CN218383047U

CN218383047U - Plug-in relay single-phase thing allies oneself with table based on zero magnetic flux active current sampling

Info

Publication number: CN218383047U
Application number: CN202222578484.0U
Authority: CN
Inventors: 双俊锋; 林新正; 后东超
Original assignee: Hangzhou Vango Technologies Inc
Current assignee: Hangzhou Vango Technologies Inc
Priority date: 2022-09-28
Filing date: 2022-09-28
Publication date: 2023-01-24
Anticipated expiration: 2032-09-28

Abstract

The utility model discloses a single-phase thing of plug-in relay allies oneself with table based on zero magnetic flux active current sampling, include: a plug-in relay and a zero-flux current sensor; the zero-flux current sensor consists of a zero-flux transformer coil assembly, a signal conditioning circuit and a current sampling circuit; the signal conditioning circuit is matched with a zero-flux transformer coil assembly to realize zero-flux current sampling; in the signal conditioning circuit, zero magnetic flux active sampling is adopted. The zero magnetic flux current sampling technology and the pluggable relay combination are applied to the IOT, so that the problem that the relay cannot be replaced during field operation is solved, the problem of heating during manganin sampling is solved, the metering precision is improved, and the metering scheme is an ideal metering scheme for the single-phase IOT complete machine of the pluggable relay.

Description

Plug-in relay single-phase thing allies oneself with table based on zero magnetic flux active current sampling

Technical Field

The utility model relates to a single-phase thing allies oneself with table, especially a single-phase thing of plug-in relay allies oneself with table based on zero magnetic flux active current sampling.

Background

At present, the national power grid has two single-phase intelligent phenotypes with different technical route schemes, one is a single-phase intelligent version, the latest version is 22 at present, and the other is a next generation of an IOT scheme based on an IR46 method metering double-core table.

The existing 22-version single-phase intelligent meter is a single-core scheme, is not isolated by a metering and management MCU method, and can influence the work of a metering core when the MCU program is upgraded. The scheme of the built-in relay is adopted, replacement cannot be achieved, but the field operation failure rate of the relay assembly is high, the whole machine can only be replaced due to field failure, and the cost is high.

The existing single-phase Internet of things table scheme adopts a double-core scheme, and the normal work of a metering core is not influenced by the upgrading of a management core. The live wire of the main loop adopts manganin current sampling, the zero line adopts a mutual inductor current sampling scheme, a built-in relay is not arranged, and external circuit breakers are controlled through Bluetooth to realize load switching. But the cost of the complete machine plus the bluetooth breaker is high.

The existing manganin sampling technical scheme is as follows:

the advantages are that: the cost is low, alternating current and direct current can be sampled, the direct current and even harmonic influence resistance of 1.0L and 0.5L can be met, the structure is insensitive to the influence of external strong magnetism, and the occupied size of the structure is small.

The disadvantages are as follows: the large current heating is serious, the loss is large, the metering precision is influenced, the large current sampling device is not suitable for large current scheme application, the sampling precision is low, the high precision table type is not suitable, and the requirement of a level 1 table can only be met at present. The electric isolation is not needed, only the floating line can float, and the metering chip needs to be an electric isolation circuit.

The current traditional current transformer sampling technical scheme is as follows:

the advantages are that: the linearity is better than manganese sampling, the precision is higher, the primary side and the secondary side are electrically isolated, and a metering circuit does not need to be isolated independently.

The disadvantages are as follows: the overall cost is higher than that of the manganese copper scheme, and the direct current and even harmonic resistance can be generally met only under the condition of 1.0, if 0.5L is needed, the cost needs to be increased by about 50%. In addition, the magnetic shielding cover is sensitive to the influence of external strong magnetism, and needs to be added generally, so that the size is larger.

SUMMERY OF THE UTILITY MODEL

The purpose of the invention is as follows: the utility model aims to solve the technical problem that to prior art not enough, provide a single-phase thing of plug-in relay allies oneself with table based on zero magnetic flow active current sampling.

In order to solve the technical problem, the utility model discloses a single-phase thing of plug-in relay allies oneself with table based on zero magnetic flux active current sampling.

The Internet of things table comprises: a plug-in relay and a zero-flux current sensor; the zero-flux current sensor consists of a zero-flux transformer coil assembly, a signal conditioning circuit and a current sampling circuit; the signal conditioning circuit is matched with a zero flux transformer coil assembly to realize zero flux current sampling; in the signal conditioning circuit, zero magnetic flux active sampling is adopted.

The zero flux transformer coil assembly includes:

the starting end F1 of the induction compensation coil and the ending end F2 of the induction compensation coil; the start of the feedback coil S1 and the end of the feedback coil S2.

In the zero flux transformer coil assembly:

the initial end P1 of the input loop of the primary side circuit, the initial end F1 of the induction compensation coil and the initial end S1 of the feedback coil are homonymous ends; and the end P2 of the input loop of the primary circuit, the end F2 of the induction compensation coil and the end S2 of the feedback coil are synonym terminals.

The winding mode of the zero-flux transformer coil assembly is as follows:

the starting end P1 of the primary side circuit input loop and the ending end P2 of the primary side circuit input loop are the primary side circuit input loop, and the number of turns is 1 turn; the starting end F1 of the induction compensation coil and the ending end F2 of the induction compensation coil are induction compensation coils, the number of turns is 100 turns, the starting end S1 of the feedback coil and the ending end S2 of the feedback coil are feedback coils, and the number of turns is 2000 turns; the magnetic core adopts a green ring high-permeability core.

The signal conditioning circuit includes:

a first resistor R90, a second resistor R96, a third resistor R97, a fourth resistor R74, and a fifth resistor R88; a first capacitor C91, a second capacitor C83, a third capacitor C90, a fourth capacitor C75, and a fifth capacitor C77; a first dual diode device D14 and a second dual diode device D15; an operational amplifier chip U16;

the starting end F1 of the induction compensation coil is connected with the lower end of the first resistor R90 and the left end of the second resistor R96; the end F2 of the induction compensation coil is connected with the upper end of the first resistor R90; the upper end of the first resistor R90 is connected with an analog common ground AGND network; the pin 3 of the first double-diode device D14 is connected with the upper end of the first resistor R90;

pins

1 and 2 of the first bipolar device D14 are connected to the lower end of the first resistor R90 and the left end of the second resistor R96; the left end of the fourth resistor R74 is connected with an analog common ground AGND network; the right end of the fourth resistor R74 is connected with a pin 3 of the operational amplifier chip U16; the right end of the second resistor R96 is connected with the 4 pins of the operational amplifier chip U16, the third resistor R97 and the upper end of the first capacitor C91; the lower ends of the third resistor R97 and the first capacitor C91 are connected to the right end of the fifth resistor R88, the starting end S1 of the feedback coil, and the 3-pin of the second diode device D15; pin 1 of the second diode device D15 is connected to the negative supply-3.3V; the 2 pin of the second diode device D15 is connected to the positive supply + 3.3V; the left end of the fifth resistor R88 is connected with a pin 1 of the operational amplifier chip U16; the end S2 of the feedback coil is used for outputting a current signal Aout output by the signal conditioning circuit and is connected with the input end of the current sampling circuit; the pin 5 of the operational amplifier chip U16 is connected with the positive power supply plus 3.3V; the pin 2 of the operational amplifier chip U16 is connected with a negative power supply of-3.3V; the upper ends of the fourth capacitor C75 and the fifth capacitor C77 are connected with the positive power supply + 3.3V; the lower ends of the fourth capacitor C75 and the fifth capacitor C77 are connected with an analog common ground AGND network; the lower ends of the second capacitor C83 and the third capacitor C90 are connected with a negative power supply of-3.3V; the upper ends of the second capacitor C83 and the third capacitor C90 are connected to the analog common ground AGND network.

In the signal conditioning circuit, an operational amplifier chip U16, a second resistor R96, a third resistor R97, a first capacitor C91, a fourth resistor R74, a fifth resistor R88, a second capacitor C83, a third capacitor C90, a fourth capacitor C75 and a fifth capacitor C77 form a reverse amplification operation circuit.

The current sampling circuit includes:

a first magnetic bead L1 and a second magnetic bead L8; a sixth resistor R99, a seventh resistor R98, and an eighth resistor R129; a sixth capacitor C92, a seventh capacitor C94, and an eighth capacitor C93;

the left end of the first magnetic bead L1 is connected with the output current signal Aout of the signal conditioning circuit; the right end of the first magnetic bead L1 is connected with the upper end of a sixth resistor R99 and the left end of a seventh resistor R98; the left end of the second magnetic bead L8 is connected with the analog public grounding AGND network; the right end of the second magnetic bead L8 is connected with the lower end of the sixth resistor R99 and the left end of the eighth resistor R129; the right end of the seventh resistor R98 is connected with the upper end of the sixth capacitor C92 and the upper end of the eighth capacitor C93; the right end of the eighth resistor R129 is connected with the lower ends of the seventh capacitor C94 and the eighth capacitor C93; the lower end of the sixth capacitor C92 and the upper end of the seventh capacitor C94 are connected to the analog common ground AGND network.

In the current sampling circuit:

the seventh resistor R98 and the sixth capacitor C92 form an RC filter; the eighth resistor R129 and the seventh capacitor C94 form an RC filter; and a sixth capacitor C92 performs secondary filtering, and forms an anti-aliasing filtering circuit with the two RC filters.

The plug-in relay is installed in the single-phase internet of things meter in a plug-in mode.

The plug-in relay is designed according to the B-type module specification; the top is provided with a mark for distinguishing the switching-on and switching-off states of the relay; the lower part of the relay is provided with a strong current switching connection interface, the interface is 2 fixed copper bars, the copper bars are made of pure copper materials, the tail ends of the copper bars are chamfered by 15 degrees, the copper bars are subjected to tinning treatment, the average thickness is more than or equal to 80U ", the minimum thickness is more than or equal to 65U", and the tinning treatment adopts a lead-free process; the relay satisfies: the driving voltage is 12V, the coil power is 1.5W, the closing and opening time is less than 30ms, the contact resistance of the contact is less than 800u omega, the contact material is silver-nickel alloy, the withstand voltage of the contact is 2kV when the contact is opened, and the withstand voltage between the driving coil and the contact is 4kV.

Has the advantages that:

on current thing allies oneself with the table scheme, increase pluggable relay, need not external bluetooth circuit breaker, can realize the load switching function, reduce whole application cost. The design becomes pluggable relay, has solved the built-in relay scheme of traditional intelligence version, under the on-the-spot operation inefficacy condition, can't change the relay alone, need change the complete machine, reduces replacement cost and complexity.

The live wire adopts zero magnetic flux active current sampling technique, can solve original thing allies oneself with table manganin sampling heavy current self heating problem, reduces the consumption before the table, improves energy efficiency, reduces carbon and discharges. The sampling precision is high, the linearity is good, the precision of the full range and the full temperature region can reach 0.01 percent at most, the linearity can reach 0.01 percent, and secondary calibration is not needed. The bandwidth range is wide, and high-precision measurement can be realized within 30-100 KHZ. No saturation and no resonance. The transformer has the advantages of no insertion loss, simple structure, small volume and smaller volume than an equivalent range transformer. The phase difference is avoided, the input current and the output signal are synchronous, the direct current component is resisted, the magnetic isolation is realized, and the isolation of a post-stage circuit is not needed.

The zero magnetic flux current sampling technology and the pluggable relay combination are applied to the IOT, so that the problem that the relay cannot be replaced during field operation is solved, the problem of heating during manganin sampling is solved, the metering precision is improved, and the metering scheme is an ideal metering scheme for the single-phase IOT complete machine of the pluggable relay.

Drawings

These and/or other advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings and the following detailed description.

Fig. 1 is the overall schematic view of the internet of things table of the utility model.

Fig. 2 is a schematic diagram of a design principle of a zero-flux transformer.

Fig. 3 is a schematic winding diagram of a coil assembly of a zero-flux transformer.

Fig. 4 is a schematic diagram of a signal conditioning circuit.

Fig. 5 is a schematic diagram of the current sampling principle.

Fig. 6 is a schematic diagram of the voltage sampling principle.

Figure 7 is a schematic diagram of a pluggable relay installation.

Fig. 8 is a schematic diagram of a pluggable relay.

Fig. 9 is a schematic diagram showing the appearance and installation position of the zero-flux transformer coil assembly in the single-phase internet of things.

Figure 10 is a schematic view of the installation of the clip-on jack assembly and zero flux transformer.

Detailed Description

Because of the whole cost of current thing allies oneself with table + external bluetooth circuit breaker scheme is on the high side, for reducing whole scheme cost, has proposed an improved generation's thing allies oneself with table scheme, give the scheme that current thing allies oneself with table increase pluggable relay promptly, with the relay integration to the table end, make pluggable again, firstly can reduce whole scheme cost, secondly can solve the problem that the high unable independent change relay of the on-the-spot operation fault rate of the built-in relay of the prior art smart meter.

The scheme of the pluggable relay is to control a live wire line to realize load switching. The relay is made into a B-type module size and an interface, the pluggable connection can be realized only by slightly changing the structure of the ammeter, and the plugging position is the leftmost B-type module position. However, the pluggable scheme has the problem of large-current heating caused by certain contact resistance, which affects the metering precision, especially the large-current scheme, so that if the current sampling of the live wire still adopts a manganese-copper mode, the optimal selection is not achieved. Therefore, a metering scheme of a novel zero-flux active current sensor technology is designed, as shown in fig. 1:

the utility model discloses mainly optimize the innovation on current thing allies oneself with table basis, adopt the double-core chip of ten thousand high, with load identification module algorithm chip built-in, reduce external load identification B type module and use, vacate the position of B type module 1# for but plug-in relay's installation. Meanwhile, a zero-magnetic-flux current sampling technology is used on the electric meter for the first time, and the single-phase novel Internet of things meter is realized.

The utility model provides a thing allies oneself with table mainly includes 3 parts, management core part, measurement core part, function extension module part.

The management core part comprises an external battery circuit, and the super capacitor circuit realizes the power supply of the management core part circuit in a power failure state through a backup power supply switching circuit. The memory unit comprises a DATAFLASH circuit and an EEPROM circuit. The key detection circuit comprises a wheel display key and an open meter cover detection circuit. The display unit comprises a dot matrix liquid crystal display circuit, a backlight circuit and an LED indicating circuit. The local communication is in a Bluetooth communication mode and is used for local maintenance and calibration communication. The ESAM security chip is used for realizing the functions of the encryption algorithm. The relay driving unit circuit mainly comprises a relay driving circuit and a relay state detection circuit. The system comprises 2 groups of interfaces, one group of interfaces for communicating with a high-speed SPI of a metering core and one group of interfaces for communicating with a function expansion module.

The metering core portion comprises: the super capacitor circuit supplies power to the management core part circuit in a power failure state through the backup power supply switching circuit. The power failure detection circuit detects whether the electricity meter normally supplies power. The ESAM security chip is used for realizing the functions of the encryption algorithm. The terminal temperature measuring circuit is used for measuring the temperature of No. 1-4 current terminals. The memory unit comprises a DATAFLASH circuit and an EEPROM circuit. The optical pulse circuit is used for outputting the active and idle pulse signals. The metering sampling part comprises a voltage sampling circuit, an L-line zero magnetic flux sampling and signal conditioning circuit and an N-line mutual inductor sampling circuit.

The expansion module, each communication module interface design is overload or short-circuit protection, supports the hot plug. The expansion module comprises an A type module and a B type module, and an A type module interface is mainly used for accessing an HPLC (high performance liquid chromatography), 4G or 5G communication module. The B-type module interface is mainly used for the access of the B-type module load identification, the orderly charging and other expansion modules.

The utility model discloses mainly outstanding two points, but first plug relay (solve on-the-spot relay inefficacy and can only change the complete machine and ache the point), second adopts zero magnetic flow current sampling technique. (solving the problems of serious heating, narrow dynamic range and high DC cost resistance of 0.5L of the traditional mutual inductor in the manganin sampling mode)

The design scheme of the pluggable relay is as follows:

fig. 7 is a schematic diagram illustrating the installation position of the pluggable relay in the single-phase internet of things meter. The pluggable relay 7-1 is installed in a size consistent with a B-type module (refer to national power grid, technical specification of single-phase intelligent Internet of things electric energy meter), and the installation position is the 1# position of the B-type module, namely the leftmost position in the figure.

As shown in fig. 8, the appearance and installation size of the pluggable relay are consistent with those of the B-type module, and the interface of the weak current part of the module is consistent with the position of the weak current interface of the B-type module, and the pluggable relay is mainly used for connecting the driving coil of the relay and connecting the detection signal of the switching-on or switching-off state of the relay. The position of the small square block at the top of the relay module is knowledge of the switching-on or switching-off state of the relay, the knowledge is designed into an LED indication mode or a color block mode for indication, when the LED indicates a scheme, the LED is in the switching-on state when being green, the LED is in the switching-off state when being red, when the color block scheme is adopted, the square block displays that the LED is in the switching-on state when being green, and the square block window displays that the LED is in the switching-off state when being red.

Increase the forceful electric power and switch over the connection interface, for 2 fixed copper bars, the copper bar is pure copper material, terminal chamfer 15, the partial tinning of copper bar, the cladding material: and (4) tinning, wherein the average thickness value is more than or equal to 80U ", and the minimum value is more than or equal to 65U", and a lead-free process is adopted. Design parameters of the relay: the driving voltage is 12V, the coil power is 1.5W, the closing and opening time is less than 30ms, the contact resistance of the contact is less than 800u omega, the contact material is silver-nickel alloy, the withstand voltage of the contact is 2kV when the contact is opened, and the withstand voltage between the driving coil and the contact is 4kV, so that the current impact endurance level UC2 of the relay is met.

As shown in fig. 9, which is an appearance of a coil assembly 9-2 of the zero-flux transformer and an installation position diagram of a single-phase internet of things meter, a terminal box has 4 sets of current connection terminals, which are No. 1,2,3,4 from left to right, when the electricity meter is used for field wiring, the No. 1 terminal is used for connecting an incoming line end of a live wire L to a power supply grid, and the No. 2 terminal is used for connecting an output end of the live wire L to a user load end. The No. 3 terminal is an incoming line end of a zero line N and connected with a power supply grid, and the No. 4 terminal is an output end of the zero line N and connected with a user load end.

The No. 1 current terminal is welded with a copper bar in a butt joint mode, the copper bar penetrates through the starting end P1 end of a primary circuit input loop of a zero-flux transformer coil assembly and is output from the end P2 end of the primary circuit input loop, the tail end of the copper bar output is designed into a clamping piece type elastic socket mode, the No. 2 current terminal is welded with the copper bar in a butt joint mode, and the tail end of the copper bar output is also designed into a clamping piece type elastic socket mode. The elastic socket is used for inserting the relay switching copper bar, and two ends of the relay switching copper bar can be understood as a switch, so that switching-on and switching-off of a live wire are achieved, and power supply and switching-off of a user are achieved.

The pluggable relay clamping piece type elastic socket component 9-1 is made of phosphor bronze alloy. Design into upper end funnel type interface, be favorable to the relay to insert, design into multiunit wavy mode and be favorable to improving the clamping force that clamping piece elasticity increases the relay copper bar, shell fragment wave design, middle opening is 2 groups side by side, the area of contact that 3 horizontal contact point designs of every group can increase copper bar and socket reduces contact impedance and generate heat, improve the ability of overflowing, design into 2 parallel modes of group of middle opening, do benefit to and reduce deformation in the installation, guarantee that the contact surface does not reduce.

As shown in fig. 10, the perspective view of the installation of the pluggable relay, the clip type resilient socket assembly 10-1 and the zero flux transformer:

the No. 1 current terminal is a current incoming line terminal, the copper bar of the No. 1 terminal penetrates through the starting end P1 of a primary circuit input loop of the zero-crossing magnetic flux transformer assembly, the finishing end P2 of the primary circuit input loop is out, the elastic socket is connected to a clamping piece type elastic socket at the tail end of an output end, the elastic socket is connected to a strong current copper bar of a relay incoming line terminal, the strong current copper bar of a relay outgoing line terminal is connected to the clamping piece type elastic socket at the tail end of the copper bar of the No. 2 current terminal and is connected with the No. 2 current terminal, therefore, the No. 1 current terminal is connected, the current flows through the relay change-over switch, the current is output from the No. 2 current terminal, and meanwhile, the circuit penetrates through the zero-crossing magnetic flux transformer assembly to achieve zero-flux current sampling.

The utility model discloses in, carry out the current sampling through zero magnetic current sensor, zero magnetic current sensor comprises zero magnetic current transformer coil pack and signal conditioning circuit.

The zero-flux transformer coil assembly is provided with a group of coils compared with a common transformer, and consists of two groups of coils and a magnetic core, wherein one group of coils is an induction compensation coil, and the other group of coils is a feedback coil. When alternating current appears on the primary side, the feedback coil can mutually induce corresponding current, the induction coil compensates the feedback coil through a circuit to enable the magnetic field on the magnetic core to be zero and achieve zero magnetic flux, and the current sum on the feedback coil is equal to the current on the primary side at the moment. The primary side current can be accurately calculated by detecting the single smashing current on the feedback coil and then through the total smashing number.

The design principle of the zero-flux transformer is shown in fig. 2, wherein P1 is the starting end of the input loop of the primary circuit, P2 is the ending end of the input loop of the primary circuit, F1 is the starting end of the induction compensation coil, F2 is the ending end of the induction compensation coil, S1 is the starting end of the feedback coil, and S2 is the ending end of the feedback coil.

The zero magnetic flux transformer coil assembly winding mode has the design specification of 5 (100) A/2.5mA,0.05A-100A full-range precision of 0.01 percent and meets the design turn number of an IOT (in-flight data acquisition) table. P1-P2 are primary circuit input loops, the number of turns is 1 turn, F1-F2 are induction compensation coils, in this embodiment, the number of turns is 100 turns, S1-S2 are feedback coils, in this embodiment, the number of turns is 2000 turns, and the magnetic core is a green-ring high-permeability core. When winding, F1 and F2 of the induction compensation coil are wound first, and then feedback coils S1 and S2 are wound, wherein the initial end P1 of the input loop of the primary circuit, the initial end F1 of the induction compensation coil and the initial end S1 of the feedback coil are homonymy ends; the end P2 of the input loop of the primary circuit, the end F2 of the induction compensation coil and the end S2 of the feedback coil are synonym ends. The specific winding is shown in a schematic diagram 3.

The signal conditioning circuit in the zero flux current sensor is shown in fig. 4:

description of the principle:

CT1 is a mutual inductor coil assembly, F1-F2 are induction coil windings, S1-S2 are feedback coil windings, induced currents generated by the induction coils F1-F2 are subjected to voltage sampling through a sampling first resistor R90, and sampling signals are connected to the negative end of the inverse operational amplification circuit to be amplified. (wherein the operational amplifier chip U16, the second resistor R96, the third resistor R97, the first capacitor C91, the fourth resistor R74, the fifth resistor R88, the second capacitor C83, the third capacitor C90, the fourth capacitor C75 and the fifth capacitor C77 form a reverse amplification operation circuit.)

The output signal of the induction coil amplified by the operational amplifier circuit compensates the feedback coil to make the magnetic field on the magnetic core zero and achieve zero magnetic flux, and the current sum on the feedback coil is equal to the primary current at the moment. The feedback coil outputs a current signal, the current sampling circuit is connected, the sampling resistor, namely the sixth resistor R99, converts the current signal into a voltage signal, the voltage signal is connected to a current input sampling channel of the metering chip, and the current value measurement can be realized through the processing of the metering chip.

Aiming at different metering chips, the output signal of the conditioning circuit needs to meet the requirement of the metering chip on the sampling channel range, and the actual adjustment can be carried out according to the metering chip, and the maximum input peak-to-peak value of the chip is 200mV, so the designed maximum input current value is within 200mV peak-to-peak value and cannot overflow.

Description of electrical connection:

d14 is a first double-diode device, D15 is a second double-diode device, the first double-diode device D14 performs amplitude limiting protection on the output of the induction coil winding, D15 the second double-diode device performs amplitude limiting protection on the dotted end of the feedback coil winding, and the first resistor R90 is an induction coil current sampling resistor. The operational amplifier chip U16, the second resistor R96, the third resistor R97, the first capacitor C91, the fourth resistor R74, the fifth resistor R88, the second capacitor C83, the third capacitor C90, the fourth capacitor C75 and the fifth capacitor C77 form a reverse amplification operation circuit, the operational amplifier chip U16, the operational amplifier circuit positive power supply decoupling capacitors for the fourth capacitor C75 and the fifth capacitor C77, and the operational amplifier circuit negative power supply decoupling capacitors for the second capacitor C83 and the third capacitor C90. The second resistor R96 and the third resistor R97 are operational amplifier gain configuration resistors, and the first capacitor C91 is a compensation capacitor for phase compensation, preventing oscillation, and suppressing high frequency noise. The fourth resistor R74 is a balancing resistor to provide a proper static bias for the circuit.

The starting end F1 of the induction compensation coil is respectively connected with the lower end of a sampling resistor, namely a first resistor R90 and the left end of a second resistor R96. An end terminal F2 of the induction compensation coil is connected with the upper end of a first resistor R90 which is a sampling resistor, the upper end of the first resistor R90 is connected with an analog common ground AGND network, a pin 3 of a first double-diode device D14 is connected with the upper end of the first resistor R90, and a pin 1 and a pin 2 of the first double-diode device D14 are respectively connected with the lower end of the first resistor R90 and the left end of a second resistor R96. The left end of a fourth resistor R74 is connected with the analog common ground AGND network, the right end of the fourth resistor R74 is connected with the pin 3 of the operational amplifier chip U16, the right end of a second resistor R96 is respectively connected with the pin 4 of the operational amplifier chip U16, the third resistor R97 and the upper end of a first capacitor C91, the lower ends of the third resistor R97 and the first capacitor C91 are respectively connected with the right end of a fifth resistor R88, the starting end S1 of the feedback coil and the pin 3 of a second bipolar device D15, the pin 1 of the second bipolar device D15 is connected with a negative power supply of-3.3V, and the pin 2 of the second bipolar device D15 is connected with a positive power supply of + 3.3V. The left end of the fifth resistor R88 is connected with pin 1 of the operational amplifier chip U16, and the end S2 end of the feedback coil is connected with the input end of the current sampling circuit for outputting the current signal Aout of the signal conditioning circuit. The 5 pin of the operational amplifier chip U16 is connected with the positive power supply of 3.3V, and the 2 pin of the operational amplifier chip U16 is connected with the negative power supply of 3.3V. The upper ends of the fourth capacitor C75 and the fifth capacitor C77 are connected with the positive power supply +3.3V, and the lower ends of the fourth capacitor C75 and the fifth capacitor C77 are connected with the analog common ground AGND network. The lower ends of the second capacitor C83 and the third capacitor C90 are connected with a negative power supply of-3.3V, and the upper ends of the second capacitor C83 and the third capacitor C90 are connected with an analog common ground AGND network.

The metering implementation mode is as follows: through peripheral sampling circuit, sample voltage signal and current signal, and insert the voltage and the electric current simulation passageway of measurement chip, handle through the inside DSP of measurement chip, can realize the magnitude of voltage and measure, the current value is measured, calculate the voltage current phase angle, power factor, voltage frequency, detect out the direction of current, and can calculate apparent power, active power, reactive power, measurement chip handles according to the integral of power to time, can calculate visual power electric energy, positive reverse active electric energy, positive reverse reactive electric energy, configure into required algebra and or absolute value measurement mode according to measurement chip internal register, thereby realize a complete measurement mode, the utility model discloses the absolute value measurement mode of mainly using.

Fig. 5 is a current sampling circuit, in the whole utility model, realizes measurement current signal sampling function.

The signal conditioning circuit outputs a current signal Aout to the analog common ground AGND network through the first magnetic bead L1, the sixth resistor R99, and the second magnetic bead L8. The current signal flows through the sixth resistor R99, generating a voltage drop, thereby converting the current signal into a voltage signal. The seventh resistor R98 and the sixth capacitor C92 form an RC filter, the eighth resistor R129 and the seventh capacitor C94 form an RC filter, the sixth capacitor C92 performs secondary filtering, the two RC filters and the sixth capacitor C92 form an anti-aliasing filtering circuit, high-frequency signals or noise are filtered, and useful signals are sent to the current analog sampling channel of the metering chip.

Description of electrical connection: the left end of the first magnetic bead L1 is connected with the output current signal Aout of the signal conditioning circuit, and the right end of the first magnetic bead L1 is connected with the upper end of the sixth resistor R99 and the left end of the seventh resistor R98 respectively. The left end of the second magnetic bead L8 is connected with the analog common ground AGND network, and the right end of the second magnetic bead L8 is connected with the lower end of the sixth resistor R99 and the left end of the eighth resistor R129 respectively. The right end of the seventh resistor R98 is respectively connected with the upper end of the sixth capacitor C92 and the upper end of the eighth capacitor C93, the right end of the eighth resistor R129 is respectively connected with the lower end of the seventh capacitor C94 and the lower end of the eighth capacitor C93, and the lower end of the sixth capacitor C92 and the upper end of the seventh capacitor C94 are connected with the analog common ground AGND network.

Fig. 6 is a voltage sampling circuit, in whole utility model, realizes measurement voltage signal sampling function.

The voltage sampling circuit is realized by adopting resistance voltage division, one end of the voltage sampling circuit is connected with the N end of a zero line, the other end of the voltage sampling circuit is connected with the L end of a live line, and the L end of the live line is connected with the analog public grounding AGND of the metering chip in a float line mode. The differential sampling mode is designed, the positive sampling terminal UP is taken out from the upper end of the ninth resistor R135, and the negative sampling terminal UP is taken out from the lower end of the tenth resistor R136. The ninth capacitor C95 and the tenth capacitor C96 are filter capacitors.

Description of electrical connection: the zero line N is connected with the left end of an eleventh resistor R133, the right end of an eleventh resistor R133 is connected with the left end of a twelfth resistor R131, the right end of a twelfth resistor R131 is connected with the left end of a thirteenth resistor R132, the right end of a thirteenth resistor R132 is connected with the left end of a fourteenth resistor R128, the right end of the fourteenth resistor R128 is connected with the left end of a fifteenth resistor R134, the right end of a fifteenth resistor R134 is connected with the left end of a sixteenth resistor R130, the right end of the sixteenth resistor R130 is respectively connected with the upper end of a ninth resistor R135 and the upper end of a ninth capacitor C95 and connected to an UP end of a metering chip, and the lower end of the ninth resistor R135 is connected with the lower end of the ninth capacitor C95 and an AGND network. The upper end of the tenth resistor R136 and the upper end of the tenth capacitor C96 are connected with the analog common ground AGND network, and the lower ends of the tenth resistor R136 and the tenth capacitor C96 are connected with the end of the metering chip UN.

The utility model provides a thought and method of single-phase thing allies oneself with table of plug-in relay based on zero magnetic flux active current sampling specifically realize this technical scheme's method and way many, above only the utility model discloses a preferred embodiment should point out, to the ordinary technical staff in this technical field, does not deviate from the utility model discloses under the prerequisite of principle, can also make a plurality of improvements and moist decorations, these improve and moist decorations should also regard as the utility model discloses a scope of protection. All the components not specified in this embodiment can be implemented by the prior art.

Claims

1. The utility model provides a single-phase thing allies oneself with table of plug-in relay based on zero magnetic flux active current sampling which characterized in that, include in the thing allies oneself with the table: a plug-in relay and a zero-flux current sensor; the zero-flux current sensor consists of a zero-flux transformer coil assembly, a signal conditioning circuit and a current sampling circuit; the signal conditioning circuit is matched with a zero-flux transformer coil assembly to realize zero-flux current sampling; in the signal conditioning circuit, zero magnetic flux active sampling is adopted.

2. The zero-flux active current sampling based plug-in relay single-phase Internet of things table as claimed in claim 1, wherein the zero-flux transformer coil assembly comprises:

an induction compensation coil, comprising: the starting end F1 of the induction compensation coil and the ending end F2 of the induction compensation coil; a feedback coil, comprising: a start end S1 of the feedback coil and an end S2 of the feedback coil.

3. The zero-flux active current sampling based plug-in relay single-phase internet of things table according to claim 2, wherein in the zero-flux transformer coil assembly:

the initial end P1 of the input loop of the primary circuit, the initial end F1 of the induction compensation coil and the initial end S1 of the feedback coil are homonymous ends; and the end P2 of the input loop of the primary circuit, the end F2 of the induction compensation coil and the end S2 of the feedback coil are synonym terminals.

4. The zero-flux active current sampling-based plug-pull relay single-phase Internet of things table as claimed in claim 3, wherein the zero-flux transformer coil assembly is wound in the following manner:

the starting end P1 of the primary side circuit input loop and the ending end P2 of the primary side circuit input loop are primary side circuit input loops; the starting end F1 of the induction compensation coil and the ending end F2 of the induction compensation coil are induction compensation coils, and the starting end S1 of the feedback coil and the ending end S2 of the feedback coil are feedback coils; the magnetic core adopts a green ring high-permeability core.

5. The zero-flux active current sampling based plug-in relay single-phase Internet of things table according to claim 4, wherein the signal conditioning circuit comprises:

the starting end F1 of the induction compensation coil is connected with the lower end of the first resistor R90 and the left end of the second resistor R96; the end F2 of the first induction compensation coil is connected with the upper end of the first resistor R90; the upper end of the first resistor R90 is connected with an analog common ground AGND network; the pin 3 of the first double-diode device D14 is connected with the upper end of the first resistor R90; pins 1 and 2 of the first bipolar device D14 are connected to the lower end of the first resistor R90 and the left end of the second resistor R96; the left end of the fourth resistor R74 is connected with an analog common ground AGND network; the right end of the fourth resistor R74 is connected with a pin 3 of the operational amplifier chip U16; the right end of the second resistor R96 is connected with the 4 pins of the operational amplifier chip U16, the third resistor R97 and the upper end of the first capacitor C91; the lower ends of the third resistor R97 and the first capacitor C91 are connected to the right end of the fifth resistor R88, the starting end S1 of the feedback coil, and the 3-pin of the second diode device D15; pin 1 of the second diode device D15 is connected to the negative supply-3.3V; the 2 pin of the second diode device D15 is connected to the positive supply + 3.3V; the left end of the fifth resistor R88 is connected with a pin 1 of the operational amplifier chip U16; the end S2 of the feedback coil is used for outputting a current signal Aout output by the signal conditioning circuit and is connected with the input end of the current sampling circuit; the 5 pins of the operational amplifier chip U16 are connected with the positive power supply plus 3.3V; the pin 2 of the operational amplifier chip U16 is connected with a negative power supply of-3.3V; the upper ends of the fourth capacitor C75 and the fifth capacitor C77 are connected with the positive power supply + 3.3V; the lower ends of the fourth capacitor C75 and the fifth capacitor C77 are connected with an analog common ground AGND network; the lower ends of the second capacitor C83 and the third capacitor C90 are connected with a negative power supply of-3.3V; the upper ends of the second capacitor C83 and the third capacitor C90 are connected to the analog common ground AGND network.

6. The plug-in relay single-phase object-linked list based on zero-magnetic-flux active current sampling is characterized in that in the signal conditioning circuit, an operational amplifier chip U16, a second resistor R96, a third resistor R97, a first capacitor C91, a fourth resistor R74, a fifth resistor R88, a second capacitor C83, a third capacitor C90, a fourth capacitor C75 and a fifth capacitor C77 form a reverse amplification operation circuit.

7. The zero-flux active current sampling-based plug-pull relay single-phase Internet of things table as claimed in claim 6, wherein the current sampling circuit comprises:

first magnetic beads L1 and second magnetic beads L8; a sixth resistor R99, a seventh resistor R98, and an eighth resistor R129; a sixth capacitor C92, a seventh capacitor C94, and an eighth capacitor C93;

the left end of the first magnetic bead L1 is connected with the output current signal Aout of the signal conditioning circuit; the right end of the first magnetic bead L1 is connected with the upper end of a sixth resistor R99 and the left end of a seventh resistor R98; the left end of the second magnetic bead L8 is connected with the analog public grounding AGND network; the right end of the second magnetic bead L8 is connected with the lower end of a sixth resistor R99 and the left end of an eighth resistor R129; the right end of the seventh resistor R98 is connected with the upper end of the sixth capacitor C92 and the upper end of the eighth capacitor C93; the right end of the eighth resistor R129 is connected with the lower ends of the seventh capacitor C94 and the eighth capacitor C93; the lower end of the sixth capacitor C92 and the upper end of the seventh capacitor C94 are connected to the analog common ground AGND network.

8. The plug-in relay single-phase Internet of things table based on zero-flux active current sampling is characterized in that in the current sampling circuit:

9. The zero-flux active current sampling based plug-in relay single-phase physical connection meter according to claim 8, characterized in that the plug-in relay is installed in the single-phase physical connection meter in a plug-in manner.

10. The zero-flux active current sampling-based plug-in relay single-phase Internet of things table as claimed in claim 9, wherein the plug-in relay is designed according to B-type module specifications; the top is provided with a mark for distinguishing the switching-on and switching-off states of the relay; the lower part of the relay is provided with a strong current switching connection interface, the interface is 2 fixed copper bars, the copper bars are made of pure copper materials, the tail ends of the copper bars are chamfered by 15 degrees, the copper bars are subjected to tinning treatment, the average thickness is more than or equal to 80U ", the minimum thickness is more than or equal to 65U", and the tinning treatment adopts a lead-free process; the relay satisfies: the driving voltage is 12V, the coil power is 1.5W, the closing and opening time is less than 30ms, the contact resistance of the contact is less than 800u omega, the contact material is silver-nickel alloy, the withstand voltage of the contact is 2kV when the contact is opened, and the withstand voltage between the driving coil and the contact is 4kV.