Polysilicon power cabinet control system capable of inhibiting sharp voltage

Abstract

This invention addresses the problems in existing power cabinets where voltage spikes during voltage testing cause trigger board burnout and thyristor malfunctions leading to circulating current within the cabinet. It provides a polycrystalline silicon power cabinet control system capable of suppressing voltage spikes. The system includes: a trigger circuit, a controller, and six trigger boards. The trigger circuit connects to the mains input, converting the mains voltage into a control voltage acceptable to the power cabinet. Each trigger board has two pairs of output terminals, each pair connecting to the gate and cathode of the thyristor in the corresponding power cabinet position. Each trigger board also has two pairs of input terminals, each pair connected to the trigger circuit via an isolation transformer. The isolation transformer prevents voltage spikes generated by the thyristors in the power cabinet during voltage testing from entering the trigger circuit. Each pair of output terminals is connected via clamping elements to protect the thyristors in the power cabinet from being burned out by voltage spikes.

Description

Technical Field

[0001] This utility model relates to the field of polycrystalline silicon reduction power supply technology, and in particular to a polycrystalline silicon power cabinet control system that can suppress voltage spikes. Background Technology

[0002] Chinese patent (title: A polycrystalline silicon reduction power supply and its control method, announcement number: CN116707321B, announcement date: 20231013) discloses a polycrystalline silicon reduction power supply, which mainly includes a main transformer, a power control component, an adjustment component, a step-up transformer, a holding switch, a breakdown switch, a protection switch, a pressure-reducing switch, a switching switch, and a main switch.

[0003] However, in this polysilicon reduction power supply system, during power cabinet voltage suppression, the thyristors in the power cabinet generate voltage spikes. These spikes are transmitted to the secondary coil through the primary coil of the voltage suppression transformer, then fed back to the primary coil, and finally conducted to the gate and cathode of the thyristors in the power cabinet. This phenomenon will cause the trigger board to burn out and the thyristors to conduct incorrectly, resulting in circulating current within the cabinet. These voltage spikes not only burn out the fast-melting circuit and the thyristors, but also severely affect the normal operation of the reduction furnace, thus threatening the stability and safety of the production process. Utility Model Content

[0004] This invention addresses the problem in existing technologies where voltage spikes during power cabinet voltage suppression cause trigger board burnout and thyristor malfunctions leading to circulating current within the cabinet. It provides a polycrystalline silicon power cabinet control system capable of suppressing voltage spikes.

[0005] The technical solution adopted in this utility model is:

[0006] A polycrystalline silicon power cabinet control system capable of suppressing voltage spikes includes:

[0007] The trigger circuit is connected to the mains input and converts the mains voltage into a control voltage acceptable to the power cabinet.

[0008] Controller;

[0009] There are 6 trigger boards, each with two pairs of output terminals. Each pair of output terminals connects to the gate and cathode of the thyristor in the power cabinet of the corresponding gear. The power cabinet has the following gears: high-start gear 1, gear 1, gear 2, gear 3, gear 4, and gear 5. Each trigger board has two pairs of input terminals, each pair of input terminals is connected to the trigger circuit through an isolation transformer. The isolation transformer is used to prevent the voltage spikes generated by the thyristors in the power cabinet during the voltage-down process from entering the trigger circuit, thereby preventing the voltage spikes from entering the power cabinets of other gears.

[0010] Each pair of output terminals is connected by a clamping element. Since each pair of output terminals connects to the gate and cathode of the thyristor in the power cabinet corresponding to the position, the clamping element is connected in parallel between the gate and cathode of the thyristor to protect the thyristor in the power cabinet from being burned out by voltage spikes.

[0011] Furthermore, a transient voltage suppressor (TVS) is selected as the clamping element.

[0012] Furthermore, the maximum clamping voltage of the transient voltage suppressor (TVS) is not less than 10.5V.

[0013] Furthermore, contactors are connected in series between the trigger circuits corresponding to the first-level power cabinet and the second-level, third-level, fourth-level, and fifth-level power cabinets. The contactors are disconnected during the pressure test and closed after the pressure test is completed. This is to further prevent the spike voltage generated by the thyristor in the power cabinet during the pressure test from being transmitted to the trigger circuits and then to the second-level, third-level, fourth-level, and fifth-level power cabinets.

[0014] Furthermore, each trigger board has two control terminals, each of which is connected to the controller. Each control terminal receives control signals from the controller to control the voltage of the two pairs of output terminals, thereby controlling the conduction of the thyristors in the power cabinet.

[0015] Furthermore, the clamping element is a metal oxide varistor (MOV), which is directly connected in parallel across the protected line without needing to consider polarity.

[0016] Furthermore, when using a Zener diode as the clamping element, it is essential to ensure that the Zener diode is reverse biased.

[0017] Furthermore, the maximum clamping voltage of the Zener diode is not less than 10.5V.

[0018] Furthermore, the clamping element is a bidirectional trigger diode DIAC, which conducts symmetrically in both directions.

[0019] Furthermore, the maximum clamping voltage of the bidirectional trigger diode DIAC is not less than 10.5V.

[0020] The beneficial effects of this utility model are:

[0021] The isolation transformer in the polycrystalline silicon power cabinet control system disclosed in this utility model can block the propagation of voltage spikes between different components. Clamping elements are connected in parallel between the thyristor gate and cathode to limit voltage peaks, prevent damage to the thyristor, extend equipment life, provide safe and stable power support for polycrystalline silicon reduction, reduce production costs, and improve production efficiency. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of a polysilicon power cabinet control system that can suppress voltage spikes. Detailed Implementation

[0024] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0025] The following disclosure provides many different embodiments or examples for implementing various structures of this invention. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this invention.

[0026] The embodiments of the utility model will now be described in detail with reference to the accompanying drawings.

[0027] As attached Figure 1As shown, the polysilicon power cabinet control system for suppressing voltage spikes provided in this embodiment includes the following components: trigger circuit 1, controller, and six trigger boards 3. In addition to the complete structure, this embodiment also provides a mains input of 220V to power the polysilicon power cabinet control system for suppressing voltage spikes. Specifically, trigger circuit 1 is connected to the mains input, and trigger circuit 1 converts the mains voltage into a control voltage acceptable to the power cabinet through a step-down transformer T1; trigger circuit 1 powers each trigger board 3. Each trigger board 3 has two pairs of output terminals 31 (corresponding to two thyristors V1 in each power cabinet position), and each pair of output terminals 31 connects to the gate and cathode of the thyristor V1 in the corresponding power cabinet position; wherein, the power cabinets in the external components have the following positions: high-start first-level power cabinet 20, first-level power cabinet 21, second-level power cabinet 22, third-level power cabinet 23, fourth-level power cabinet 24, and fifth-level power cabinet 25, with two thyristors V1 in each power cabinet position.

[0028] The circuit structure of the external components in this embodiment is consistent with the figures in the specification of Chinese Patent (Title: A Polycrystalline Silicon Reduction Power Supply and Its Control Method, Publication No.: CN116707321B, Publication Date: 20231013). Figure 1 The same applies, except that "power control unit" is replaced with "power cabinet" in this embodiment, and "thyristor" in "power control unit" is replaced with "silicon controlled rectifier" in this embodiment.

[0029] The following section describes the connections between the components.

[0030] Each trigger board 3 has two pairs of input terminals 32. Each pair of input terminals 32 is connected to the trigger circuit 1 through an isolation transformer T2 to receive the power supply voltage of the trigger circuit. The isolation transformer T2 can prevent the spike voltage generated by the thyristor V1 in the power cabinet during the voltage-down process from entering the trigger circuit 1, thereby preventing the spike voltage from entering the power cabinet of other positions.

[0031] Each pair of output terminals 31 is connected by a clamping element. Since each pair of output terminals 31 is connected to the gate and cathode of the thyristor V1 in the power cabinet of the corresponding position, it is equivalent to the clamping element being connected in parallel between the gate and cathode of the thyristor V1, which can protect the thyristor V1 in the power cabinet from being burned out by peak voltage.

[0032] The beneficial effects of the above technical solution are as follows: the isolation transformer T2 blocks the propagation path of the peak voltage between different components, the clamping element is connected in parallel between the gate and cathode of the thyristor V1 to limit the voltage peak, prevent damage to the thyristor V1, extend the equipment life, provide safe and stable power support for polysilicon reduction, reduce production costs, and improve production efficiency.

[0033] Furthermore, in this embodiment, the clamping element is a transient voltage suppressor (TVS) of model P4KE6.8CA, which is packaged in D0-41. The TVS in this package is a bidirectional TVS diode with a peak pulse current of 38.1A, a maximum clamping voltage of 10.5V, and a reverse cutoff voltage of 5.8V.

[0034] Furthermore, a contactor KM is connected in series between the trigger circuits 1 corresponding to the first-level power cabinets 20 and 21 in the external components and the trigger circuits 1 corresponding to the second-level power cabinets 22, 23, 24, and 25, to electrically isolate the trigger circuits of different levels. Contactor KM is disconnected during the pressurization process and closed after the pressurization is completed, further preventing the voltage spikes generated by the thyristor V1 in the power cabinets during the pressurization process from being transmitted to trigger circuit 1 and then to the second-level power cabinets 22, 23, 24, and 25.

[0035] Furthermore, each trigger board 3 has two control terminals 30, each of which is connected to the controller. Each control terminal 30 receives control signals from the controller to control the voltage of the two pairs of output terminals 31, thereby controlling the conduction of the thyristor V1 in the power cabinet. In this embodiment, a PLC is selected as the controller.

[0036] Trigger board 3 is a printed circuit board, internally integrating a rectifier circuit, a filter circuit, a step-down circuit, and a switching chip. The control signal received from the controller at control terminal 30 is transmitted to the switching chip to control the on / off state of the switching chip, thereby controlling the on / off state of the thyristor V1. The step-down circuit outputs a constant voltage, while the switching chip outputs a controllable square wave voltage. This controllable square wave voltage is applied to the gate and cathode of the thyristor V1 to control its on / off state.

[0037] Furthermore, each trigger board has two control terminals, each of which is connected to the controller. Each control terminal receives control signals from the controller to control the voltage of the two pairs of output terminals, thereby controlling the conduction of the thyristors in the power cabinet.

[0038] Furthermore, the clamping element is a metal oxide varistor (MOV), which is directly connected in parallel across the protected line without needing to consider polarity.

[0039] Furthermore, when using a Zener diode as the clamping element, it is essential to ensure that the Zener diode is reverse biased.

[0040] Furthermore, the maximum clamping voltage of the Zener diode is not less than 10.5V.

[0041] Furthermore, the clamping element is a bidirectional trigger diode DIAC, which conducts symmetrically in both directions.

[0042] Furthermore, the maximum clamping voltage of the bidirectional trigger diode DIAC is not less than 10.5V.

Claims

1. A polycrystalline silicon power cabinet control system capable of suppressing voltage spikes, characterized in that, include: The trigger circuit is connected to the mains input and converts the mains voltage into a control voltage acceptable to the power cabinet. Controller; There are 6 trigger boards, each connected to the controller. Each trigger board has two pairs of output terminals, and each pair of output terminals connects to the gate and cathode of the thyristor in the power cabinet of the corresponding gear. The power cabinet has the following gears: high-start gear 1, gear 1, gear 2, gear 3, gear 4, and gear 5. Each trigger board has two pairs of input terminals, and each pair of input terminals is connected to the trigger circuit through an isolation transformer. The isolation transformer is used to prevent the voltage spikes generated by the thyristors in the power cabinet during the voltage-down process from entering the trigger circuit, thereby preventing the voltage spikes from entering the power cabinets of other gears. Each pair of output terminals is connected by a clamping element to protect the thyristors in the power cabinet from being burned out by voltage spikes.

2. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to claim 1, characterized in that, The clamping element is a transient voltage suppressor (TVS).

3. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to claim 2, characterized in that, The maximum clamping voltage of the transient voltage suppressor (TVS) is not less than 10.5V.

4. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to claim 1, characterized in that, A contactor is connected in series between the trigger circuits of the first-level power cabinet and the trigger circuits of the second-level, third-level, fourth-level, and fifth-level power cabinets to further prevent the spike voltage generated by the thyristor in the power cabinet during the pressure test from being transmitted to the trigger circuits and then to the second-level, third-level, fourth-level, and fifth-level power cabinets.

5. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to any one of claims 1-4, characterized in that, Each trigger board also has two control terminals. Each control terminal is connected to the controller. Each control terminal receives control signals from the controller to control the voltage of the two pairs of output terminals, thereby controlling the conduction of the thyristors in the power cabinet.

6. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to claim 1, characterized in that, The clamping element is a metal oxide varistor (MOV). The MOV is directly connected in parallel across the protected line, and polarity does not need to be considered.

7. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to claim 1, characterized in that, The clamping element is a Zener diode, and it is important to ensure that the Zener diode is reverse biased.

8. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to claim 7, characterized in that, The maximum clamping voltage of a Zener diode is not less than 10.5V.

9. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to claim 1, characterized in that, The clamping element is a bidirectional trigger diode DIAC, which conducts symmetrically in both directions.

10. The polycrystalline silicon power cabinet control system capable of suppressing voltage spikes according to claim 9, characterized in that, The maximum clamping voltage of the bidirectional trigger diode DIAC is not less than 10.5V.

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