A feedforward arc suppression circuit, control method, and high-voltage power supply for a high-voltage power supply

Abstract

This invention relates to the field of power electronics and discloses a feedforward arc suppression circuit, control method, and high-voltage power supply. The feedforward arc suppression circuit includes: a resonant cavity current sampling comparator, an input voltage sampling comparator, a first optocoupler, a first resistor, a second resistor, a PI regulation circuit, a second optocoupler, a control chip, and a third resistor. This invention uses a feedforward constant voltage control method, combined with an arc-suppressing resistor connected in series at the main circuit output, to achieve rapid arc suppression. Simultaneously, by sampling the input voltage and using the resonant cavity's feedforward method, it achieves constant output voltage and overcurrent protection, ensuring the overall reliability of the circuit. It achieves complete magnetic integration of the series resonant inductor and parallel resonant capacitor in the LCC converter, effectively improving the converter's power density and reducing its weight.

Description

Technical Field

[0001] This invention belongs to the field of power electronics technology, and in particular relates to a feedforward arc suppression circuit and control method for a high-voltage power supply. Background Technology

[0002] Electro-aerodynamic propulsion is a new type of propulsion method. Unlike traditional mechanical motion that generates thrust, the thrust comes from the "ion wind" generated by high-voltage ionization of air. At the same time, aircraft using this new propulsion method are lightweight.

[0003] The "heart" of an electro-aerodynamic propulsion aircraft is a high-power-density high-voltage power supply, and the stability of this power supply determines the flight reliability of such aircraft. Currently, high-voltage converters mostly use current-limiting circuits or series inductors at the output to suppress arcing. While current-limiting circuits can effectively suppress arcing at the output, the inability to quickly eliminate arcing and its energy leaves the circuit in a surge state, causing significant impact. Using inductors for arc suppression is problematic because the large size and weight of inductors are detrimental to achieving high power density in high-voltage power supplies. Summary of the Invention

[0004] The present invention provides a solution to the problem of the lack of a feedforward arc suppression circuit and control method for high-voltage power supplies with the aim of optimizing the overall lightweighting of the converter.

[0005] This invention provides a feedforward arc suppression circuit for a high-voltage power supply, the feedforward arc suppression circuit comprising:

[0006] The resonant cavity current sampling comparator, input voltage sampling comparator, first optocoupler, first resistor, second resistor, PI adjustment circuit, second optocoupler, control chip, and third resistor;

[0007] The input voltage sampling comparator is connected to the primary cathode of the first optocoupler, and the primary anode of the first optocoupler is connected to a high level.

[0008] The secondary collector of the first optocoupler is connected to the upper end of the first resistor, and the emitter is connected to the midpoint A of the series connection between the first resistor and the second resistor.

[0009] The midpoint A is connected to the secondary input terminal of the PI adjustment circuit, the output terminal of the PI adjustment circuit is connected to the cathode of the primary of the second optocoupler, the anode of the primary of the second optocoupler is connected to a high level, and the secondary of the second optocoupler is connected to the control chip.

[0010] The output terminal of the control chip is connected to the main circuit input terminal of the high-voltage power supply.

[0011] The output terminal of the main circuit of the high-voltage power supply is connected to the third resistor.

[0012] Preferably, the high-level output of the resonant cavity current sampling comparator and the PI adjustment circuit is equal to the high-level voltage connected to the primary anode of the first optocoupler and the second optocoupler.

[0013] Preferably, the control chip adopts a frequency conversion control method with a fixed duty cycle.

[0014] Preferably, the third resistor is a power resistor.

[0015] Preferably, the minimum frequency f of the control chip min and maximum frequency f max They are respectively:

[0016]

[0017]

[0018] Among them, L r For resonant inductance, C s For resonant capacitor, C p For parallel capacitors, V o For output voltage, V in_max For the maximum input voltage, V in_q This is the rated input voltage.

[0019] Preferably, the resistance value R of the third resistor is... y and power P y for:

[0020]

[0021]

[0022] U o For output voltage, V in_q For the rated input voltage, I limit Where I is the large input current, η is the converter efficiency, and I is the input current. i This is the input current.

[0023] To achieve the objective of the invention, the present invention also proposes a feedforward arc suppression control method for a high-voltage power supply, applied to a feedforward arc suppression circuit of a high-voltage power supply as described in any of the above claims, wherein the control method includes:

[0024] When arcing occurs at the output of the main circuit, the output voltage of the resonant cavity current sampling comparator exceeds the soft-start threshold voltage of the control chip, and the control chip enters soft-start mode.

[0025] When the input voltage exceeds the rated value, the input voltage sampling comparator outputs a low level, the primary and secondary diodes of the first optocoupler conduct, and the collector and emitter of the secondary phototransistor conduct, forming a voltage divider across the voltage formed by the first resistor and the second resistor. This voltage is then adjusted by the PI regulation circuit, which outputs a low level at the output of the PI regulation circuit. The primary diode and secondary phototransistor of the second optocoupler then conduct, thereby achieving frequency regulation of the control chip.

[0026] Preferably, the resistance value R of the third resistor is... y and power P y for:

[0027]

[0028]

[0029] U o For output voltage, V in_q For the rated input voltage, I limit Where I is the large input current, η is the converter efficiency, and I is the input current. i This is the input current.

[0030] Preferably, the minimum frequency f of the control chip min and maximum frequency f max They are respectively:

[0031]

[0032]

[0033] Among them, L r For resonant inductance, C s For resonant capacitor, C p For parallel capacitors, V o For output voltage, V in_max For the maximum input voltage, V in_q This is the rated input voltage.

[0034] To achieve the purpose of the invention, the present invention also proposes a high-voltage power supply, including a feedforward arc suppression circuit as described in any of the preceding claims.

[0035] The beneficial effects achieved by this invention are as follows: This invention discloses a feedforward arc suppression circuit and control method for a high-voltage power supply. The suppression circuit includes: a resonant cavity current sampling comparator, an input voltage sampling comparator, a first optocoupler, a first resistor, a second resistor, a PI adjustment circuit, a second optocoupler, a control chip, and a third resistor. Using a feedforward constant voltage control method, combined with an arc-suppressing resistor connected in series at the main circuit output, rapid arc suppression is achieved. Simultaneously, by sampling the input voltage and using the feedforward method of the resonant cavity, constant output voltage and overcurrent protection are achieved, ensuring the overall reliability of the circuit. This invention achieves complete magnetic integration of the series resonant inductor and parallel resonant capacitor in the LCC converter, effectively improving the power density of the converter and reducing its weight. Attached Figure Description

[0036] Figure 1 This is a structural diagram of a voltage doubler rectifier provided in an embodiment of the present invention;

[0037] Figure 2 This is a graph showing the relationship between the frequency and voltage gain of the LCC converter controlled by the feedforward arc suppression circuit in an embodiment of the present invention.

[0038] Figure reference numerals: 1. Resonant cavity current sampling comparator; 2. Input voltage sampling comparator; 3. First optocoupler; 4. First resistor; 5. Second resistor; 6. PI adjustment circuit; 7. Second optocoupler; 8. Control chip; 9. Third resistor. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0041] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediary element. In the following embodiments, "connection" should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have the transmission of electrical signals or data between them.

[0042] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Furthermore, the terms used in this specification include any and all combinations of the associated listed items.

[0043] like Figure 1 As shown, this invention proposes a feedforward arc suppression circuit for a high-voltage power supply used in electro-pneumatic propulsion. The feedforward arc suppression circuit includes a resonant cavity current sampling comparator 1, an input voltage sampling comparator 2, a first optocoupler 3, a first resistor 4, a second resistor 5, a PI adjustment circuit 6, a second optocoupler 7, a control chip 8, and a third resistor 9. The resonant cavity current sampling comparator 1 is connected to both the upper end of the first resistor 4 and the control chip 8. The input voltage sampling comparator 2 is connected to the primary cathode of the first optocoupler 3, and the primary anode of the first optocoupler 3 is connected to a high level. The secondary collector of the first optocoupler 3 is connected to the upper end of the first resistor 4, and the emitter is connected to the midpoint A of the series connection between the first resistor 4 and the second resistor 5. Midpoint A is connected to the secondary input terminal of the PI adjustment circuit. The output terminal of the PI adjustment circuit 6 is connected to the cathode of the primary winding of the second optocoupler 7, and the primary anode of the second optocoupler 7 is connected to a high level. The secondary winding of the second optocoupler 7 is connected to the control chip 8. The third resistor 9 is connected in series with the output terminal of the main circuit. The third resistor 9 is a power resistor.

[0044] The purpose of this invention is to provide a feedforward arc suppression circuit for high-voltage power supplies used in electro-pneumatic propulsion, achieving rapid arc suppression to prevent the circuit from entering surge mode, while simultaneously meeting the high power density requirements of electro-pneumatic propulsion high-voltage power supplies. The method employed is a feedforward constant voltage control method combined with an arc suppression resistor connected in series at the main circuit output, enabling rapid arc suppression. This invention also utilizes a feedforward constant voltage control method, combined with an arc suppression resistor connected in series at the main circuit output, to achieve rapid arc suppression. Furthermore, by sampling the input voltage and using a feedforward method with the resonant cavity, it achieves constant output voltage and overcurrent protection, ensuring the overall reliability of the circuit. This invention achieves complete magnetic integration of the series resonant inductor and parallel resonant capacitor in the LCC converter, effectively improving the converter's power density and reducing its weight.

[0045] Specifically, the high-level output of the resonant cavity current sampling comparator and the PI regulation circuit is equal to the high-level voltage connected to the primary anodes of the first optocoupler and the second optocoupler; in a specific embodiment, the control chip adopts a fixed duty cycle frequency conversion control method; the third resistor 9 is a power resistor. The output signals of the resonant cavity current sampling comparator 1 and the input voltage sampling comparator 2 are both voltage signals.

[0046] This invention also proposes a feedforward arc suppression control method for high-voltage power supplies, the principle and design process of which are as follows:

[0047] Step S10, Arc suppression control process: When arcing occurs at the output of the main circuit, the output voltage of the resonant cavity current sampling comparator 1 exceeds the soft-start threshold voltage of the control chip 8, and the control chip 8 enters soft-start mode.

[0048] Step S20, constant voltage control process: When the input voltage exceeds the rated value, the input voltage sampling comparator 1 outputs a low level, the primary and secondary diodes of the first optocoupler 3 are turned on, and the collector and emitter of the secondary phototransistor are turned on, forming a voltage divider on the voltage formed by the first resistor 4 and the second resistor 5, which is adjusted by the PI adjustment circuit 6, and a low level is output at the output terminal of the PI adjustment circuit 6. The primary diode of the second optocoupler 7 is turned on, and the secondary phototransistor is turned on, realizing the frequency adjustment of the control chip 8.

[0049] During the arc suppression control process, since the control chip adopts the PFM control mode with fixed duty cycle frequency adjustment, after entering the soft start, the frequency gradually decreases from the maximum frequency to the minimum frequency to realize the slow start of the main circuit and avoid surge phenomenon. When arcing occurs, the third resistor 9 realizes arc suppression of the electrode load through voltage division. At the same time, the third resistor 9 absorbs the energy on the electrode load during arcing to prepare for the soft start operation.

[0050] The resistance value R of the third resistor y and power P y for:

[0051]

[0052]

[0053] U o For output voltage, V in_q For the rated input voltage, I limit Where I is the large input current, η is the converter efficiency, and I is the input current. i The input current is [value]. During constant voltage control, the minimum frequency f of the control chip [is [value]. min and maximum frequency f max They are respectively:

[0054]

[0055]

[0056] Among them, L r For resonant inductance, C s For resonant capacitor, Cp For parallel capacitors, V o For output voltage, V in_max For the maximum input voltage, V in_q This is the rated input voltage.

[0057] According to specific embodiments provided by the present invention, the following technical effects are disclosed: The feedforward arc suppression circuit provided by the present invention uses a feedforward constant voltage control method, combined with an arc-suppression resistor connected in series at the output of the main circuit, to achieve rapid arc suppression. Simultaneously, by sampling the input voltage and using the feedforward method of the resonant cavity, it achieves constant output voltage and overcurrent protection, ensuring the overall reliability of the circuit. Overall, for the lightweight design objective of the electro-pneumatic propulsion high-voltage power supply, it achieves full magnetic integration of the series resonant inductor and parallel resonant capacitor of the LCC converter, effectively improving the power density of the converter and reducing its weight.

[0058] To achieve the purpose of the invention, the present invention also proposes a high-voltage power supply, including a feedforward arc suppression circuit as described in any of the preceding claims.

[0059] like Figure 2 The figure shown is a graph showing the relationship between the frequency and voltage gain of the LCC converter controlled by the feedforward arc suppression circuit in an embodiment of the present invention.

[0060] This invention provides a feedforward arc suppression circuit for a high-voltage power supply for electro-pneumatic propulsion, which can achieve rapid arc suppression, prevent the circuit from entering surge mode, and simultaneously achieve constant voltage output of the LCC high-voltage converter, thus meeting the high power density requirements of the high-voltage power supply for electro-pneumatic propulsion.

[0061] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0062] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0063] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A feedforward arc suppression circuit for a high-voltage power supply, characterized in that, The feedforward arc suppression circuit includes: The resonant cavity current sampling comparator, input voltage sampling comparator, first optocoupler, first resistor, second resistor, PI adjustment circuit, second optocoupler, control chip, and third resistor; The resonant cavity current sampling comparator is connected to both the upper end of the first resistor and the control chip. The input voltage sampling comparator is connected to the primary cathode of the first optocoupler, and the primary anode of the first optocoupler is connected to a high level. The secondary collector of the first optocoupler is connected to the upper end of the first resistor, and the emitter is connected to the midpoint A of the series connection between the first resistor and the second resistor. The midpoint A is connected to the secondary input terminal of the PI adjustment circuit, the output terminal of the PI adjustment circuit is connected to the cathode of the primary of the second optocoupler, the anode of the primary of the second optocoupler is connected to a high level, and the secondary of the second optocoupler is connected to the control chip. The output terminal of the control chip is connected to the main circuit input terminal of the high-voltage power supply. The output terminal of the main circuit of the high-voltage power supply is connected to the third resistor. The resistance value of the third resistor and power for: ； ； in For output voltage, V in_q The rated input voltage, For large input current, For converter efficiency, I i This is the input current.

2. The feedforward arc suppression circuit for a high-voltage power supply according to claim 1, characterized in that, The high-level output of the resonant cavity current sampling comparator and the PI adjustment circuit is equal to the high-level voltage connected to the primary anodes of the first optocoupler and the second optocoupler.

3. The feedforward arc suppression circuit for a high-voltage power supply according to claim 1, characterized in that, The control chip uses a frequency conversion control method with a fixed duty cycle.

4. The feedforward arc suppression circuit for a high-voltage power supply according to claim 1, characterized in that, The third resistor is a power resistor.

5. A feedforward arc suppression circuit for a high-voltage power supply according to any one of claims 1 to 4, characterized in that, The minimum frequency of the control chip and maximum frequency They are respectively: ； ； in, For resonant inductors, For resonant capacitor, C p For parallel capacitors, V o For output voltage, V in_max For maximum input voltage, V in_q This is the rated input voltage.

6. A feedforward arc suppression control method for a high-voltage power supply, applied to the feedforward arc suppression circuit of a high-voltage power supply as described in any one of claims 1-5, characterized in that, The control method includes: When arcing occurs at the output of the main circuit, the output voltage of the resonant cavity current sampling comparator exceeds the soft-start threshold voltage of the control chip, and the control chip enters soft-start mode. When the input voltage exceeds the rated value, the input voltage sampling comparator outputs a low level, the primary and secondary diodes of the first optocoupler conduct, and the collector and emitter of the secondary phototransistor conduct, forming a voltage divider across the voltage formed by the first resistor and the second resistor. This voltage is then adjusted by the PI regulation circuit, which outputs a low level at the output of the PI regulation circuit. The primary diode and secondary phototransistor of the second optocoupler then conduct, thereby achieving frequency regulation of the control chip.

7. The feedforward arc suppression control method for a high-voltage power supply according to claim 6, characterized in that, The resistance value of the third resistor and power for: ； ； in For output voltage, V in_q The rated input voltage, For large input current, For converter efficiency, I i This is the input current.

8. The feedforward arc suppression control method for a high-voltage power supply according to claim 6, characterized in that, The minimum frequency of the control chip and maximum frequency They are respectively: ； ； in, For resonant inductors, For resonant capacitor, C p For parallel capacitors, V o For output voltage, V in_max For maximum input voltage, V in_q This is the rated input voltage.

9. A high-voltage power supply, characterized in that, Includes a feedforward arc suppression circuit for a high-voltage power supply as described in any one of claims 1-5.

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