Auxiliary power supply for protection device in 380V power distribution system

Abstract

According to the auxiliary power supply for the protection device in the 380V power distribution system, a special auxiliary power supply module is additionally arranged on a typical wiring diagram of an original 380V motor, the input end is connected with a local three-phase alternating-current power supply and outputs direct-current 220V or alternating-current 220V, and when any two-phase alternating-current power supply on the alternating-current side is interrupted, the stable direct-current 220V or alternating-current 220V power supply can still be output. In order to thoroughly eliminate the traditional 380V alternating current power distribution system, the auxiliary power supply device is connected to the original 380V alternating current power distribution system, so that the motor protector or the comprehensive protection device can still supply power normally when the 380V alternating current power distribution system is subjected to single-phase grounding or two-phase interphase grounding short circuit.

Description

TECHNICAL FIELD

[0001] The utility model relates to 380V AC power distribution system field especially, it is a kind of auxiliary power supply for 380V distribution system protection device. BACKGROUND

[0002] The use background of protection device auxiliary power supply is usually related to ensuring the stability and reliability of power system.In critical fields such as industrial automation, power system, data center, auxiliary power supply system is essential. They provide necessary power support when the main power fails, ensure the continuity of critical operations, prevent potential disturbances and data loss. In addition, auxiliary power supply is also responsible for providing stable voltage output, which is crucial for sensitive electronic equipment in protection devices, which can prevent voltage fluctuation-induced failures, data corruption or physical damage. In BBU (Battery Backup Unit), auxiliary power supply system supports a series of active protection measures, including overvoltage, overcurrent and short circuit protection, and temperature monitoring, etc., by continuously checking various parameters in real time, to ensure a quick response to abnormalities or problems, thereby improving the overall safety of the system

[0003] Currently, the protection device auxiliary power supply of 380V AC power distribution system in power plants or chemical plants has the following problems: In order to simplify the design of traditional 380V AC power distribution system motor protection power supply, motor protectors or comprehensive protection devices are generally powered by local single-phase or two-phase AC power supply. When single-phase grounding or two-phase interphase grounding short circuit occurs, there is a problem that the protection device may fail to operate due to power loss (or under-voltage).

[0004] Therefore, the present application aims to develop a protection device auxiliary power supply that can still provide normal power supply to motor protectors or comprehensive protection devices when single-phase grounding or two-phase interphase grounding short circuit occurs. UTILITY MODEL CONTENT

[0005] The technical problem to be solved by the present application is that in the traditional design, when single-phase grounding or two-phase interphase grounding short circuit occurs, there is a problem that the protection device may fail to operate due to power loss (or under-voltage).

[0006] To address the aforementioned technical problems, this application provides an auxiliary power supply for a protection device in a 380V power distribution system, comprising: an input terminal connected to local A-phase, B-phase, and C-phase three-phase AC power and a neutral line, wherein each phase of AC power is connected to its respective rectifier through a current transformer, the current transformer detects the current of its connected phase and sends a signal to the protection device; a filter circuit connected to the output terminal of the rectifier, the output terminal of the filter circuit being connected to a voltage regulator circuit to provide a stable DC output; an inverter connected to the output terminal of the voltage regulator circuit to provide AC power output; an output terminal connected to the power supply terminal of the protection device, the output terminal outputting stable DC or AC power, the AC power output terminal being connected to the inverter, and the DC power output terminal being connected to the voltage regulator circuit of the filter circuit.

[0007] According to an embodiment of this application, the current transformer is a 1.0A current transformer used for current detection.

[0008] According to an embodiment of this application, the input terminal is connected to a local three-phase AC power supply, and the output terminal outputs a stable DC or AC 220V power supply.

[0009] According to an embodiment of this application, the load is powered by a 24VDC / 230VAC low-power power inverter.

[0010] According to an embodiment of this application, the protection device is communicatively connected to a current transformer.

[0011] According to an embodiment of this application, the inverter is disposed inside an inverter box.

[0012] According to an embodiment of this application, the filter circuit includes a capacitor for smoothing the waveform of the current.

[0013] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0014] 1. This power supply unit detects current through a current transformer, converts AC to DC through a rectifier, provides a stable DC output through a filter and voltage regulator circuit, and converts DC back to AC through an inverter. Finally, it provides +DC220V and ~AC220V power through the output terminal. This design can provide a stable power supply for the protection device and ensure its normal operation.

[0015] 2. The auxiliary power supply of this application is simple to manufacture, easy to use, and highly practical. It is specifically designed for use in traditional 380V AC power distribution systems. The input terminal is connected to the local three-phase AC power supply, and the output terminal is connected to the power supply terminal of the protection device. If the original protection device power supply can be powered by either AC or DC power, the auxiliary power supply is used to provide DC 220V output power. If the original protection device power supply can only be powered by AC power, the auxiliary power supply is used to provide AC 220V output power, thereby providing a reliable power supply for the protection device. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings of the embodiments will be briefly described below. Obviously, the drawings described below only relate to some embodiments of this application, and are not intended to limit this application.

[0017] Figure 1 This is a schematic diagram illustrating the composition of an auxiliary power supply for a protection device in a 380V power distribution system, as an example of this utility model. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the described embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application pertains. The terms “first,” “second,” and similar terms used in the specification and claims of this patent application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a,” and similar terms, do not indicate a limitation of quantity, but rather indicate the presence of at least one.

[0020] like Figure 1As shown in the illustration, this utility model provides an auxiliary power supply for a protection device in a 380V power distribution system. A dedicated auxiliary power supply module is added to the existing typical wiring diagram of a 380V motor. The input terminal is connected to a local three-phase AC power supply, and the output is either DC 220V or AC 220V. Even if any two phases of the AC power supply on the AC side are interrupted, a stable DC or AC 220V power supply can still be guaranteed. This application aims to completely eliminate the traditional 380V AC power distribution system by using an auxiliary power supply device connected to the original 380V AC power distribution system. This ensures that the motor protector or integrated protection device can still supply power normally in the event of a single-phase ground fault or a two-phase short circuit in the 380V AC power distribution system.

[0021] In this embodiment, the input terminal is connected to the local three-phase AC power of phase A, phase B, and phase C and the neutral line. Each phase of AC power is connected to its respective rectifier through its own current transformer. The current transformer detects the current of the phase it is connected to and sends the signal to the protection device.

[0022] Specifically, the current transformer is a 1.0A current transformer used for current detection.

[0023] Specifically, the protection device is communicatively connected to the current transformer.

[0024] In this embodiment, the filter circuit is connected to the output terminal of the rectifier, and the output terminal of the filter circuit is connected to the voltage regulator circuit to provide a stable DC output.

[0025] Specifically, the filter circuit includes capacitors for smoothing the waveform of the current.

[0026] In this embodiment, the inverter is connected to the output terminal of the voltage regulator circuit to provide AC power output.

[0027] Specifically, the inverter is installed inside the inverter box.

[0028] In this embodiment, the output terminal is connected to the power supply terminal of the protection device, and the output terminal outputs stable DC or AC power. The AC power output terminal is connected to the inverter, and the DC power output terminal is connected to the voltage regulation circuit of the filter circuit.

[0029] Specifically, the input terminal is connected to a local three-phase AC power supply, and the output terminal outputs a stable DC or AC 220V power supply.

[0030] Specifically, the output provides power to the load, which is powered by a 24VDC / 230VAC low-power power inverter.

[0031] like Figure 1As shown, in this embodiment, the auxiliary power supply of the protection device includes: Input terminal (IN): Three-phase AC input: phase A, phase B, phase C and neutral line (N); Current transformer: Each phase (phase A, phase B, phase C) has a 1.0A current transformer for current detection, and the three-phase AC power is connected to its respective rectifier through the current transformer; Rectifier (AC-DC): Each phase has a rectifier that converts AC power to DC power and connects to the filtering and voltage regulation circuit; Filtering and voltage regulation circuit: The rectified DC power is filtered and regulated by the filtering and voltage regulation circuit to provide a stable DC output; Inverter (DC-AC): The inverter converts DC power back to AC power and outputs it to the load; Output terminal (OUT): Provides +DC220V and ~AC220V power.

[0032] This embodiment describes the working principle of an auxiliary power supply for a protection device in a 380V power distribution system:

[0033] Current transformers detect the current in each phase and send signals to protection devices; alternating current (AC) is converted to direct current (DC) by a rectifier. The rectifier, typically composed of a diode bridge, converts the positive and negative half-cycles of AC into unidirectional DC; the rectified DC is then smoothed by a filter circuit (such as a capacitor) and provides a stable DC output through a voltage regulator circuit; the DC is then converted back to AC by an inverter. The inverter, typically composed of electronic switches (such as IGBTs or MOSFETs), generates AC by controlling the frequency and duty cycle of the switches. The AC output from the inverter and the filtered DC output are then supplied to the load through their respective output terminals.

[0034] Specifically, the auxiliary power supply of this application is added to the original typical wiring of a 380V motor. The power supply wiring of the original motor protector or integrated protection device is disconnected. The input terminal of the auxiliary power supply module is connected to the local three-phase AC power supply, and the output terminal is connected to the power supply terminal of the original motor protector or integrated protection device. If the original motor protector or integrated protection device can be powered by either AC or DC power, the auxiliary power supply module's DC 220V output is used for power supply. If the original motor protector or integrated protection device can only be powered by AC power, the auxiliary power supply module's AC 220V output is used for power supply.

[0035] In summary, the technical solution of this application has the following beneficial effects:

[0036] 1. This power supply unit detects current through a current transformer, converts AC to DC through a rectifier, provides a stable DC output through a filter and voltage regulator circuit, and converts DC back to AC through an inverter. Finally, it provides +DC220V and ~AC220V power through the output terminal. This design can provide a stable power supply for the protection device and ensure its normal operation.

[0037] 2. The auxiliary power supply of this application is simple to manufacture, easy to use, and highly practical. It is specifically designed for use in traditional 380V AC power distribution systems. The input terminal is connected to the local three-phase AC power supply, and the output terminal is connected to the power supply terminal of the protection device. If the original protection device power supply can be powered by either AC or DC power, the auxiliary power supply is used to provide DC 220V output power. If the original protection device power supply can only be powered by AC power, the auxiliary power supply is used to provide AC 220V output power, thereby providing a reliable power supply for the protection device.

[0038] The above are merely exemplary embodiments of this application and are not intended to limit the scope of protection of this application, which is determined by the appended claims.

Claims

1. An auxiliary power supply for a protective device in a 380 V power distribution system, characterized in that, Comprise: Input end, connect the three-phase alternating current of A phase, B phase, C phase and neutral line, each phase alternating current is connected to the respective rectifier through the respective current transformer, the current transformer detects the current of the phase connected and sends the signal to the protection device; Filter circuit, connect the output end of the rectifier, the output end of the filter circuit is connected to the voltage stabilizing circuit, providing stable DC output; Inverter, connected to the output end of the voltage stabilizing circuit, providing AC output Output end, connect the power supply end of the protection device, the output end outputs stable DC or AC, the AC output end is connected to the inverter, and the DC output end is connected to the voltage stabilizing circuit of the filter circuit.

2. An auxiliary power supply for a protective device in a 380V power distribution system according to claim 1, characterized in that, The current transformer is a 1.0A current transformer for detecting current.

3. An auxiliary power supply for a protective device in a 380V power distribution system according to claim 1, characterized in that, The input end connects the three-phase alternating current power supply, and the output is DC 220V or AC 220V, and the output end outputs stable DC or AC 220V power supply.

4. An auxiliary power supply for protection devices in a 380V power distribution system according to claim 1, characterized in that, The power supply of the load is provided by a 24VDC / 230VAC low-power power inverter.

5. An auxiliary power supply for protection devices in 380V distribution systems according to claim 1, characterized in that, The protection device is in communication connection with the current transformer.

6. An auxiliary power supply for protection devices in 380V distribution systems according to claim 1, characterized in that, The inverter is arranged in the inverter box.

7. An auxiliary power supply for protection devices in 380V distribution systems according to claim 1, characterized in that, The filter circuit includes a capacitor for smoothing the waveform of the current.

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