CN202404150U

CN202404150U - Current transducer

Info

Publication number: CN202404150U
Application number: CN201220016189XU
Authority: CN
Inventors: 王禹桥; 胡爱国; 李允彩
Original assignee: XUZHOU SHICHANG ELECTROMECHANICAL TECHNOLOGY CO LTD
Current assignee: XUZHOU ZHONGKUANG TRANSMISSION TRACK TECHNOLOGY CO., LTD.
Priority date: 2012-01-16
Filing date: 2012-01-16
Publication date: 2012-08-29
Anticipated expiration: 2022-01-16

Abstract

The utility model discloses a current transducer, which relates to the technical field of current conversion and comprises an amplification filter circuit, an A/D (analog/digital) conversion circuit, a microprocessor and a frequency output circuit. Sampled voltage signals of a current divider are inputted into the A/D conversion circuit after being amplified by the amplification filter circuit, and are inputted into the microprocessor after being converted into digital signals by the A/D conversion circuit, the digital signals are converted into corresponding PWM (pulse-width modulation) signals to be outputted according to the magnitude of voltage after being processed by the microprocessor, the PWM signals drive the frequency output circuit to work, and frequency is transmitted to an electric drainage cabinet and a controller of a one-way conduction device after driving current is amplified. The current transducer has the advantages of high precision, stability and reliability in work, high interference resistance, economical efficiency and practicality.

Description

Current transducer

Technical field

The utility model relates to the current conversion technical field, specifically is a kind of current transducer, and with the high-precision frequency signal that converts into of current signal, the electrorheological that is specially adapted to current drainage cabinet, Device in one-way on state branch road send.

Background technology

During the work of current drainage cabinet, Device in one-way on state, need monitor the electric current of each branch road, be sent to intelligent controller to the current signal of monitoring, monitor in real time.

Present most current transducer all is to adopt analog device to accomplish, and this type of product structure is complicated, and precision is not high, and anti-interference is poor, complicated circuit.

Summary of the invention

In order to overcome the shortcoming of above-mentioned prior art, the utility model provides a kind of current transducer, and is with the high-precision frequency signal that converts into of current signal, simple and practical, precision is high, antijamming capability is strong.

The utility model is realized with following technical scheme: current transducer, comprise amplification filtering circuit, A/D change-over circuit, microprocessor and frequency output circuit, and the voltage signal of shunt amplifies the back, is input to the A/D change-over circuit voltage signal through the amplification filtering circuit; Voltage signal is input microprocessor after the A/D change-over circuit converts digital quantity to; Through after the microprocessor processes,, convert corresponding PWM output into according to the size of voltage; The work of PWM driving frequency output circuit; Drive current is amplified, be sent to the controller of current drainage cabinet, Device in one-way on state to frequency, realize the transmission of frequency.

The beneficial effect of the utility model: whole device adopts high-precision operational amplifier, A/D conversion chip, microprocessor to carry out Signal Processing; Final through output PWM, convert frequency output into and transmit, anti-interference is good; Precision is high, is convenient to Signal Spacing, long-distance transmissions.

Description of drawings

Fig. 1 is the utility model theory diagram;

Fig. 2 is the circuit theory diagrams of Fig. 1.

Embodiment

As shown in Figure 1, current transducer has the amplification filtering circuit, A/D change-over circuit, microprocessor and frequency output circuit.Through gathering the voltage of shunt on current drainage cabinet, the individual event conducting device branch road; The voltage signal of gathering amplifies the back, is input to the A/D change-over circuit voltage signal through the amplification filtering circuit, and voltage signal is input microprocessor after the A/D change-over circuit converts digital quantity to, through after the microprocessor processes; Size according to voltage; Convert corresponding PWM output into, the work of PWM driving frequency output circuit is amplified drive current; Be sent to the controller of current drainage cabinet, Device in one-way on state to frequency, realize the transmission of frequency.

As shown in Figure 2, the amplification filtering circuit adopts operational amplifier A D620.The A/D change-over circuit adopts A/D conversion chip TLC2543; This chip is 12 bit serial analog to digital converters, uses switching capacity approximation technique completion A/D transfer process one by one, and resolution is high, and slewing rate is fast.Microprocessor adopts the STC12C5410AD chip, and this chip is a new generation's 8051 single-chip microcomputers of high speed/low-power consumption, brand-new streamline/reduced instruction structure set, required unit module in having comprised data acquisition and having controlled..The frequency output circuit adopts triode, and pwm signal drives triode work, and electric current is amplified, and realizes that the change of electric current is sent.

Signal Vin0 that gathers and Vin1 are through resistance R 16, R17, R20, R21; R41, the resistor network that R43 forms can be regulated resistance value and mate various input voltage and input current signals, through capacitor C 3; After C4 carried out filtering, 2,3 pins of arithmetical unit AD620 were amplified in input; From 6 pin connecting resistance R23, R24, the filter circuit output Vout that C7 forms.1,8 pin of AD620 is through resistance R 22 series connection, and pin 4 connects-5V, capacitor C 5, electrochemical capacitor CE7 ground connection, and pin 5 ground connection, pin 7 meets VCC, and through capacitor C 6, electrochemical capacitor CE8 ground connection is eliminated ground and is disturbed.

The AD conversion chip adopts TLC2543, and the signal Vout after amplifying through AD620 is input to the pin 1 of TLC2543, after the analog quantity input transforms through AD; From pin 16 SOD serial output datas, pin 16 connects the pin 21 of STC12C5410AD, pin 15; Pin 17, pin 18, pin 19 connect the pin 22 of STC12C5410AD respectively; Pin 20, pin 19, pin 18.Pin 10 ground connection, pin 20 meets VCC, pin 13 ground connection; Pin 14 connects the adjustable pin of adjustable resistance RE1, two pins, the one end ground connection that RE1 is other, and the other end meets VCC through resistance R 26; The adjustable pin of RE1 connects capacitor C 29 ground connection; Capacitor C 23 is parallelly connected with adjustable resistance RE1, and the pin 2,3 of reference source LM336 connects the two ends of adjustable resistance respectively.Obtain stable reference voltage through regulating adjustable resistance.

Microprocessor 3 adopts the STC12C5410AD chip, and the pin 15 of the pin 22 control TLC2543 of microprocessor (chip selection signal/CS), when micro processor leg 22 is high level; Input and output clock end pin 18 and the data input pin pin 17 of TLC2543 are under an embargo; Data output end pin 16 is a high-impedance state, and when micro processor leg 22 became low level, the TLC2543 data began conversion; TLC2543 pin 18 is effective with pin 17; And pin 16 breaks away from high-impedance states, and the eoc signal of pin 19 outputs of TLC2543 is used for representing being connected beginning and the end changed with the pin 18 of microprocessor.

Microprocessor 3 is through pin 21 simulation SPI data output SPIDatain; Pin 20 simulation SPI data input port SPIDataout; Pin 19 simulation SPI clock end.Microprocessor 3 pins 20 output 4 analog channel addresses (D7 one D4), 2 bit data length select (D3～D2), one select output MSB or LSB in preceding position (D1) and unipolarity or bipolarity output select the pin 17 of 8 bit data of position (DO) to TLC2543.Microprocessor 3 pins 19 clock signals, under the I/O clock control, microprocessor 3 pins 20 transmit the pin 17 of control word to TLC2543, and the preceding once result of conversion of TLC2543 delivers to pin 16 simultaneously.Pin 16 transmits the pin 21 that data are given microprocessor 3 through the mode of serial output, and microprocessor 3 is stored data.

Microprocessor 3 obtains the data after the AD conversion, to register, after computing, exports corresponding PWM to data storage from pin 17.

1,2,4,5,8,9,10,11,12,13 connect respectively and draw resistance R 4, R5, R33,, R34, R35, R36, R37, R38, R39, R40 to VCC.Pin 3 connects reset circuit, and reset circuit meets electrochemical capacitor CE1 to VCC, meets diode D1, and the circuit of resistance R 1 capacitor C 9 parallel connections is to ground.Pin 4,5 is the program download interface, connects the

3,4 of downloading mouthful L1 respectively, and the pin 1 of L1 meets VCC, pin 2

ground connection.Pin

1,2,8,9,10,11,12,13 for reserving

IO port.Pin

3,4 connects by capacitor C 1, C2, the crystal oscillating circuit that crystal oscillator Y1 forms.

After the computing through microprocessor, from the corresponding PWM of pin 17 output, pin 17 connects the base stage of triode 9013 through resistance R 25, and base stage is connected through C18 with emitter; Pin 17 is connected through capacitor C 28 with emitter, and collector connects 1 end of connection terminal L2, the 2 terminating resistor R3 to VCC of L2; When pin 17 output pwm signals, drive triode work, electric current is amplified; Thereby the pin of L1 1,2 output frequency signal has realized that the change of electric current is sent.

Claims

1. current transducer is characterized in that: comprise amplification filtering circuit, A/D change-over circuit, microprocessor and frequency output circuit, the voltage signal of shunt amplifies the back, is input to the A/D change-over circuit voltage signal through the amplification filtering circuit; Voltage signal is input microprocessor after the A/D change-over circuit converts digital quantity to; Through after the microprocessor processes,, convert corresponding PWM output into according to the size of voltage; The work of PWM driving frequency output circuit; Drive current is amplified, be sent to the controller of current drainage cabinet, Device in one-way on state to frequency, realize the transmission of frequency.

2. current transducer according to claim 1 is characterized in that: described amplification filtering circuit adopts operational amplifier A D620; Described A/D change-over circuit adopts A/D conversion chip TLC2543; Described microprocessor adopts the STC12C5410AD chip.