CN103383410A

CN103383410A - Multifunctional power meter

Info

Publication number: CN103383410A
Application number: CN2013102766167A
Authority: CN
Inventors: 刘维东
Original assignee: CHONGQING YUETENG ELECTRICAL APPLIANCE Co Ltd
Current assignee: CHONGQING YUETENG ELECTRICAL APPLIANCE Co Ltd
Priority date: 2013-07-02
Filing date: 2013-07-02
Publication date: 2013-11-06

Abstract

The invention relates to the field of power meters and aims at disclosing a multifunctional power meter. The multifunctional power meter comprises a microprogrammed control unit (MCU) module and a power module. The MCU module is connected with a current collection module, a voltage collection module, a data display module and a data communication module. The MCU module comprises a 71M6534H chip connected with an FM25640 chip and serving as a data storage. The current collection module comprises a current transformer connected with three phases respectively through induction, a current signal collected by the current transformer passes through a filtering capacitor and a differential sampling circuit to form a differential current signal, and the current transformer is connected into pins (99-104) of the 71M6534H chip correspondingly. The three-phase voltage input end obtains a voltage signal through a voltage dividing resistor and the filtering capacitor and is connected into pins (93-95) of the 71M6534H chip correspondingly. The power meter is reliable in design, high in accuracy, complete in function and capable of replacing conventional power transmitters, measurement indicators, power measuring instruments and relevant auxiliary units.

Description

Multifunctional electric meter

Technical field

The present invention relates to the electric instrument field, refer to especially a kind of multifunctional electric meter.

Background technology

In the electric instrument industry, the induction type electric energy meter that falls behind is progressively eliminated by electronic electric energy meter.The electronic type multifunctional meter of comparative maturity has been widely used in electric system in the market, and along with the development of power industry and improving constantly of market demands, watt-hour meter need to be to high precision, intellectuality, multi-functional future development.For the application scenario of the power monitorings such as electric system, industrial and mining enterprises, intelligent building, Based Intelligent Control, metering examination, the multifunctional electric meter of high performance-price ratio, high precision, high reliability replaces conventional electric power transmitter, measurement indicating instrument, electric energy measurement instrument becomes must.

Summary of the invention

The present invention proposes a kind of multifunctional electric meter, its reliable design, and precision is high, and is multiple functional, can replace the conventional electric power transmitter, measure indicating instrument, electric energy measurement instrument and relevant auxiliary unit.

technical scheme of the present invention is achieved in that a kind of multifunctional electric meter, comprise MCU module 1 and power module 4, described MCU module 1 is connected with current acquisition module 5, voltage acquisition module 6, data disaply moudle 7 and data communication module 8, described MCU module 1 comprises the 71M6534H chip, described 71M6534H chip is connected with the FM25640 chip as data storage, described current acquisition module 5 comprises with three-phase electricity responds to respectively the current transformer that is connected, the current signal that described current transformer collects obtains the pin 99～104 of the corresponding access of differential current signal 71M6534H chip through filter capacitor and difference sample circuit, described three-phase electricity voltage input end obtains the pin 93～95 of the corresponding access of voltage signal 71M6534H chip through divider resistance and filter capacitor.

Described 71M6534H integrated chip electric energy metrical and managing in one, reliable operation, superior performance, with low cost, functional module is abundant, it is as the core of electric energy meter, and it comprises compatible 8051MPU kernel, high precision RTC and the lcd driver of a 10MHz, and compatibility is convenient to be applied to well various control system.This chip also has been equipped with the A/D converter of 22, it can directly accept the input of three-phase voltage and difference current, embedded digital temperature compensation module, accurate reference voltage and 32 computing engines, therefore only need the only a few external component can apply to electric energy metrical, its measuring accuracy is high, and peripheral circuit is simple, has greatly improved the reliability of system.The FM25640 chip belongs to long-life ferroelectric type storer, has guaranteed the reliability of electric energy meter.

MCU module 1 is by connecting current acquisition module 5, voltage acquisition module 6, but meter is calculated all electrical parameters in electrical network, can complete the metering of voltage in electrical network, electric current, active power, reactive power, power factor (PF), electric energy metrical, frequency and four-quadrant electric energy.

Data disaply moudle 7 can intuitively show each electrical parameter, by data communication module 8 and extraneous handheld device, measurement programming and the digital communication of realization to electric energy meter, field-programmable arranges test parameter, make install more convenient, wiring is simpler, thereby reduce quantities and maintenance, give to use and manage to bring great convenience.

Description of drawings

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, the below will do to introduce simply to the accompanying drawing of required use in embodiment or description of the Prior Art, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the system module figure of a kind of multifunctional electric meter of the present invention;

Fig. 2 and Fig. 3 are the peripheral connection layout of MCU module in Fig. 1;

Fig. 4 is the circuit structure diagram of current acquisition module in Fig. 1;

Fig. 5 is the circuit structure diagram of voltage acquisition module in Fig. 1;

Fig. 6 is the circuit structure diagram of data disaply moudle in Fig. 1;

Fig. 7 is the circuit structure diagram of data communication module in Fig. 1.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Based on the embodiment in the present invention, those of ordinary skills belong to the scope of protection of the invention not making the every other embodiment that obtains under the creative work prerequisite.

a kind of multifunctional electric meter, as shown in Figure 1, comprise MCU module 1 and power module 4, described MCU module 1 is connected with current acquisition module 5, voltage acquisition module 6, data disaply moudle 7 and data communication module 8, described MCU module 1 comprises the 71M6534H chip, described 71M6534H chip is connected with the FM25640 chip as data storage, described current acquisition module 5 comprises with three-phase electricity responds to respectively the current transformer that is connected, the current signal that described current transformer collects obtains the pin 99～104 of the corresponding access of differential current signal 71M6534H chip through filter capacitor and difference sample circuit, described three-phase electricity voltage input end obtains the pin 93～95 of the corresponding access of voltage signal 71M6534H chip through divider resistance and filter capacitor.

MCU module 1 is by connecting current acquisition module 5, voltage acquisition module 6, but meter is calculated all electrical parameters in electrical network, can complete the metering of voltage in electrical network, electric current, active power, reactive power, power factor (PF), electric energy metrical, frequency and four-quadrant electric energy.Data disaply moudle 7 can intuitively show each electrical parameter, by data communication module 8 and extraneous handheld device, measurement programming and the digital communication of realization to electric energy meter, field-programmable arranges test parameter, make install more convenient, wiring is simpler, thereby reduce quantities and maintenance, give to use and manage to bring great convenience.

Being designed to three-phase voltage through rectification after transformer pressure-reducing, filtering, voltage stabilizing of power module 4 guarantees the reliable and stable work of electric energy meter again to system power supply, specifically press industry technology design and gets final product.The periphery design of this MCU module 1 as shown in Figures 2 and 3, the pin 8 of 71M6534H chip meets power supply source+3.3V, and by capacitor C 13, C14 ground connection; Pin one 0 also meets power supply source 3.3V; Pin 65 is by resistance R 38 ground connection; Pin 77～80 is corresponding one by one to be connected with the

5,2,1,6 of FM25640 chip; Pin 83 meets power supply source 3.3V by diode D2; The D2 negative pole is by capacitor C 17 ground connection; Also be connected to the 3.3V power supply source between pin 83 and ground; Pin 85 connects+3.3V power supply source and by resistance R 17 and diode D1 ground connection by capacitor C 16; Pin one 11 is by capacitor C 3, inductance L 3 ground connection; Pin one 13 is by capacitor C 4, inductance L 3 ground connection; Pin one 11 and 113 are connected with crystal resonator Y1.

Fig. 4 and Fig. 5 are the circuit of current acquisition module 5 and voltage acquisition module 6, and wherein LA1, LB1, LC1 are current transformer, and through difference channel, LAP, LAN, LBP, LBN, LCP, LCN are current difference signal.UA, UB, UC are external input voltage, through electric resistance partial pressure, and output voltage single-ended signal VA, VB, VC.Current difference signal and voltage single-ended signal are directly inputted the MCU chip internal and are carried out signals collecting.Voltage signal input Converter Without Voltage Sensor, directly electric resistance partial pressure obtains required signal, has simplified circuit, has alleviated weight and volume, has saved the gauge internal space, has reduced simultaneously internal calorific power.This module resistance adopts the precision resistance of low-temperature coefficient, and it has improved measuring accuracy, has solved the nonlinear problem of sensor and the precision problem that temperature variation causes.

Described data disaply moudle 7 measures at times for the LCD/LED split screen shows three-phase current, three-phase voltage, frequency, power factor, active power, reactive power, applied power, active energy metering, reactive energy measurement, total electric energy metrical, switching value input state, switching value output state, multiple rate electric energy.This module comprises that model is the LED driver of TM1640, and described LED driver is connected with the digital display tube that model is SR420401, also is connected be used to the light emitting diode that coordinates the auxiliary indication of digital display tube between described LED driver and digital display tube.Concrete circuit design can be as shown in Figure 6, and Presentation Function divides charactron and liquid crystal type to show, is shown as example with charactron here, and 3*4 position charactron forms data display area, and single light emitting diode forms auxiliary pilot lamp and coordinates charactron to complete the demonstration of data.The pin two 7～28 of 71M6534H chip and the corresponding connection of the pin 7～8 of TM1640 chip are used for controlling the operation of data disaply moudle 7.Display driving part has used integrated LED driver, substantially there is no what peripheral cell, and the inner constant-current driving LED that adopts has reduced the power consumption that traditional resistance in series current limliting produces, and maximize and simplified circuit, thereby reduced failure rate.

Described data communication module 8 adopts RS485 communication protocol, as shown in Figure 7, comprise that model is the bi-directional transceiver of SN75176B and the triode that is used for switching reiving/transmitting state, this triode is connected with TX with the read-write end RX of 71M6534H chip by connecting optocoupler, the collector of this triode receives pin two and the pin 3 of hair device SN75176B, and the pin 6 of transceiver SN75176B, pin 7 connect by the TVS pipe seedbed that powers.Physical circuit figure can be as shown in Figure 7, and RX is the receiving end of MCU side; TX is the transmitting terminal of MCU side; A, B are the RS485 communication interface.By triode Q1 automatic switchover reiving/transmitting state, lack than traditional RS485 circuit switching traditional circuit of having used an optocoupler to complete transmitting-receiving and also will delay time after switching and could send out data, improved the utilization factor of communication.The RS485 communication function realizes all remote data monitoring, and can long-rangely complete the setting of instrument parameter.Provide the asynchronous serial half-duplex RS 458 communication interfaces, adopt the MOD-BUS-RTU agreement, various data note breaths all can transmit on communication line.Can connect simultaneously a plurality of electric instruments on a circuit, each electric instrument all can be set its address; Realize all remote data monitoring with this, and can each instrumentation of operated from a distance.

Switching value module 2 can adopt optocoupler to realize Isolation input; Switching value output module 3 adopts MCU signal control relay isolation output switch amount signal.Pin one 9～22 correspondences of 71M6534H chip connect the load button on the dynamometer instrument interface, are used for checking reading information.The input of switching value is by the pin 35～37 of the corresponding 71M6534H chip of relay, pin 46～51 and the pin 52 of the corresponding 71M6534H chip of relay passed through in switching value output, the inner pin 38,39 and 41 by the corresponding 71M6534H chip of transmitter output signal of dynamometer instrument.The 71M6534H chip can need to arrange with reference to industry technology and design with being connected of other peripheral circuits, repeated no more here.

The above is only preferred embodiment of the present invention, and is in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, is equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims

1. multifunctional electric meter, comprise MCU module (1) and power module (4), described MCU module (1) is connected with current acquisition module (5), voltage acquisition module (6), data disaply moudle (7) and data communication module (8), it is characterized in that: described MCU module (1) comprises the 71M6534H chip, described 71M6534H chip is connected with the FM25640 chip as data storage, described current acquisition module (5) comprises with three-phase electricity responds to respectively the current transformer that is connected, the current signal that described current transformer collects obtains the pin 99～104 of the corresponding access of differential current signal 71M6534H chip through filter capacitor and difference sample circuit, described three-phase electricity voltage input end obtains the pin 93～95 of the corresponding access of voltage signal 71M6534H chip through divider resistance and filter capacitor.

2. multifunctional electric meter according to claim 1, it is characterized in that: described data disaply moudle (7) comprises that model is the LED driver of TM1640, described LED driver is connected with the digital display tube that model is SR420401, also is connected be used to the light emitting diode that coordinates the auxiliary indication of digital display tube between described LED driver and digital display tube.

3. multifunctional electric meter according to claim 1, it is characterized in that: described data communication module (8) adopts RS485 communication protocol, comprise that model is the bi-directional transceiver of SN75176B and the triode that is used for switching reiving/transmitting state, this triode is connected with TX with the read-write end RX of 71M6534H chip by connecting optocoupler, the collector of this triode receives pin two and the pin 3 of hair device SN75176B, and the pin 6 of transceiver SN75176B, pin 7 connect by the TVS pipe seedbed that powers.

4. multifunctional electric meter according to claim 1, it is characterized in that: described MCU module (1) is connected with switching value module (2) and switching value output module (3).