CN201845054U - Multifunctional digital phase detection measuring instrument - Google Patents
Multifunctional digital phase detection measuring instrument Download PDFInfo
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- CN201845054U CN201845054U CN2010205292268U CN201020529226U CN201845054U CN 201845054 U CN201845054 U CN 201845054U CN 2010205292268 U CN2010205292268 U CN 2010205292268U CN 201020529226 U CN201020529226 U CN 201020529226U CN 201845054 U CN201845054 U CN 201845054U
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Abstract
The utility model relates to a multifunctional digital phase detection measuring instrument, which belongs to the technical field of electrical measurement and control for machine tools and mainly solves the problem that phase sequence identification, phase measurement and amplitude measurement can be realized only with different devices presently. The multifunctional digital phase detection measuring instrument is mainly characterized by comprising a micro processing unit portion, a detection circuit portion, an analog-digital conversion circuit portion, a phase sequence output circuit portion and a display output portion, wherein the detection circuit portion comprises three voltage transformers and three current transformers corresponding to three-phase power, the analog-digital conversion circuit portion comprises an eight-way analog switch and an analog-digital converter, and the phase sequence output circuit portion comprises a tristate gate driving circuit and a phase sequence conversion circuit. The multifunctional digital phase detection measuring instrument is simple in integrated circuit design, high in integration and novel in measurement method, is capable of monitoring and controlling the circuit in real time, and is mainly used for detection and measurement of phase sequence, phase, voltage and current of industrial 50Hz three-phase alternating-current circuits, and control of conduction angles of silicon controlled thyristors.
Description
Technical field
The utility model belongs to Machine Tools Electric and measures and the control technology field; a kind of multifunctional digital phase-detecting measuring instrument of main proposition; it is core with the microprocessor technology; the utilization voltage transformer (VT); current transformer; the integrated circuit that multiway analog switch and analog to digital converter are formed; be aided with professional application software; realize the phase sequence identification of industrial three-phase 50Hz alternating current; phase measurement; voltage and current value are measured in real time; single-phase overvoltage; under-voltage; phase shortage; overcurrent; short-circuit condition digital control; to replace the conventional phase metering circuit; the electric scheme that voltage and current measurement circuit separate; realize phase measuring circuit and voltage by easy circuit design; current amplitude is measured the unification with holding circuit, reaches the multi-functional use of instrument.
Background technology
At present, the electric scheme that known industrial three-phase electricity measuring equipment generally adopts phase sequence identification circuit, phase measuring circuit, amplitude measurement circuit to separate, wherein phase measuring circuit adopts analogy method such as phase differential pulse integration circuit, or adopt numerical approach such as phase differential pulse-scaling circuit to realize, and amplitude measurement often adopts simulation rectification or digital circuit to realize, but mainly there is following shortcoming in above-mentioned metering circuit: 1) not with phase sequence identification, phase place and amplitude measurement circuit organic unity; 2) integrated circuit (IC) design relative complex; 3) amplitude measurement has power attenuation; 4) existing equipments resources is fully used.Therefore how with microprocessor as control system, the simplicity of design integrated circuit overcomes above-mentioned shortcoming, has both made the unified realization of phase sequence, phase place and amplitude measurement circuit, can realize the Digital Detecting of single-phase overvoltage, under-voltage, phase shortage, overcurrent, short-circuit condition again, be starting point of the present utility model.
Summary of the invention
The purpose of this utility model promptly is to propose a kind of multifunctional digital phase-detecting measuring instrument, it with microprocessor as control system, join with common voltage transformer (VT), current transformer, multiway analog switch and analog to digital converter, realize the integrated of phase place, voltage and current amplitude metering circuit, and realize the Digital Detecting of single-phase overvoltage, under-voltage, phase shortage, overcurrent, short-circuit condition.
Technical solution of the present utility model is: a kind of multifunctional digital phase-detecting measuring instrument, mainly comprise microprocessor portion, testing circuit part, analog to digital conversion circuit part, phase sequence output circuit part, display output circuit part, and schematic diagram is as shown in Figure 1.Wherein:
A, microprocessor portion are made of a slice microprocessor, microprocessor sends control signal selection, conversion definite, the reading of transformation result constantly of analog-digital converter circuit input signal is controlled, handle the analog to digital conversion result based on the program of phase measurement inside, draws phase sequence, phase place and voltage and the electric current instantaneous value of three-phase circuit;
B, testing circuit portion are made up of three voltage transformer (VT) and three current transformers corresponding with three-phase electricity respectively, these three voltage transformer (VT) link to each other with the input end of multiway analog switch respectively with three current transformers, testing circuit part is carried out no-load voltage ratio to three-phase electricity and is handled, and makes the simulating signal of acquisition meet the analog input scope of analog to digital converter;
C, the analog to digital conversion circuit part is made of one 8 path analoging switch and an analog to digital converter, 8 path analoging switch receive 6 tunnel simulating signals of self-detection circuit, the output terminal of analog switch links to each other with the input end of analog to digital converter, the output terminal of analog to digital converter is connected with the P0 mouth of microprocessor, the control signal of analog to digital conversion circuit is sent by microprocessor P0 mouth, the P0 mouth connects a ternary latch again, the output of latch connects the control end of 8 path analoging switch and analog to digital converter respectively, 8 path analoging switch are selected each road analog input by the requirement of microprocessor, analog to digital converter with the analog input conversion digital signal, and transmits 12 bit data to microprocessor according to the requirement of control signal by the requirement of microprocessor;
D, phase sequence output circuit part, are sent signal and are adjusted the three-phase circuit phase sequence according to the result that the microprocessor internal program is analyzed by triple gate driving circuit and phase sequence reset coil;
E, display output circuit part are made of display driver circuit and display, and display driver circuit is connected with the P0 mouth of microprocessor portion, according to the result of process analysis, by the data of P0 mouth, show the current state of three-phase electricity.Because display output circuit does not belong to core content of the present utility model,, in basic circuit diagram of the present utility model, do not give demonstration so adopt general LED display circuit to get final product yet.
Can also comprise outside input circuit part in the technical solution of the present utility model, be mainly used to handle the external key input.
Can also comprise the communication interface part in the technical solution of the present utility model, this communication interface part connects universal serial bus by microprocessor, carries out exchanges data with external host and constitutes, and interface circuit is finished the communication with host computer equipment.
The utility model as control system, is formed testing circuit with common voltage transformer (VT), current transformer with microprocessor, and it is selected the input of back as analog to digital converter by 8 path analoging switch; Analog to digital converter carries out digital conversion and sampling to the detection signal of three-phase electricity, transfers to microprocessor program again and carries out phase calculation and compensation analysis, thereby determine phase sequence, the phase place of three-phase electricity; According to phase measurement voltage, electric current are measured in real time again, load-carrying three-phase circuit is carried out the Digital Detecting of single-phase overvoltage, under-voltage, phase shortage, overcurrent, short circuit.
The multifunctional digital phase-detecting measuring instrument that the utility model proposes, the integrated circuit hardware design is simple relatively, is easy to integratedly, and software is based on the design of phase measurement and backoff algorithm, so the measuring accuracy height, carries out the efficient height; Have the in good time measuring ability of circuit various states, can in time send information, the holding circuit load; Have RS-232, RS-485 standard communication interface, be beneficial to the robotization that realizes field control, integrated.Because this multifunctional digital phase-detecting measuring instrument adopts easy integrated circuit (IC) design, be aided with software analysis, remedy the part shortcoming of hardware, can give full play to the effect of hardware with software, reaching the purpose of multi-functional accurate measurement, thereby has important use value.
The utility model is mainly used in the measurement of three-phase circuit phase sequence, phase place, voltage and current value, the control of thyristor operating angle.
Description of drawings
Fig. 1 is circuit theory diagrams of the present utility model.
Fig. 2 is the conversion synoptic diagram of the utility model analog to digital converter.
Fig. 3 is the theory diagram that carries out routine processes in the utility model microprocessor.
Embodiment
In conjunction with the accompanying drawings the utility model embodiment is illustrated.
Circuit theory diagrams of the present utility model as shown in Figure 1.The utility model mainly partly is made up of microprocessor portion, testing circuit part, analog to digital conversion circuit part, phase sequence output circuit part, display output circuit part, outside input circuit part and communication interface.Microprocessor portion is made of the 89C52 microprocessor.The analog to digital conversion circuit part is made of one 8 path analoging switch and an A/D converter.The testing circuit part is made up of three voltage transformer (VT) TV1, the TV2 corresponding with three-phase electricity, TV3 and three current transformer TA1, TA2, TA3, these three voltage transformer (VT) TV1, TV2, TV3 are connected with the corresponding input end of 8 path analoging switch through resistance R 1, R2, R3 respectively, and three current transformer TA1, TA2, TA3 are connected with the input end of 8 path analoging switch respectively; The output terminal of 8 path analoging switch links to each other with the input end of A/D converter.The phase sequence output circuit part is made of triple gate driving circuit and phase sequence reset coil KM1, KM2.The display output circuit part is made of display driver circuit and display, and display driver circuit is connected with the P0 mouth of microprocessor portion.Because display output circuit does not belong to core content of the present utility model,, in basic circuit diagram of the present utility model, do not give demonstration so adopt general LED display circuit to get final product yet.The communication interface part connects universal serial bus by microprocessor P3.2 mouth by interrupt mode, carries out exchanges data with external host and constitutes.Outside input circuit part is made of by interrupt mode microprocessor P3.3 mouth.
The course of work that the utility model proposes to detect and measure is: after powering up, microprocessor at first carries out self check; Then analog to digital conversion circuit is sent control signal, select 6 tunnel analog inputs to carry out analog to digital conversion successively, after finishing, by the microprocessor internal program data of sampling in the voltage cycle being carried out phase analysis calculates with compensation, determine the phase sequence and the phase place of three-phase electricity, the method of taking single-phase peak value sampling to be equipped with the special angle sampling is then measured the real-time voltage value and the current value of three-phase electricity, whether analysis circuit operation exists the situation of single-phase overvoltage, under-voltage, phase shortage, overcurrent, short circuit, if any then reporting to the police.
Core circuit major function of the present utility model is as follows: microprocessor is the core of native system hardware, intends adopting 89C52, and power frequency is 12MHz, and its built-in 8K flash memory need not add external memory.The P0 mouth of microprocessor is as analog to digital conversion result's the mouth that reads, and the delivery outlet of display device data also is a multichannel analog to digital converter and analog switch control mouth; The analog to digital conversion circuit control signal of microprocessor output is also sent by the P0 mouth, and earlier by the 74LS373 latch, low four are selected end as the analog to digital converter sheet respectively
, most-significant byte and low 4 selecting side A, change and read the selecting side
, 12 or 8 output terminals
Control signal, Gao Siwei is as three selecting side A0, A1, A2 and an Enable Pin of multiway analog switch
Control signal, in order to gating 6 road analog input signals; The P2.0 of microprocessor, P2.1 are the control bit of phase sequence reset coil KM1 and KM2, by triple gate output, and the Enable Pin of P2.2 control triple gate; The STS end of P2.3 connection mode number converter determines with the mode of inquiry whether analog to digital conversion finishes; The P2.4-P2.7 mouth, the P1 mouth keeps; P3.0, P3.1 are as the CE end of read-write control end control analog to digital converter; Inner T1 and T2 use as program timer respectively.The professional software part of microprocessor is carried out unified management to system hardware, and analog-digital conversion data is analyzed.Testing circuit is made up of three voltage transformer (VT) TV1, TV2, TV3 and three current transformer TA1, TA2, TA3, wherein be connected a resistance is respectively arranged on the voltage transformer (VT), to play threshold currents, 6 tunnel simulating signals are by 8 path analoging switch CC4051, select wherein one road input port that is connected to analog to digital converter; Select current transformer, the voltage transformer (VT) of different no-load voltage ratios for use, can finish measurement different three-phase circuits.Analog to digital conversion circuit is earlier by 8 path analoging switch CC4051, according to the control of high 4 signals of microprocessor P0 mouth, select one tunnel analog quantity as input, AD574 changes by analog to digital converter, numeral output passes to microprocessor on request, does further process analysis and handles; The analog to digital converter of different switching speed draws different phase measurement accuracies, as selects the switching device of middling speed 25 μ s for use, and measuring error is selected the switching device of 2 μ s at a high speed for use less than 0.2 °, and measuring error is less than 0.04 °.
Auxiliary circuit major function of the present utility model is as follows: the phase sequence output circuit is made up of two triple gates and phase sequence reset coil KM1, KM2, be used for exporting the phase sequence result that microprocessor program is analyzed, KM1, KM2 are by the power supply of+24V power supply, by P2.0, P2.1 control, P2.2 is the control signal of two triple gates respectively.Status datas such as voltage, electric current, overvoltage, under-voltage, phase shortage, overcurrent, short circuit send the Universal LED screen to show (not drawing in the drawings) by the output of P0 mouth.The utility model microprocessor 89C52, analog to digital converter AD574, multiway analog switch CC4051 operating voltage are+5V that the AD574 reference voltage is ± 15V that relay coil voltage is+24V.The communication interface circuit is an Interface Terminal.
In the utility model, P3. 2 is a fracture in the serial of RS-232, RS-485 communication interface, can be in good time when making things convenient for it to move as the clump machine and main control computer carry out communication, by host computer, the data with slave that can be real-time focus on.P3.3 interrupts input interface as the serial of external keyboard input.
The conversion synoptic diagram of analog to digital converter as shown in Figure 2.Its principle is to determine the maximal value of amplitude according to transformation result, draws 90 ° of phase place places simultaneously constantly.
The theory diagram that carries out routine processes in the microprocessor as shown in Figure 3, during Measurement Phase, because the existence of circuit inductance, electric capacity, carry out necessary phase compensation, based on this, real-time voltage, current value are calculated, and analyze the situation of single-phase overvoltage, under-voltage, phase shortage, overcurrent, short circuit.
Claims (3)
1. multifunctional digital phase-detecting measuring instrument is characterized in that: mainly comprise microprocessor portion, testing circuit part, analog to digital conversion circuit part, phase sequence output circuit part and display output circuit part, wherein:
A, microprocessor portion are made of microprocessor, sending control signal by microprocessor controls selection, conversion definite, the reading of transformation result constantly of analog to digital converter part input signal, handle the analog to digital conversion result based on the program of phase measurement inside, draws phase sequence, phase place and voltage and the electric current instantaneous value of three-phase circuit;
B, testing circuit part are made up of three voltage transformer (VT) (TV1, TV2, TV3) corresponding with three-phase electricity and three current transformers (TA1, TA2, TA3), these three voltage transformer (VT) (TV1, TV2, TV3) are connected with the corresponding input end of analog to digital conversion circuit part respectively with three current transformers (TA1, TA2, TA3), testing circuit part is carried out no-load voltage ratio to three-phase electricity and is handled, and makes the simulating signal of acquisition meet the analog input scope of analog to digital converter;
C, analog to digital conversion circuit part are made of one 8 path analoging switch and an analog to digital converter, the input end of 8 path analoging switch connects the voltage transformer (VT) summation current transformer corresponding with three-phase electricity, output terminal connection mode number converter, the output terminal of analog to digital converter is connected with the P0 mouth of microprocessor, the control end of 8 path analoging switch and analog to digital converter is connected behind latch by the signal that the P0 mouth sends, requirement by microprocessor is changed each road input, and the good back result of conversion passes to microprocessor;
D, phase sequence output circuit part are made of triple gate driving circuit and phase sequence reset coil (KM1, KM2), according to the result of process analysis, send signal and make driving circuit adjust the three-phase circuit phase sequence;
E, display output circuit part are constituted or are made of the LED display circuit by display driver circuit and display, display driver circuit or LED display circuit are connected with the P0 mouth of microprocessor, according to the result of process analysis,, show the current state of three-phase electricity by the data of P0 mouth.
2. multifunctional digital phase-detecting measuring instrument according to claim 1, it is characterized in that: also comprise the communication interface part, this communication interface part is interrupted 0(P3.2 by microprocessor) mouthful connection universal serial bus, carry out exchanges data with external host and constitute, interface circuit is finished the communication with host computer equipment.
3. multifunctional digital phase-detecting measuring instrument according to claim 1 and 2 is characterized in that: also comprise outside input circuit part, this section processes external keyboard input is interrupted 1 mouthful (P3.3) by microprocessor and is handled by interrupt mode.
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| CN2010205292268U CN201845054U (en) | 2010-09-15 | 2010-09-15 | Multifunctional digital phase detection measuring instrument |
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| CN2010205292268U CN201845054U (en) | 2010-09-15 | 2010-09-15 | Multifunctional digital phase detection measuring instrument |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102324723A (en) * | 2011-09-21 | 2012-01-18 | 山东一统电器有限公司 | Flameproof phase-sensitive short circuit protection feed switch and working method thereof |
| CN102769271A (en) * | 2012-07-09 | 2012-11-07 | 佛山市柏克新能科技股份有限公司 | Output protection circuit for alternating-current power supply |
| CN103592515A (en) * | 2013-11-21 | 2014-02-19 | 厦门安达兴电气集团有限公司 | Universal phase identifier |
| CN104849538A (en) * | 2014-02-14 | 2015-08-19 | 英飞凌科技股份有限公司 | Switching power converter current sensing with phase current estimator |
| CN106597134A (en) * | 2016-12-31 | 2017-04-26 | 国家电网公司 | Intelligent distribution network secondary system phase sequence automatic check apparatus |
| CN115144646A (en) * | 2022-07-14 | 2022-10-04 | 杭州恒芯微电子科技有限公司 | Quick detection unit for voltage overvoltage and current overcurrent |
| CN116582115A (en) * | 2023-06-01 | 2023-08-11 | 上海铅锂冀电子科技有限公司 | Switch on-off control device and circuit for controlling multi-way switch on-off by 5 signal lines |
-
2010
- 2010-09-15 CN CN2010205292268U patent/CN201845054U/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102324723A (en) * | 2011-09-21 | 2012-01-18 | 山东一统电器有限公司 | Flameproof phase-sensitive short circuit protection feed switch and working method thereof |
| CN102324723B (en) * | 2011-09-21 | 2014-04-09 | 山东一统电器有限公司 | Flameproof phase-sensitive short circuit protection feed switch and working method thereof |
| CN102769271A (en) * | 2012-07-09 | 2012-11-07 | 佛山市柏克新能科技股份有限公司 | Output protection circuit for alternating-current power supply |
| CN102769271B (en) * | 2012-07-09 | 2015-08-26 | 佛山市柏克新能科技股份有限公司 | A kind of AC power output protection circuit |
| CN103592515A (en) * | 2013-11-21 | 2014-02-19 | 厦门安达兴电气集团有限公司 | Universal phase identifier |
| CN104849538A (en) * | 2014-02-14 | 2015-08-19 | 英飞凌科技股份有限公司 | Switching power converter current sensing with phase current estimator |
| CN104849538B (en) * | 2014-02-14 | 2018-02-16 | 英飞凌科技股份有限公司 | Phase Current Estimator and Switching Power Converter |
| US9998011B2 (en) | 2014-02-14 | 2018-06-12 | Infineon Technologies Ag | Phase current estimation for switching power converters |
| CN106597134A (en) * | 2016-12-31 | 2017-04-26 | 国家电网公司 | Intelligent distribution network secondary system phase sequence automatic check apparatus |
| CN115144646A (en) * | 2022-07-14 | 2022-10-04 | 杭州恒芯微电子科技有限公司 | Quick detection unit for voltage overvoltage and current overcurrent |
| CN116582115A (en) * | 2023-06-01 | 2023-08-11 | 上海铅锂冀电子科技有限公司 | Switch on-off control device and circuit for controlling multi-way switch on-off by 5 signal lines |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110525 Termination date: 20120915 |