switch tube (S1) and the second switch tube (S2) are equal and the duty cycles of the drive signal of the first switch tube (S1) and the drive signal of the second switch tube (S2) are equal, and the sum of the duty cycles of the first switch tube (S1), the second switch tube (S2) and the third switch tube (S3) is 1.
[0033] In a positive half switching cycle, the system's operating mode can be divided into the following two modes.
[0034] Mode 1(t 0 -t 1 ): This stage is the pulse output mode, such as Figure 4 As shown, in this mode, the first switch tube (S1) is turned on, the second switch tube (S2) and the third switch tube (S3) are turned off, and the current source i formed by the DC power supply E and the energy storage inductor L S The step-up transformer provides energy to the DBD load, and the current i flowing through the energy storage inductor L SThe DBD load voltage and current both start to rise rapidly from zero at the same time. When the DBD load voltage rises to the maximum value, the DBD load current also crosses zero again. Then the DBD load voltage and current show a decaying oscillation trend and gradually tend to a steady state. The DBD load voltage remains stable and the DBD load current is approximately zero.
[0035] The circuit constraint equation of mode 1 is (L s1 and R d Small values are ignored):
[0036]
[0037] Among them, i m1 is the current flowing through the magnetizing inductance L m1 The current, N is the transformer ratio.
[0038] Mode 2 (t 1 -t 2 ): This stage is the pulse cutoff mode, such as Figure 5 As shown, in this mode, the third switch tube (S3) is turned on for the first time, and the first switch tube (S1) and the second switch tube (S2) are turned off. The DC power supply E provides energy to the energy storage inductor L, and the current i flowing through the energy storage inductor L is S Due to the reverse cutoff effect of diode D, the energy storage inductance L and the excitation inductance L m1 Mutually isolated, the excitation inductance L m1 The energy stored in the diode cannot flow through the diode and can only flow to the DBD load through the transformer. m1 And the equivalent capacitance C d At the same time, the equivalent resistance R d Energy is released, the DBD load voltage gradually decreases, and the DBD load current gradually decays to zero after a reverse rising process.
[0039] The circuit constraint equation of mode 1 is (L s1 and R d Small values are ignored):
[0040]
[0041] Among them, i m1 is the current flowing through the magnetizing inductance L m1 The current, N is the transformer ratio.
[0042] When a system is determined, the equivalent parameters of the transformer and the equivalent parameters of the dielectric barrier discharge load are determined, and the characteristic parameter values of the excitation pulse output by the pulse power supply can be obtained by solving the circuit constraint equations of mode 1 and mode 2 above.
[0043] When the system operates in steady state, the working modes of the positive half-cycle and negative half-cycle of the system are consistent.
Claims
1. A bipolar quasi-square wave pulse power supply with continuously adjustable duty cycle. It is characterized in that include: A direct current power supply, an inductor, a step-up transformer with a center tap, a diode, a first switch tube (S1), a second switch tube (S2), and a third switch tube (S3); the positive electrode of the direct current power supply is connected to the first end of the inductor; the negative electrode of the direct current power supply is respectively connected to the first end of the first switch tube (S1), the first end of the second switch tube (S2), and the first end of the third switch tube (S3); the second end of the inductor is respectively connected to the second end of the third switch tube (S3) and the anode of the diode; the cathode of the diode is connected to the center tap of the primary coil of the step-up transformer; the second end of the first switch tube (S1) is connected to the first end of the primary coil of the step-up transformer; the second end of the second switch tube (S2) is connected to the second end of the primary coil of the step-up transformer; the first end of the secondary coil of the step-up transformer is connected to the high voltage electrode of the dielectric barrier discharge load; the second end of the secondary coil of the step-up transformer is connected to the low voltage electrode of the dielectric barrier discharge load.
2. The bipolar quasi-square wave pulse power supply with continuously adjustable duty cycle according to claim 1, It is characterized in that The first switch tube (S1), the second switch tube (S2) and the third switch tube (S3) are of the same model.
3. The bipolar quasi-square wave pulse power supply with continuously adjustable duty cycle according to claim 1 or 2, It is characterized in that The first switch tube (S1), the second switch tube (S2) and the third switch tube (S3) are all NMOS; wherein the first end of the first switch tube (S1), the first end of the second switch tube (S2) and the first end of the third switch tube (S3) are all sources of the NMOS, and the second end of the first switch tube (S1), the second end of the second switch tube (S2) and the second end of the third switch tube (S3) are all drains of the NMOS.