CN1096585A

CN1096585A - The high and low pressure electric power meter of automatic Control current mutual inductor ratio conversion

Info

Publication number: CN1096585A
Application number: CN 94103175
Authority: CN
Inventors: 余永宽
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-04-01
Filing date: 1994-04-01
Publication date: 1994-12-21

Abstract

The invention discloses a kind of high and low pressure electric power meter of automatic Control current mutual inductor ratio conversion, high pressure or low-voltage electric energy table by two groups of same sizes, two groups are differed about 1/5th by two or three pairs of rated current, high pressure that the secondary rated current is identical or low-voltage current mutual inductor, mechanical converter group and circuit spare connect to form.Can be under the situation that a bus is powered continuously, the variation of pressing the automatic switching current mutual inductor of height of a bus load electric current makes current transformer and electric energy meter operate in the scope of minimum error in dipping, reaches the accurate measurement purpose.

Description

The high and low pressure electric power meter of automatic Control current mutual inductor ratio conversion

It is indoor and outdoor to the present invention relates to power department, the high and low pressure electric power meter, mainly be that primary side to bus of high or low pressure and high or low piezoelectricity current transformer group is connected, the current transformer group, voltage transformer (VT) group secondary circuit is connected with the metering electric energy meter group and makes improvements.

Below " current transformer " abbreviation " CT ".

The CT of metering usefulness and the configuration of electric energy meter specification in the existing electric power meter, power supply department are by " 3.6,3.7 requirement are used one group two or join only a kind of no-load voltage ratio CT and one group of collocation method such as meritorious, idle, multi-rate meter among the electric power meter rule of management DL448-91.Because of there is error in CT, when load current was lower than CT calibration value 10%, ratio doubled, as was lower than 10% when following, and its ratio is more than several times, have up to tens times, and all be negative value.Induction type electric energy meter also has an obvious underloading dead electricity defective, just is to use the wide load electric energy table of present D86 series, when also having the 15W of being lower than following, also loses tally function.Adopt above-mentioned collocation method, metering actual load electric current is less than below 30%, and particularly less than below 10%, measuring apparatus metering electric energy accuracy descends, and has surpassed the error in dipping scope that measuring apparatus allows.At the about 15-20% of the annual short of electricity of China, " three electricity are done " in all parts of the country adopts the deficiency of power cuts to limit consumption way respite short of electricity, and that stand in the breach all is the commercial power rich and influential family, even adopts security personnel's electricity consumption way to avoid peak of power consumption for some users.76.3 ten thousand kilowatts of the maximum peak-valley differences of (selecting from " People's Daily " electric power-China's economic on October 10th, 93 another " bottleneck ") Jiangxi electricity consumption 93 years, and peak-valley difference is to be to increase superpotential (drawing from " Jiangxi Electric Power news in brief " 93.4 phases), some user power utilization character determination date rate of load condensate is very low, above-mentioned like this situation, electric power meter often are in the underrun state status and just seem more outstanding.

Purpose of the present invention, under standard and rules by country " DL448-91 ", " JJG307-88 " " JJG313-83 ", " JJG314-83 ", be to avoid the weak point of existing measuring method and improve can be under stoichiometric point connects electric power thus supplied, can change the CT no-load voltage ratio automatically by two kinds of situations of high and low load current, measure light, heavy load electric energy respectively, a kind of automatic Control current mutual inductor ratio of suitable existing measuring method is changed again, the high and low pressure electric power meter.

Purpose of the present invention, can reach by following measure: the present invention is by the high pressure or the low-voltage electric energy table of two groups of same sizes, two groups by two pairs or three pair, one time capacity differs about 1/5, the secondary capacity is identical, different high pressure or the low pressure CT that change, mechanical converter group and circuit spare, and combine with existing measuring method and form.The circuit spare first order converts the direct-flow signal voltage circuit to by bus load current sample and direct current regulation circuit is formed.Purpose is that to be subjected to the signal voltage that load current changes and not to be subjected to the constant operating voltage of load current variation also be reference voltage in order to obtain one.In the former circuit, the electric current of the sampling CT secondary side input of installing from bus, through intermediate current mutual inductor primary side closure, obtain AC signal voltage at secondary side parallel resistance two ends, finish the conversion of electric current → voltage, the direct-flow signal voltage by bridge rectifier, filtering send subordinate's electric circuit inspection, latter circuit, the ac low-voltage power supply that the electrical network of getting send subordinate's circuit as working power through the transformer step-down after bridge rectifier, filtering, the three terminal regulator voltage stabilizing.The second level is integrated package voltage comparator circuit and integrated package delay circuit.Compare from the signal voltage size and the former the circuit chip reference voltage of higher level's input, make discharge end shutoff or conducting control the latter circuit, be connected across working power two ends resistance and capacitor charging/discharging process after the series connection, just reach control this circuit chip discharge end conducting or shutoff by capacitor two ends charge or discharge voltage, make the midget relay solenoid that is connected on discharge end and working power positive pole get electric or dead electricity, make the closed of its contact or open.The third level is a control circuit, when midget relay adhesive or release, drive the closing of contact or open, make with its contact series connection after to be connected across the A.C. contactor at low-voltage alternating current power supply two ends closed simultaneously or open to control and be connected on the normally closed and normally opened contact of A.C. contactor two sockets that are connected across same low-voltage alternating current power supply two ends of connecting respectively and alternately be switched on or switched off low-voltage alternating current power supply.Because the solenoid in the forward and backward actuated piece of converter bank produces magnetic force by cable, actuated piece stayed mast adhesive before or after making, and another stayed mast discharges.The mechanical converter group, arrange by column by two or three identical unit mechanical converter, and between certain intervals is arranged, be installed on the same insulcrete, each cell translation device structure has 3 identical parts, also line up yi word pattern at regular intervals with on the fixing insulcrete of brass screws, parts are by suit on the static contact under the rectangular copper coin The sections support, retort stand two is fixed on the insulcrete by brass screws, this fixed copper screw terminal, in the retort stand both sides screw rod under pass insulating base, following static contact, put copper sleeve again, last static contact, stage clip, stage clip is regulated nut, pass the retort stand fixed by nut, last static contact two is connected on the terminals with the soft copper sheet, the rectangle motion bar cuts off material by rigid polyvinyl chloride and makes, middle four sides embeds the copper shell, motion bar passes three parts, on, the rectangle endoporus that copper sleeve on following static contact and the both sides screw rod is formed, formed a cell translation device, arrange by two or three this cell translation device column and to be fixed on four jiaos of same insulcretes on the insulcrete with brass screws and to be fixed on screw with screw again and to be fixed on two actuated piece centre positions on the iron plate, insulcrete and iron plate plane parallel, and a fixed gap arranged, before two or the three root unit converter motion bar, top, back two ends, before being connected to web joint, back link two ends or two ends and centre position, before being positioned at the cell translation device, the top of the stayed mast of back actuated piece, before being fixed on screw, the back link centre position, and two or three motion bar and stayed mast in one plane are parallel to each other and form the mechanical converter group, and be preceding, solenoid in the back actuated piece is communicated with respectively by cable plug and two sockets.What above-mentioned converter bank had two or three cell translation devices differs 1/5 with two groups by two pairs or three pair of capacity, high pressure that the secondary capacity is identical or low pressure CT corresponding matching, every bus input end need measuring mutually connects each cell translation device indirect line end respectively, every couple of large velocity ratio CT of back wiring termination primary side input end, preceding every pair of little transformation ratio current transformer primary side input end of wiring termination, be connected on after the parallel connection of every pair of big or small no-load voltage ratio CT primary side output terminal on bus output terminal of every phase, two groups of different no-load voltage ratio CT groups, secondary side is connected with each phase current coil of two groups of electric energy meters respectively, each phase voltage of potential winding is connected in parallel on the high voltage potential transformer secondary side or is directly parallel in bus of low pressure and respectively goes up mutually.When sample rate current mutual inductor secondary side current is sent in the circuit spare through control, make stayed mast adhesive in covering mouth of the front or rear actuated piece of converter bank, then or preceding stayed mast discharge, connecting rod before or after driving, motion bar is to stopping, make the terminals that are connected on each phase upconverter group of bus, big or little no-load voltage ratio CT first siding ring connects by the copper shell on the converter bank motion bar, reach continuous power supply, can change the CT no-load voltage ratio by the sampled signal size again, use two groups of electric energy meters to measure the electric energy in the electric energy metrical loop of forming with big or small no-load voltage ratio CT respectively.

Purpose of the present invention can also reach by following measure, and in the first order, one time the bus load sample conversion becomes in the direct-flow signal voltage circuit, and signal voltage adjustable potentiometer in parallel plays a part and can modulate after the rectification.The second level, the signal voltage of voltage comparator circuit integrated package control end and trigger end is introduced from two adjustable resistance centre taps that are connected in parallel on signal end respectively, playing can be when load current rises and drops to same amplitude, make discharge end conducting or shutoff, also be provided with RC and discharge and recharge time-delay, prevent that impact load from moving frequent influence to the mechanical converter group.Insert capacitor respectively over the ground at two integrated package control ends, prevent external interference.Also be provided with stage clip on each cell translation device and regulate nut, static contact is to the pressure of motion bar in the adjusting.

The present invention contrasts existing electric power meter metering method, owing to increased the mechanical converter group in the primary circuit, circuit spare, two groups of different transformation ratio current transformer groups of electric energy meter composition electric power meter that combines with two groups, can be under continuous electric power thus supplied of bus, automatically change the no-load voltage ratio of CT by the height of a bus load electric current, make CT and electric energy meter operate in the scope of minimum error in dipping, reach the accurate measurement purpose.

Below in conjunction with accompanying drawing and specific embodiments the present invention is elaborated again:

Fig. 1 is a circuit spare electrical schematic diagram in the measuring apparatus of the present invention

Fig. 2 is in the measuring apparatus of the present invention, cell translation device front view (FV)

Fig. 3 is in the measuring apparatus of the present invention, cell translation device outboard profile

Fig. 4 is in the measuring apparatus of the present invention, the converter bank scheme of installation

Fig. 5 is in the measuring apparatus of the present invention, and the three low-temperature measurement mode of measuring electric current mutually of getting is measured the electric energy schematic diagram

Fig. 6 is in the measuring apparatus of the present invention, gets the high pressure measurement mode of two-phase measurement electric current and measures the electric energy schematic diagram

As shown in Figure 1: circuit spare of the present invention, first group of current sampling circuit and direct current regulation circuit, preceding circuit sampling current mutual inductance CT ₁Secondary current (300/5ALQG-0.5) is by K ' ₂, K ' ₁Binding post is introduced intermediate current mutual inductor L _BPrimary side forms closed-loop path, secondary side and resistance R ₁Two ends in parallel pressure drop input is by D ₁-D ₄The bridge rectifier circuit of forming, the direct-flow signal voltage of output is connected across electrolytic condenser C ₁, voltage stabilizing diode W ₁(2CW ₅₉) output to subordinate's circuit behind the two ends.From the ac low-voltage power supply that electrical network comes, nominal voltage 220V introduces step-down transformer T from binding

post

5,6 two ends ₂Primary side, secondary side joint bridge rectifier circuit D ₅-D ₈, output terminal filter capacitor C in parallel ₅, C ₆After be connected in parallel on three terminal regulator W ₇₈₀₇, 1,2 ends, 2 end ground connection, three

terminal regulator

2,3 ends are shnt capacitor C again ₇Filtering once more, output, output terminal V _DdDC voltage 7V over the ground, the second level, in comparison and the delay circuit, IC ₁, IC ₂Be time base circuit integrated package NE ₅₅₅, use adjustable potentiometer WR ₂Resistance R ₂With adjustable potentiometer WR ₃, R ₃After the series connection, parallel connection is connected across the signal voltage two ends respectively, and two adjustable potentiometer upper end points in parallel meet signal voltage input end V.The potentiometer centre tap meets IC respectively ₁2 pin, 6 pin, resistance R ₄With electrolytic condenser C ₃Be connected across on the working current 7V resistance R after the series connection ₄One termination V _Dd, series connection point meets IC ₁7 pin, other end meet back circuit chip IC ₂On 6 pin, the 2 pin point in parallel, IC ₁, IC ₂4 pin, 8 pin, meet working power V _DdOn the point, 5 pin are respectively through capacitor C ₂, C ₄Ground connection prevents external interference, the direct ground connection of 1 pin, IC ₂7 pin connect one of midget relay (JRX-13F-1/006) solenoid, and the other end meets working power V _DdOn, as K ' ₂, K ' ₁The sampling secondary current of input through first group of circuit, electric current → voltage transitions, is input to the IC in the circuit of the second level below 1 ampere the time ₁6 pin, 2 pin voltage-to-grounds are respectively less than 2/3V _Dd, 1/3V _Dd, IC ₁7 pin turn-off, and operating voltage is passed through resistance R ₄To capacitor C ₃Charging over the ground, time constant is after 2 minutes, C ₃Last charging voltage also is IC ₂6 pin, 2 pin voltages are greater than 2/3V _Dd, IC ₂7 pin conductings are connected across working power V _DdAnd IC ₂The midget relay K of 7 pin ₂(JRX-13F-1/006) solenoid gets electronic work, normally opened contact J _1-1Closed.As K ' ₂, K ' ₁The sampling secondary current of input through first order circuital current → voltage transitions, is input to the IC in the circuit of the second level more than 1 ampere the time ₁6 pin, 2 pin voltage-to-grounds are respectively greater than 2/3V _Dd, 1/3V _Dd, IC ₁7 pin conductings, C ₃On capacitance voltage pass through IC rapidly ₁It is zero that 7 pin discharge over the ground, makes IC ₂6 pin, 2 pin voltages are less than 1/3V _Dd, IC ₂7 pin turn-off, and are connected across IC ₂7 pin and the working power two ends are miniature when continuing device K ₂Dead electricity makes normally opened contact J _1-1Recover off-state.In the third level control circuit, J ₂A.C. contactor (JTX-2Z) and its contact J _1-1Series connection also is connected across step-down transformer T ₂Primary side, 5,6 binding posts are connected on 5,6 terminals from the low pressure 220V AC power that electrical network comes.Pass through J from the 220V alternating current of

terminals

5,6 inputs ₂J _2-1Normally closed contact is connected in parallel on socket CZ ₁Two ends, the 220V AC power is also passed through J ₂J _2-2Normally opened contact is connected in parallel on socket CZ ₂Relay J is worked as at two ends ₂Must be electric, normally opened contact J _2-2Closure, the 220V AC power is passed through J ₂J _2-2The contact makes socket CZ ₂Charged, work as relay J ₂Dead electricity, J _2-1It is closed that recover the contact, and the 220V AC power is by contact J _2-1The contact makes socket CZ ₁Charged.

As shown in Figure 2: wherein each parts of cell translation device of the present invention all are made of following structure, pass from insulating base 1 bottom surface by two screw rods 10, cover loads static contact 3 and is set with a copper sleeve 5, goes up static contact 6, is set with a stage clip 7 again, regulates nut 8, passes

Sections support 9 tops, use fixed by nut, following static contact 3, retort stand 9 two, be fixed on the insulcrete 1 by binding post 2.1, last static contact 6 two and two binding posts 2.1, connect with soft copper sheet 4, on, following

static contact

6,3 and be enclosed within the rectangle that two copper sleeves 5 on the screw rod 10 surround and load onto a motion bar 12, one section outer four sides embeds copper shell 11 in the middle of the motion bar 12, motion bar 12 thickness are greater than 3 millimeters of copper sleeve 5 height, width is sleeved on the screw rod 10 between the copper sleeve 1 millimeter of distance less than two, between the copper sleeve on the screw rod 10 5 with 0.2 millimeter gap movable cooperate and can center on screw rod 10 freely rotate the side friction power when taking in sail bar 12 rectilinear motions.

As shown in Figure 3: the cell translation device in the converter bank of the present invention is by the parts of three same size shapes, 27.1,27.2,27.3 line up yi word pattern, and between equate at interval, for example: current transformer is joined 300/5A, 30 millimeters at interval, come on the straight line, with terminals 2.1,2.2,2.3 be fixed on the insulating base 1, the wideest length is 108 millimeters before and after three retort stands, the copper shell of copper shell 11 long 92 millimeters embeddings of embeddings in the middle of the motion bar 12 and the motion bar light face of making of pvc material are smooth, smooth, long 200 millimeters of motion bar, motion bar 12 passes three parts 27.1,27.2,27.3 on, following

static contact

6,3 energy straight lines move back and forth.

As shown in Figure 4, mechanical converter group of the present invention, get three by metering method and measure electric current mutually, by three cell translation device 24,25,26 by column's arrangement, be fixed on the insulcrete by terminals, choose size and make three cell translation device motion bars 12.1,12.2,12.3 the fore head insulator is with preceding web joint 15.1,15.2,15.3 be attached on the front rod 14 with screw, preceding actuated piece 22 is placed in front rod 14 the place aheads and is fixed on the iron plate 29 with screw, and preceding web joint 15.2 other end heads are fixed together with screw and preceding stayed mast 17 heads, front and back actuated

piece

22,23 specifications (30 millimeters of MQ-25N strokes, rated voltage 220V, current on time 100%) three cell translation device motion bars 12.1,12.2,12.3 back insulator head back web joint 18.1,18.2,18.3 and be connected on the back link 13 with screw, and back web joint 18.2 other ends are fixed together with screw and back pull bar 16 heads, back actuated piece 23, be placed in back link 13 rears and be fixed on the iron plate 29 with screw, insulating base 1, four jiaos are fixed on the iron plate 29 with screw 28, and surface level is parallel mutually.The converter bank electrical separation is by " high-low pressure electrical design handbook ", " JB911-66 " requirement.The solenoid of current actuated piece 22 gets, during the electromagnetism wire ring dead electricity of back actuated piece 23, preceding stayed mast 17 pulling front rods 14, driving motion bar 12.1,12.2,12.3 finishes to stroke, make the preceding terminals 2.4,2.1,2.7 and the indirect line end 2.5,2.2,2.8 of each cell translation device can make short circuit on the electric property respectively simultaneously by copper shell 11.2,11.1,11.3 respectively, back terminals 2.6,2.3,2.9 and indirect line end 2.5,2.2,2.8 are opened a way on the electric property respectively simultaneously.When after the solenoid of actuated piece 23 get, before during the solenoid dead electricity of actuated piece 22, the motion bar 12.1,12.2,12.3 that back pull bar 16 pulling back links 13 drive each cell translation device finishes to stroke, terminals 2.4,2.1,2.7 and indirect line end 2.5,2.2,2.8 can make on the electric property respectively simultaneously and open a way before making, make back terminals 2.6,2.3,2.9 and indirect line end, 2.5,2.2,2.8 can make short circuit on the electric property respectively simultaneously.

From the graph 2, Fig. 3, Fig. 4 describes in detail and draws by above-mentioned wherein a kind of collocation method, 30 millimeters of the front and back rectilinear motion distances of three motion bar maximums of converter bank, it also is the actuated piece range, in the movable root maximum linear move distance process, because of three copper shells on the motion bar are the air line distance of the front and back parts lateral width mid point point-to-point transmission of cell translation device for long 92 millimeters, so, rectilinear motions were apart from the process before and after three motion bars drove three copper shell maximums, make three cell translation devices before, in, between three terminals in back contact simultaneously respectively on the electric property mutually conversion be: front or rear terminals and intermediate connection short circuit → three terminals short → front or rear terminals and intermediate connection open circuit → back or preceding terminals and intermediate connection terminal shortcircuit.

As shown in Figure 5: the present invention uses at the three-phase four-wire system electric energy metrical, adopts the converter bank of three cell translation devices.For example: large velocity ratio is got 300/5A specification, CT ₃, CT ₇, CT ₅Current mutual inductor with high transforming ratio is 60/50A by 1/5 of a capacity of large velocity ratio, CT ₂, CT ₆, CT ₄Little transformation ratio current transformer, CT ₂And CT ₃, CT ₆And CT ₇, CT ₄And CT ₅Three pairs of current transformers, primary side output terminal L respectively ₂Parallel connection, contact M ₁, M ₂, M ₃Connect respectively and once export bus A ' B ' C ', electric energy meter DT86-1, A element current coil input end output terminal and CT ₂Secondary side K ₁, K ₂The end series connection, B element current coil input end output terminal and CT ₆Secondary side K ₁, K ₂The end series connection, C element current coil input end output terminal and CT ₄Secondary side K ₁, K ₂The end series connection.Electric energy meter DT86-2, A element current coil input end, output terminal and CT ₃Secondary side K ₁, K ₂The end series connection, B element current coil input end, output terminal and CT ₇Secondary side K ₁, K ₂The end series connection, C element current coil input end, output terminal and CT ₅Secondary side K ₁, K ₂The end series connection.

Electric energy meter DT86-1, DT86-2, a of voltage component, b, c, o are connected in parallel on bus A ' B ' C ' O ' mutually respectively and go up CT mutually ₂, CT ₃, CT ₆, CT ₇, CT ₄, CT ₅Primary side input end L ₁Connect converter bank respectively with cable, bus of 2.4,2.6,2.1,2.3,2.7,2.9, buses of forward and backward terminals.Parallel operation group indirect line end 2.5,2.2,2.8 is switched through in A, B, C input respectively, socket CZ in socket CZ2, the back actuated piece 23 usefulness electric cable connection circuit spares in the preceding actuated piece 22 usefulness electric cable connection circuit spares of converter bank ₁, transformer T in the circuit spare ₂Primary side binding post 5.6 terminations bus A, an O go up sample rate current mutual inductor CT mutually ₁Be connected on a bus B and go up secondary side K mutually ₁, K ₂Terminals are introduced intermediate current mutual inductor K ' in the circuit spare with cable ₁, K ' ₂Terminals are when being connected on bus B phase up-sampling CT one time ₁Secondary side is input to the binding post K ' in the circuit spare ₁, K ' ₂Secondary current is less than below 1 ampere the time, and just a bus current reaches rated current of current mutual inductor with high transforming ratio below 1/5, circuit control in circuit spare, socket CZ ₂Charged, CZ ₁Not charged, socket CZ ₂, CZ ₁Pass through cable respectively, plug and preceding actuated piece 22, back actuated piece 23 is communicated with, actuated piece 22 gets before the institute, back actuated piece 23 dead electricity, preceding stayed mast 17, pulling front rod 14, drive motion bar 12.1,12.2,12.3 make the preceding terminals 2.4 of each cell translation device, 2.1,2.7 and indirect line end 2.5,2.2,2.8 respectively by copper shell 11.2,11.1,11.3 contact respectively simultaneously, a bus A, B, C three-phase load electric current is from indirect line end 2.5,2.2,2.8 input is through copper shell 11.2,11.1,11.3 to preceding terminals 2.4,2.1,2.7 respectively by a bus cable 19.4,19.1,19.7 to CT ₂, CT ₆, CT ₄Primary side L ₁The end through primary winding respectively from and coupling head M ₁, M ₂, M ₃To output bus A ', B ', C ', CT ₂, CT ₆, CT ₄Secondary side is responded to secondary current respectively from K ₁, K ₂End and electric energy meter DT86-1, the current coil closure of A, B, C current element, each is gone up mutually because of the voltage component of electric energy meter DT86-1 respectively is in parallel at bus, and electric energy meter DT86-1 measures underload electric current electric energy.CT ₃, CT ₇, CT ₅Because of the effect of each cell translation device of converter bank, the primary side open circuit, electric energy meter DT86-2 stops walking.

When being connected on bus B phase up-sampling current transformer CT one time ₁Secondary side is input to binding post K ' in the circuit spare ₁, K ' ₂Secondary current greater than more than 1 ampere the time, just bus current reach rated current of current mutual inductor with high transforming ratio more than 1/5 until maximal value, circuit control in circuit spare, socket CZ ₂Dead electricity, CZ ₁Must be electric, socket CZ ₂, CZ ₁Be communicated with by cable plug and preceding actuated piece 22 back actuated pieces 23 respectively, the solenoid of back actuated piece 23 gets, back pull bar 16 is by back link 13, drive motion bar 12.1,12.2,12.3 finish to stop to stroke, make terminals 2.6 behind each cell translation device, 2.3,2.9 and indirect line end 2.5,2.2,2.8 respectively by copper shell 11.2,11.1,11.3 contact respectively simultaneously, a bus A, B, C phase load electric current is respectively by indirect line end 2.5,2.2,2.3 input is through copper shell 11.2,11.1,11.3 to back terminals 2.6,2.3,2.9 respectively by a bus cable 19.6,19.3,19.9 to CT ₃, CT ₇, CT ₅Primary side L ₁Input end through primary winding respectively from and contact M ₁, M ₂, M ₃To output bus A ' B ' C ' phase CT ₃, CT ₇, CT ₅Secondary side is responded to secondary current respectively from K ₁, K ₂End and electric energy meter DT86-2, the series connection of the current coil of A, B, C current element, each is connected in parallel on respectively on each phase voltage of bus mutually because of electric energy meter DT86-2 voltage component, and electric energy meter DT786-2 measures high load capacity electric current electric energy, CT ₂, CT ₆, CT ₄Because of the effect of each cell translation device of converter, the primary side open circuit, electric energy meter DT86-1 stops walking, and this device uses in low pressure 380/220V electric pressure, and total electric degree of metering electric energy is:

Electric energy meter DT86-1 copies the ratio+electric energy meter DT86-2 that sees electric degree * little transformation ratio current transformer and copies ratio=total electric degree of seeing electric degree * current mutual inductor with high transforming ratio

As shown in Figure 6: stoichiometric point is the above electric pressure of high pressure 10KV, the three-phase three tier structure, getting the metering method of two-phase measurement electric current and the low pressure 380/220V low-temperature measurement mode among Fig. 5 compares, connection principle, control principle is the same, and difference is each phase voltage of voltage component and each phase voltage parallel connection of voltage transformer pt secondary side of electric energy meter group, is input to the low-voltage alternating-current electric current of 5,6 terminals in the circuit spare, be to use step-down transformer T, secondary side T _1-4, T _1-3Directly input, step-down transformer, T primary side T _1-2, T _1-1Be connected in parallel on bus A, the B two-phase, because of get two-phase measure in the current converter group equipped less cell translation device 25 current transformer groups join less a pair of, CT ₆, CT ₇, but CT ₂, CT ₃, CT ₄, CT ₅Adopt the high-voltage mutual inductor specification, the total electric degree of metering electric energy is: the meritorious or idle DX86-1 of DS86-1 copies and sees that the meritorious or idle DX86-2 of the little transformation ratio current transformer ratio of electric degree * high pressure * high voltage potential transformer ratio-DS86-2 copies ratio * high voltage potential transformer ratio=total electric degree of seeing electric degree * high pressure current mutual inductor with high transforming ratio.

Claims

1, a kind of high and low pressure electric power meter of automatic Control current mutual inductor ratio conversion, have according to the stoichiometric point electric pressure, bus load magnitude of current is by the requirement of " electric power meter rule of management " and metering method, configuration current transformer, voltage transformer (VT), electric energy meter use specification, and first and second loop and web member thereof are formed the electric power meter of electric current, voltage circuit first and second coil series, parallel, measure meritorious, idle and other electric degree numbers of size variation load in the tested bus.The present invention is characterised in that: this device also has

(a) respectively by the high pressure or the low-voltage electric energy table of two groups of same sizes, two groups are differed about 1/5th by two pairs or three pair of rated current, high pressure that the secondary rated current is identical or low-voltage current mutual inductor, mechanical converter group and circuit spare, at each phase input end of bus, in the middle of each phase primary side input end of different transformation ratio current transformer groups with two groups, connect one group of mechanical converter group, conversion is connected on the conversion of each phase primary side on-off alternating state of the different transformation ratio current transformer group of each phase primary side, mutual inductor group output terminal respectively is in parallel and a little connects each phase output terminal of bus one time, each phase current loop of the high pressure of two groups of same sizes or low-voltage electric energy table is connected on each phase current mutual inductor secondary side of different no-load voltage ratios respectively, each is connected in parallel on voltage circuit bus-bar potential transformer secondary side mutually jointly each is gone up or be directly parallel in bus of low pressure mutually each is gone up mutually, and the solenoid of the actuated piece at converter bank two passes through the umbilical cable line and is connected with socket in the circuit spare.

(b) circuit spare is made up of three grades of circuit: the first order once bus load current sample converts direct-flow signal voltage circuit and direct current regulation circuit to, wherein be contained in the sample rate current mutual inductor secondary current input intermediate current mutual inductor first siding ring on the bus and form the closed-loop path, intermediate current mutual inductor second siding ring also connects a small resistor realization electric current → voltage transitions, be input to the bridge rectifier circuit input end, output terminal also connects the adjustable potentiometer two ends, adjustable potentiometer centre tap and ground end filter capacitor in parallel, each one of stabilivolt, AC signal voltage is through rectification, filtering, send the next stage signal input part behind the amplitude limit.Other has the low-tension supply of electrical network to be transformed into the light current pressure through step-down transformer, through bridge rectifier, filtering, three terminal regulator voltage stabilizing, send the next stage circuit, as operating voltage again.The second level: be integrated package voltage comparator circuit and integrated package delay circuit, from the signal voltage of higher level input and at the corresponding levels before the reference voltage of circuit time base circuit integrated package voltage comparator circuit compare and control back circuitous resistance and capacitors in series and form and discharge and recharge, the height control back circuit time base circuit integrated package of capacitor voltage at both ends is controlled the closed of midget relay contact again or is opened.The third level is a control circuit, when midget relay adhesive of upper level circuit or release, make the midget relay closing of contact or open, simultaneously also make the solenoid that is connected on this contact A.C. contactor be connected across the A.C. contactor adhesive or the release at low-voltage alternating current power supply two ends, after making the normally closed and normally opened contact that is connected on A.C. contactor respectively, two sockets that are connected across the low-voltage alternating current power supply two ends are alternately connected low-voltage alternating current power supply.

(c) mechanical converter group, by the metering method requirement, need get two-phase or three phase load current measurement situation, cooperate by two or three unit mechanical converter and actuated piece and to form, each unit mechanical converter structure is identical, be installed on the same rigid polyvinyl chloride insulcrete, between each unit mechanical converter and and actuated piece between, electric insulation each other, gap size is pressed and is used at concrete metering points of electric energy each other, electric pressure is just shone " height; low-voltage electrical apparatus design manual " " JB911-66 " electric clearance and is required different.The cell translation device is by three parts that geometric configuration is measure-alike, at regular intervals, mutually insulated is lined up yi word pattern, be fixed on the insulcrete, each accessory size of parts and three parts installation interval size, the load current size and the actuated piece range that allow to pass through are selected by using in concrete metering points of electric energy rated current amount and conversion performance requirement.These parts are by suit on the static contact under the block length bar copper coin

The sections support, the outer two of retort stand is fixed on the insulating base by brass screws, this fixed screw is again terminals, insulating base is passed with screw rod in both sides in the retort stand, following static contact, put copper sleeve, copper sleeve also can freely center on the screw rod rotation, put static contact again, stage clip, stage clip is regulated the gong cap, passing retort stand fixes with the gong cap, last static contact two is connected on the terminals with the soft copper sheet, the rectangle motion bar is made with the rigid polyvinyl chloride insulating material, and middle one section four sides embeds the copper shell, pass three parts on, the rectangle endoporus that the copper sleeve on following static contact and both sides surrounds, form a cell translation device, add certain thrust to motion bar one end is anti-, can make motion bar rectilinear motion in three supports, and and last, following static contact contact, the stage clip of three parts is regulated the gong cap, and static contact is to the pressure of motion bar on the scalable stage clip.Arrange by column by two of above-mentioned same structures or three cell translation device, certain intervals is arranged each other, with binding post be fixed on the same plate insulcrete and before four jiaos of insulcretes are fixed on screw, back actuated piece is fixed in the middle of two actuated pieces on the iron plate by screw, one fixed gap is arranged between iron plate and the insulcrete, and plane parallel, before each cell translation device motion bar, before the top, rear end is used, before back web joint is connected to, the two ends of back link and centre position, before web joint other end on the front-rear linkage centre position connects with screw, before the back actuated piece, the top of back pull bar, before making, back pull bar and be connected to three cell translation device and be positioned at the motion bar of buffer module on the straight line on a plane, and and other two motion bars are parallel to each other, have only two cell translation devices, the converter bank centre position cell translation device of the composition of three cell translation device just is installed less.Front and rear connecting rods is made with rigid polyvinyl chloride material.When front or rear actuated piece solenoid gets, back or preceding actuated piece solenoid dead electricity, its interior stayed mast adhesive in covering mouth of actuated piece before or after it, and connecting rod before or after directly driving, it is also equidirectional to drive each cell translation device motion bar by front or rear connecting rod, the synchronous linear motion, to the stop motion of actuated piece range, the front or rear terminals of each cell translation device are in contact with one another by copper shell on the motion bar and indirect line end hardware, can make short circuit on the electric property, perhaps because the finite length of copper shell moves to the other end, back or preceding terminals and indirect line end are isolated because of the motion bar upper insulator, and electric property is an open circuit.

(d) high pressure of two groups of same sizes or low-voltage electric energy table and two groups are differed about 1/5th by two pairs or three pair of capacity, and the secondary capacity is identical, the high pressure of different no-load voltage ratios or low-voltage current mutual inductor; Be need be to get two-phase or three phase load electric current by using at the electric energy metrical point measurement, metering points of electric energy electric pressure and a rated current amount dispose.For example: rated current 300 ampere-capacities, join the 300/5A current transformer 2 or 3, join 2 or 3 of 60A/5A current transformer by 1/5 primary current amount again, 2 couple who partners with 300/5A and 60/5A or 3 pairs and be used with the converter bank that two or three unit mechanical converter are formed.Every bus input end need measuring mutually, connect each cell translation device respectively and be positioned at middle accessory terminals, every pair of large velocity ratio of wiring termination behind the position is for example: 300/5A current transformer primary side input end, every pair of little no-load voltage ratio of wiring termination before the position, for example: 60/5A current transformer primary side input end, every pair big; the primary side output terminal of little no-load voltage ratio electric current mutual inductance also is connected on bus output terminal of every phase; the high pressure of two groups of same sizes or low-voltage electric energy table; by gaining merit of identical specification; idle; multi-rate meter etc. need be selected combination by metering method and stoichiometric point electric pressure; wherein one group of every phase current element connected in series of electric energy meter is in every pair of current mutual inductor with high transforming ratio group secondary side loop; another organizes every phase current element connected in series in every pair of little transformation ratio current transformer group secondary side loop, and the voltage circuit of every phase voltage element of two groups of electric energy meters is connected in parallel on voltage transformer secondary side jointly or is directly parallel in a bus and respectively goes up mutually.When after actuated piece solenoid dead electricity, preceding actuated piece solenoid gets, stayed mast adhesive in covering mouth, drive front rod, motion bar is to stopping, each phase current of bus is from each cell translation device indirect line end input, by copper shell the past terminals on the motion bar, every pair little transformation ratio current transformer primary side input end input, from each phase output terminal output of every pair of current transformer primary side output terminal to time bus in parallel, every pair little transformation ratio current transformer secondary side each the phase current coil of electric energy meter group of connecting respectively gets electric metering electric energy.Current actuated piece solenoid dead electricity, after cause part spare solenoid get electric, stayed mast adhesive in covering mouthful, drive back link, motion bar are to stopping.Each phase current also is from each cell translation device indirect line end input, by copper shell on the motion bar, primary side input end input from the back terminals to every pair of current transformer, the bus output terminal output from every pair of current transformer primary side output terminal in parallel to each phase, every pair of current mutual inductor with high transforming ratio secondary side obtains secondary current, is connected every pair of each phase current coil of current mutual inductor with high transforming ratio electric energy meter group and gets electric metering electric energy.

2, the high and low pressure electric power meter of a kind of automatic Control current mutual inductor ratio conversion according to claim 1 is characterized in that:

(e) the circuit spare first order, sample rate current mutual inductor specification is the same with the current mutual inductor with high transforming ratio specification of electric energy metrical configuration.Through W ₇₈₀₇The working current 7V of voltage stabilizing output, intermediate current mutual inductor secondary voltage and primary current have linear relationship, but the intermediate current transformer iron core is saturated when primary current surpasses rated current about 4/5 or more up to the primary current maximal value, make secondary voltage unlikely excessive, reduce core volume like this, can alleviate superpotential, overload requirement again, again through W to subsequent conditioning circuit ₁2CW ₅₉Amplitude limit alleviates subsequent conditioning circuit pressure once more.The second level, integrated package are NE ₅₅₅The time base circuit integrated package when higher level's sample rate current mutual inductor secondary current rises but less than below 1 ampere, also is that rated current amount 1/5th is changed through the intermediate current mutual inductor when following, and the direct-flow signal voltage of rectification, output is input to IC ₁6 pin, 2 pin signal voltages are respectively less than reference voltage 2/3V _Dd, 1/3V _Dd, IC ₁7 pin turn-off, C ₃Charging, time constant is after 2 minutes, IC ₂6 pin, 2 pin voltages are greater than reference voltage 2/3V _Dd, IC ₂7 pin conductings are connected across IC ₂Relay K on 7 pin and the working power positive pole ₁(JRx-13F-1/006) must be electric, contact K _1-1Connect, because its contact and another relay K ₂(JTx-Ac) solenoid is the low-voltage alternating current power supply two-stage that series connection is connected across electrical network, makes K ₂Must be electric, simultaneously, because of its normally opened contact K _2-2Closure makes again and normally opened contact K _2-2Connect, be connected across the socket CZ of low-voltage alternating current power supply two-stage ₂Charged.When sample rate current mutual inductor secondary current rises to more than 1 ampere, be input to IC ₁6 pin, 2 pin signal voltages are greater than reference voltage 2/3V _Dd, 1/3V _Dd, IC ₁7 pin conductings, C ₃Last voltage makes IC by the discharge rapidly over the ground of 7 pin ₂2 pin voltages are less than 1/3V _DdMake IC ₂7 pin turn-off, and make relay K ₁Dead electricity, its contact K _1-1Disconnect, make to be connected on its contact relay K ₂Be connected across low-voltage alternating current power supply two-stage electromagnetic coil losing electricity and make normally closed contact K _2-1Connect, simultaneously, because of its normally closed contact K _2-1Series connection is connected across the socket CZ of low-voltage alternating current power supply two-stage ₁Charged.

(f) mechanical converter group, rated travel are more than 30 millimeters, and current on time 100% also can be selected MZS for use ₁The series Brake Electromagnet, rectilinear motion ultimate range is front or rear actuated piece adhesive stroke before or after the motion bar, copper shell on the every motion bar of converter bank moves to the other end with motion bar from a synchronous linear synchronously to be stopped, can make parts in each cell translation device before, during and after terminals each other because of copper housing contacts and disengaging on the motion bar, the electric property co-relation is by front or rear terminals and intermediate connection terminal shortcircuit → three terminals short → front or rear terminals and indirect line end open circuit → back or preceding terminals and intermediate connection terminal shortcircuit.Motion bar, front and rear connecting rods, bedplate is made with rigid polyvinyl chloride material or other insulating material.

(g) metering electric energy meter is selected D for use ₈Or D ₈₆Series is pressed stoichiometric point electric pressure difference, selects the high and low pressure current transformer that is fit to the stoichiometric point electric pressure for use.The present invention can be installed in PJ series monoblock type by the requirement of " DL447-91 " electric energy metrical cabinet, the interior as " PJ of high and low pressure electric energy metrical cabinet again ₁-D " the electric energy metrical cabinet, in the casing of bottom clamshell doors, be suitable for exchanging 50HZ, rated voltage 0.38-10KV, rated current 100-1000A.The present invention also can cooperate the outdoor combined high-voltage power metering box-shaped formula of the extensive oil-immersed self-cooled JLSJW type that adopts of present China and other manufacturer production, be fit to voltage 35KV-6KV, primary current 20-6000A, strengthen batch meter casing and instrument box volume, by described each bar of claim 1, the mechanical converter group is installed in the batch meter casing, the low-voltage alternating current power supply that circuit spare needs can directly use with the step-down transformer step-down with busbar voltage of batch meter inner high voltage, two groups of electric energy meters of circuit spare and metering usefulness, be installed in the instrument box, form the automatic switching current mutual inductor ratio of outdoor mating type high-voltage power metering case.