CN117405967A

CN117405967A - Integrated three-phase current monitoring system

Info

Publication number: CN117405967A
Application number: CN202311588511.5A
Authority: CN
Inventors: 张凤雏; 张志宝; 许文专; 张磊; 顾益刚; 蒋科慧
Original assignee: Jiangyin Sfere Electric Co ltd
Current assignee: Jiangyin Sfere Electric Co ltd
Priority date: 2023-11-27
Filing date: 2023-11-27
Publication date: 2024-01-16
Anticipated expiration: 2043-11-27
Also published as: CN117405967B

Abstract

The integrated three-phase current monitoring system of the invention comprises: the main module wire inlet end is connected with the molded case circuit breaker wire outlet end, the main module wire outlet end is connected with the electric equipment power supply end, the display module is electrically connected with the main module through the connecting wire, and the main module is electrically connected with the audible and visual alarm; the main module includes: the built-in three-phase current measuring circuit measures the current of each phase loop and converts the alternating current of each phase into an alternating current signal of several hundred amperes; the SOC metering circuit meters the current of each phase of loop, transmits three-phase current parameters to the remote monitoring system through the isolation RS485 circuit, and outputs data information of the three-phase current parameters exceeding a set current parameter threshold range through an alarm circuit and an audible and visual alarm; the switching power supply circuit provides working power supply for the main module and the display module; the display module is used for communicating with the main module data and displaying the three-phase current parameters in situ.

Description

Integrated three-phase current monitoring system

Technical Field

The invention relates to the technical field of current detection, in particular to an integrated three-phase current monitoring system.

Background

In the existing low-voltage power distribution cabinet, an external current transformer is arranged in an outlet end loop of each molded case circuit breaker to measure current of each phase loop, and the current is connected to a three-phase current input terminal of a three-phase ammeter on a front panel of the low-voltage power distribution cabinet through a secondary side output terminal wiring of the external current transformer so as to monitor three-phase current of the loop; when a plurality of molded case circuit breaker loops are configured for each low-voltage power distribution cabinet, the following problems generally exist: 1) The number of the installed external current transformers is too large, so that the layout of electrical components in the power distribution cabinet is inconvenient; 2) The secondary side output connecting wires of the external current transformer are more, the manual wiring assembly time is longer, and the processing efficiency is low; 3) And the low-voltage power distribution cabinet is inconvenient to overhaul and maintain in the later period.

Disclosure of Invention

The invention provides an integrated three-phase current monitoring system aiming at the problems and the defects existing in the prior art.

The invention solves the technical problems by the following technical proposal:

the invention provides an integrated three-phase current monitoring system which is characterized by comprising a main module, a display module, a connecting wire and an audible and visual alarm, wherein the incoming line end of the main module is connected with the outgoing line end of a molded case circuit breaker, the outgoing line end of the main module is connected with the power supply end of electric equipment, the main module is arranged right below the outgoing line end of the molded case circuit breaker in a low-voltage power distribution cabinet, the display module is arranged on the front panel of the low-voltage power distribution cabinet in an embedded manner, the display module is electrically connected with the main module through the connecting wire, and the main module is electrically connected with the audible and visual alarm;

The main module comprises a built-in three-phase current measuring circuit, an SOC metering circuit, an alarm circuit, an isolation RS485 circuit and a switching power supply circuit;

the built-in three-phase current measuring circuit is used for measuring the current of each phase loop and converting the alternating current of each phase into an alternating current signal of a few hundred amperes; the SOC metering circuit is used for metering the current of each phase of loop, transmitting three-phase current parameters to the remote monitoring system through the isolation RS485 circuit, and outputting data information of the three-phase current parameters exceeding a set current parameter threshold range through the alarm circuit and the audible-visual alarm; the switching power supply circuit provides working power supply for the main module and the display module; the display module is used for carrying out data communication with the main module and carrying out on-site display on three-phase current parameters; the connecting wire is used for realizing the working power supply and the data communication line provided by the main module to the display module.

The invention has the positive progress effects that:

according to the integrated three-phase current monitoring system provided by the invention, the three-phase current transformer is integrated in the monitoring system, the maximum measurement current can reach AC630A, no external current transformer is required to be installed, the installation space in the low-voltage power distribution cabinet can be greatly optimized, and the layout of electrical elements is convenient; the secondary wiring of the external current transformer is saved, the processing efficiency is improved, the production cost is reduced, and the later maintenance and detection of the power distribution cabinet are also facilitated.

Drawings

Fig. 1 is a block diagram of an integrated three-phase current monitoring system.

Fig. 2 is a diagram of a built-in three-phase current measurement circuit and SOC metering circuit in an integrated three-phase current monitoring system.

Fig. 3 is a circuit diagram of a warning circuit in an integrated three-phase current monitoring system.

Fig. 4 is a circuit diagram of a isolated RS485 circuit in an integrated three-phase current monitoring system.

Fig. 5 is a circuit diagram of a switching power supply in an integrated three-phase current monitoring system.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

As shown in fig. 1-5, the embodiment provides an integrated three-phase current monitoring system, and an internal integrated three-phase ac current transformer can save an external current transformer, facilitate layout of electrical elements in a power distribution cabinet, improve processing efficiency, and reduce production cost.

As shown in fig. 1, the integrated three-phase current monitoring system comprises a main module 1, a display module 2, a connecting wire 3 and an audible and visual alarm 4, wherein the incoming wire end of the main module 1 is connected with the outgoing wire end of a molded case circuit breaker, the outgoing wire end of the main module 1 is connected with the power supply end of electric equipment, the main module 1 is arranged right below the outgoing wire end of the molded case circuit breaker in a low-voltage power distribution cabinet, the display module 2 is arranged on the front panel of the low-voltage power distribution cabinet in an embedded mode, the display module 2 is electrically connected with the main module 1 through the connecting wire 3, and the main module 1 is electrically connected with the audible and visual alarm 4.

The working power supply of the display module 2 is provided by a DC12V power supply output by the main module 1, the display module 2 is in data communication with the main module 1 through a connecting wire 3 and a non-isolated RS485 circuit in the main module 1, the connecting wire 3 is a 6-core RJ11 connecting wire, an MCU in a display circuit on the display module 2 controls a data receiving and transmitting function of the non-isolated RS485 circuit through a serial port, and the MCU controls a display driving chip in the display circuit to display three-phase current data on site, wherein the display circuit comprises LED display and LCD display.

The main module 1 comprises a built-in three-phase current measuring circuit 101, an SOC metering circuit 102, an alarm circuit 103, an isolation RS485 circuit 104 and a switching power supply circuit 105.

The built-in three-phase current measuring circuit 101 is used for measuring the loop current of each phase and converting the alternating current of each phase into an alternating current signal of several hundred amperes; the SOC metering circuit 102 is used for metering the current of each phase loop, transmitting three-phase current parameters to the remote monitoring system 5 through the isolation RS485 circuit 104, and outputting data information of the three-phase current parameters exceeding a set current parameter threshold range through the alarm circuit 103 and the audible and visual alarm 4; the switching power supply circuit 105 supplies the main module 1 and the display module 2 with operating power; the display module 2 is used for carrying out data communication with the main module 1 and carrying out on-site display on three-phase current parameters; the connection line 3 is used to implement an operating power supply and a data communication line provided by the main module 1 to the display module 2.

As shown in fig. 2, the built-in three-phase current measurement circuit 101 includes an a-phase lead-in terminal, a B-phase lead-in terminal, a C-phase lead-in terminal, an a-phase lead-out terminal, a B-phase lead-out terminal, a C-phase lead-out terminal, an a-phase copper bar, a B-phase copper bar, a C-phase copper bar, an a-phase current transformer, a B-phase current transformer, and a C-phase current transformer; the phase A lead-in end, the phase B lead-in end and the phase C lead-in end are respectively an phase A loop lead-in end Ua_in, a phase B loop lead-in end Ub_in and a phase C loop lead-in end Uc_in, the phase A loop lead-in end Ua_in is connected with an A phase outlet end of the molded case circuit breaker, the phase B loop lead-in end Ub_in is connected with a phase B outlet end of the molded case circuit breaker, and the phase C loop lead-in end Uc_in is connected with a phase C outlet end of the molded case circuit breaker; the A-phase outlet wire end, the B-phase outlet wire end and the C-phase outlet wire end are respectively an A-phase loop outlet wire end Ua_out, a B-phase loop outlet wire end Ub_out and a C-phase loop outlet wire end Uc_out, wherein the A-phase loop outlet wire end Ua_out is connected with an A-phase inlet wire end of three-phase electric equipment, the B-phase loop outlet wire end Ub_out is connected with a B-phase inlet wire end of three-phase electric equipment, the C-phase loop outlet wire end Uc_out is connected with a C-phase inlet wire end of three-phase electric equipment, or the A-phase loop outlet wire end Ua_out is connected with an inlet wire end of a first single-phase electric equipment, the B-phase loop outlet wire end Ub_out is connected with an inlet wire end of a second single-phase electric equipment, and the C-phase loop outlet wire end Uc_out is connected with an inlet wire end of a third single-phase electric equipment; the A phase lead-in wire end, the B phase lead-in wire end, the C phase lead-in wire end, the A phase lead-out wire end, the B phase lead-out wire end and the C phase lead-out wire end are respectively connected through an A phase copper bar, a B phase copper bar and a C phase copper bar (the A phase copper bar Cu_A is connected with the A phase loop lead-in wire end Ua_in and the A phase loop lead-out wire end Ub_out, the B phase copper bar Cu_B is connected with the B phase loop lead-in wire end Ub_in and the B phase loop lead-out wire end Uc_out, the C phase copper bar Cu_C phase is connected with the C phase loop lead-in wire end Uc_in and the C phase loop lead-out wire end Uc_out), the widths of the A phase copper bar, the B phase copper bar and the C phase copper bar are consistent with the widths of the corresponding A phase copper bar, B phase copper bar and C phase copper bar on the molded case circuit breaker, and the C phase copper bar bear 630A respectively; the spacing between the A phase copper bar, the B phase copper bar and the C phase copper bar is identical to the spacing between the corresponding A phase copper bar, the B phase copper bar and the C phase copper bar on the molded case circuit breaker, the A phase copper bar Cu_A passes through the square inner hole of the A phase current transformer CT_A, when the A phase copper bar Cu_A has a large current to flow, the secondary side of the A phase current transformer CT_A outputs a milliamp current signal, the B phase copper bar Cu_B passes through the square inner hole of the B phase current transformer CT_B, when the B phase copper bar Cu_B has a large current to flow, the secondary side of the B phase current transformer CT_B outputs a milliamp current signal, the C phase copper bar Cu_C passes through the square inner hole of the C phase current transformer CT_C, and when the C phase copper bar Cu_C has a large current to flow, the secondary side of the C phase current transformer CT_C outputs a milliamp current signal; the secondary side output ends of the phase A current transformer CT_ A, B phase current transformers CT_B and C phase current transformer CT_C are connected with the SOC metering circuit 102.

As shown in fig. 2, the SOC metering circuit 102 includes: the secondary side output mA signal of the phase A current transformer CT_A outputs a sampling differential mV signal after passing through a differential sampling circuit formed by a sampling resistor fourth resistor R4 and a sampling resistor sixth resistor R6, the secondary side positive output end IA of the phase A current transformer CT_A is connected with one end of the sampling resistor fourth resistor R4, the secondary side negative output end IA of the phase A current transformer CT_A is connected with one end of the sampling resistor sixth resistor R6, the other end of the sampling resistor fourth resistor R4 and the other end of the sampling resistor sixth resistor R6 are connected with a signal ground GND, the secondary side positive output end IA of the phase A current transformer CT_A is connected with one end of a second resistor R2, the other end of the second resistor R2 is connected with one end of a fourth capacitor C4, the other end of the fourth capacitor C4 is connected with a signal ground GND, the second resistor R2 and the fourth capacitor C4 form an RC filter circuit, the positive output end IA of the secondary side of the A-phase current transformer CT_A is connected with the UP pin (positive analog input pin, pin 6) of the SOC metering chip U1 after passing through the RC filter circuit, the negative output end IA of the secondary side of the A-phase current transformer CT_A is connected with one end of an eighth resistor R8, the other end of the eighth resistor R8 is connected with one end of a seventh capacitor C7, the other end of the seventh capacitor C7 is connected with a signal ground GND, the eighth resistor R8 and the seventh capacitor C7 form an RC filter circuit, the negative output end IA of the secondary side of the A-phase current transformer CT_A is connected with the UN pin (negative analog input pin, pin 7) of the SOC metering chip U1 after passing through the RC filter circuit, and the UP pin and the UN pin of the SOC metering chip U1 form differential analog input to collect sampling differential mV signals corresponding to the secondary side of the A-phase current transformer CT_A, and the A-phase current is calculated.

The secondary side output mA signal of the B-phase current transformer CT_B outputs a sampling differential mV signal after passing through a differential sampling circuit formed by a sampling resistor eleventh resistor R11 and a sampling resistor thirteenth resistor R13, the secondary side positive output end IB of the B-phase current transformer CT_B is connected with one end of the sampling resistor eleventh resistor R11, the secondary side negative output end IB of the B-phase current transformer CT_B is connected with one end of the sampling resistor thirteenth resistor R13 after passing through the RC filter circuit, the other end of the sampling resistor eleventh resistor R11 and the other end of the sampling resistor thirteenth resistor R13 are connected with signal ground GND, the other end of the B-phase current transformer CT_B is connected with one end of a ninth resistor R9, the other end of the ninth resistor R9 is connected with one end of an eleventh capacitor C11, the other end of the eleventh capacitor C11 is connected with signal ground GND, the ninth resistor R9 and the eleventh capacitor C11 form a filter circuit, the secondary side positive output end IB of the B-phase current transformer CT_B is connected with an IBP pin (an analog pin P pin of a SOC chip U1) after passing through the RC filter circuit, the other end IB of the sampling resistor CT_B is connected with the second end of the second capacitor C14, the twelve end of the second capacitor C14 is connected with the other end of the RC filter circuit, the twelve end of the input end of the capacitor C12 is connected with the twelve end of the filter circuit is connected with the signal ground GND, and the IBP pin and the IBN pin of the SOC metering chip U1 form a differential analog input to acquire a sampling differential mV signal corresponding to the CT_B secondary side of the B-phase current transformer and calculate the B-phase current.

The secondary side output mA signal of the C-phase current transformer CT_C outputs a sampling differential mV signal after passing through a differential sampling circuit formed by a seventeenth resistor R17 and a nineteenth resistor R19 of the sampling resistor, a secondary side positive output end IC of the C-phase current transformer CT_C is connected with one end of the seventeenth resistor R17 of the sampling resistor, a secondary side negative output end IC of the C-phase current transformer CT_C is connected with one end of the nineteenth resistor R19 of the sampling resistor, the other end of the seventeenth resistor R17 of the sampling resistor and the other end of the nineteenth resistor R19 of the sampling resistor are connected with a signal ground GND, the other end of the C-phase current transformer CT_C 16 is connected with one end of the seventeenth capacitor C17, the other end of the seventeenth capacitor C17 is connected with a signal ground GND, the sixteenth resistor R16 and the seventeenth capacitor C17 of the second side positive output end IC of the C-phase current transformer CT_C form a filter circuit, the secondary side positive output end IC of the C-phase current transformer is connected with one end of an analog pin P pin of an SOC metering chip U1 (the analog pin P of the chip U1 is connected with the second end of the analog pin C21 of the C-phase current transformer C, the twenty-phase current transformer C21 is connected with the twenty-second end of the analog pin C21) of the second end of the C-phase current transformer C, the twenty-phase current transformer C21 is connected with the twenty-negative end of the twenty-phase current transformer C21 is connected with the twenty-phase end of the twenty-phase capacitor C1, and the IAP pin and the IAN pin of the SOC metering chip U1 form differential analog input to collect a differential mV signal from the secondary side of the C-phase current transformer CT_C and calculate the current of the C phase.

The fifth capacitor C5 and the eighth capacitor C8 form a parallel capacitor circuit, one end of the fifth capacitor C5 is connected with an LDO33 pin (pin 1) of the SOC metering chip U1, and the other end of the fifth capacitor C5 is connected with the signal ground GND; the sixteenth capacitor C16 and the twentieth capacitor C20 form a parallel capacitor circuit, one end of the sixteenth capacitor C16 is connected with the REFV pin (pin 13) of the SOC metering chip U1, and the other end of the sixteenth capacitor C16 is connected with the signal ground GND; the twenty-third capacitor C23 and the twenty-sixth capacitor C26 form a parallel capacitor circuit, one end of the twenty-third capacitor C23 is connected with an LDO18 pin (pin 19) of the SOC metering chip U1, and the other end of the twenty-third capacitor C23 is connected with the signal ground GND.

The DC-DC voltage reducing circuit provides +5V direct current working power supply and +3.3V direct current working power supply of the SOC metering chip U1 for the alarm circuit and the non-isolated RS485 circuit, and comprises: the voltage-reducing chip U3 converts DC12V direct current working power supply output by the switching power supply circuit 105 into +5V direct current working power supply, the VIN pin (pin 5) of the voltage-reducing chip U3 is connected with DC12V output by the switching power supply circuit 105 through a thirty-second filter capacitor C32, a thirty-first resistor R31 and a thirty-second resistor R32 form a serial voltage-dividing circuit to control the working enabling of the voltage-reducing chip U3, one end of the thirty-first resistor R31 is connected with the DC12V input working power supply, the EN pin (pin 4) of the voltage-reducing chip U3 is connected between the other end of the thirty-first resistor R31 and one end of the thirty-second resistor R32, the other end of the thirty-second resistor R32 is connected with a signal ground GND, the SW pin (pin 6) of the voltage-reducing chip U3 is connected with the cathode of a second diode D2, one end of a thirty-third capacitor C33 and one end of an inductor L1, the anode of the second diode D2 is connected with the signal ground GND, the other end of the thirty-third capacitor C33 is connected with the BST pin (pin 1) of the buck chip U3, the GND pin (pin 2) of the buck chip U3 is connected with the signal ground GND, a feedback circuit is formed by a thirty-fourth resistor R34, a thirty-fifth resistor R35, a thirty-seventh resistor R37 and a twenty-eighth capacitor C28, so that the buck chip U3 outputs +5V direct current working power supply, one ends of the thirty-fifth resistor R35, the thirty-seventh resistor R37 and the twenty-eighth capacitor C28 are connected with the FB pin (pin 3) of the buck chip U3, the other end of the thirty-seventh resistor R37 is connected with the signal ground GND, the other end of the thirty-fifth resistor R35 is connected with one end of the thirty-fourth resistor R34, the other end of the twenty-eighth capacitor C28 is connected with the other end of the thirty-fourth resistor R34 and the other end of the inductor L1 through a thirty-eighth filter capacitor C38 together to form a +5V direct current working power supply; the thirty-fourth capacitor C34 and the thirty-fifth capacitor C35 form a parallel filter circuit, the +5v direct current working power supply is connected with the IN pin and NC pin (pin 1 and pin 3) of the low dropout linear regulator U4 through one end of the thirty-fourth capacitor C34 and one end of the thirty-fifth capacitor C35, the other end of the thirty-fourth capacitor C34 and the other end of the thirty-fifth capacitor C35 are connected with the signal ground GND, the OUT pin (pin 5) of the low dropout linear regulator U4 outputs +3.3v direct current working power supply, the thirty-sixth capacitor C36 and the thirty-seventh capacitor C37 form a parallel filter circuit, the +3.3v direct current working power supply outputs stable +3.3v direct current working power supply through one end of the thirty-sixth capacitor C36 and one end of the thirty-seventh capacitor C37, the other end of the thirty-sixth capacitor C36 and the thirty-seventh capacitor C37 are connected with the signal ground GND, the GND pin (pin 2) of the low dropout linear regulator U4 is connected with the other end of the signal ground GND, and one end of the thirty-seventh capacitor C30 is connected with the other end of the thirty-fourth capacitor C4 (pin 4).

The SOC metering circuit 102 further includes 2 rotary encoding switches SW1 and SW2, when the rotary encoding switches SW1 and SW2 are both rotated to the 0 position, an external communication address of the isolation RS485 circuit 104 is set by the display module 2, and when any one of the rotary encoding switches SW1 and SW2 is rotated to the non-0 position, the external communication address of the isolation RS485 circuit 104 is set by the combination of the rotary encoding switches SW1 and SW 2; pin 1 of the rotary coding switch SW1 is connected with the SEG20 pin (pin 32) of the SOC metering chip U1 through an RC circuit formed by the first resistor R1 and the third capacitor C3, the SEG20 pin of the SOC metering chip U1 is connected with +3.3v through a pull-up resistor R30, pin 2 of the rotary coding switch SW1 is connected with the SEG21 pin (pin 31) of the SOC metering chip U1 through an RC circuit formed by the fifth resistor R5 and the sixth capacitor C6, the SEG21 pin of the SOC metering chip U1 is connected with +3.3v through a pull-up resistor R29, pin 4 of the rotary coding switch SW1 is connected with the SEG22 pin (pin 30) of the SOC metering chip U1 through an RC circuit formed by the seventh resistor R7 and the ninth capacitor C9, the SEG22 pin of the SOC metering chip U1 is connected with +3.3v through a pull-up resistor R28, the pin 8 of the rotary coding switch SW1 is connected with the SEG23 pin (pin 29) of the SOC metering chip U1 through a tenth resistor R10 and a tenth capacitor C10, and the SEG23 pin of the SOC metering chip U1 is connected with the ground signal GND through the pull-up resistor C3; pin 1 of rotary coding switch SW2 is connected to SEG24 pin (pin 28) of SOC measurement chip U1 through an RC circuit composed of twelfth resistor R12 and thirteenth capacitor C13, SEG24 pin of SOC measurement chip U1 is connected to +3.3v through pull-up resistor R26, pin 2 of rotary coding switch SW2 is connected to SEG25 pin (pin 27) of SOC measurement chip U1 through an RC circuit composed of fifteenth resistor R15 and fourteenth capacitor C14, SEG25 pin of SOC measurement chip U1 is connected to +3.3v through pull-up resistor R25, pin 4 of rotary coding switch SW2 is connected to SEG26 pin (pin 26) of SOC measurement chip U1 through an RC circuit composed of eighteenth resistor R18 and nineteenth capacitor C19, SEG26 pin of SOC measurement chip U1 is connected to +3.3v through pull-up resistor R24, pin 8 of rotary coding switch SW2 is connected to SEG27 pin (pin 25) of SOC measurement chip U1 through an RC circuit composed of twenty-fourth resistor R20 and twenty-fourth capacitor C24, and pin 4 of SOC measurement chip U1 is connected to +3.3v through pull-up resistor R23.

The SOC metering circuit 102 further includes that pin 3 of the reset chip U2 is connected to the +3.3v working power supply through one end of the twenty-ninth capacitor C29, the other end of the twenty-ninth capacitor C29 is connected to the signal ground GND, pin 2 of the reset chip U2 is connected to the signal ground GND through the pull-down resistor R36, an RC filter circuit is formed by the thirty-third resistor R33 and the thirty-fourth capacitor C34, one end of the thirty-third resistor R33 is connected to pin 2 of the reset chip U2, and the other end of the thirty-third resistor R33 is connected to the RSTN pin (pin 15) of the SOC metering chip U1.

The third resistor R3 is connected in parallel to both ends of the crystal oscillator X1, one end of the crystal oscillator X1 is connected with the HOSCO pin (pin 49) of the SOC measurement chip U1, the other end of the crystal oscillator X1 is connected with the HOSCI pin (pin 48) of the SOC measurement chip U1, the HOSCO pin of the SOC measurement chip U1 is connected with one end of the load capacitor C1, the HOSCI pin of the SOC measurement chip U1 is connected with one end of the load capacitor C2, and the other end of the load capacitor C1 and the other end of the load capacitor C2 are connected with the signal ground GND.

The SOC measurement chip circuit 102 controls the data receiving and transmitting function of the non-isolated RS485 circuit to perform data communication with the display module 2 through the serial port of the SOC measurement chip U1, and the non-isolated RS485 circuit includes: the DI pin (pin 4) of the RS485 transceiving control chip U8 is connected with the TX1 pin (serial port transmitting data pin 47) of the SOC metering chip U1, the DI pin (pin 4) of the RS485 transceiving control chip U8 is pulled up to a +5V working power supply through a fortieth resistor R40, the RO pin (pin 1) of the RS485 transceiving control chip U8 is connected with the RX1 pin (serial port receiving data pin 46) of the SOC metering chip U1, and the RS485 chip

-R E pin and DE pin (pin 2 and pin 3) of the transceiver control chip U8 are connected with TX0 pin (I/O pin 45) of the SOC metering chip U1, VDD pin (pin 8) of the RS485 transceiver control chip U8 is connected with +5v working power supply through one end of the thirty-ninth filter capacitor C39, the other end of the thirty-ninth filter capacitor C39 is linked with signal ground GND, GND pin (pin 5) of the RS485 transceiver control chip U8 is connected with +5v working power supply through pull-up resistor R46, a pin (pin 6) of the RS485 transceiver control chip U8 is connected with A1 end of the non-isolated RS485 circuit B provided for the display module 2 through magnetic bead FB1, B pin (pin 7) of the RS485 transceiver control chip U8 is connected with signal ground GND through pull-down resistor R42, B1 end of the non-isolated RS485 circuit B is provided for the display module 2 through magnetic bead FB2, A1 end and B1 end of the RS485 transceiver control chip U8 are provided with protection circuits, two ends of the protection circuits TVS tube 1 are respectively connected with A1 end and B1 end of the switch interface, and A1 end of the switch interface is respectively connected with signal ground GND1 end and a 2 interface, and power supply interface 2 is respectively connected with power supply end of the switch interface 2, and power supply interface 2 is connected with power supply end of the interface 12.

As shown in fig. 4, the SOC measurement chip circuit 102 communicates with a remote monitoring system through a serial port of the SOC measurement chip U1 to control a data transceiver function of the isolation RS485 circuit 104, and a communication address of the isolation RS485 circuit 104 may be set through a coding switch of the main module 1 or may be set through the display module 2; the isolation RS485 circuit 104 comprises a digital isolator U7 and an RS485 receiving and transmitting control chip U6, a VDD1 pin (pin 1) of the digital isolator U7 is connected with a +3.3V direct current working power supply through one end of a forty-first filter capacitor C41, the other end of the forty-first filter capacitor C41 and two GND1 pins (pin 2 and pin 8) of the digital isolator U7 are connected with a signal ground GND, an INB pin (pin 4) of the digital isolator U7 is connected with an AIN2 pin (I/O pin 4 and a network mark RE 2) of the SOC metering chip U1, the INB pin of the digital isolator U7 is pulled up to the +3.3V working power supply through a fifty-second resistor R52, the isolation RS485 circuit 104 works in a data sending state when the AIN2 pin of the SOC metering chip U1 outputs a low level, the isolation RS485 circuit 104 works in a data receiving state when the AIN2 pin of the SOC metering chip U1 outputs a high level, the INC pin (pin 5) of the digital isolator U7 is connected with the AIN1 pin (serial port transmitting data pin 3, network reference number TX 2) of the SOC metering chip U1, the INC pin (pin 5) of the digital isolator U7 is pulled up to +3.3V working power supply through a fifty-first resistor R51, the OUTD pin (pin 6) of the digital isolator U7 is connected with the AIN0 pin (serial port receiving data pin 2, network reference number RX 2) of the SOC metering chip U1, the OUTD pin of the digital isolator U7 is pulled up to +3.3V working power supply through a fifty-first resistor R50, the VDD2 (pin 16) of the digital isolator U7 is connected with DC5V working power supply through one end of a forty-second filter capacitor C42, the other end of the forty-second filter capacitor C42 and two GND2 pins (pin 15 and pin 9) of the digital isolator U7 are connected with signal ground G485 of the isolation RS485 circuit 104, the OUTB pin (pin 13) of the digital isolator U7 is connected with the base electrode of the NPN triode Q2 through a fifty-fifth resistor R55, the emitter electrode of the NPN triode Q2 is connected with the signal ground G485 of the isolation RS485 circuit 104, the OUTC pin (pin 12) of the digital isolator U7 is connected with the DI pin (pin 4) of the RS485 transceiving control chip U6 and is connected with a DC5V working power supply through a pull-up resistor R48, and the IND pin (pin 11) of the digital isolator U7 is connected with the RO pin (pin 1) of the RS485 transceiving control chip U6 and is connected with the signal ground G485 through a pull-up resistor R47

-a DC5V working power supply, the R E pin and the DE pin (pin 2 and pin 3) of the RS485 transceiving control chip U6 are connected with the collector of the NPN triode Q2 and are connected with the DC5V working power supply through the pull-up resistor R49, the VDD pin (pin 8) of the RS485 transceiving control chip U6 is connected with the DC5V working power supply through one end of the forty filter capacitor C40, the other end of the forty filter capacitor C40 and the GND pin (pin 5) of the RS485 transceiving control chip U6 are connected with the signal ground G485 of the isolation RS485 circuit 104, the a pin (pin 6) of the RS485 transceiving control chip U6 is connected with the DC5V working power supply through the pull-up resistor R54 and is externally provided with the signal ground G485 of the isolation RS485 circuit 104 through the pull-down resistor R53, the A2 end and the B2 end of the isolation RS485 circuit 104 are externally provided with the protection circuit through the magnetic bead R4, the A2 end and the protection circuit are respectively connected with the signal ground protection pin 2 of the two ends VD2, VD2 and the VD3 end of the protection circuit are connected with the signal ground protection circuit 2 of the isolation RS485 circuit 104, and the VD2 end of the protection circuit is connected with the signal ground protection circuit 2B 2 VD 3.

As shown in fig. 3, the SOC measurement chip U1 controls on/off of the output of the alarm circuit 103, and the alarm circuit 103 includes: the base of the NPN triode Q1 is connected with an RTCOUT pin (pin 61, network number MCU_DO 1) of the SOC metering chip U1 through a thirty eighth resistor R38, the emitter of the NPN triode Q1 is connected with a signal ground GND, the collector of the NPN triode Q1 is connected with one end of a control coil of a signal relay K1 serving as a switching device, the other end of the control coil of the signal relay K1 is connected with a +5V working power supply, two ends of the control coil of the signal relay K1 are connected with a diode D1 in parallel, the cathode of the diode D1 is connected with a +5V working power supply, the anode of the diode D1 is connected with the collector of the NPN triode Q1, the output port of the signal relay K1 is provided with an overvoltage protection circuit piezoresistor RV1, two ends of the piezoresistor RV1 are connected in parallel with the output port of the signal relay K1, when three-phase current parameters exceed the threshold range of the current parameters stored by the SOC metering chip U1, the RTCOUT pin (pin 61, the network number MCU_DO 1) of the signal relay U1 outputs a high level, the alarm circuit 103 outputs an audible and visual alarm signal output, the audible and visual alarm signal output, and the audible and visual alarm signal, and the alarm lamp 4 can be an indicator, a buzzer and the like.

As shown in fig. 5, the switching power supply circuit 105 provides a DC working power supply for the integrated three-phase current monitoring system, the switching power supply circuit 1052 outputs DC12V and DC5V, the DC12V power supply provides a 12V working power supply for the SOC metering circuit 102 and the display module 2, and the DC5V power supply provides a 5V working power supply for the isolation RS485 circuit 104; the input of the switching power supply circuit 105 can be powered from any single phase in the three-phase inlet wire end of the molded case circuit breaker, and can also be provided by an external control power supply, and the input range of the switching power supply circuit 105 supports AC 80-270V; the overvoltage and overcurrent protection circuit RV2 provides an input overvoltage and overcurrent protection function for the switching power supply circuit 105, the pin 1 of the overvoltage and overcurrent protection circuit RV2 is connected with one end of an alternating current power supply, the pin 3 of the overvoltage and overcurrent protection circuit RV2 is connected with the other end of the alternating current power supply, the pin 2 of the overvoltage and overcurrent protection circuit RV2 is connected with one end of the safety capacitor X2 and one end of the alternating current input of the rectifier bridge BR1, the other end of the alternating current input of the rectifier bridge BR1 is connected with the other end of the safety capacitor X2 and the pin 3 of the overvoltage and overcurrent protection circuit RV2, the fifty electrolytic capacitor C50, the inductor L2 and the fifty first electrolytic capacitor C51 form a pi-shaped filter circuit to filter the rectified voltage output by the rectifier bridge BR1 into stable direct current voltage, the positive end of the output voltage of the rectifier bridge BR1 is connected with the positive end of the fifty electrolytic capacitor C50 and one end of the inductor L2, the other end of the inductor L2 is connected with the positive end of a fifty-first electrolytic capacitor C51, the negative end of the fifty-first electrolytic capacitor C50 and the negative end of the fifty-first electrolytic capacitor C51 are connected with the negative end of the output voltage of the rectifier bridge BR1, the negative end of the fifty-first electrolytic capacitor C51 is connected with the signal ground PGND, the SW pin (pin 3) of the power control chip U9 is connected with the primary winding starting pin 5 of the transformer T1, the VDD pin (pin 2) of the power control chip U9 is connected with one end of a filter capacitor fifty-third capacitor C53, the other end of the fifty-third capacitor C53 is connected with the negative end of the fifty-first electrolytic capacitor C51 together with the 4 GND pins (pins 4, 5, 6 and 7) of the power control chip U9, the FB pin (pin 1) of the power control chip U9 is connected with the output pin 4 of the first isolation optocoupler N1, the output pin 3 of the first isolation optocoupler N1 is connected with the negative end of the fifty-first electrolytic capacitor C51, the unidirectional TVS tube D4 and the diode D5 are connected in series to form an absorption circuit, the damage of the power control chip U9 caused by the overhigh peak voltage of the SW pin (pin 3) of the power control chip U9 is prevented, the anode of the unidirectional TVS tube D4 is connected with the primary winding end pin 3 of the transformer T1 and the positive end of the fifty-first electrolytic capacitor C51, the cathode of the unidirectional TVS tube D4 is connected with the cathode of the diode D5, the anode of the diode D5 is connected with the primary winding start pin 5 of the transformer T1, the secondary output winding start pin 14 of the transformer T1 is connected with the anode of the diode D6, the cathode of the diode D6 is connected with the positive end of the forty-eighth electrolytic capacitor C48, the positive end direct current voltage of the forty-eighth electrolytic capacitor C48 outputs a stable DC12V working power supply after passing through an LC filter circuit formed by the inductor L3 and the fortieth-ninth electrolytic capacitor C49, one end of the inductor L3 is connected with the positive end of the fortieth-eighth electrolytic capacitor C48, the other end of the inductor L3 is connected with the positive end of a forty-ninth electrolytic capacitor C49, the secondary side output winding end pin 13 of the transformer T1 is connected with the negative end of a forty-eighth electrolytic capacitor C48 and the negative end of the forty-ninth electrolytic capacitor C49, the negative end of the forty-ninth electrolytic capacitor C49 is connected with a signal ground GND, the two ends of the input end pin 1 and the input end pin 2 of the first isolation optocoupler N1 are connected with a fifty-ninth resistor R59 in parallel, the input end pin 1 of the first isolation optocoupler N1 is connected with the positive end of the forty-eighth electrolytic capacitor C48 through a fifty-seventh resistor R57, the input end pin 2 of the first isolation optocoupler N1 is connected with the cathode (pin 2) of the reference chip U10, a sixty-first resistor R61 and the fifty-second capacitor C52 form a serial circuit, one end of the serial circuit is connected with the cathode (pin 2) of the reference chip U10, the other end of the serial circuit is connected with the reference end (pin 1) of the reference chip U10, the anode (pin 3) of the reference chip U10 is connected with the signal ground GND, one end of a sixty-third resistor R63 is connected with the signal ground GND, the other end of the sixty-third resistor R63 is connected with the reference end (pin 1) of the reference chip U10, one end of a sixty-second resistor R62 is connected with the positive end of a forty-ninth electrolytic capacitor C49, the other end of the sixty-second resistor R62 is connected with the reference end (pin 1) of the reference chip U10, and the signal ground GND is connected with PGND through a fifty-fourth safety capacitor C54; the DC5V working power supply is output by the switching power supply circuit 105 to provide a 5V working power supply for the isolation RS485 circuit 104, the anode of the diode D3 is connected with the secondary side output winding starting pin 8 of the transformer T1, a forty-four capacitor C44 and a forty-five capacitor C45 form a parallel circuit, one end of the parallel circuit is connected with the cathode of the diode D3 and the IN pin and NC pin (pin 1 and pin 3) of the RS485 transceiving control chip U8, the other end of the parallel circuit is connected with the secondary side output winding ending pin 9 of the transformer T1 and the signal ground G485 of the isolation RS485 circuit, the other NC pin (pin 4) of the RS485 transceiving control chip U8 is connected with one end of the forty-three capacitor C43, the other end of the forty-three capacitor C43 and the GND pin (pin 2) of the RS485 transceiving control chip U8 are connected with the signal ground G485 of the isolation RS485 circuit, and the OUT pin (pin 5) of the RS485 transceiving control chip U8 is filtered through the forty-six capacitor C46 to output the DC5V working power supply.

While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that these are by way of example only, and the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the principles and spirit of the invention, but such changes and modifications fall within the scope of the invention.

Claims

1. The integrated three-phase current monitoring system is characterized by comprising a main module, a display module, a connecting wire and an audible and visual alarm, wherein the incoming line end of the main module is connected with the outgoing line end of a molded case circuit breaker, the outgoing line end of the main module is connected with the power supply end of electric equipment, the main module is arranged right below the outgoing line end of the molded case circuit breaker in a low-voltage power distribution cabinet, the display module is arranged on the front panel of the low-voltage power distribution cabinet in an embedded mode, the display module is electrically connected with the main module through the connecting wire, and the main module is electrically connected with the audible and visual alarm;

2. The integrated three-phase current monitoring system of claim 1, wherein the built-in three-phase current measurement circuit comprises an a-phase lead-in terminal, a B-phase lead-in terminal, a C-phase lead-in terminal, an a-phase lead-out terminal, a B-phase lead-out terminal, a C-phase lead-out terminal, an a-phase copper bar, a B-phase copper bar, a C-phase copper bar, an a-phase current transformer, a B-phase current transformer, and a C-phase current transformer; the phase A lead-in end, the phase B lead-in end and the phase C lead-in end are respectively an phase A loop lead-in end Ua_in, a phase B loop lead-in end Ub_in and a phase C loop lead-in end Uc_in, the phase A loop lead-in end Ua_in is connected with an A phase outlet end of the molded case circuit breaker, the phase B loop lead-in end Ub_in is connected with a phase B outlet end of the molded case circuit breaker, and the phase C loop lead-in end Uc_in is connected with a phase C outlet end of the molded case circuit breaker; the A-phase outlet wire end, the B-phase outlet wire end and the C-phase outlet wire end are respectively an A-phase loop outlet wire end Ua_out, a B-phase loop outlet wire end Ub_out and a C-phase loop outlet wire end Uc_out, wherein the A-phase loop outlet wire end Ua_out is connected with an A-phase inlet wire end of three-phase electric equipment, the B-phase loop outlet wire end Ub_out is connected with a B-phase inlet wire end of three-phase electric equipment, the C-phase loop outlet wire end Uc_out is connected with a C-phase inlet wire end of three-phase electric equipment, or the A-phase loop outlet wire end Ua_out is connected with an inlet wire end of a first single-phase electric equipment, the B-phase loop outlet wire end Ub_out is connected with an inlet wire end of a second single-phase electric equipment, and the C-phase loop outlet wire end Uc_out is connected with an inlet wire end of a third single-phase electric equipment; the A phase wire inlet end, the B phase wire inlet end, the C phase wire inlet end, the A phase wire outlet end, the B phase wire outlet end and the C phase wire outlet end are respectively connected through an A phase copper bar, a B phase copper bar and a C phase copper bar, the widths of the A phase copper bar, the B phase copper bar and the C phase copper bar are consistent with the widths of the corresponding A phase copper bar, B phase copper bar and C phase copper bar on the molded case circuit breaker, and the maximum alternating current born by the A phase copper bar, the B phase copper bar and the C phase copper bar is 630A; the spacing between the A phase copper bar, the B phase copper bar and the C phase copper bar is identical to the spacing between the corresponding A phase copper bar, the B phase copper bar and the C phase copper bar on the molded case circuit breaker, the A phase copper bar Cu_A passes through the square inner hole of the A phase current transformer CT_A, when the A phase copper bar Cu_A has a large current to flow, the secondary side of the A phase current transformer CT_A outputs a milliamp current signal, the B phase copper bar Cu_B passes through the square inner hole of the B phase current transformer CT_B, when the B phase copper bar Cu_B has a large current to flow, the secondary side of the B phase current transformer CT_B outputs a milliamp current signal, the C phase copper bar Cu_C passes through the square inner hole of the C phase current transformer CT_C, and when the C phase copper bar Cu_C has a large current to flow, the secondary side of the C phase current transformer CT_C outputs a milliamp current signal; the secondary side output ends of the phase A current transformer CT_ A, B phase current transformers CT_B and C phase current transformers CT_C are connected with an SOC metering circuit.

3. The integrated three-phase current monitoring system of claim 2, wherein the SOC metering circuit comprises: the secondary side output mA signal of the phase A current transformer CT_A outputs a sampling differential mV signal after passing through a differential sampling circuit formed by a sampling resistor fourth resistor R4 and a sampling resistor sixth resistor R6, the secondary side positive output end IA of the phase A current transformer CT_A is connected with one end of the sampling resistor fourth resistor R4, the secondary side negative output end IA of the phase A current transformer CT_A is connected with one end of the sampling resistor sixth resistor R6, the other end of the sampling resistor fourth resistor R4 and the other end of the sampling resistor sixth resistor R6 are connected with signal ground GND, the secondary side positive output end IA of the phase A current transformer CT_A is connected with one end of a second resistor R2, the other end of the second resistor R2 is connected with one end of a fourth capacitor C4, the other end of the fourth capacitor C4 is connected with signal ground GND, the second resistor R2 and the fourth capacitor C4 form an RC filter circuit, the secondary side positive output end IA of the A-phase current transformer CT_A is connected with the UP pin of the SOC metering chip U1 after passing through the RC filter circuit, the secondary side negative output end IA of the A-phase current transformer CT_A is connected with one end of the eighth resistor R8, the other end of the eighth resistor R8 is connected with one end of the seventh capacitor C7, the other end of the seventh capacitor C7 is connected with the signal ground GND, the eighth resistor R8 and the seventh capacitor C7 form the RC filter circuit, the secondary side negative output end IA of the A-phase current transformer CT_A is connected with the UN pin of the SOC metering chip U1 after passing through the RC filter circuit, and the UP pin and the UN pin of the SOC metering chip U1 form differential analog input to collect sampling differential mV signals corresponding to the secondary side of the A-phase current transformer CT_A and calculate the A-phase current;

The secondary side output mA signal of the B-phase current transformer CT_B outputs a sampling differential mV signal after passing through a differential sampling circuit formed by a sampling resistor eleventh resistor R11 and a sampling resistor thirteenth resistor R13, the secondary side positive output end IB of the B-phase current transformer CT_B is connected with one end of the sampling resistor eleventh resistor R11, the secondary side negative output end IB of the B-phase current transformer CT_B is connected with one end of the sampling resistor thirteenth resistor R13, the other end of the sampling resistor eleventh resistor R11 and the other end of the sampling resistor thirteenth resistor R13 are connected with a signal ground GND, the secondary side positive output end IB of the B-phase current transformer CT_B is connected with one end of a ninth resistor R9, the other end of the ninth resistor R9 is connected with one end of an eleventh capacitor C11, the other end of the eleventh capacitor C11 is connected with a signal ground GND, the ninth resistor R9 and the eleventh capacitor C11 form an RC filter circuit, the secondary side positive output end IB of the B-phase current transformer CT_B is connected with the IBP pin of the SOC metering chip U1 after passing through the RC filter circuit, the secondary side negative output end IB of the B-phase current transformer CT_B for collecting differential mV signals is connected with one end of a fourteenth resistor R14, the other end of the fourteenth resistor R14 is connected with one end of a twelfth capacitor C12, the other end of the twelfth capacitor C12 is connected with a signal ground GND, the fourteenth resistor R14 and the twelfth capacitor C12 form an RC filter circuit, the secondary side negative output end IB of the B-phase current transformer CT_B is connected with the IBN pin of the SOC metering chip U1 after passing through the RC filter circuit, and the IBP pin and the IBN pin of the SOC metering chip U1 form differential analog input for collecting the sampling differential mV signals corresponding to the secondary side of the B-phase current transformer CT_B and calculating the current of the B-phase;

The secondary side output mA signal of the C-phase current transformer CT_C outputs a sampling differential mV signal after passing through a differential sampling circuit formed by a seventeenth resistor R17 and a nineteenth resistor R19 of the sampling resistor, a secondary side positive output end IC of the C-phase current transformer CT_C is connected with one end of the seventeenth resistor R17 of the sampling resistor, a secondary side negative output end IC of the C-phase current transformer CT_C is connected with one end of the nineteenth resistor R19 of the sampling resistor, the other end of the seventeenth resistor R17 and the other end of the nineteenth resistor R19 of the sampling resistor are connected with a signal ground GND, a secondary side positive output end IC of the C-phase current transformer CT_C is connected with one end of a sixteenth resistor R16, the other end of the sixteenth resistor R16 is connected with one end of the seventeenth capacitor C17, the other end of the seventeenth capacitor C17 is connected with a signal ground GND, the sixteenth resistor R16 and the seventeenth capacitor C17 form an RC filter circuit, a secondary side positive output end IC of the C-phase current transformer is connected with an IAP end pin of the SOC metering chip U1 after passing through the RC filter circuit, a secondary side negative output end IC of the C-phase current transformer CT_C is connected with one end of a twenty-first resistor R21, the other end of the twenty-first resistor R21 is connected with one end of a twenty-first capacitor C21, the other end of the twenty-first capacitor C21 is connected with a signal ground GND, the twenty-first resistor R21 and the twenty-first capacitor C21 form the RC filter circuit, the secondary side negative output end IC of the C-phase current transformer CT_C is connected with an IAN pin of the SOC metering chip U1 after passing through the RC filter circuit, and the IAP pin and the IAN pin of the SOC metering chip U1 form differential analog input to collect a secondary side sampling differential mV of the C-phase current transformer CT_C and calculate the C-phase current;

The fifth capacitor C5 and the eighth capacitor C8 form a parallel capacitor circuit, one end of the fifth capacitor C5 is connected with an LDO33 pin of the SOC metering chip U1, and the other end of the fifth capacitor C5 is connected with the signal ground GND; the sixteenth capacitor C16 and the twentieth capacitor C20 form a parallel capacitor circuit, one end of the sixteenth capacitor C16 is connected with the REFV pin of the SOC metering chip U1, and the other end of the sixteenth capacitor C16 is connected with the signal ground GND; a twenty-third capacitor C23 and a twenty-sixth capacitor C26 form a parallel capacitor circuit, one end of the twenty-third capacitor C23 is connected with an LDO18 pin of the SOC metering chip U1, and the other end of the twenty-third capacitor C23 is connected with a signal ground GND;

the DC-DC voltage reducing circuit provides +5V direct current working power supply and +3.3V direct current working power supply of the SOC metering chip U1 for the alarm circuit and the non-isolated RS485 circuit, and comprises: the buck chip U3 converts DC12V direct current working power supply output by the switching power supply circuit into +5V direct current working power supply, the VIN pin of the buck chip U3 is connected with DC12V output by the switching power supply circuit through a thirty-second filter capacitor C32, a thirty-first resistor R31 and a thirty-second resistor R32 form a serial voltage dividing circuit to control the working enabling of the buck chip U3, one end of the thirty-first resistor R31 is connected with the DC12V input working power supply, the EN pin of the buck chip U3 is connected between the other end of the thirty-first resistor R31 and one end of the thirty-second resistor R32, the other end of the thirty-second resistor R32 is connected with a signal ground GND, the SW pin of the buck chip U3 is connected with the cathode of a second diode D2, one end of the thirty-third capacitor C33 and one end of the inductor L1, the anode of the second diode D2 is connected with the signal ground GND, the other end of the thirty-third capacitor C33 is connected with a BST pin of the buck chip U3, the GND pin of the buck chip U3 is connected with a signal ground GND, a feedback circuit is formed by a thirty-fourth resistor R34, a thirty-fifth resistor R35, a thirty-seventh resistor R37 and a twenty-eighth capacitor C28, so that the buck chip U3 outputs a +5V direct current working power supply, one ends of the thirty-fifth resistor R35, the thirty-seventh resistor R37 and the twenty-eighth capacitor C28 are connected with the FB pin of the buck chip U3, the other end of the thirty-seventh resistor R37 is connected with the signal ground GND, the other end of the thirty-fifth resistor R35 is connected with one end of the thirty-fourth resistor R34, and the other end of the twenty-eighth capacitor C28, the thirty-fourth resistor R34 and the other end of the inductor L1 are connected with the +5V direct current working power supply together through a thirty-eighth filter capacitor C38; the thirty-fourth capacitor C34 and the thirty-fifth capacitor C35 form a parallel filter circuit, the +5V direct current working power supply is connected with an IN pin and an NC pin of the low-dropout linear voltage regulator U4 through one end of the thirty-fourth capacitor C34 and one end of the thirty-fifth capacitor C35, the other end of the thirty-fourth capacitor C34 and the other end of the thirty-fifth capacitor C35 are connected with a signal ground GND, the OUT pin of the low-dropout linear voltage regulator U4 outputs +3.3V direct current working power supply, the thirty-sixth capacitor C36 and the thirty-seventh capacitor C37 form a parallel filter circuit, the +3.3V direct current working power supply outputs stable +3.3V direct current working power supply through one end of the thirty-sixth capacitor C36 and one end of the thirty-seventh capacitor C37, the other end of the thirty-sixth capacitor C36 and the other end of the thirty-seventh capacitor C37 are connected with the signal ground GND, the GND pin of the low-dropout linear voltage regulator U4 is connected with the signal ground GND, one end of the thirty-fifth capacitor C30 is connected with the other NC pin of the low-dropout linear voltage regulator U4, and the other end of the thirty-seventh capacitor C30 is connected with the signal ground GND.

4. The integrated three-phase current monitoring system of claim 3, wherein the SOC metering circuit further comprises 2 rotary encoder switches SW1 and SW2, the external communication address of the isolated RS485 circuit is set by the display module when both rotary encoder switches SW1 and SW2 are rotated to the 0 position, and the external communication address of the isolated RS485 circuit is set by the combination of rotary encoder switches SW1 and SW2 when either of the rotary encoder switches SW1 and SW2 is rotated to the non-0 position; pin 1 of the rotary coding switch SW1 is connected with an SEG20 pin of the SOC metering chip U1 through an RC circuit formed by a first resistor R1 and a third capacitor C3, the SEG20 pin of the SOC metering chip U1 is connected with +3.3V through a pull-up resistor R30, pin 2 of the rotary coding switch SW1 is connected with an SEG21 pin of the SOC metering chip U1 through an RC circuit formed by a fifth resistor R5 and a sixth capacitor C6, the SEG21 pin of the SOC metering chip U1 is connected with +3.3V through a pull-up resistor R29, pin 4 of the rotary coding switch SW1 is connected with an SEG22 pin of the SOC metering chip U1 through an RC circuit formed by a seventh resistor R7 and a ninth capacitor C9, the SEG22 pin of the SOC metering chip U1 is connected with +3.3V through a pull-up resistor R28, pin 8 of the rotary coding switch SW1 is connected with an SEG23 pin of the SOC metering chip U1 through an RC circuit formed by a tenth resistor R10 and a tenth capacitor C10, and the SEG23 pin of the SOC metering chip U1 is connected with a ground signal GND 2 through a pull-up resistor R27 and a ninth capacitor C9; pin 1 of rotary coding switch SW2 is connected to SEG24 pin of SOC measurement chip U1 through an RC circuit composed of twelfth resistor R12 and thirteenth capacitor C13, SEG24 pin of SOC measurement chip U1 is connected to +3.3v through pull-up resistor R26, pin 2 of rotary coding switch SW2 is connected to SEG25 pin of SOC measurement chip U1 through an RC circuit composed of fifteenth resistor R15 and fourteenth capacitor C14, SEG25 pin of SOC measurement chip U1 is connected to +3.3v through pull-up resistor R25, pin 4 of rotary coding switch SW2 is connected to SEG26 pin of SOC measurement chip U1 through an RC circuit composed of eighteenth resistor R18 and nineteenth capacitor C19, SEG26 pin of SOC measurement chip U1 is connected to +3.3v through pull-up resistor R24, pin 8 of rotary coding switch SW2 is connected to SEG27 pin of SOC measurement chip U1 through an RC circuit composed of twenty-fourth resistor R20 and twenty-fourth capacitor C24, and SEG27 pin of SOC measurement chip U1 is connected to +3v through pull-up resistor R23 and is connected to ground signal GND 2.

5. The integrated three-phase current monitoring system according to claim 3, wherein the SOC metering circuit further comprises a pin 3 of the reset chip U2 connected to the +3.3v operating power supply through one end of a twenty-ninth capacitor C29, the other end of the twenty-ninth capacitor C29 is connected to the signal ground GND, the pin 2 of the reset chip U2 is connected to the signal ground GND through a pull-down resistor R36, an RC filter circuit is formed by a thirty-third resistor R33 and a thirty-fourth capacitor C34, one end of the thirty-third resistor R33 is connected to the pin 2 of the reset chip U2, and the other end of the thirty-third resistor R33 is connected to the RSTN pin of the SOC metering chip U1;

the two ends of the crystal oscillator X1 are connected with a third resistor R3 in parallel, one end of the crystal oscillator X1 is connected with a HOSCO pin of the SOC metering chip U1, the other end of the crystal oscillator X1 is connected with a HOSCI pin of the SOC metering chip U1, the HOSCO pin of the SOC metering chip U1 is connected with one end of the load capacitor C1, the HOSCI pin of the SOC metering chip U1 is connected with one end of the load capacitor C2, and the other end of the load capacitor C1 and the other end of the load capacitor C2 are connected with the signal ground GND.

6. The integrated three-phase current monitoring system of claim 3, wherein the SOC metering chip circuit is in data communication with the display module through a serial port of the SOC metering chip U1 controlling a data transceiver function of the non-isolated RS485 circuit, the non-isolated RS485 circuit comprising: DI pin of RS485 receiving and transmitting control chip U8 connects TX1 pin of SOC measurement chip U1, DI pin of RS485 receiving and transmitting control chip U8 pulls up to +5V operating power supply through fortieth resistance R40, RO pin of RS485 receiving and transmitting control chip U8 connects RX1 pin of SOC measurement chip U1, RS485 receiving and transmitting control chip-

The R E pin and the DE pin of U8 are connected with the TX0 pin of the SOC metering chip U1, the VDD pin of the RS485 transceiving control chip U8 is connected with a +5V working power supply through one end of a thirty-ninth filter capacitor C39, the other end of the thirty-ninth filter capacitor C39 is connected with a signal ground GND, the GND pin of the RS485 transceiving control chip U8 is connected with a +5V working power supply through a pull-up resistor R46, the A pin of the RS485 transceiving control chip U8 is connected with an A1 end of a non-isolated RS485 circuit B through a magnetic bead FB1, the B pin of the RS485 transceiving control chip U8 is connected with a signal ground GND through a pull-down resistor R42, the B1 end of the RS485 transceiving control chip U8 is connected with a B1 end of the non-isolated RS485 circuit B through a magnetic bead FB2, the A1 end and the B1 end of the RS485 transceiving control chip U8 are respectively connected with the A1 end and the B1 end, the A1 end and the B1 end of the protection circuit is respectively connected with a pin 5 of an RJ11 interface P1 and a pin 6, and the R11 interface P1 and the B1 end of the R11 interface P1 is respectively connected with the TV end of the TV power supply 12 and the display module to provide a communication function of the power supply.

7. The integrated three-phase current monitoring system according to claim 4, wherein the SOC metering chip circuit is used for controlling the data transceiving function of the isolated RS485 circuit to communicate with the remote monitoring system through the serial port of the SOC metering chip U1, and the communication address of the isolated RS485 circuit can be set through the coding switch of the main module or can be set through the display module; the isolation RS485 circuit comprises a digital isolator U7 and an RS485 receiving and transmitting control chip U6, a VDD1 pin of the digital isolator U7 is connected with a +3.3V direct current working power supply through one end of a forty-first filter capacitor C41, the other end of the forty-first filter capacitor C41 and two GND1 pins of the digital isolator U7 are connected with a signal ground GND, an INB pin of the digital isolator U7 is connected with an AIN2 pin of the SOC metering chip U1, the INB pin of the digital isolator U7 is pulled up to the +3.3V working power supply through a fifty-second resistor R52, when the AIN2 pin of the SOC metering chip U1 outputs a low level, the isolation RS485 circuit works in a transmitting data state, when the AIN2 pin of the SOC metering chip U1 outputs a high level, the isolation RS485 circuit works in a receiving data state, the INC pin of the digital isolator U7 is connected with the AIN1 pin of the SOC metering chip U1, the INC pin of the digital isolator U7 is pulled up to the +3.3V working power supply through a fifty-first resistor R51, the OUTD pin of the digital isolator U7 is connected with the AIN0 pin of the SOC metering chip U1, the OUTD pin of the digital isolator U7 is pulled up to +3.3V working power supply through a fifty-th resistor R50, the VDD2 of the digital isolator U7 is connected with the DC5V working power supply through one end of a forty-second filter capacitor C42, the other end of the forty-second filter capacitor C42 and two GND2 pins of the digital isolator U7 are connected with the signal ground G485 of an isolated RS485 circuit, the OUTB pin of the digital isolator U7 is connected with the base electrode of an NPN triode Q2 through a fifty-fifth resistor R55, the emitter electrode of the NPN triode Q2 is connected with the signal ground G485 of the isolated RS485 circuit, the TC pin of the digital isolator U7 is connected with the DI pin of the RS485 transceiving control chip U6 and is connected with the DC5V working power supply through a pull-up resistor R48, the IND pin of the digital isolator U7 is connected with the RO pin of the RS485 transceiving control chip U6 and is connected with the DC5V working power supply through a pull-up resistor R47, RS 485-, a-, and a combination of

The R E pin and the DE pin of the transceiving control chip U6 are connected with the collector of the NPN triode Q2 and are connected with a DC5V working power supply through a pull-up resistor R49, the VDD pin of the RS485 transceiving control chip U6 is connected with the DC5V working power supply through one end of a forty filter capacitor C40, the other end of the forty filter capacitor C40 and the GND pin of the RS485 transceiving control chip U6 are connected with a signal ground G485 of an isolated RS485 circuit, the A pin of the RS485 transceiving control chip U6 is connected with the DC5V working power supply through a pull-up resistor R54 and is externally provided with an A2 end of the isolated RS485 circuit through a magnetic bead FB3, the B2 end and the B2 end of the isolated RS485 circuit are externally provided with a protection circuit through a magnetic bead FB4, the two ends of the TVS tube VD2 of the protection circuit are respectively connected with the A2 end and the B2 end, the 1 of the protection circuit VD3 is connected with the A2 end, the pin 2 end of the protection circuit VD3 is connected with the B2 end of the protection circuit, and the B3 end of the protection circuit is connected with the signal ground G485 of the RS485 circuit through the RS 3.

8. The integrated three-phase current monitoring system according to claim 4, wherein the SOC meter chip U1 controls on-off of an output of an alarm circuit, the alarm circuit comprising: the base of the NPN triode Q1 is connected with an RTCOUT pin of the SOC metering chip U1 through a thirty eighth resistor R38, the emitter of the NPN triode Q1 is connected with a signal ground GND, the collector of the NPN triode Q1 is connected with one end of a control coil of a signal relay K1 serving as a switching device, the other end of the control coil of the signal relay K1 is connected with a +5V working power supply, two ends of the control coil of the signal relay K1 are connected with a diode D1 in parallel, the cathode of the diode D1 is connected with a +5V working power supply, the anode of the diode D1 is connected with the collector of the NPN triode Q1, the output port of the signal relay K1 is provided with an overvoltage protection circuit piezoresistor RV1, two ends of the piezoresistor RV1 are connected with the output port of the signal relay K1 in parallel, when three-phase current parameters exceed the current parameter threshold range stored by the SOC metering chip U1, the RTCOUT pin of the SOC metering chip U1 outputs a high level, and the alarm circuit outputs a conduction sound and light alarm signal.

9. The integrated three-phase current monitoring system of claim 3, wherein the switching power supply circuit provides a direct current working power supply for the integrated three-phase current monitoring system, the switching power supply circuit outputs a DC12V power supply and a DC5V power supply by 2 paths of direct current power supplies, the DC12V power supply provides a 12V working power supply for the SOC metering circuit and the display module, and the DC5V power supply provides a 5V working power supply for the isolation RS485 circuit; the input of the switching power supply circuit can be powered from any single phase in the three-phase inlet wire end of the molded case circuit breaker, and can also be provided by an external control power supply, and the input range of the switching power supply circuit supports AC 80-270V; the overvoltage and overcurrent protection circuit RV2 provides an input overvoltage and overcurrent protection function for the switching power supply circuit, a pin 1 of the overvoltage and overcurrent protection circuit RV2 is connected with one end of an alternating current power supply, a pin 3 of the overvoltage and overcurrent protection circuit RV2 is connected with the other end of the alternating current power supply, a pin 2 of the overvoltage and overcurrent protection circuit RV2 is connected with one end of a safety capacitor X2 and an alternating current input end of a rectifier bridge BR1, the other end of the alternating current input end of the rectifier bridge BR1 is connected with the other end of the safety capacitor X2 and the pin 3 of the overvoltage and overcurrent protection circuit RV2, a pi-type filter circuit consisting of a fifty electrolytic capacitor C50, an inductor L2 and a fifty-first electrolytic capacitor C51 filters rectified voltage output by the rectifier bridge BR1 into stable direct current voltage, the positive end of the output voltage of the rectifier bridge BR1 is connected with the positive end of the fifty electrolytic capacitor C50 and one end of the inductor L2, the other end of the inductor L2 is connected with the positive end of the fifty-first electrolytic capacitor C51, the negative terminal of the fifty electrolytic capacitor C50 and the negative terminal of the fifty first electrolytic capacitor C51 are connected with the output voltage negative terminal of the rectifier bridge BR1, the negative terminal of the fifty first electrolytic capacitor C51 is connected with the signal ground PGND, the SW pin of the power control chip U9 is connected with the primary winding starting pin 5 of the transformer T1, the VDD pin of the power control chip U9 is connected with one end of the fifty third capacitor C53 of the filter capacitor, the other end of the fifty third capacitor C53 and the 4 GND pins of the power control chip U9 are connected with the negative terminal of the fifty first electrolytic capacitor C51 together, the FB pin of the power control chip U9 is connected with the output pin 4 of the first isolation optocoupler N1, the output pin 3 of the first isolation optocoupler N1 is connected with the negative terminal of the fifty first electrolytic capacitor C51, the unidirectional TVS tube D4 and the diode D5 are connected in series to form an absorption circuit, so that the SW pin peak voltage of the power control chip U9 is prevented from being excessively high and damaging the power control chip U9, the anode of the unidirectional TVS tube D4 is connected with the primary winding end pin 3 of the transformer T1 and the positive end of the fifty-first electrolytic capacitor C51, the cathode of the unidirectional TVS tube D4 is connected with the cathode of the diode D5, the anode of the diode D5 is connected with the primary winding start pin 5 of the transformer T1, the secondary output winding start pin 14 of the transformer T1 is connected with the anode of the diode D6, the cathode of the diode D6 is connected with the positive end of the forty-eighth electrolytic capacitor C48, the positive end direct current voltage of the forty-eighth electrolytic capacitor C48 outputs a stable DC12V working power supply after passing through an LC filter circuit formed by the inductor L3 and the forty-ninth electrolytic capacitor C49, one end of the inductor L3 is connected with the positive end of the forty-eighth electrolytic capacitor C48, the other end of the inductor L3 is connected with the positive end of the forty-ninth electrolytic capacitor C49, the secondary output winding end pin 13 of the transformer T1 is connected with the negative end of the forty-eighth electrolytic capacitor C48 and the negative end of the forty-ninth electrolytic capacitor C49, the negative end of the forty-ninth electrolytic capacitor C49 is connected with the signal ground GND, the two ends of the input end pin 1 and the input end pin 2 of the first isolation optocoupler N1 are connected with a fifty-ninth resistor R59 in parallel, the input end pin 1 of the first isolation optocoupler N1 is connected with the positive end of the forty-eighth electrolytic capacitor C48 through a fifty-seventh resistor R57, the input end pin 2 of the first isolation optocoupler N1 is connected with the cathode of the reference chip U10, the sixty-first resistor R61 and the fifty-second capacitor C52 form a serial circuit, one end of the serial circuit is connected with the cathode of the reference chip U10, the other end of the serial circuit is connected with the reference end of the reference chip U10, the anode of the reference chip U10 is connected with the signal ground GND, one end of the sixty-third resistor R63 is connected with the signal ground GND, the other end of the sixty-third resistor R63 is connected with the reference end of the reference chip U10, one end of the sixty-second resistor R62 is connected with the positive end of the forty-ninth electrolytic capacitor C49, the other end of the sixty-second resistor R62 is connected with the reference end of the reference chip U10, and the signal ground GND is connected with PGND through a fifty-fourth safety capacitor C54; the DC5V working power supply is output by the switching power supply circuit to provide a 5V working power supply for the isolation RS485 circuit, the anode of the diode D3 is connected with the secondary side output winding starting pin 8 of the transformer T1, a forty-four capacitor C44 and a forty-five capacitor C45 form a parallel circuit, one end of the parallel circuit is connected with the cathode of the diode D3 and the IN pin and NC pin of the RS485 transceiving control chip U8, the other end of the parallel circuit is connected with the secondary side output winding ending pin 9 of the transformer T1 and the signal ground G485 of the isolation RS485 circuit, the other NC pin of the RS485 transceiving control chip U8 is connected with one end of the forty-three capacitor C43, the other end of the forty-three capacitor C43 and the GND pin of the RS485 transceiving control chip U8 are connected with the signal ground G485 of the isolation RS485 circuit, and the OUT pin of the RS485 transceiving control chip U8 outputs the DC5V working power supply through filtering of the forty-six capacitor C46.

10. The integrated three-phase current monitoring system of claim 3, wherein the display module is provided with a DC12V power supply output by the main module, the display module is in data communication with the main module through a connecting wire and a non-isolated RS485 circuit in the main module, the connecting wire is a 6-core RJ11 connecting wire, an MCU in a display circuit on the display module controls a data receiving and transmitting function of the non-isolated RS485 circuit through a serial port, and the MCU controls a display driving chip in the display circuit to display three-phase current data in situ, wherein the display circuit comprises LED display and LCD display.