Direct-current power supply specially used for heating submerged arc furnace

Abstract

The utility model discloses a direct-current power supply specially used for heating a submerged arc furnace, which comprises a vacuum circuit breaker, a voltage-regulating rectifier transformer, silicon controlled rectifier components, a smoothing reactor and a PLC (programmable logic controller) control system, the vacuum circuit breaker is connected with the voltage-regulating rectifier transformer, and a plurality of groups of silicon controlled rectifier components connected in parallel are connected behind the voltage-regulating rectifier transformer. The smoothing reactor is connected behind the silicon controlled rectifier assembly, the smoothing reactor is connected with the direct-current power supply controller through the signal isolation converter, and the direct-current power supply controller is connected with the PLC control system. The DC power supply can eliminate the problems of reactance drop, skin effect, inter-electrode interference effect and the like, and is low in operation loss and high in electric efficiency.

Description

Technical Field

[0001] The utility model belongs to the technical field of power supply, and in particular relates to a direct current power supply specially used for heating a submerged arc furnace. Background Art

[0002] Submerged arc furnace is an essential equipment for smelting ferrosilicon, ferronickel, ferrochrome and calcium carbide in the ferroalloy industry. For a long time, most domestic submerged arc furnaces have adopted AC power supply, which has led to low power factor, difficulty in controlling the balance of the three-phase power grid, low efficiency, high operating cost and other problems that have not been solved. DC power supply has the advantages of high stability, high efficiency, high control accuracy and good safety, and is suitable for occasions that require precise control of heating temperature or heating rate. However, there is currently no DC power supply dedicated to heating of submerged arc furnaces. Summary of the invention

[0003] The utility model aims to provide a DC power supply specially used for heating a submerged arc furnace. The DC power supply is specially used for heating a submerged arc furnace, has low operation loss and high electrical efficiency.

[0004] A DC power supply specially used for heating an ore-fired furnace comprises a vacuum circuit breaker, a voltage-regulating rectifier transformer, a thyristor rectifier assembly, a smoothing reactor and a PLC control system. The vacuum circuit breaker is connected to the voltage-regulating rectifier transformer, a plurality of parallel thyristor rectifier assemblies are connected to the voltage-regulating rectifier transformer, a smoothing reactor is connected to the thyristor rectifier assembly, the smoothing reactor is connected to a DC power supply controller via a signal isolation converter, and the DC power supply controller is connected to the PLC control system.

[0005] Furthermore, the voltage regulating rectifier transformer adopts a pulse voltage regulating rectifier transformer.

[0006] Furthermore, the transformer and the thyristor rectifier assembly are cooled by a water cooling system.

[0007] Furthermore, the control module of the water-cooling system is connected to a PLC control system.

[0008] The utility model direct current power supply can eliminate the problems of reactance voltage drop, skin effect, interference effect between electrodes and the like, and has low operation loss and high electrical efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a structural schematic diagram of the utility model. DETAILED DESCRIPTION

[0010] like Figure 1As shown, the present embodiment provides a DC power supply specifically used for heating an electric arc furnace, including a vacuum circuit breaker, a voltage regulating rectifier transformer, a thyristor rectifier assembly, a smoothing reactor and a cooling system. The vacuum circuit breaker is connected to the voltage regulating rectifier transformer. The voltage regulating rectifier transformer adopts a 12-pulse voltage regulating rectifier transformer. Twelve groups of parallel rectifier cabinets are connected behind the voltage regulating rectifier transformer. The rectifier cabinet includes a rectifier unit, a protection circuit and a DC power supply. The rectifier unit includes two groups of thyristor rectifier circuits. The input end of the rectifier circuit is connected to the voltage regulating rectifier transformer, and the output end is connected to the smoothing reactor. The voltage and current output by the smoothing reactor are connected to the DC power supply controller through the signal isolation converter KL, and the DC power supply controller is connected to the PLC control system.

[0011] The transformer and the rectifier cabinet are cooled by a water cooling system, and a control module of the water cooling system is connected to a PLC control system.

[0012] The output voltage and current of the rectifier cabinet are converted by the signal isolation converter and sent to the DC power supply controller to achieve constant voltage, constant current and constant power control of the power supply. The DC power supply has local / remote control functions. The voltage regulation process is first roughly adjusted by the transformer, and then fine-tuned by the thyristor phase control. The monitoring and control signals required for the transformer water cooling circuit and the rectifier pure water cooling circuit are connected to the PLC system and centrally controlled by the PLC.

[0013] The above is only a preferred implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any modification and replacement based on the technical solution and utility model concept provided by the present invention should be included in the protection scope of the present invention.

Claims

1. A DC power supply specially used for heating a submerged arc furnace, characterized in that: The invention comprises a vacuum circuit breaker, a voltage regulating rectifier transformer, a thyristor rectifier assembly, a smoothing reactor and a PLC control system. The vacuum circuit breaker is connected to the voltage regulating rectifier transformer, a plurality of parallel thyristor rectifier assemblies are connected to the voltage regulating rectifier transformer, a smoothing reactor is connected to the thyristor rectifier assembly, the smoothing reactor is connected to a DC power supply controller through a signal isolation converter, and the DC power supply controller is connected to the PLC control system.

2. A DC power supply specifically used for heating a submerged arc furnace according to claim 1, characterized in that: The voltage regulating rectifier transformer adopts a pulse voltage regulating rectifier transformer.

3. A DC power supply dedicated to heating a submerged arc furnace according to claim 1, characterized in that: The transformer and the thyristor rectifier assembly are cooled by a water cooling system.

4. A DC power supply specifically used for heating a submerged arc furnace according to claim 3, characterized in that: The control module of the water-cooling system is connected to the PLC control system.

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