CN211293068U - Novel three-phase multifunctional intelligent electric energy meter - Google Patents

Novel three-phase multifunctional intelligent electric energy meter Download PDF

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CN211293068U
CN211293068U CN201922092678.8U CN201922092678U CN211293068U CN 211293068 U CN211293068 U CN 211293068U CN 201922092678 U CN201922092678 U CN 201922092678U CN 211293068 U CN211293068 U CN 211293068U
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voltage
power
signal
chip
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孟祥梯
万留美
唐永新
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Shenzhen Eybond Co ltd
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Shenzhen Eybond Co ltd
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Abstract

The utility model discloses a novel three-phase multifunctional intelligent electric energy meter, which comprises a power panel, a signal board electrically connected with the power panel and a voltage transformer electrically connected with the signal board; the power panel is connected with a power chip T1 and a transformer T2 in a circuit, alternating current 220V-to-4.5V output is achieved through the power chip T1 and the transformer T2, a 4.5V output end is electrically connected with a voltage stabilizing chip U3, the voltage stabilizing chip U3 is converted into 3.3V voltage output required by the work of a main control IC on the signal panel, the 3.3V voltage output end is transmitted to the three-phase signal panel through a J1 terminal, a voltage transformer is arranged on the power panel, a power grid voltage signal is converted into a small current signal through the voltage transformer, and the small current signal is transmitted to the main control IC through a J3 interface to be subjected to voltage measurement; the three-phase signal board is provided with master control IC. The utility model discloses the circuit of intelligent ammeter is simplified, and the reliability improves.

Description

Novel three-phase multifunctional intelligent electric energy meter
Technical Field
The utility model relates to an intelligent electric energy meter, specific saying so relates to a novel multi-functional intelligent electric energy meter of three-phase.
Background
The existing electric energy meters are generally divided into mechanical type and electronic type. The mechanical electric energy meter consists of a measuring mechanism, a compensation adjusting device and auxiliary components (a shell, a rack, an end button box and a nameplate), and has a service life problem because of mechanical transmission and transfer of the mechanical electric energy meter, and the mechanical electric energy meter is difficult to simultaneously take multiple functions of time-sharing metering, load control, parameter presetting, acquisition, storage, real-time transmission and the like.
The electronic electric energy meter has no mechanical transmission structure, so that it has greatly prolonged service life, and its electronic parts have metering and storing functions, monitoring function and management function. However, the electronic electric energy meter also has the problems of incapability of realizing remote centralized management, complex product circuit, high cost, incapability of meeting the requirements of electricity buying and selling measurement and the like. Meanwhile, different products are designed and developed aiming at three phases and high current, and the research and development cost is high.
SUMMERY OF THE UTILITY MODEL
To the deficiency among the prior art, the to-be-solved technical problem of the utility model lies in providing a novel multi-functional intelligent electric energy meter of three-phase, the purpose of designing the hardware circuit structure of this intelligent electric energy meter is: and the metering of three-phase large current is realized through a three-phase signal plate.
In order to solve the technical problem, the utility model discloses a following scheme realizes: the utility model discloses a novel three-phase multifunctional intelligent electric energy meter, which comprises a power panel, a signal board electrically connected with the power panel and a voltage transformer electrically connected with the signal board;
the power panel is characterized in that a circuit on the power panel is connected with a power chip T1 and a transformer T2, the output of converting alternating current 220V into 4.5V is realized through the power chip T1 and the transformer T2, a 4.5V output end is electrically connected with a voltage stabilizing chip U3, the voltage stabilizing chip U3 is converted into 3.3V voltage output required by the work of a main control IC on the signal panel, the 3.3V voltage output end is transmitted to the signal panel through a J1 terminal, the transformer T2 is further provided with a 5V output circuit, the 5V output circuit is transmitted to a bidirectional transceiver U6 on the power panel for power supply, and the power panel is further provided with an isolation output circuit;
the voltage transformer is arranged on the power panel, and a power grid voltage signal is converted into a small current signal through the voltage transformer and is sent to the main control IC through the J3 interface for voltage measurement;
the signal board is a three-phase main control board, and a main control IC for metering signal processing, display output, pulse output and RS485 communication signal output is arranged on the signal board;
the power panel is connected with three-phase power, and three-phase voltage signals of a power grid are converted into small current signals through a voltage transformer PT1, a voltage transformer PT2 and a voltage transformer PT3 and are sent to the master control IC through a J3 interface to be subjected to voltage measurement.
Further, an optical coupler E1, an optical coupler E2 and an optical coupler IC5 which are connected to the 3.3V voltage output end are further arranged on the power panel, the bidirectional transceiver U6 is used for converting one path of serial ports of the signal panel into an RS485 circuit, signal isolation transmission is achieved through the optical coupler E1 and the optical coupler E2, and finally pulse signals are isolated and output to the outside through the optical coupler IC 5.
Further, the signal board comprises a three-phase signal board connected to a three-phase power supply board.
Furthermore, in the three-phase signal board, the master control IC thereon includes three-phase metering chip U2 and single-phase metering chip U1, and the power passes through the J2 interface and follows the power strip sends into the three-phase signal board, and the electric current after the three-phase voltage conversion passes through the J3 interface and reaches the three-phase signal board, and the three-phase electric current passes through voltage transformer PT1 respectively, voltage transformer PT2, voltage transformer PT3 back respectively through VA1, VB1, three-phase metering chip U2 on the three-phase signal board of VC1 access, and three-phase metering chip U2 carries out data transmission with single-phase metering chip U1 through the SPI interface.
Furthermore, the single-phase metering chip U1 is only used for display and serial port communication when being matched with the three-phase metering chip U2 for use.
Further, an LCD display screen JH1 is arranged on the three-phase signal board, the LCD display screen JH1 is used for displaying the numerical values of current, voltage, power, electric energy and frequency measured by the electric energy meter, a 26-pin CF1 of the three-phase metering chip U2 is in pulse output, and the LED2 is a power indicator lamp.
Compared with the prior art, the beneficial effects of the utility model are that: the utility model discloses an intelligent ammeter is the three-phase intelligent ammeter through adopting newest low-power consumption, high performance, high integration degree, the special measurement chip of high reliability to come the development. The utility model discloses a three-phase smart electric meter passes through main control chip and accomplishes measurement, storage, demonstration, communication and pulse function, and the product circuit is simplified, and the reliability improves, and this product can also insert the internet through RS485 circuit and outside equipment simultaneously, realizes remote management and control function, possesses forward and reverse current measurement function simultaneously. Meanwhile, the technical design of the electric energy meter adopts a modular design, and the metering of three-phase heavy current is realized through a three-phase signal plate.
Drawings
Fig. 1 is the utility model discloses intelligent ammeter's hardware circuit structure connection block diagram.
Fig. 2 is a circuit diagram of the three-phase power board of the present invention, in which a power chip T1 is connected to a transformer T2.
Fig. 3 is a circuit diagram of the voltage stabilizing chip U3 in the three-phase power board of the present invention.
Fig. 4 is a circuit diagram of a bidirectional transceiver U6 in the three-phase power board of the present invention.
Fig. 5 is a circuit diagram of an optical coupler E2 in the three-phase power board of the present invention.
Fig. 6 is a circuit diagram of an optocoupler IC5 in the three-phase power board of the present invention.
Fig. 7 is a circuit diagram of an optical coupler E1 in the three-phase power board of the present invention.
Fig. 8 is a circuit diagram of the three-phase power board of the present invention, in which the CF1 output is connected to the three-phase signal board.
Fig. 9 is the utility model discloses in the three-phase power strip, voltage transformer PT1, voltage transformer PT2 and voltage transformer PT3 circuit diagram.
Fig. 10 is a circuit diagram of a J1 terminal of the three-phase power board of the present invention.
Fig. 11 is a circuit diagram of an interface J3 in the three-phase power board of the present invention.
Fig. 12 is a circuit diagram of a single-phase metering chip U1 in the three-phase signal board of the present invention.
Fig. 13 is an enlarged view of the left side circuit of fig. 12.
Fig. 14 is a circuit diagram of a three-phase metering chip U2 in the three-phase signal board of the present invention.
Fig. 15 is the three current detection circuit diagram connected with the three-phase metering chip U2 in the three-phase signal board of the present invention.
Fig. 16 is the utility model discloses in the three-phase signal board, the three voltage detection circuit diagram of being connected with voltage transformer PT1, voltage transformer PT2 and voltage transformer PT3 respectively.
Fig. 17 is a circuit diagram of the LCD display JH1 in the three-phase signal board of the present invention.
Detailed Description
The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making more clear and definite definitions of the protection scope of the present invention. It is obvious that the described embodiments of the invention are only some of the embodiments of the invention, and not all of them. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; the two elements may be directly connected or indirectly connected through an intermediate medium, or may be communicated with each other inside the two elements, or may be wirelessly connected or wired connected. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Furthermore, the technical features mentioned in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.
Embodiment 1, the utility model discloses a specific structure as follows:
referring to fig. 1-17, the utility model discloses a novel three-phase multifunctional intelligent electric energy meter, including power panel 1, signal board 2 electrically connected with the power panel 1 and voltage transformer 3 (fig. 1) electrically connected with the signal board 2, power chip T1 and transformer T2 (fig. 2) are connected in the circuit on the power panel 1, through power chip T1 with the transformer T2 realize exchanging 220V and changing 4.5V output, 4.5V output end is electrically connected with voltage stabilization chip U3 (fig. 3), the voltage stabilization chip U3 changes the 3.3V voltage output that the main control IC work on the signal board 2 needs, 3.3V voltage output end is transmitted to the signal board 2 through J1 terminal (fig. 10), the transformer T2 is still equipped with 5V output circuit, this 5V output circuit is transmitted to the bidirectional transceiver U6 (fig. 4) on the power panel 1 for power supply, the power panel 1 is also provided with an isolated output circuit;
the voltage transformer 3 (shown in fig. 9) is arranged on the power panel 1, and a power grid voltage signal is converted into a small current signal through the voltage transformer 3 and is sent to the master control IC through a J3 interface (shown in fig. 11) to be subjected to voltage measurement;
the signal board 2 is a three-phase main control board, and a main control IC used for measuring signal processing, display output, pulse output and RS485 communication signal output is arranged on the signal board.
A preferred technical solution of this embodiment: the power panel 1 is further provided with an optical coupler E1 (fig. 7), an optical coupler E2 (fig. 5) and an optical coupler IC5 (fig. 6) which are connected to the 3.3V voltage output end, the bidirectional transceiver U6 (fig. 4) realizes that one path of serial port of the signal panel 2 is converted into an RS485 circuit, signal isolation transmission is realized through the optical coupler E1 (fig. 7) and the optical coupler E2 (fig. 5), and finally, pulse signals are isolated and output to the outside through the optical coupler IC5 (fig. 6), so that the isolation output circuit is formed.
A pin 2 of an optical coupler E1 (figure 7) is connected with a pin TX of a J3 interface in a three-phase power panel, a pin 1 is connected with 3.3V voltage, a pin 3 is grounded, a pin 4 is respectively connected with a resistor and a pin TX (MCU) connecting end of a single-phase metering chip U1 connected in a three-phase signal panel, and the other end of the resistor is connected with 5V voltage.
The 4 feet of the optical coupler E2 (figure 5) are connected with a TX foot of a J3 interface and a resistor R5 in a three-phase power panel, the 1 foot of the optical coupler E2 is connected with 2.5V voltage, the 3 feet of the optical coupler E2 are grounded, the 2 feet of the optical coupler E2 are connected with a resistor R4, the other end of the resistor R4 is connected with a TX (MCU) connecting end of a single-phase metering chip U1 in a three-phase signal panel, and the other end of the resistor R5 is connected with 3.3V voltage.
A negative electrode end of a light emitting diode at one end of an optical coupler IC5 (shown in figure 6) is connected with a CF1-MCU connecting end, a CF1-MCU connecting end is connected with a collector of an NPN triode Q11 (shown in figure 8), an emitter of the NPN triode Q11 is grounded, a base of the NPN triode Q11 is connected with a CF1 connecting end, a CF1 connecting end is connected with a light emitting LED1 on a three-phase metering chip U2, the other end of the light emitting LED1 is connected with a resistor R390, the other end of the resistor R390 is connected with a 26 pin of the three-phase metering chip U2, a collector at the other end of the optical coupler IC5 is connected with a P + I connecting end, an emitter at the other end of the optical coupler IC 63.
As shown in fig. 2 to 11, a preferred technical solution of this embodiment: the power panel 1 is connected with three-phase power or single-phase power;
when the power panel 1 is connected with three-phase power, a three-phase voltage signal of a power grid is converted into a small current signal through a voltage transformer PT1, a voltage transformer PT2 and a voltage transformer PT3 (shown in figure 9), and the small current signal is sent to the master control IC through a J3 interface to carry out voltage measurement; one end VA1 and VAN of the voltage transformer PT1 are connected with a current detection circuit [ fig. 16 ], one end VB1 and VBN of the voltage transformer PT2 are connected with a current detection circuit [ fig. 16 ], and one end VC1 and VCN of the voltage transformer PT3 are connected with a current detection circuit [ fig. 16 ]. The current detection circuit is used for detecting the current of each voltage transformer.
As shown in fig. 12-13, a preferred technical solution of this embodiment: the signal board 2 comprises a three-phase signal board connected into a three-phase power supply board.
A preferred technical solution of this embodiment: in the three-phase signal plate, a master control IC on the three-phase signal plate comprises a three-phase metering chip U2 (shown in fig. 14) and a single-phase metering chip U1 (shown in fig. 12-13), a power supply is sent into the three-phase signal plate from the power supply plate 1 through a J2 interface (consistent with a J1 terminal structure), currents after three-phase voltage conversion are transmitted to the three-phase signal plate through a J3 interface (shown in fig. 11), the three-phase currents are respectively connected to the three-phase metering chip U2 on the three-phase signal plate through three terminals of a voltage transformer PT1, a voltage transformer PT2 and a voltage transformer PT3 (shown in fig. 9) respectively through three terminals of a VA1, a VB1 and a VC1, and the three-phase metering chip U2 (shown in fig. 14) performs data transmission with the single-phase metering chip U1 (shown in fig. 12-13) through an SPI interface.
A preferred technical solution of this embodiment: when the single-phase metering chip U1 and the three-phase metering chip U2 are used in a matching mode, the single-phase metering chip U1 only serves as display and serial port communication.
A preferred technical solution of this embodiment: an LCD display screen JH1 (shown in figure 17) is arranged on the three-phase signal board, the LCD display screen JH1 is used for displaying the numerical values of current, voltage, power, electric energy and frequency measured by the electric energy meter, a 26-pin CF1 of the three-phase metering chip U2 is pulse output, and the LED2 is a power indicator lamp.
Example 2:
the preferred models adopted by the main components are as follows:
fig. 3 shows a voltage stabilization chip U3, which is a chip of SPX3819-3.3V type;
fig. 4 a bidirectional transceiver U6, model SN65176BDR bidirectional transceiver;
fig. 5-7 optocoupler E1 fig. 7, optocoupler E2 fig. 5 and optocoupler IC5 fig. 6 employ an optocoupler model EL 357N;
fig. 9 shows that the voltage transformers PT1, PT2 and PT3 are all voltage transformers of the type ZMPT 107;
fig. 12 shows that the single-phase metering chip U1 is an RN8211B type chip;
fig. 14 shows that the three-phase metering chip U2 is a chip of RN8302B type;
to sum up, the utility model discloses an intelligent electric energy meter is the intelligent electric energy meter that comes the development through adopting newest low-power consumption, high performance, high integration degree, the special metering chip of high reliability. This smart electric meter a chip accomplishes measurement, storage, demonstration, communication and pulse function, and the product circuit is simplified, and the reliability improves, and this product can also insert the internet through RS485 circuit and outside equipment simultaneously, realizes remote management and control function, possesses forward and reverse current measurement function simultaneously. Meanwhile, the technical design of the electric energy meter adopts a modular design, and the metering product for metering the large current in three phases is realized by matching different signal boards through a common power supply board. The utility model discloses can develop different types of electric energy meter fast, can make the positive and negative measurement of three-phase intelligent electric energy meter realization electric energy, realize buying and selling the electricity with the meter measurement, reduce use cost, also can realize the network remote management ammeter through the network equipment who takes RS 485's interface to join in marriage simultaneously, reduce the on-the-spot maintenance cost.
The above only is the preferred embodiment of the present invention, not limiting the scope of the present invention, all the equivalent structures or equivalent flow changes made by the contents of the specification and the drawings, or directly or indirectly applied to other related technical fields, are included in the same way in the protection scope of the present invention.

Claims (6)

1. The utility model provides a novel multi-functional intelligent ammeter of three-phase, including power strip (1), with signal board (2) that power strip (1) electricity is connected and with voltage transformer (3) that signal board (2) electricity is connected, its characterized in that:
the power panel (1) is connected with a power chip T1 and a transformer T2 in a circuit, the output of converting 220V alternating current into 4.5V is realized through the power chip T1 and the transformer T2, the output end of 4.5V is electrically connected with a voltage stabilizing chip U3, the voltage stabilizing chip U3 is converted into 3.3V voltage output required by the work of a main control IC on the signal panel (2), the 3.3V voltage output end is transmitted to the signal panel (2) through a J1 terminal, the transformer T2 is further provided with a 5V output circuit, the 5V output circuit is transmitted to a bidirectional transceiver U6 on the power panel (1) for supplying power, and the power panel (1) is further provided with an isolation output circuit;
the voltage transformer (3) is arranged on the power panel (1), and a power grid voltage signal is converted into a small current signal through the voltage transformer (3) and is sent to the main control IC through a J3 interface for voltage measurement;
the signal board (2) is a three-phase main control board, and a main control IC for metering signal processing, display output, pulse output and RS485 communication signal output is arranged on the signal board;
the power panel (1) is connected with three-phase power, and three-phase voltage signals of a power grid are converted into small current signals through a voltage transformer PT1, a voltage transformer PT2 and a voltage transformer PT3 and are sent to the master control IC through a J3 interface to be subjected to voltage metering.
2. The novel three-phase multifunctional intelligent electric energy meter according to claim 1, characterized in that: the power panel (1) is further provided with an optical coupler E1, an optical coupler E2 and an optical coupler IC5 which are connected to the 3.3V voltage output end, the bidirectional transceiver U6 is used for converting one path of serial ports of the signal panel (2) into an RS485 circuit, signal isolation transmission is achieved through the optical coupler E1 and the optical coupler E2, and finally pulse signals are isolated and output to the outside through the optical coupler IC 5.
3. The novel three-phase multifunctional intelligent electric energy meter according to claim 1, characterized in that: the signal board (2) comprises a three-phase signal board connected into a three-phase power supply board.
4. The novel three-phase multifunctional intelligent electric energy meter according to claim 3, characterized in that: in the three-phase signal board, main control IC on it includes three-phase measurement chip U2 and single-phase measurement chip U1, and the power passes through the J2 interface and follows the three-phase signal board is sent into in power strip (1), and the electric current after the three-phase voltage conversion passes through the J3 interface and reaches the three-phase signal board, and three-phase electric current passes through voltage transformer PT1 respectively, voltage transformer PT2, voltage transformer PT3 back respectively through VA1, VB1, three-phase measurement chip U2 on the three-phase signal board of VC1 access, and three-phase measurement chip U2 carries out data transmission through SPI interface and single-phase measurement chip U1.
5. The novel three-phase multifunctional intelligent electric energy meter according to claim 4, characterized in that: when the single-phase metering chip U1 and the three-phase metering chip U2 are used in a matching mode, the single-phase metering chip U1 only serves as display and serial port communication.
6. The novel three-phase multifunctional intelligent electric energy meter according to claim 5, characterized in that: the three-phase signal board is provided with an LCD display screen JH1, the LCD display screen JH1 is used for displaying the numerical values of current, voltage, power, electric energy and frequency measured by the electric energy meter, a 26-pin CF1 of the three-phase metering chip U2 is in pulse output, and the LED2 is a power indicator lamp.
CN201922092678.8U 2019-11-28 2019-11-28 Novel three-phase multifunctional intelligent electric energy meter Active CN211293068U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201922092678.8U CN211293068U (en) 2019-11-28 2019-11-28 Novel three-phase multifunctional intelligent electric energy meter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201922092678.8U CN211293068U (en) 2019-11-28 2019-11-28 Novel three-phase multifunctional intelligent electric energy meter

Publications (1)

Publication Number Publication Date
CN211293068U true CN211293068U (en) 2020-08-18

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