CN2085972U

CN2085972U - Phase-interruption time-meter for three-phase electric meter

Info

Publication number: CN2085972U
Application number: CN 91215029
Authority: CN
Inventors: 刘运中
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-01-15
Filing date: 1991-01-15
Publication date: 1991-10-02

Abstract

The utility model relates to a lacking phase timekeeping instrument for a three-phase watt-hour meter, which is a monitoring instrument for judging the correctness of the electricity measurement of the three-phase watt-hour meter. The utility model is composed of a lacking phase detector, a clock circuit, a time pulse control circuit, a lacking phase timer and a working power supply, wherein, the lacking phase monitor is composed of an NOT-AND gate circuit and an OR gate circuit. The circuit of the utility model is simple, and the adjustment of the circuit is convenient. The utility model can be widely used for an electric service department, and under the condition of lacking phase measurement, the utility model can monitor lacking phase time so as to ensure the accurate electricity measurement.

Description

Phase-interruption time-meter for three-phase electric meter

The utility model relates to a kind of three phase watt-hour meter phase shortage calculagraph, is a kind of monitor of three phase watt-hour meter metering electricity consumption correctness.

When three phase watt-hour meter measures the user power utilization amount at present, cause a phase or a heterogeneous phase shortage for various reasons, thereby cause watt-hour meter institute quantity calculation to leak meter or disregard, owing to do not know when begin phase shortage, the Lou electricity charge of meter can't correctly be remedied by electric industry department, make and are subjected to very big loss on the national economy.

The purpose of this utility model provides a kind of single-phase phase shortage or heterogeneous non-full-phase state can write down the three phase watt-hour meter phase shortage calculagraph of phase shortage time automatically with correct metering power consumption down.

The technical solution of the utility model adopts to be made up of phase loss detector, clock circuit, time pulse control circuit, phase shortage timer and working power, forms a phase loss detector, three-phase U by Sheffer stroke gate, OR circuit _A, U _B, U _CSignal through resistance, voltage stabilizing diode dividing potential drop, voltage stabilizing after the phase shortage logic distinguishing circuit that Sheffer stroke gate or door are formed obtains two control signal P ₁And P ₂Control two time pulse control circuits respectively, the time pulse that the control clock circuit produces is counted single-phase and heterogeneous phase shortage timer, to add up the time of single-phase and heterogeneous phase shortage respectively.

The utility model embodiment is described in detail in conjunction with the accompanying drawings.

Fig. 1 is a three phase watt-hour meter phase shortage calculagraph block scheme,

Fig. 2 is a three phase watt-hour meter phase shortage calculagraph schematic circuit;

Fig. 3 is three phasor diagrams;

Fig. 4 is for lacking A phase time polar plot.

By shown in Figure 1, three phase watt-hour meter phase shortage calculagraph is by phase loss detector 1, clock circuit 2, time pulse control circuit 3, phase shortage timer 4 and working power 5 are formed, form by Sheffer stroke gate, OR circuit by phase loss detector shown in Figure 2,3 square waves that are mutually 120 ° of three-phase Ua, Ub, Uc that input dropping resistor Ra, Rb, Rc are connected with corresponding stabistor Da, Db, Dc take a sample output terminal with or a H input end be connected, and respectively with corresponding Sheffer stroke gate YFa, YFb; YFb, YFc; YFc, YFa are connected, and the anode of voltage stabilizing diode Da, Db, Dc links together and is connected with unsteady mid point Uo, Sheffer stroke gate YFa, YFb, YFc output and Sheffer stroke gate YF _DInput end connects, YF _DOutput, tie-time pulse control circuit K ₁, or the output tie-time pulse control circuit K of door H ₂, the clock circuit output terminal of being made up of crystal oscillator G and frequency dividing circuit FP is connected K respectively ₁And K ₂, K ₁And K ₂Output respectively as single-phase phase shortage timer J ₁With heterogeneous timer J ₂Input.Brilliant stop oscillator, frequency dividing circuit in time between the pulse control circuit all can buy from the market, phase shortage timer available electron counter or mechanical counter, working power is taken in electric substation's uninterruption power source or other loop standby power supplies.

Its principle of work is described below, three-phase U _A, U _B, U _CSignal is respectively three-phase 120 ° square-wave signal Ua, Ub, Uc each other after resistance R a, Rb, Rc dividing potential drop, diode Da, Db, Dc voltage stabilizing sampling, through Sheffer stroke gate, or the phase loss detector of door obtains P ₁, P ₂Signal according to AB=A+ Di B Morgan's theorem, is P but change into logical formula by the logical relation abbreviation of Fig. 2 ₁=UaUb+UaUc+UbUc, P ₂=Ua+Ub+Uc, when three-phase voltage, 120 ° each other of three-phase square waves, and each phase square wave is reported to the leadship after accomplishing a task overlapping about 60 ° mutually, by shown in Figure 3, the mid point Uo that floats this moment is the three-phase voltage mid point, then P ₁Bring out existing " 1 " signal, P ₂It also is one state.When scarce any phase time, the mid point Uo that floats then moves to the mid point of two-phase, and the two-phase square wave then differs 180 °, does not have the overlapping waveform of reporting to the leadship after accomplishing a task, and polar plot is shown in Figure 4, then P ₁Being " 0 " state, still is one state, lacks the two-phase example and lacks A and B phase time, and midpoint potential U floats _OEqual U _C, three square waves completely without, this moment P ₄Be " 0 " state, P ₂It also is " 0 " state.By shown in Figure 2, P ₁And P ₂Control signal is delivered to the time pulse control circuit K of single-phase timer respectively ₁Time pulse control circuit K with heterogeneous phase shortage timer ₂Remove to control the path through the time pulse To of frequency dividing circuit FP generation, work as P by crystal oscillator G ₁When signal often is " 0 " state, K then ₁Gate circuit is opened, and sprocket pulse To sends into single-phase phase shortage counter J ₁Count, work as P ₂When signal often is " 0 " state, then make K ₂Gate circuit open, sprocket pulse To sends into heterogeneous phase shortage timer J ₂In counting, add up single-phase and time of phase shortage mutually respectively.

The utility model circuit is simple, and debugging is convenient, can be widely used in electric industry department and under phase shortage metering state the phase shortage time be monitored to reach the correct metering of electricity consumption.

Claims

1, a kind of three phase watt-hour meter phase shortage calculagraph, it is characterized in that, it is by phase loss detector, clock circuit, time pulse control circuit, phase shortage timer and working power are formed, phase loss detector is made up of Sheffer stroke gate, OR circuit, input dropping resistor ka, kb, kc are connected with corresponding voltage stabilizing diode Ua, Ub, Uc be mutually 120 ° three-phase Ua, Ub, output terminal that a Uc3 square wave is taken a sample with or a H input end be connected, and respectively with corresponding Sheffer stroke gate YFa, YFb; YFb, YFc; YFc, YFa be connected voltage stabilizing diode Da, Db, the Dc anode links together and be connected Sheffer stroke gate YFa, YFb, YFc Sheffer stroke gate YF with unsteady mid point Uo _DInput end connects, YF _DOutput tie-time pulse control circuit K ₁, or output terminal and the time pulse control circuit K of door H ₂Be connected, crystal oscillator G is connected K respectively with the output terminal of the clock circuit that frequency dividing circuit FP forms ₁And K ₂, K ₁And K ₂Output is respectively as single-phase phase shortage timer J ₁With heterogeneous phase shortage timer J ₂Input.

2, three phase watt-hour meter phase shortage calculagraph according to claim 1 is characterized in that the phase shortage timer can be electronic counter or mechanical counter.