High-voltage arc suppression circuit and high-voltage power supply equipment

Abstract

This application relates to a high-voltage arc suppression circuit and a high-voltage power supply device. The high-voltage arc suppression circuit includes a suppression circuit and a time-delay protection circuit; the load device is connected to the high-voltage power supply through the time-delay protection circuit; wherein: the time-delay protection circuit includes a time-delay switching circuit and an impedance reduction circuit connected in series, the time-delay switching circuit turning on after a preset time following a preset threshold; the impedance reduction circuit has a lower impedance than the suppression circuit; the suppression circuit is connected to the time-delay protection circuit, or connected in parallel with the time-delay switching circuit; the suppression circuit includes an inductor for suppressing the initial current rise of the load device. Using this circuit can reduce the footprint and lower production costs.

Description

Technical Field

[0001] This application relates to the field of high voltage protection technology, and in particular to a high voltage arc suppression circuit and a high voltage power supply device. Background Technology

[0002] High-voltage power supplies are widely used in industrial applications to drive various load devices. Their operating voltage range is wide, making it crucial to handle arcing caused by insulation issues. Arcing refers to electric arc discharge. During arcing, the energy storage components inside the power supply, such as capacitors, rapidly release energy through short-circuit points, generating high-amplitude surge currents that can potentially damage the load and power supply equipment.

[0003] In traditional technologies, inductors and resistors are typically connected in series or in parallel to suppress the arcing current, enabling arcing pass-through or protection shutdown. However, this approach involves the inductor continuously participating in current suppression during arcing, resulting in a large volt-second product that the inductor bears, making it prone to magnetic saturation. Therefore, only large air-core inductors can be used, hindering the miniaturization of high-voltage power supplies.

[0004] This shows that traditional technologies still suffer from problems such as large size and high cost of arc suppression circuits. Summary of the Invention

[0005] Therefore, it is necessary to provide a high-voltage arc suppression circuit and high-voltage power supply device that can reduce the volume and production cost of the above-mentioned technical problems.

[0006] In a first aspect, this application provides a high-voltage arc suppression circuit, which includes a suppression circuit and a time-delay protection circuit; the load device is connected to a high-voltage power supply through the time-delay protection circuit; wherein:

[0007] The delay protection circuit includes a delay switch circuit and an impedance reduction circuit connected in series. The delay switch circuit is turned on after the input voltage meets a preset threshold for a preset duration. The impedance of the impedance reduction circuit is lower than that of the suppression circuit.

[0008] The suppression circuit is connected to the delay protection circuit or connected in parallel with the delay switch circuit; the suppression circuit includes an inductor for suppressing the initial current rise of the load device.

[0009] In one embodiment, the suppression circuit includes an air-core inductor and / or a cored inductor.

[0010] In one embodiment, the delay switch circuit includes at least one overvoltage delay breakdown element; the conduction time of the overvoltage delay breakdown element is less than the volt-second product saturation time of the inductance of the suppression circuit.

[0011] In one embodiment, the overvoltage delay breakdown element includes a gas discharge tube and / or a varistor.

[0012] In one embodiment, the impedance reduction circuit includes a resistor and / or an inductor.

[0013] In one embodiment, the impedance reduction circuit includes one or more of a pure resistor, a pure inductor, an inductive resistor, and a resistive inductor.

[0014] In one embodiment, the suppression circuit is connected in parallel with the delay protection circuit; the delay protection circuit includes at least two secondary delay protection circuits; each of the secondary delay protection circuits includes a secondary delay switching circuit and a secondary impedance reduction circuit; wherein: the first-stage secondary delay protection circuit is connected in parallel with the suppression circuit; the subsequent-stage secondary delay protection circuit is connected in parallel with the secondary impedance reduction circuit of the adjacent preceding-stage secondary delay protection circuit.

[0015] In one embodiment, the impedance of the subsequent impedance reduction circuit is less than the impedance of the preceding impedance reduction circuit.

[0016] In one embodiment, the suppression circuit and the delay protection circuit are connected in parallel; the delay protection circuit includes a first delay protection circuit and a second delay protection circuit; the first delay protection circuit includes a first delay switching circuit and a first impedance reduction circuit connected in series; the second delay protection circuit includes a second delay switching circuit and a second impedance reduction circuit connected in series.

[0017] The second delay protection circuit is connected in parallel with the first impedance reduction circuit, and the first delay protection circuit is connected in parallel with the suppression circuit.

[0018] Secondly, this application provides a high-voltage power supply device, which includes a power supply body, an overvoltage protection device, and a high-voltage arcing suppression circuit as described above. The power supply body supplies power to the load device through the high-voltage arcing suppression circuit. The overvoltage protection device is used to control the connection between the power supply body and the load device to be disconnected when the load voltage exceeds a preset threshold.

[0019] The aforementioned high-voltage arc suppression circuit and high-voltage power supply equipment, through a time-delay protection circuit including a time-delay switch circuit and an impedance reduction circuit connected in series, wherein the time-delay switch circuit conducts after a preset time when the input voltage meets a preset threshold; the impedance of the impedance reduction circuit is lower than that of the suppression circuit; the suppression circuit is connected to the time-delay protection circuit, or connected in parallel with the time-delay switch circuit; the suppression circuit includes an inductor used to suppress the initial current rise of the load equipment, the time-delay protection circuit controls the conduction timing, and the suppression circuit limits the initial current rise rate, and the time-delay switch circuit conducts after the voltage threshold is met, the impedance reduction circuit provides a low-resistance path, which can effectively suppress the surge current during the high-voltage arcing process, while reducing the inductor volume, thereby achieving the technical effect of reducing the occupied volume and reducing production costs. Attached Figure Description

[0020] Figure 1 This is a block diagram of a high-voltage arc suppression circuit in one embodiment;

[0021] Figure 2 This is a block diagram of the high-voltage arc suppression circuit in another embodiment;

[0022] Figure 3 This is a block diagram of an arc suppression circuit in a traditional technology.

[0023] Figure 4 This is a timing diagram of an arc suppression circuit in a traditional technology.

[0024] Figure 5 This is a block diagram of the high-voltage arc suppression circuit in another embodiment;

[0025] Figure 6 This is a timing diagram of the low-arc operation condition of the high-voltage arc suppression circuit in one embodiment;

[0026] Figure 7 This is a timing diagram of the high-voltage arc suppression circuit under high-arc operating conditions in one embodiment;

[0027] Figure 8 This is a block diagram of the high-voltage arc suppression circuit in another embodiment;

[0028] Figure 9 This is a block diagram of a high-voltage arc suppression circuit in another embodiment. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0030] In one embodiment, a high-voltage arc suppression circuit is provided, comprising a suppression circuit 1 and a time-delay protection circuit 2; the load device is connected to the high-voltage power supply through the time-delay protection circuit 2; wherein:

[0031] The delay protection circuit 2 includes a delay switch circuit 21 and an impedance reduction circuit 22 connected in series. The delay switch circuit 21 is turned on after the input voltage meets a preset threshold for a preset duration. The impedance of the impedance reduction circuit 22 is lower than that of the suppression circuit 1.

[0032] like Figure 1 As shown, the suppression circuit 1 and the delay switch circuit 21 are connected in parallel, or as... Figure 2 As shown, the suppression circuit 1 is connected to the time delay protection circuit 2; the suppression circuit 1 includes an inductor for suppressing the initial current rise of the load device.

[0033] The delay switch circuit 21 is connected to the impedance reduction circuit 22 and the high-voltage power supply. By turning on the circuit after the input voltage meets a preset threshold and remains so for a preset duration, the conduction time is delayed, allowing the circuit to maintain a high-resistance state before high-voltage arcing occurs. For example, after receiving a voltage signal from the high-voltage power supply, the delay switch circuit 21 can be an electronic switch using an RC delay circuit, or a digital delay switch using a timing chip or other methods to achieve delay control, thereby enabling its own turn-on or turn-off.

[0034] Impedance reduction circuit 22 is connected to the load device via delay switch circuit 21. In this embodiment, impedance reduction circuit 22 can be configured with a path whose impedance is lower than that of suppression circuit 1 through resistors and / or inductors. After delay switch circuit 21 is turned on, it can provide a low-impedance path for the load device, thereby enabling rapid current rise.

[0035] The load device is connected to the high-voltage power supply through suppression circuit 1. Suppression circuit 1 is connected to time delay protection circuit 2, or connected in parallel with time delay switch circuit 21. Suppression circuit 1 limits the rate of change of current through inductance, suppressing the current rise rate in the early stage of high-voltage arcing, thereby preventing surge current from damaging the equipment.

[0036] Taking the frequent arcing during the startup of high-voltage dust removal equipment as an example, the high-voltage arcing suppression circuit in this embodiment can be such that after the high-voltage power supply starts, the delay switch circuit 21 detects whether the input voltage meets a preset threshold, and conducts after a preset time after the threshold is reached. At this time, the impedance reduction circuit 22 provides a low-impedance path, allowing the load equipment to enter a stable working state. Before the delay switch circuit 21 is turned on, the inductor in the suppression circuit 1 has already limited the initial current, effectively suppressing the surge current at the beginning of arcing. After the surge current is suppressed, the load equipment can then be connected to the high-voltage power supply through the conduction of the delay switch circuit 21, thereby achieving arcing suppression. It can be understood that compared with the inductor bearing the high voltage output of the power supply in the traditional technology, resulting in a large volt-second product, the delay protection circuit 2 of this application can conduct after the input voltage meets the preset threshold for a preset time, thereby achieving arcing suppression in a short time. This avoids the size requirements of the inductor for long-term suppression, thus eliminating the need to use a large hollow inductor to achieve the arcing suppression function, achieving the purpose of reducing size and cost.

[0037] This embodiment provides a high-voltage arc suppression circuit, which includes a time-delay protection circuit 2 comprising a time-delay switch circuit 21 and an impedance reduction circuit 22 connected in series. The time-delay switch circuit 21 conducts after the input voltage meets a preset threshold for a preset duration. The impedance of the impedance reduction circuit 22 is lower than that of the suppression circuit 1. The suppression circuit 1 is connected to the time-delay protection circuit 2 or in parallel with the time-delay switch circuit 21. The suppression circuit 1 includes an inductor for suppressing the initial current rise of the load device. The time-delay protection circuit 2 controls the conduction timing, and the suppression circuit 1 limits the initial current rise rate. The time-delay switch circuit 21 conducts after the voltage threshold is met. The impedance reduction circuit 22 provides a low-resistance path, which can effectively suppress the surge current during the high-voltage arcing process, while reducing the inductor volume, thereby achieving the technical effects of reducing the occupied volume and reducing production costs.

[0038] Furthermore, based on the recoverability of insulation, arcing can be categorized into two conditions: minor arcing and major arcing. Minor arcing occurs when insulation failure is not severe and insulation can be restored quickly by suppressing the voltage and current across the arcing point. Major arcing occurs when insulation failure is more severe and insulation cannot be restored even after prolonged suppression of the voltage across the arcing point. The high-voltage arcing suppression circuit provided in this application, through the disconnection of the delay switch circuit 21 within a preset time, allows insulation restoration within the preset time for minor arcing conditions. This ensures continued operation of the high-voltage power supply and load equipment after conduction, avoiding the impact of momentary arcing on the use of the load equipment. For major arcing conditions, if insulation has not recovered after the preset time, the low-impedance circuit provided by the impedance reduction circuit 22 allows for a rapid current increase in a short time. This enables the overvoltage protection circuit of the high-voltage power supply or load equipment to quickly identify the abnormality and cut off power, thereby improving equipment safety while avoiding the impact of momentary arcing on the continuity of load equipment operation.

[0039] In one embodiment, the suppression circuit includes an air-core inductor and / or a cored inductor.

[0040] Air-core inductors are inductors whose coils are supported by air, plastic, ceramic, or other non-magnetic materials. Because they lack a magnetic structure, they do not experience magnetic saturation. Using air-core inductors prevents magnetic saturation during high-current surges caused by ignition, maintaining a stable inductance value. Furthermore, the high-frequency oscillations generated by ignition are effectively suppressed by the air-core inductor, thus effectively filtering out high-frequency noise.

[0041] A magnetically cored inductor is created by incorporating a high-permeability magnetic material as a core within the coil, thereby giving the inductor a higher inductance. Examples of magnetically cored inductors include ferrite, iron-steel sheets, and iron powder cores. Using a magnetically cored inductor allows for more effective suppression of the initial current surge during ignition, thanks to its high inductance.

[0042] The suppression circuit can use either air-core inductors or magnetic-core inductors, and can be composed of air-core and magnetic-core inductors connected in series or parallel. Taking the series connection of air-core and magnetic-core inductors as an example, the magnetic-core inductor handles most of the steady-state or low-to-medium frequency current suppression, providing high inductance and reducing the overall size. The air-core inductor, in turn, suppresses high-frequency oscillations and transient impacts caused by arcing, preventing the magnetic-core inductor from overheating or saturating due to high-frequency current. Therefore, while ensuring sufficient inductance, it maintains high-frequency suppression capability, thus improving suppression robustness.

[0043] This embodiment provides a high-voltage arc suppression circuit that uses air-core inductors, magnetic-core inductors, or a combination of air-core and magnetic-core inductors to construct the suppression circuit. This maintains a small size and low production cost while improving suppression efficiency, thus achieving the technical effect of improving the ability to suppress surge current.

[0044] In one embodiment, the time-delay switching circuit includes at least one overvoltage delay breakdown element; the conduction time of the overvoltage delay breakdown element is less than the volt-second product saturation time of the inductance of the suppression circuit.

[0045] The overvoltage delay breakdown element can receive a voltage signal from a high-voltage power supply, and trigger breakdown conduction after the voltage signal exceeds a preset threshold and is maintained for a sufficient time, thus obtaining a voltage signal indicating the breakdown conduction state. For example, the overvoltage delay breakdown element can be one or more of a gas discharge tube, a varistor, or a silicon controlled rectifier.

[0046] The volt-second product saturation time can be defined as the time it takes for an inductor to reach saturation based on the cumulative effect of voltage stress acting on it over time. It is understood that traditional inductors are prone to magnetic saturation under continuous high-voltage stress, thus requiring the use of large-volume air-core inductors. However, in this embodiment, the preset time required for the overvoltage delay breakdown element to conduct is less than the volt-second product saturation time. This allows for effective insulation recovery under minor arcing conditions while avoiding suppressing the circuit inductor to reach magnetic saturation, thereby improving system stability.

[0047] Understandably, traditional time-delay switches require complex electronic circuits for timing control, increasing size and power consumption. In this embodiment, an overvoltage delay breakdown element automatically turns on the circuit after the voltage exceeds a preset threshold and is maintained for a sufficient time. This maintains a high-resistance state before high-voltage arcing occurs to limit the initial current and ensures that the conduction time matches the volt-second product characteristics of the suppression circuit inductance. Furthermore, this reduces the complexity of the switching circuit and shrinks its footprint.

[0048] This embodiment provides a high-voltage arcing suppression circuit that, by selecting an overvoltage delay breakdown component that automatically delays conduction after the voltage exceeds a threshold and matches the time characteristics of the inductor to maintain linear operation under voltage stress, can further reduce the risk of magnetic saturation of the inductor while suppressing arcing. This achieves the technical effect of improving circuit safety while reducing circuit size and production costs.

[0049] In one embodiment, the overvoltage delay breakdown element includes a gas discharge tube and / or a varistor.

[0050] The gas discharge tube is a discharge element filled with a sealed inert gas. When the voltage across its terminals reaches a certain threshold, the gas is ionized and breaks down, thus forming a low-resistance conductive channel. For example, the gas discharge tube may include one or more of the following: a single-stage gas discharge tube, a multi-stage gas discharge tube, etc.

[0051] A varistor can be a non-linear voltage-sensitive resistor that exhibits high resistance under normal voltage conditions, but when the voltage exceeds the varistor voltage, the resistance drops sharply, forming a short-circuit path, thereby achieving voltage clamping. For example, a varistor can include one or more of metal oxide varistors, silicon carbide varistors, etc.

[0052] This embodiment provides a high-voltage arc suppression circuit that uses a gas discharge tube and / or a varistor to obtain an overvoltage delay breakdown element. The gas discharge tube conducts through gas ionization after the voltage reaches the breakdown voltage, and the varistor conducts through a decrease in resistance after the voltage exceeds the threshold. It ensures that the conduction time is shorter than the volt-second product saturation time of the inductor in the suppression circuit, so that the inductor can operate within a safe range. The arc suppression function can be achieved without the need for a large air-core inductor, thereby achieving the technical effect of reducing the occupied volume and reducing production costs.

[0053] In one embodiment, the impedance reduction circuit includes a resistor and / or an inductor.

[0054] The impedance reduction circuit can be configured using a single inductor, a single resistor, or a composite of inductors and resistors connected in series or parallel. In one specific embodiment, by constructing an impedance reduction circuit using resistors and inductors, a higher impedance characteristic can be presented for high-frequency signals, while maintaining a lower impedance at low frequencies or under DC conditions, thereby optimizing the overall circuit impedance.

[0055] This embodiment provides a high-voltage arc suppression circuit. By using an impedance reduction circuit, including a single or combined structure of resistors and inductors, it can limit the rate of change of current during the high-voltage startup phase, reduce the risk of arcing, and achieve the technical effect of improving system stability and operational safety.

[0056] In one embodiment, the impedance reduction circuit includes one or more of a pure resistor, a pure inductor, an inductive resistor, and a resistive inductor.

[0057] The impedance reduction circuit can employ a single-element configuration based on pure resistance or a series-parallel combination configuration with other components; a single-element configuration based on pure inductance or a series-parallel combination configuration with other components; a single-element configuration based on inductive resistance or a series-parallel combination configuration with other components; or a single-element configuration based on resistive inductance or a series-parallel combination configuration with other components. By rationally configuring the types and connection methods of circuit components, the overall impedance in the circuit can be reduced, thereby improving current transmission efficiency or reducing voltage fluctuations. Furthermore, the inductive resistor can be a resistive element with parasitic inductance, and the resistive inductor can be an inductive element with parasitic resistance.

[0058] This embodiment provides a high-voltage arcing suppression circuit. By using an impedance reduction circuit that includes one or more of pure resistors, pure inductors, inductive resistors, and resistive inductors, and adjusting the circuit impedance using different types of components and their combinations, the circuit can achieve the technical effect of suppressing arcing during high-voltage startup and improving system stability and safety.

[0059] In one embodiment, the suppression circuit and the delay protection circuit are connected in parallel; the delay protection circuit includes at least two secondary delay protection circuits; each of the secondary delay protection circuits includes a secondary delay switching circuit and a secondary impedance reduction circuit; wherein: the first-stage secondary delay protection circuit is connected in parallel with the suppression circuit; the subsequent secondary delay protection circuit is connected in parallel with the secondary impedance reduction circuit of the adjacent preceding secondary delay protection circuit, and the impedance of the subsequent impedance reduction circuit is less than the impedance of the preceding impedance reduction circuit.

[0060] The secondary delay protection circuit can be a protection circuit that combines an independent delay switch circuit with an impedance reduction circuit. After meeting the voltage threshold condition and following a set delay, it gradually reduces the circuit impedance, thereby achieving multi-stage delay protection and reducing the current surge to the load equipment in stages. It is understood that traditional single-delay protection is difficult to match complex load characteristics. In this embodiment, the secondary delay protection circuit can receive a voltage signal from a high-voltage power supply, or a voltage signal or conduction status signal from the preceding secondary delay protection circuit. Through the synergistic effect of the delay switch and the impedance reduction circuit, it obtains a progressively changing impedance status signal.

[0061] For example, the first-stage secondary delay protection circuit can be activated after a preset time, based on the input voltage reaching an initial threshold and under the control of the delay switch circuit, thus providing initial delay protection during the initial ignition stage, and working with the suppression circuit to limit the initial surge current. The subsequent secondary delay protection circuit can be activated sequentially based on voltage conditions after the preceding secondary delay protection circuit is activated, and provides a lower impedance path through its independent impedance reduction circuit, thereby gradually reducing the system impedance during ignition and achieving a smooth current transition.

[0062] Furthermore, the components used in the secondary delay switching circuit of each secondary delay protection circuit may be different, and the structure of the resistor and / or inductor of the secondary impedance reduction circuit may also be different. This embodiment does not limit these components.

[0063] Taking the example of high-voltage equipment encountering insulation breakdown during startup, the high-voltage arcing suppression circuit in this embodiment can be configured such that after the high-voltage power supply starts, the first-stage secondary delay protection circuit and the suppression circuit work in parallel. After detecting that the input voltage reaches the initial threshold and is maintained for a preset time, the first-stage secondary delay protection circuit is turned on, while the inductor in the suppression circuit limits the initial current rise rate. Subsequently, the subsequent secondary delay protection circuits are turned on sequentially according to the voltage state. The secondary impedance reduction circuit of each subsequent secondary delay protection circuit provides a lower impedance path than the previous stage, allowing the current to gradually and smoothly transition to the normal operating state. By using a multi-stage delay protection and suppression circuit working in tandem, the surge current during the arcing process can be effectively suppressed, while avoiding the use of large-volume inductor components and reducing the occupied volume.

[0064] This embodiment provides a high-voltage arc suppression circuit. By setting at least two secondary delay protection circuits and making the impedance of the subsequent impedance reduction circuit less than that of the preceding stage, combined with the suppression circuit connected in parallel with the first stage, the secondary delay protection circuits are turned on and the impedance is reduced stage by stage, and the suppression circuit limits the current rise rate in the initial stage, multi-stage current control can be achieved during the arcing process. This not only effectively suppresses surge current, but also avoids the use of large-volume hollow inductors, thereby achieving the technical effect of reducing the occupied volume and reducing production costs.

[0065] In one embodiment, the suppression circuit and the delay protection circuit are connected in parallel; the delay protection circuit includes a first delay protection circuit and a second delay protection circuit; the first delay protection circuit includes a first delay switching circuit and a first impedance reduction circuit connected in series; the second delay protection circuit includes a second delay switching circuit and a second impedance reduction circuit connected in series.

[0066] The second delay protection circuit is connected in parallel with the first impedance reduction circuit, and the first delay protection circuit is connected in parallel with the suppression circuit.

[0067] The first delay protection circuit can be connected to the suppression circuit, the second delay protection circuit, the high-voltage power supply, and the load device. The first delay protection circuit can be activated by a first delay switching circuit after the input voltage meets a preset threshold and remains activated for a preset time, and work together with the first impedance reduction circuit to provide a low-impedance power supply path, thereby delaying activation after high-voltage arcing occurs to avoid direct impact on the load, while providing a stable power supply path for the load device.

[0068] The second delay protection circuit can be connected to the first impedance reduction circuit, the high-voltage power supply, and the load device. In this embodiment, the second delay protection circuit can be connected in parallel with the first impedance reduction circuit. The second delay switching circuit turns on after the voltage threshold is met, and works with the second impedance reduction circuit to provide another low-impedance path, thereby further reducing the overall system impedance after the first delay protection circuit turns on, and realizing a phased power supply transition.

[0069] This embodiment provides a high-voltage arcing suppression circuit. The suppression circuit is used to limit the initial current. The first delay protection circuit provides an initial low-impedance path after the voltage condition is met. The second delay protection circuit further reduces the system impedance after the first stage is completed. This can realize the gradual control of the current during the high-voltage arcing process, effectively suppress the surge current, thereby achieving the technical effects of reducing the size and number of inductors, reducing production costs, and improving power supply stability and transition smoothness.

[0070] like Figure 3 As shown, traditional arc suppression technology typically employs a parallel connection of an inductor, a reverse diode, and a resistor. The reverse diode acts as an inductor freewheeling current during the arcing-end phase, preventing secondary overvoltage due to sudden load impedance changes and subsequent repeated breakdowns. The resistor helps equalize the voltage across the series diodes during the arcing-end phase, preventing diode breakdown due to voltage equalization.

[0071] like Figure 4 As shown, the ignition process in traditional technology can be divided into 5 stages:

[0072] In stage a, before ignition, due to the "DC-passing, AC-blocking" characteristic of the inductor, the diode and resistor are bypassed, the load voltage equals the power supply output voltage, and the load current is the normal operating current. The inductor voltage is close to 0V, and the inductor current equals the load current.

[0073] In stage b, during ignition, due to the load short circuit during ignition, the load voltage is close to 0V. The power supply voltage is applied to the ignition suppression circuit, and the voltage across the inductor and resistor equals the power supply output voltage. The inductor current increases approximately linearly, while the resistor current remains approximately constant. The load current equals the sum of the inductor current and the resistor current, therefore it will rise rapidly and then increase linearly.

[0074] Phase c, the load voltage recovery phase after ignition, occurs because the load voltage has not yet returned to the power supply voltage. The diodes remain reverse-biased, and the inductor and resistor charge the normal load, causing the load voltage to gradually increase while the voltage across the inductor and resistor gradually decreases. Due to the characteristic that inductor current cannot change abruptly, the inductor current remains essentially constant during this phase, while the resistor current gradually decreases, thus the load current also gradually decreases.

[0075] In stage d, the load voltage has been charged to the power supply voltage, and the voltages across the inductor / resistor are close to 0V. Therefore, the resistor current is approximately 0A, and the inductor current freewheels through the reverse diode, with its amplitude remaining approximately constant. The load current equals the sum of the inductor and resistor currents, thus the load current rapidly decreases to the normal operating current.

[0076] In stage e, the ignition process ends, and the system returns to its pre-ignition state. The inductor voltage is approximately 0V, and the inductor current equals the normal operating current of the load. The load voltage equals the normal output voltage of the power supply.

[0077] Therefore, it is evident that during ignition, both the inductor and resistor bear the power supply voltage simultaneously, and after ignition, both inductor and resistor charge the load simultaneously. The ignition suppression circuit does not differentiate between strong and weak ignition. Throughout the entire process, both inductor and resistor participate in current suppression during ignition and load charging after ignition recovery. For weak ignition, after ignition, the inductor or resistor also limits the load charging speed, reducing the weak ignition pass-through speed. For strong ignition, because the inductor or resistor limits the ignition current throughout the ignition process, the increase in ignition current is limited. Therefore, the ignition protection current threshold must be lowered, increasing the risk of false ignition protection. Furthermore, strong ignition lasts a long time, and the inductor participates in the ignition suppression process throughout, resulting in excessively high volt-second loads on the inductor, which easily saturates it. Therefore, only air-core inductors can be used, significantly increasing the device size.

[0078] To more clearly illustrate the technical solution of this application, in order to solve the above problems, this application also provides a detailed embodiment to solve the above problems.

[0079] like Figure 5As shown, this application provides a simple, low-cost high-voltage arc suppression circuit that can automatically handle faults in both large and small arcing conditions and take corresponding measures. It includes a suppression circuit (corresponding to the first circuit in the figure), an impedance reduction circuit (corresponding to the second circuit in the figure), and a time-delay switch circuit. The time-delay switch circuit includes devices with a certain response time for overvoltage breakdown, such as a gas discharge tube (GDT) and / or a varistor (MOV). The first circuit includes inductive devices such as an air-core inductor and / or a magnetically cored inductor. The second circuit includes a resistor and / or a low-inductance inductor. The time-delay switch circuit is connected in parallel with the first circuit and then in series with the second circuit. The first circuit can be composed of air-core inductors and / or magnetically cored inductors connected in series or / and parallel; the time-delay switch circuit can be composed of a gas discharge tube (GDT) and / or a varistor and / or devices with time-delay conduction characteristics connected in series or / and parallel. The second circuit can be composed of one or more of pure resistors, pure inductors, inductive resistors, and resistive inductors connected in series or / and parallel.

[0080] The high-voltage arc suppression circuit in this embodiment can utilize a time-delay switching circuit. After a certain delay, it bypasses the first circuit and uses the second circuit to either perform a small arcing rapid pass-through function or a large arcing rapid shutdown function. The specific process is as follows:

[0081] (a) Small ignition conditions, such as Figure 6 As shown, the process includes the following:

[0082] Section a is the normal operating section. The voltage of the first circuit is close to 0V, the current of the first circuit is equal to the load current, the load voltage is approximately equal to the power supply output voltage, and the load current is normal.

[0083] Section b is the ignition section. The voltage of the first circuit is close to the power supply output voltage, the load voltage is close to 0V, and the current of the first circuit is equal to the load current, which rises slowly.

[0084] Section c is the ignition-stopped section. The first circuit current continues to flow through the load, charging it and causing the load voltage to rise, while the first circuit voltage falls. The load current equals the first circuit current, but the rate of increase slows down compared to the previous stage, and the current continues to rise.

[0085] Segment d is the second circuit operating segment. When the delay switch circuit is turned on, the voltage of the first circuit is quickly bypassed and clamped to near 0V, while the current remains approximately constant. After the delay switch circuit is turned on, the second circuit rapidly charges the load, causing the load current to increase rapidly and the load voltage to rise quickly, achieving rapid small-arc pass-through.

[0086] Segment e is the freewheeling section of the time-delay switching circuit. The load voltage is approximately equal to the power supply voltage, the load current returns to normal, the current in the first circuit decreases slowly, and the current continues through the time-delay switching circuit. The voltage in the first circuit is clamped close to 0V.

[0087] (ii) High-intensity fire-fighting conditions, such as Figure 7 As shown, the process includes the following:

[0088] Section a is the normal operating section. The voltage of the first circuit is close to 0V, the current of the first circuit is equal to the load current, the load voltage is approximately equal to the power supply output voltage, and the load current is normal.

[0089] Section b is the ignition section. The voltage of the first circuit is close to the power supply output voltage, the load voltage is close to 0V, and the current of the first circuit is equal to the load current, which rises slowly.

[0090] Section c is the second circuit operating section. When the time-delay switch is activated, the voltage of the first circuit is rapidly bypassed and clamped to near 0V, while the current remains approximately constant. After the time-delay switch is activated, the second circuit rapidly discharges to the load, causing the load current to increase rapidly. The arc detection circuit quickly detects this, provides rapid protection, and stops the high-voltage power supply output. This achieves rapid shutdown in the event of a large arc.

[0091] Section d is the ignition stop section. The high-voltage power supply is protected and shuts off, and the residual voltage of the high-voltage power supply is released through the second circuit and the time-delay switch circuit. The voltage across the load is 0V, and ignition is forcibly stopped.

[0092] This embodiment provides a high-voltage arc suppression circuit that, by introducing a delay switch circuit, can handle large and small arc conditions differently, and supports small-size and low-cost circuit design.

[0093] In some of these embodiments, such as Figure 8 As shown, the second circuit can be connected in series with the time delay switch circuit. Under normal operation, the second circuit does not participate in the operation. When sparking occurs, the time delay switch circuit introduces the second circuit to participate in the rapid pass-through of small sparking or the rapid protection of large sparking by conducting.

[0094] In some of these embodiments, such as Figure 9 As shown, a second delay circuit and a third circuit are connected in parallel on the second circuit. Similarly, a third delay switch circuit and a fourth circuit can be connected in parallel on the third circuit. That is, multiple secondary delay protection circuits, including delay switch circuits and impedance reduction circuits, are set up to achieve step-by-step ignition protection to meet the ignition conditions of different loads.

[0095] This embodiment provides a high-voltage arc suppression circuit that uses inductors and / or resistors to suppress arc current. Utilizing the response time of gas discharge tubes (GDTs) and / or varistors (MOVs), suppression circuits with different impedances are added in batches to suppress the arc current. For minor arcing conditions, after arcing ends, the high-impedance suppression circuit is switched to a low-impedance suppression circuit to quickly restore the load voltage, thus meeting the requirement for rapid arcing pass-through in minor arcing. For major arcing conditions, after a delay, the circuit switches to a low-impedance suppression circuit to accelerate the current rise, thereby speeding up the arcing protection judgment and ultimately achieving rapid shutdown protection in cases of major arcing. Furthermore, since the arc suppression inductor does not participate in current suppression throughout the entire process, its volt-second product is not high, allowing the use of a cored inductor. This significantly increases the current suppression effect in the initial stage of arcing and greatly reduces the inductor size, facilitating the miniaturization of the high-voltage power supply. The high-voltage arc suppression circuit provided in this embodiment, compared with other active arc detection and protection circuits, only adds passive components such as GDT or MOV, thus achieving low cost while meeting the requirements of fast dynamic response.

[0096] In one embodiment, a high-voltage power supply device is provided, which includes a power supply body, an overvoltage protection device, and a high-voltage arcing suppression circuit as described in any of the above embodiments. The power supply body supplies power to the load device through the high-voltage arcing suppression circuit. The overvoltage protection device is used to control the connection between the power supply body and the load device to be disconnected when the load voltage exceeds a preset threshold.

[0097] For example, the power supply unit may convert the input low-voltage AC or DC power supply into a high-voltage power output and supply power to the load device through a high-voltage arc suppression circuit and an overvoltage protection device, thereby providing the load device with the required high-voltage power.

[0098] The overvoltage protection device can be connected to both the power supply and the load device. In this embodiment, the overvoltage protection device can detect the voltage feedback signal from the load device and disconnect the power supply from the load device when the load voltage exceeds a preset threshold, thereby preventing damage to the load device due to overvoltage and improving system safety. For example, the overvoltage protection device can be a comparator-based voltage detection circuit combined with a thyristor-based fast-disconnect circuit to achieve rapid response and disconnection protection against abnormal voltages.

[0099] A high-voltage arcing suppression circuit can be connected to both the power supply and the load equipment. Through the cooperation of a time-delay switch circuit and suppression circuits with different impedances, it suppresses the initial surge current in stages when high-voltage arcing occurs. Different protection strategies are adopted according to the severity of the arcing, thereby suppressing the surge current during high-voltage arcing and protecting the load and power supply equipment. For example, under minor arcing conditions, the insulation can be restored within a certain time through the coordinated operation of the suppression circuit and the time-delay switch circuit. Therefore, after the time-delay switch circuit is turned on, the normal operation of the load equipment can be restored. However, if the insulation is not restored after the preset time of the time-delay switch circuit, the connection between the power supply and the load equipment can be disconnected through an overvoltage protection device, thus achieving rapid pass-through for minor arcing and rapid shutdown for major arcing.

[0100] This embodiment provides a high-voltage power supply device that converts low-voltage power into high-voltage output through the power supply body, and suppresses the initial surge current in stages through a high-voltage arc suppression circuit. At the same time, an overvoltage protection device detects and disconnects abnormal high voltage in real time, thereby achieving rapid response and differentiated handling during high-voltage arcing. It also reduces the size of the inductor, thereby reducing space occupation and production costs.

[0101] 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.

[0102] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. 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 application should be determined by the appended claims.

Claims

1. A high-voltage arc suppression circuit, characterized in that, The high-voltage arc suppression circuit includes a suppression circuit and a time-delay protection circuit; the load device is connected to the high-voltage power supply through the time-delay protection circuit; wherein: The delay protection circuit includes a delay switch circuit and an impedance reduction circuit connected in series. The delay switch circuit is turned on after the input voltage meets a preset threshold for a preset duration. The impedance of the impedance reduction circuit is lower than that of the suppression circuit. The suppression circuit is connected in parallel with the delay protection circuit; the delay protection circuit includes at least two secondary delay protection circuits; each secondary delay protection circuit includes a secondary delay switching circuit and a secondary impedance reduction circuit; wherein: the first-stage secondary delay protection circuit is connected in parallel with the suppression circuit; the subsequent-stage secondary delay protection circuit is connected in parallel with the secondary impedance reduction circuit of the adjacent preceding-stage secondary delay protection circuit; the suppression circuit includes an inductor for suppressing the initial current rise of the load device.

2. The high-voltage arc suppression circuit according to claim 1, characterized in that, The suppression circuit includes an air-core inductor and / or a magnetic-core inductor.

3. The high-voltage arc suppression circuit according to claim 1, characterized in that, The delay switching circuit includes at least one overvoltage delay breakdown element; the conduction time of the overvoltage delay breakdown element is less than the volt-second product saturation time of the inductance of the suppression circuit.

4. The high-voltage arc suppression circuit according to claim 3, characterized in that, The overvoltage delay breakdown element includes a gas discharge tube and / or a varistor.

5. The high-voltage arc suppression circuit according to claim 1, characterized in that, The impedance reduction circuit includes a resistor and / or an inductor.

6. The high-voltage arc suppression circuit according to claim 5, characterized in that, The impedance reduction circuit includes one or more of the following: pure resistor, pure inductor, inductive resistor, and resistive inductor.

7. The high-voltage arc suppression circuit according to claim 1, characterized in that, The impedance of the impedance reduction circuit described in the subsequent stage is less than the impedance of the impedance reduction circuit described in the preceding stage.

8. The high-voltage arc suppression circuit according to claim 1, characterized in that, The suppression circuit and the delay protection circuit are connected in parallel; the delay protection circuit includes a first delay protection circuit and a second delay protection circuit; the first delay protection circuit includes a first delay switching circuit and a first impedance reduction circuit connected in series; the second delay protection circuit includes a second delay switching circuit and a second impedance reduction circuit connected in series. The second delay protection circuit is connected in parallel with the first impedance reduction circuit, and the first delay protection circuit is connected in parallel with the suppression circuit.

9. A high-voltage power supply device, characterized in that, The high-voltage power supply equipment includes a power supply body, an overvoltage protection device, and a high-voltage arc suppression circuit as described in any one of claims 1 to 8. The power supply body supplies power to the load device through the high-voltage arc suppression circuit. The overvoltage protection device is used to control the connection between the power supply body and the load device to be disconnected when the load voltage exceeds a preset threshold.

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