CN1963533A - Circuit and method for preventing shunt running in electric energy measurement - Google Patents

Abstract

This invention discloses one anti-creeping circuit in energy meter, which comprises energy sum unit and sample meter, wherein, the sample meter is under control of simultaneous signal control to sum input power sample times; when sample times are over, processing inner clearing and requiring energy sum unit for inner clearing; according to energy sum unit require for inner clearing. This invention discloses other energy meter anti-creeping circuit and one method and other anti-creeping method.

Description

Anti-shunt running circuit and creeping prevention method in the electric energy metrical

Technical field

The present invention relates to the electric energy metrical technology, particularly anti-shunt running circuit and the creeping prevention method in the electric energy metrical.

Background technology

Electric energy metrical is meant: the energy that metering active power takes place.Yet in the actual power metering process, power input is generally by being formed by stacking as the DC component of active power with as the AC compounent of frequency about 100 hertz of reactive power.When the input of foreign current and voltage made that DC component is zero, AC compounent still might exist, and the electric energy metrical result of this moment is the electric energy metrical result to reactive power, i.e. error.

Above-mentioned phenomenon is the shunt running in the electric energy metrical.This phenomenon makes the user when electricity consumption not, is still chargeed, and causes damage to the user.

Fig. 1 a is the structural drawing of anti-shunt running circuit 1 in the prior art.As shown in Figure 1a, the anti-shunt running circuit in the existing electric energy metrical comprises: absolute value element 101, threshold cell 102, comparer 103 and output control unit 104.

Absolute value element 101 is used for power input is taken absolute value, and the absolute value of power input is offered comparer 103;

Threshold cell 102 is used to store pre-set threshold, and offers comparer 103;

Comparer 103 is used under the situation of absolute value more than or equal to threshold value of power input, sends gating signal to output control unit 104;

Output control unit 104 is used for according to from the gating signal of comparer 103, and power input is sent to energy accumulation unit in the ic for energy metering; When the gating signal of not receiving from comparer 103, forbid that the energy accumulation unit in the ic for energy metering adds up.

Fig. 1 b is the structural drawing of anti-shunt running circuit 2 in the prior art.Shown in Fig. 1 b, the anti-shunt running circuit in the existing electric energy metrical mainly comprises: timing module, counting module and reset circuit.

Timing module is made up of the d type flip flop that some bands reset; Counting module is made up of the plus-minus counting unit that some bands reset; Reset circuit and up-down signal, major clock, master reset clock, timing module, counting module connect carries out logical process, produces anti-shunt running reset signal.

If the timing module meter is expired M second, counting module is not also exported overflow indicator, and then reset circuit produces reset signal, with counting module and timing module zero clearing, judges that promptly current state is the shunt running state, does not carry out the metering of electric energy.

Though above-mentioned two anti-shunt running circuit can reduce the influence that shunt running brings, but still have following problem:

1) because there is the ripple that is produced by AC compounent in power input, when the ripple of AC compounent when threshold value is shaken up and down, still have the part reactive power to be measured, therefore, the control accuracy deficiency of anti-shunt running circuit 1 anti-shunt running as shown in Figure 1a, can not realize high-precision anti-shunt running control, and the reliability of anti-shunt running is not high yet.

Fig. 2 is the ripple synoptic diagram of power input.As shown in Figure 2, when power input was positioned at situation on the threshold value for some time under, AC compounent still can be measured.

2) the anti-shunt running circuit 2 shown in Fig. 1 b solved the problem that anti-shunt running circuit 1 exists to a certain extent, but still there is following problem in anti-shunt running circuit 2:

Electric energy metrical is the energy that metering active power takes place, active power P ₀Computing formula be:

${\mathrm{<figure-callout\; id="0"\; label="P"\; filenames="A20061016222700381.png,A20061016222700391.png"\; state="\{\{state\}\}">P</figure-callout>}}_0=\frac{V\&times;I}{2}\cos \mathrm{\&alpha;}$

Wherein, V is a voltage, and I is an electric current, and α is the phase place angle of electric current and voltage.

If α is near 90 degree or-90 degree, i.e. load is not pure resistive load, and then active power may show very for a short time owing to cos α is very little, often is left in the basket when metering.But how little the active power no matter ic for energy metering receives is, all is to measure it, and therefore, anti-shunt running circuit 2 can be ignored the metering to active power, thereby also have the not high problem of reliability when electric current and voltage phase place angle is very little.

As seen, the anti-shunt running circuit in the existing electric energy metrical is realized anti-shunt running in the electric energy metrical by judging whether current power input should be measured, and the precision of anti-shunt running control is not high, and reliability is also lower.

Summary of the invention

In view of this, a fundamental purpose of the present invention is, the anti-shunt running circuit in a kind of electric energy metrical is provided, and can improve the control accuracy and the reliability of anti-shunt running.

Another fundamental purpose of the present invention is, the anti-shunt running circuit in the another kind of electric energy metrical is provided, and can improve the control accuracy and the reliability of anti-shunt running.

Another fundamental purpose of the present invention is, a kind of energy meter anti-creeping is provided, and can improve the control accuracy and the reliability of anti-shunt running.

Also fundamental purpose of the present invention is, another kind of energy meter anti-creeping is provided, and can improve the control accuracy and the reliability of anti-shunt running.

Based on an above-mentioned fundamental purpose, the invention provides the anti-shunt running circuit in a kind of electric energy metrical, comprising: energy accumulation unit and sampled point counter, wherein,

Sample to the power input in the ic for energy metering under the control of synchronizing signal in described energy accumulation unit, and sampled result is carried out energy accumulation; When the energy accumulation result was overflowed, request sampled point counter carried out inner zero clearing, and the request metering units carries out electric energy metrical; According to the request of sampled point counter, carry out inner zero clearing;

Described sampled point counter adds up to the sampling number of power input under the control of described synchronizing signal; When the sampling number accumulation result overflows, carry out inner zero clearing, and request energy accumulation unit carries out inner zero clearing; According to request, carry out inner zero clearing from the energy accumulation unit.

Described sampled point counter is further stored the shunt running judgment threshold that sets in advance; When the sampling number accumulation result equals the shunt running judgment threshold, judge that the sampling number accumulation result overflows.

Described anti-shunt running circuit further comprises: sample count exclusive disjunction unit, be used for when the spill over that receives from the sampled point counter, perhaps when the output that receives from the energy accumulation unit, perhaps when receiving systematic reset signal, request sampled point counter carries out inner zero clearing;

Described sampled point counter further when the sampling number accumulation result overflows, sends spill over to described sample count exclusive disjunction unit; According to request, carry out inner zero clearing from sample count exclusive disjunction unit;

Described energy accumulation unit is further when the energy accumulation result is overflowed, to the output pulse of sample count exclusive disjunction unit.

Described anti-shunt running circuit further comprises: energy accumulation exclusive disjunction unit, be used for when the spill over that receives from the sampled point counter, and perhaps when receiving systematic reset signal, request energy accumulation unit carries out inner zero clearing;

Described sampled point counter is further when the sampling number accumulation result overflows, to energy accumulation exclusive disjunction unit output spill over;

Described energy accumulation unit further according to the request from energy accumulation exclusive disjunction unit, carries out inner zero clearing.

Described circuit further comprises: first comparer, counter and second comparer;

Described first comparer under the control of synchronizing signal, is sampled to the electric current in the ic for energy metering; The current sample result is compared with the threshold value that sets in advance, and in the current sample result during greater than threshold value, to the request of counter output counting, otherwise request counter carries out inner zero clearing;

Described counter under the control of synchronizing signal, carries out accumulated counts to the counting request from first comparer, and accumulation result is exported to second comparer; According to carrying out inner zero clearing from the request of first comparer or second comparer;

Described second comparer, under the control of synchronizing signal, to compare with the threshold value that sets in advance from the accumulation result of counter, and at accumulation result during greater than threshold value, to described sample count exclusive disjunction unit requests the sampled point counter is carried out inner zero clearing, and request counter carries out inner zero clearing;

Described sample count exclusive disjunction unit asks described sampled point counter to carry out inner zero clearing further according to the request of second comparer.

Described energy accumulation unit is active power energy accumulation unit;

Described circuit further comprises: reactive power energy accumulation unit is used under the control of synchronizing signal the reactive power in the ic for energy metering being sampled, and sampled result is carried out energy accumulation; When the energy accumulation result of reactive power is overflowed, in sample count exclusive disjunction unit and ic for energy metering, be used to measure the metering units output reactive power calibration pulse of reactive power; According to request, carry out inner zero clearing from energy accumulation exclusive disjunction unit;

Described sample count exclusive disjunction unit further when receiving the reactive power calibration pulse of reactive power energy accumulation unit output, asks described sampled point counter to carry out inner zero clearing;

Described energy accumulation exclusive disjunction unit further when the spill over that receives from the sampled point counter, perhaps when receiving systematic reset signal, asks described reactive power energy accumulation unit to carry out inner zero clearing.

Based on another above-mentioned fundamental purpose, the invention provides the anti-shunt running circuit in a kind of electric energy metrical, comprising: energy accumulation unit, sampled point counter and judging unit;

Sample to the power input in the ic for energy metering under the control of synchronizing signal in described energy accumulation unit, and sampled result is carried out energy accumulation; The result offers judging unit with energy accumulation; According to request, carry out inner zero clearing from the sampled point counter;

Described sampled point counter adds up to the sampling number of power input under the control of described synchronizing signal; When accumulation result overflows, carry out inner zero clearing, and ask the energy accumulation unit to carry out inner zero clearing, the request judging unit is judged;

Described judging unit receives the output result who is used for electric energy metrical in the ic for energy metering; Request according to sample counter, will from energy add up the energy accumulation result of unit with in advance the storage threshold value compare, and in the energy accumulation result during, the current described output result who receives is exported to metering units in the ic for energy metering more than or equal to threshold value.

Described judging unit comprises: absolute value element, threshold cell, comparer and output control unit;

Further when the sampling number accumulation result overflowed, the request comparer compared described sampled point counter;

Described energy accumulation unit further offers absolute value element with the energy accumulation result;

Described absolute value element is calculated the energy accumulation absolute value from the energy accumulation result of energy accumulation unit, and the energy accumulation absolute value that calculates is sent to comparer;

Described threshold cell is stored predefined shunt running judgment threshold, and offers comparer;

Described comparer receives from the energy accumulation absolute value of absolute value element with from the shunt running judgment threshold of threshold cell; According to the request of sampled point counter, energy accumulation absolute value and shunt running judgment threshold are compared, at the energy accumulation absolute value during, send to output control unit and to allow output signal more than or equal to the shunt running judgment threshold;

Described output control unit receives the calibration pulse in the ic for energy metering; According to permission output signal, the current calibration pulse signal that receives is sent to metering units in the ic for energy metering from comparer.

Described judging unit comprises: absolute value element, threshold cell, comparer, output control unit and shift unit;

Further when the sampling number accumulation result overflowed, the request comparer compared described sampled point counter;

Described energy accumulation unit further offers shift unit with the energy accumulation result;

Described shift unit carries out shifting processing to the energy accumulation result from the energy accumulation unit, obtains average power; Average power is offered absolute value element;

Described absolute value element is calculated the absolute value from the average power of shift unit, and the average power absolute value that calculates is sent to comparer;

Described threshold cell is stored predefined shunt running judgment threshold, and offers comparer;

Described comparer receives from the average power absolute value of absolute value element with from the shunt running judgment threshold of threshold cell; According to the request of sampled point counter, average power absolute value and shunt running judgment threshold are compared, at the average power absolute value during, send to output control unit and to allow output signal more than or equal to the shunt running judgment threshold;

Described output control unit receives from the calibration pulse in the ic for energy metering; According to permission output signal, the current calibration pulse signal that receives is sent to metering units in the ic for energy metering from comparer.

Described shift unit is the bit wide of described sampled point counter to carry out the figure place of shifting processing from the energy accumulation result of energy accumulation unit.

The bit wide of described energy accumulation unit is the bit wide of sampled point counter and the bit wide sum of power input.

Described counter is a status comparator;

Described judging unit further comprises: first comparer, counter, second comparer and exclusive disjunction unit;

Described first comparer under the control of synchronizing signal, is sampled to the electric current in the ic for energy metering; The current sample result is compared with the threshold value that sets in advance, and in the current sample result during greater than threshold value, to the request of counter output counting, otherwise request counter carries out inner zero clearing;

Described counter under the control of synchronizing signal, carries out accumulated counts to the counting request from first comparer, and accumulation result is exported to second comparer; According to carrying out inner zero clearing from the request of first comparer or second comparer;

Described second comparer under the control of synchronizing signal, will compare from the accumulation result of counter and the threshold value that sets in advance, and at accumulation result during greater than threshold value, output allows output signal to the exclusive disjunction unit, and request counter carries out inner zero clearing;

Described output control unit will be exported to from the permission output signal of described second comparer or described status comparator in described exclusive disjunction unit;

Described output control unit is further according to from the permission output signal of described exclusive disjunction unit, and the current calibration pulse signal that receives is sent to metering units in the ic for energy metering.

Another fundamental purpose based on above-mentioned the invention provides a kind of energy meter anti-creeping, may further comprise the steps:

The energy accumulation unit carries out energy accumulation to the sampled result of power input, and by the sampled point counter sampling number is added up; When the sampling number accumulation result overflows, energy accumulation unit and sampled point counter are carried out inner zero clearing; When the energy accumulation result is overflowed, carry out electric energy metrical.

Described energy accumulation unit carries out energy accumulation to the sampled result of power input: the energy accumulation unit is under the control of synchronizing signal, the power input that receives is sampled, the sampled point counter is carried out inner zero clearing, and and sampled result carried out energy accumulation;

Described sampled point counter is accumulated as sampling number: the sampled point counter adds up to sampling number under the control of synchronizing signal.

Before described sampling number accumulation result overflows, further comprise: the shunt running judgment threshold of sampling number accumulation result with storage in advance compared, if the shunt running judgment threshold that the sampling number accumulation result equals to store in advance determines that then the sampling number accumulation result overflows.

Described energy accumulation result further comprises after overflowing: sampled point counter and energy accumulation unit carry out inner zero clearing.

Described carrying out further comprises before the electric energy metrical:

Electric current in the ic for energy metering is sampled, and the current sample result who surpasses the current threshold that sets in advance is continuously counted; If this count results surpasses predefined number of times, then the sampled point counter is carried out inner zero clearing.

Described carrying out further comprises before the electric energy metrical:

Reactive power in the ic for energy metering is carried out energy accumulation, and when the energy accumulation result of reactive power reaches pre-set threshold, the sampled point counter is carried out inner zero clearing.

Also fundamental purpose based on above-mentioned the invention provides a kind of energy meter anti-creeping, may further comprise the steps:

The energy accumulation unit carries out energy accumulation to the sampled result of power input, and by the sampled point counter sampling number is added up; When the sampling number accumulation result overflows, the energy accumulation result is compared with the threshold value that sets in advance, and carry out electric energy metrical during more than or equal to threshold value in the energy accumulation result.

Described with energy accumulation result and the threshold value that sets in advance compare into:

When the sampling number accumulation result overflowed, the merchant of calculating energy accumulation result and sampling number obtained average power, and asked the absolute value of average power, then the absolute value of described average power and the shunt running judgment threshold that sets in advance was compared.

Described with energy accumulation result and the threshold value that sets in advance compare into:

When the sampling number accumulation result overflows, ask energy accumulation result's average absolute, this mean value and the shunt running judgment threshold that sets in advance are being compared.

Described when the energy accumulation result is compared with the threshold value that sets in advance, further comprise: sampled point counter and energy accumulation unit carry out inner zero clearing.

Described carrying out further comprises before the electric energy metrical:

Electric current in the ic for energy metering is sampled, and the current sample result who surpasses the current threshold that sets in advance is continuously counted; If this count results surpasses predefined number of times, then carry out the described electric energy metrical that carries out.

As seen from the above technical solution, the present invention carries out energy accumulation by the energy accumulation unit to the sampled result of power input, and sampling number is added up by the sampled point counter, energy accumulation after the sampling has been eliminated the ripple of power input, be equivalent to power input has been carried out low-pass filtering, when energy accumulation result or sampling number accumulation result overflow, carry out electric energy metrical according to the energy accumulation result, thereby improved the control accuracy and the reliability of anti-shunt running.

The present invention only increases a sampled point counter in existing ic for energy metering, promptly realized the anti-shunt running of electric energy metrical, and realizes that simply hardware cost is low; The present invention is also based on preventing that shunt running definition and average power have realized the anti-shunt running of electric energy metrical, have accurately judged the shunt running state in the electric energy metrical; Simultaneously, the present invention has solved in the electric energy metrical also based on the definition of current effective value, when electric current and voltage phase place angle is very little, and the problem that active power is left in the basket and measures.

Description of drawings

Fig. 1 a is the structural drawing of anti-shunt running circuit 1 in the prior art.

Fig. 1 b is the structural drawing of anti-shunt running circuit 2 in the prior art.

Fig. 2 is the ripple synoptic diagram of power input.

Fig. 3 is the structural representation of ic for energy metering.

Fig. 4 is the exemplary block diagram of the anti-shunt running circuit in a kind of electric energy metrical among the present invention.

Fig. 5 is the exemplary block diagram of the anti-shunt running circuit in the another kind of electric energy metrical among the present invention.

Fig. 6 a is the structural drawing of anti-shunt running circuit 1 in the circuit embodiments one of the present invention.

Fig. 6 b is the structural drawing of anti-shunt running circuit 2 in the circuit embodiments one of the present invention.

Fig. 7 is the structural drawing of anti-shunt running circuit in the circuit embodiments two of the present invention.

Fig. 8 is the structural drawing of anti-shunt running circuit in the circuit embodiments three of the present invention.

Fig. 9 is the exemplary process diagram of a kind of energy meter anti-creeping among the present invention.

Figure 10 is the exemplary process diagram of another kind of energy meter anti-creeping among the present invention.

Figure 11 is the process flow diagram of creeping prevention method among the inventive method embodiment one.

Figure 12 is the process flow diagram of creeping prevention method among the inventive method embodiment two.

Figure 13 is the process flow diagram of creeping prevention method among the inventive method embodiment three.

Embodiment

For making purpose of the present invention, technical scheme and advantage clearer, below with reference to the accompanying drawing embodiment that develops simultaneously, the present invention is described in more detail.

At first, anti-shunt running circuit of the present invention is described.

Anti-shunt running circuit of the present invention can be used as a module and adds in the ic for energy metering, realizes the anti-shunt running of electric energy metrical.

Fig. 3 is the structural representation of ic for energy metering.As shown in Figure 3, generally, ic for energy metering comprises: AD conversion unit 301 and AD conversion unit 302, filtering extraction unit 303 and filtering extraction unit 304, multiplier 305, low-pass filter 306, energy accumulation unit 307 and metering units 308.

AD conversion unit 301 and AD conversion unit 302 are converted to current analog signal and voltage analog signal the digital signal of 1 bit respectively, and the current digital signal after will changing and voltage digital signal are exported to filtering extraction unit 303 and filtering extraction unit 304 respectively.

Filtering extraction unit 303 and filtering extraction unit 304 are converted to the voltage digital signal of the current digital signal of 1 bit and 1 bit the parallel current digital signal and the parallel voltage digital signal of a plurality of bits more respectively, and parallel current digital signal and parallel voltage digital signal are exported to multiplier 305.

Multiplier 305 calculates the product of parallel current digital signal and parallel voltage digital signal, obtains instantaneous power, and exports to low-pass filter 306.

306 pairs of instantaneous powers from multiplier of low-pass filter are carried out low-pass filtering, and filtered instantaneous power is exported to energy accumulation unit 307 as power input.

Energy accumulation unit 307 receives power input, and the numerical value of power input is added up, and promptly energy adds up, when accumulation result overflows, by number conversion frequently, the output pulse is given metering units 308 and is carried out inner zero clearing, and this moment, the pulse of output can be called the calibration pulse.Metering units 308 is the calibration step-by-step counting to receiving again, realizes electric energy metrical.

Wherein, metering units 308 also can be the functional unit outside the ic for energy metering, for example measuring apparatus in the ammeter.

In the above-mentioned ic for energy metering, each unit can carry out inter-process and mutual information interaction under the control of synchronizing signal; This synchronizing signal can be from the synchronous device outside the ic for energy metering, and for example crystal oscillator also can be produced by any one unit in the ic for energy metering, for example filtering extraction unit 303, multiplier 305 or low-pass filter 306, and send to other unit; Each unit in the above-mentioned ic for energy metering also can all carry out reset operation when receiving systematic reset signal; AD conversion unit 301 and filtering extraction unit 303, AD conversion unit 302 and filtering extraction unit 304 also can be respectively two directly AD conversion unit of output parallel signal.

Also can not comprise low-pass filter 306 in the above-mentioned ic for energy metering, at this moment, multiplier 305 offers energy accumulation unit 307 directly with the power input of instantaneous power as energy accumulation unit 307.

Fig. 4 is the exemplary block diagram of a kind of anti-shunt running circuit among the present invention.As shown in Figure 4, the anti-shunt running circuit in a kind of electric energy metrical among the present invention comprises: sampled point counter 401 and energy accumulation unit 402.

Energy accumulation unit 402 is used under the control of synchronizing signal the power input in the ic for energy metering being sampled, and sampled result is carried out energy accumulation; When the energy accumulation result was overflowed, request sampled point counter 401 carried out inner zero clearing, and the request metering units carries out electric energy metrical; According to the request of sampled point counter 401, carry out inner zero clearing;

Sampled point counter 401 is used under the control of synchronizing signal, and the sampling number of power input is added up; When the sampling number accumulation result overflows, carry out inner zero clearing, and request energy accumulation unit 402 carries out inner zero clearing; According to request, carry out inner zero clearing from energy accumulation unit 402.

Wherein, synchronizing signal can be the synchronizing signal in the ic for energy metering as shown in Figure 3; Metering units is the metering units 308 in as shown in Figure 3 the ic for energy metering.

Above-mentioned anti-shunt running circuit is based on sampling number and realizes anti-shunt running, store the higher limit that adds up in the sampled point counter 401 in advance, if the energy accumulation result is not overflowed in the sampling number of higher limit that adds up, judge that then this energy accumulation result is the energy accumulation result under the shunt running state, and to 402 zero clearings of energy accumulation unit.

In the above-mentioned anti-shunt running circuit, energy accumulation unit 402 can be identical with the energy accumulation unit 307 in as shown in Figure 3 the ic for energy metering.Therefore, when realizing that based on anti-shunt running circuit as shown in Figure 4 electric energy metrical is prevented shunt running, only need in ic for energy metering, to add sampled point counter 401 and get final product.

Fig. 5 is the exemplary block diagram of another kind of anti-shunt running circuit among the present invention.As shown in Figure 5, the anti-shunt running circuit of the another kind among the present invention comprises: sampled point counter 501, energy accumulation unit 502 and judging unit 503.

Energy accumulation unit 502 is used under the control of synchronizing signal power input being sampled, and sampled result is carried out energy accumulation; The energy accumulation result is offered judging unit 503; According to request, carry out inner zero clearing from sampled point counter 501;

Sampled point counter 501 is used under the control of synchronizing signal, and the sampling number of the power input in the ic for energy metering is added up; When the sampling number accumulation result overflows, carry out inner zero clearing, and ask energy accumulation unit 502 to carry out inner zero clearing, request judging unit 503 is judged;

Judging unit 503 is used for receiving the output result that ic for energy metering is used for electric energy metrical; According to request from sample counter 501, will from energy add up the energy accumulation result of unit 502 with in advance the storage threshold value compare, and in the energy accumulation result during, the current output result who receives is exported to metering units in the ic for energy metering more than or equal to threshold value.

Wherein, synchronizing signal can be the synchronizing signal in the ic for energy metering as shown in Figure 3; The output result who is used for electric energy metrical that judging unit 503 receives is the calibration pulse of as shown in Figure 3 energy accumulation unit 307 output; In the energy accumulation result during more than or equal to threshold value, judging unit 503 is exported to metering units 308 in as shown in Figure 3 the ic for energy metering with the current calibration pulse that receives.

In the above-mentioned anti-shunt running circuit, energy accumulation unit 502 is with respect to the difference of the energy accumulation unit 307 in the ic for energy metering shown in Figure 3: the threshold value that the energy accumulation result of energy accumulation unit 502 outputs only is used for storing in advance with judging unit 503 is compared, thereby realize shunt running state in the ic for energy metering is judged, rather than when the energy accumulation result is overflowed, count conversion frequently, output is used for the pulse of electric energy metrical.

Above-mentioned Fig. 4 and anti-shunt running circuit structure shown in Figure 5 are exemplary configurations.Below, in conjunction with specific embodiments, the anti-shunt running circuit among the present invention is elaborated.

Circuit embodiments one

Comprise 2 kinds of anti-shunt running circuit in the present embodiment, promptly anti-shunt running circuit 1 and anti-shunt running circuit 2 all are based on exemplary circuit configuration as shown in Figure 4 and adopt the principle of sampled point method to realize.

Anti-shunt running circuit 1 has increased the interlock circuit structure that is used to judge starting state on circuit structure as shown in Figure 4, so that ic for energy metering can not ignored metering to very little active power when keeping higher control accuracy and reliability; Anti-shunt running circuit 2 has increased the energy accumulation unit that is used to measure reactive power on circuit structure as shown in Figure 4, so that ic for energy metering can not ignored metering to very little active power when keeping higher control accuracy and reliability.

Fig. 6 a is the structural drawing of anti-shunt running circuit 1 in the circuit embodiments one of the present invention.Shown in Fig. 6 a, the anti-shunt running circuit in the present embodiment comprises: sampled point counter 601, energy accumulation unit 602, exclusive disjunction unit 603, exclusive disjunction unit 604, comparer 605, counter 606 and comparer 607.

Sampled point counter 601 is used to store the shunt running judgment threshold that precomputes; According to the synchronizing signal that receives, the sampling number of power input is added up; When the sampling number accumulation result equaled the shunt running judgment threshold, to exclusive disjunction unit 603 and exclusive disjunction unit 604 output spill overs, request was to self carrying out inner zero clearing, asking energy accumulation unit 602 to carry out inner zero clearing respectively; According to reset signal, carry out inner zero clearing from exclusive disjunction unit 603.

Energy accumulation unit 602 is used for the power input in the ic for energy metering that receives being sampled, and sampled result being carried out energy accumulation according to the synchronizing signal that receives; When the energy accumulation result is overflowed, to exclusive disjunction unit 603 and the pulse of metering units output calibration; According to reset signal, carry out inner zero clearing from exclusive disjunction unit 604.

Wherein, the power input that energy accumulation unit 602 receives is from low-pass filter in the ic for energy metering as shown in Figure 3 306 or multiplier 305; Metering units is the metering units 308 in as shown in Figure 3 the ic for energy metering, and metering units 308 measures according to the calibration pulse that receives.

Exclusive disjunction unit 603, it is sample count exclusive disjunction unit, be used for when the spill over that receives from sampled point counter 601, perhaps when the calibration pulse that receives from energy accumulation unit 602, perhaps when receiving the low level signal of exporting from comparer 607, again or when receiving systematic reset signal, to sampled point counter 601 output reset signals, request sampled point counter 601 carries out inner zero clearing.

Exclusive disjunction unit 604, be the energy exclusive disjunction unit that adds up, be used for when the spill over that receives from sampled point counter 601, perhaps when receiving systematic reset signal, to energy accumulation unit 602 output reset signals, request energy accumulation unit 602 carries out inner zero clearing.

Wherein, the systematic reset signal that exclusive disjunction unit 603 and exclusive disjunction unit 604 receive, be reset signal, the anti-shunt running circuit in the present embodiment be arranged in the ic for energy metering that anti-shunt running circuit also receives this reset signal at all unit in the ic for energy metering as shown in Figure 3.

Comparer 605 is used for according to the synchronizing signal that receives the input current that receives being sampled; The sampled result of input current and the threshold value that sets in advance are compared, and at input current during greater than threshold value, to counter 606 output high level signals, otherwise, to counter 606 output low level signals.

Wherein, the input current that comparer 605 receives can be from the filtering extraction unit 303 in the ic for energy metering as shown in Figure 3.

Counter 606 is used for the high level signal from comparer 605 being carried out accumulated counts, and accumulation result being exported to comparer 607 according to the synchronizing signal that receives; Carry out inner zero clearing according to low level from comparer 605; Signal according to from comparer 607 outputs carries out inner zero clearing.

Comparer 607, be used for according to the synchronizing signal that receives, to compare with the threshold value that sets in advance from the accumulation result of counter 606, and at accumulation result during greater than threshold value, to signal of exclusive disjunction unit 603 sum counters, 606 outputs, high level signal for example, otherwise, to exclusive disjunction unit 603 sum counters, 606 output low level signals.

In the above-mentioned anti-shunt running circuit, the circuit structure that comparer 605, counter 606 and comparer 607 combine can be set to a functional unit, starting state judging unit for example, mainly acting as of this circuit structure: if the individual sampled result to input current of N continuous is inferior all above M, judge that then current electric energy metrical is in starting state, promptly the electric energy metrical result is the electric energy metrical result to active power.Wherein, the threshold value in the comparer 605 is N, and the threshold value in the comparer 607 is M, and the concrete numerical value of M and N can be set arbitrarily according to the actual conditions in the electric energy metrical.At this moment, even if active power owing to current/voltage phase place angle approaching ± 90 the degree become very little, still can be measured.

In actual applications, may be approaching owing to current/voltage phase place angle ± power input that 90 degree make energy accumulation unit 602 receive is very little, and within the sampling number of sampled point counter 601 regulations, the accumulation result of energy accumulation unit 602 may not can overflow, but this accumulation result should be measured, therefore, and when judging current state and be starting state, only sampled point counter 601 is carried out inner zero clearing, and keep the energy accumulation result in the energy accumulation unit 602.

More than be explanation to anti-shunt running circuit 1 in the present embodiment, below, the anti-shunt running circuit 2 in the present embodiment is elaborated.

Anti-shunt running circuit 2 in the present embodiment has increased the energy accumulation unit 608 that is used to measure reactive power on circuit structure as shown in Figure 4.

In the practical application, in ic for energy metering as shown in Figure 3, can also comprise the device that is used to calculate reactive power, this device receives the current digital signal and the voltage digital signal of filtering extraction unit 303 and 304 outputs of filtering extraction unit, the line correlation computing of going forward side by side, the output reactive power.Energy accumulation unit 608 in the anti-shunt running circuit 2 in the present embodiment, with reactive power of this device output as power input.In ic for energy metering as shown in Figure 3, can also comprise the metering units that is used to measure reactive power, the energy accumulation unit 608 in the present embodiment is to the calibration pulse of this metering units output reactive power.

Fig. 6 b is the structural drawing of anti-shunt running circuit 2 in the circuit embodiments one of the present invention.As shown in Figure 6, the anti-shunt running circuit in the present embodiment comprises: sampled point counter 601, energy accumulation unit 602, exclusive disjunction unit 603, exclusive disjunction unit 604 and energy accumulation unit 608.

Sampled point counter 601 is used to store the shunt running judgment threshold that precomputes; According to the synchronizing signal that receives, the sampling number of power input is added up; When the sampling number accumulation result equaled the shunt running judgment threshold, to exclusive disjunction unit 603 and exclusive disjunction unit 604 output spill overs, request was to self carrying out inner zero clearing, asking energy accumulation unit 602 to carry out inner zero clearing respectively; According to reset signal, carry out inner zero clearing from exclusive disjunction unit 603.

Energy accumulation unit 602 is used for the power input in the ic for energy metering that receives being sampled, and sampled result being carried out energy accumulation according to the synchronizing signal that receives; When the energy accumulation result is overflowed, to exclusive disjunction unit 603 and the pulse of metering units output calibration; According to reset signal, carry out inner zero clearing from exclusive disjunction unit 604.

Wherein, the power input that energy accumulation unit 602 receives is from low-pass filter in the ic for energy metering as shown in Figure 3 306 or multiplier 305; Metering units is the metering units 308 in as shown in Figure 3 the ic for energy metering, and metering units 308 measures according to the calibration pulse that receives.

Exclusive disjunction unit 603, it is sample count exclusive disjunction unit, be used for when the spill over that receives from sampled point counter 601, perhaps when the calibration pulse that receives from energy accumulation unit 602, perhaps when the calibration pulse that receives from energy accumulation unit 608, again or when receiving systematic reset signal, to sampled point counter 601 output reset signals, request sampled point counter 601 carries out inner zero clearing.

Exclusive disjunction unit 604, be the energy exclusive disjunction unit that adds up, be used for when the spill over that receives from sampled point counter 601, perhaps when receiving systematic reset signal, to energy accumulation unit 602 output reset signals, request energy accumulation unit 602 carries out inner zero clearing.

Wherein, the systematic reset signal that exclusive disjunction unit 603 and exclusive disjunction unit 604 receive, be reset signal, the anti-shunt running circuit in the present embodiment be arranged in the ic for energy metering that anti-shunt running circuit also receives this reset signal at all unit in the ic for energy metering as shown in Figure 3.

Energy accumulation unit 608 is used for the reactive power that receives being sampled, and sampled result being carried out energy accumulation according to the synchronizing signal that receives; When the energy accumulation result is overflowed, to exclusive disjunction unit 603 and the metering units output reactive power calibration pulse that is used to measure reactive power; According to reset signal, carry out inner zero clearing from exclusive disjunction unit 604.

In the electric energy metrical process, may be approaching owing to current/voltage phase place angle ± power input that 90 degree make energy accumulation unit 602 receive is very little, and within the sampling number of sampled point counter 601 regulations, the accumulation result of energy accumulation unit 602 may not can overflow, but this accumulation result should be measured.Therefore,, when promptly meritorious reactive power is all less, just be judged to be the shunt running state within the regulation sampling number, the energy accumulation result is carried out zero clearing if energy accumulation unit 602 and energy accumulation unit 608 all do not overflow; Otherwise, if only energy accumulation unit 608 overflows, promptly reactive power is big, active power is less, judges that still current state is a starting state, to sampled point counter 601 and 608 zero clearings of energy accumulation unit, and the energy accumulation result in the reservation energy accumulation unit 602.

The shunt running judgment threshold of sampled point counter 601 storages is the numerical value that calculates according to the GB regulation in the present embodiment, for example, and the product of the minimum time of calculating GB regulation and the sample frequency of anti-shunt running circuit.

Wherein, the computation process of the minimum time of GB regulation can be expressed as:

For 1 grade of electric power meter: $\mathrm{\&Delta;t}=\frac{600\&times;{10}^6}{k*m*U_n*I_{\max }}\left[\min \right]$

For 2 grades of electric power meters: $\mathrm{\&Delta;t}=\frac{480\&times;{10}^6}{k*m*U_n*I_{\max }}\left[\min \right]$

Wherein, Δ t represents the shortest time; K represents umber of pulse/kilowatt-hour (imp/kWh) that the instrument output unit sends; M represents the measuring unit number; U _nThe expression reference voltage; I _MaxThe expression maximum current.

The meaning of shortest time is: the calibration pulse of being sent out in this shortest time should be more than 1, and the open circuit of the current circuit in the ic for energy metering, and voltage circuit institute making alive is 115% of a reference voltage.

Hence one can see that, the acting as of shunt running judgment threshold in the present embodiment: anti-shunt running circuit is within the sampling number of this prescribed threshold, if do not send the calibration pulse, the energy accumulation result who then judges the acquisition 602 this moment of energy accumulation unit is the energy accumulation result under the shunt running state, does not need to measure.

In the anti-shunt running circuit of present embodiment, also can not store the shunt running judgment threshold that calculates according to the GB regulation in the sampled point counter 601, but the bit wide of sampled point counter 601 is set to and shunt running judgment threshold value corresponding; Exclusive disjunction unit 603 and exclusive disjunction unit 604 also can be set to the computing module of sampled point counter 601 and 602 inside, energy accumulation unit respectively.

The anti-shunt running circuit of present embodiment, realize simple, hardware cost is low, only need in existing ic for energy metering, to increase the anti-shunt running that several simple module can realize degree of precision and higher reliability, and this circuit has also solved current/voltage phase place angle when approaching ± 90 spend, the be left in the basket problem of metering of active power.

Circuit embodiments two

Anti-shunt running circuit in the present embodiment is based on exemplary circuit configuration as shown in Figure 5 and adopts the principle of ENERGY METHOD to realize.

Fig. 7 is the structural drawing of anti-shunt running circuit in the circuit embodiments two of the present invention.As shown in Figure 7, the anti-shunt running circuit in the present embodiment comprises: sampled point counter 701, energy accumulation unit 702, absolute value element 703, threshold cell 704, comparer 705, output control unit 706, comparer 707, counter 708, comparer 709 and exclusive disjunction unit 710.

Sampled point counter 701 for bit wide is the counter of N bit, is used for according to the synchronizing signal that receives, and the sampling number of power input is added up; When the sampling number accumulation result overflows, carry out inner zero clearing, and respectively to energy accumulation unit 702 and comparer 705 output spill overs, request energy accumulation unit 702 carries out inner zero clearing, request comparer 705 compares.Compare with the sampled point counter 601 in the circuit embodiments one, the difference of sampled point counter 701 is that it mainly act as: the cycle that the control shunt running is judged.

Energy accumulation unit 702, its bit wide be the bit number of power input add the N bit and, be used for the power input in the ic for energy metering that receives being sampled, and sampled result being carried out energy accumulation according to the synchronizing signal that receives; The energy accumulation result is offered absolute value element 703; According to spill over, carry out inner zero clearing from sampled point counter 701.

Wherein, the power input that energy accumulation unit 702 receives is from low-pass filter in the ic for energy metering as shown in Figure 3 306 or multiplier 305.

Absolute value element 703 is used to calculate the energy accumulation absolute value from the energy accumulation result of energy accumulation unit 702, and the energy accumulation absolute value that calculates is exported to comparer 705.

Threshold cell 704 is used to store predefined shunt running judgment threshold, and offers comparer 705.

Wherein, the shunt running judgment threshold in the present embodiment can be different with the shunt running judgment threshold in the circuit embodiments one, but set arbitrarily according to the actual conditions of ic for energy metering, stipulate in the corresponding span but should be in GB.

Comparer 705 is used to receive from the energy accumulation absolute value of absolute value element 703 with from the shunt running judgment threshold of threshold cell 704; According to spill over from sampled point counter 701, energy accumulation absolute value and shunt running judgment threshold are compared, at the energy accumulation absolute value during more than or equal to the shunt running judgment threshold, to signal of exclusive disjunction unit 710 outputs, for example high level pulse allows output control unit 706 to outside output, otherwise, to exclusive disjunction unit 710 output low level signals, forbid that output control unit 706 exports to the outside.

Comparer 707 is used for according to the synchronizing signal that receives the input current that receives being sampled; The sampled result of input current and the threshold value that sets in advance are compared, and at input current during greater than threshold value, to counter 708 output high level signals, otherwise, to counter 708 output low level signals.

Wherein, the input current that comparer 707 receives can be from the filtering extraction unit 303 in the ic for energy metering as shown in Figure 3.

Counter 708 is used for the high level signal from comparer 707 being carried out accumulated counts, and accumulation result being exported to comparer 709 according to the synchronizing signal that receives; Carry out inner zero clearing according to low level signal from comparer 707; Signal according to from comparer 709 outputs carries out inner zero clearing.

Comparer 709 is used for according to the synchronizing signal that receives, and will compare with the threshold value that sets in advance from the accumulation result of counter 708; During greater than threshold value, to signal of exclusive disjunction unit 710 sum counters, 708 outputs, for example high level pulse allows output control unit 706 to carry out inner zero clearing to outside output and request counter 708 at accumulation result.Comparer 709 can also be from the accumulation result of counter 708 during less than threshold value, to exclusive disjunction unit 710 output low level signals, forbids that output control unit 706 exports to the outside.

Exclusive disjunction unit 710 is used for receiving from comparer 705 or during from the signal of comparer 709 output, request output control unit 706 is exported to the outside.

Output control unit 706 is used for receiving the calibration pulse from the energy accumulation unit 307 of as shown in Figure 3 ic for energy metering; According to request, the current calibration pulse signal that receives is exported to metering units from exclusive disjunction unit 710.

Wherein, metering units is the metering units 308 in as shown in Figure 3 the ic for energy metering, and metering units 308 measures according to the calibration pulse that receives.

In the above-mentioned anti-shunt running circuit, the circuit structure significant feature that sampled point counter 701, energy accumulation unit 702, absolute value element 703, threshold cell 704 and comparer 705 are formed is: not enough within a certain period of time certain energy, just must not measure the 307 output calibration pulses of the energy accumulation unit in the ic for energy metering as shown in Figure 3.

In the above-mentioned anti-shunt running circuit, mainly acting as of comparer 707, counter 708 and comparer 709: if the individual sampled result to input current of N continuous is inferior all above M, judge that then current electric energy metrical is in starting state, promptly the electric energy metrical result is the electric energy metrical result to active power.Wherein, the threshold value in the comparer 707 is N, and the threshold value in the comparer 709 is M, and the concrete numerical value of M and N can be set arbitrarily according to the actual conditions in the electric energy metrical.At this moment, even if active power owing to current/voltage phase place angle approaching ± 90 the degree become very little, still can be measured.

Therefore, any one in comparer 705 and comparer 709 when judging current state and being starting state, just allows energy accumulation unit 307 in the ic for energy metering as shown in Figure 3 to metering units 308 output calibration pulses.

In the anti-shunt running circuit of present embodiment, also can be with absolute value element 703, threshold cell 704, comparer 705, output control unit 706, comparer 707, counter 708, comparer 709 and exclusive disjunction unit 710 are set to a functional unit, i.e. judging unit 503 in the anti-shunt running circuit as shown in Figure 5.

In the present embodiment, sampled point counter 701 and energy accumulation unit 702 also can judge whether accumulation result overflows respectively according to the threshold value of storage inside, rather than judge according to the bit wide of self whether accumulation result overflows.

The anti-shunt running circuit of present embodiment is used for judging the anti-shunt running state of ic for energy metering, its principle of work mainly is based on anti-shunt running and defines and realize, i.e. " in the certain hour; certain inadequately energy; just must not send pulse ", and this circuit has also solved current/voltage phase place angle when approaching ± 90 spend, the be left in the basket problem of metering of active power.Therefore, the anti-shunt running circuit in the present embodiment is accurate and reliable to the judgement of shunt running state.

Circuit embodiments three

Anti-shunt running circuit in the present embodiment is based on exemplary circuit configuration as shown in Figure 5 and adopts the principle of average power method to realize.

Fig. 8 is the structural drawing of anti-shunt running circuit in the circuit embodiments three of the present invention.As shown in Figure 8, the anti-shunt running circuit among the present invention comprises: sampled point counter 801, energy accumulation unit 802, absolute value element 803, threshold cell 804, comparer 805, output control unit 806, shift unit 807, comparer 808, counter 809, comparer 810 and exclusive disjunction unit 811.

Sampled point counter 801 for bit wide is the counter of N bit, is used for according to the synchronizing signal that receives, and the sampling number of power input is added up; When the sampling number accumulation result overflows, carry out inner zero clearing, and respectively to energy accumulation unit 802 and comparer 805 output spill overs, request energy accumulation unit 802 carries out inner zero clearing, request comparer 805 compares.Compare with the sampled point counter 601 in the circuit embodiments one, the difference of sampled point counter 801 is that it mainly act as: the cycle that the control shunt running is judged.

Energy accumulation unit 802, its bit wide be the bit number of power input add the N bit and, be used for the power input in the ic for energy metering that receives being sampled, and sampled result being carried out energy accumulation according to the synchronizing signal that receives; The energy accumulation result is offered shift unit 807; According to spill over, carry out inner zero clearing from sampled point counter 801.

Wherein, the power input that energy accumulation unit 802 receives is from low-pass filter in the ic for energy metering as shown in Figure 3 306 or multiplier 305.

Shift unit 807 is used for the energy accumulation result from energy accumulation unit 802 is carried out shifting processing, and the N bit that promptly moves to right obtains average power; Energy accumulation result's mean value is offered absolute value element 803.

Wherein, with the energy accumulation result N bit that moves to right, be equivalent to the merchant of calculating energy accumulation result and sampling number, this sampling number is the higher limit of sampled point counter 801.

Absolute value element 803 is used to calculate the absolute value of the average power of shift unit 807, and the average power absolute value that calculates is exported to comparer 805.

Threshold cell 804 is used to store predefined shunt running judgment threshold, and offers comparer 805.

Wherein, the shunt running judgment threshold in the present embodiment can be different with the shunt running judgment threshold in the circuit embodiments one, but set arbitrarily according to the actual conditions of ic for energy metering, stipulate in the corresponding span but should be in GB.

Comparer 805 is used to receive from the average power of absolute value element 803 with from the shunt running judgment threshold of threshold cell 804; According to spill over from sampled point counter 801, average power absolute value and shunt running judgment threshold are compared, at the average power absolute value during more than or equal to the shunt running judgment threshold, to signal of exclusive disjunction unit 811 outputs, for example high level pulse allows output control unit 806 to outside output, otherwise, to exclusive disjunction unit 811 output low level signals, forbid that output control unit 806 exports to the outside.

Comparer 808 is used for according to the synchronizing signal that receives the input current that receives being sampled; The sampled result of input current and the threshold value that sets in advance are compared, and at input current during greater than threshold value, to counter 809 output high level signals, otherwise, to counter 809 output low level signals.

Wherein, the input current that comparer 808 receives can be from the filtering extraction unit 303 in the ic for energy metering as shown in Figure 3.

Counter 809 is used for the high level signal from comparer 808 being carried out accumulated counts, and accumulation result being exported to comparer 810 according to the synchronizing signal that receives; Carry out inner zero clearing according to low level signal from comparer 808; Signal according to from comparer 810 outputs carries out inner zero clearing.

Comparer 810 is used for according to the synchronizing signal that receives, and will compare with the threshold value that sets in advance from the accumulation result of counter 809; During greater than threshold value, to signal of exclusive disjunction unit 811 sum counters, 809 outputs, for example high level pulse allows output control unit 806 to carry out inner zero clearing to outside output and request counter 809 at accumulation result.Comparer 810 can also be from the accumulation result of counter 809 during less than threshold value, to exclusive disjunction unit 811 output low level signals, forbids that output control unit 806 exports to the outside.

Exclusive disjunction unit 811 is used for receiving from comparer 805 or during from the permission output signal of comparer 810 output, request output control unit 806 is exported to the outside.

Output control unit 806 is used for receiving the calibration pulse from the energy accumulation unit 307 of as shown in Figure 3 ic for energy metering; According to request, the current calibration pulse signal that receives is sent to metering units from exclusive disjunction unit 811.

Wherein, metering units is the metering units 308 in as shown in Figure 3 the ic for energy metering, and metering units 308 measures according to the calibration pulse that receives.

In the above-mentioned anti-shunt running circuit, the circuit structure significant feature that sampled point counter 801, energy accumulation unit 802, absolute value element 803, threshold cell 804, comparer 805 and shift unit 807 are formed is: not enough within a certain period of time certain energy, just must not measure the 307 output calibration pulses of the energy accumulation unit in the ic for energy metering as shown in Figure 3.

In the above-mentioned anti-shunt running circuit, mainly acting as of comparer 808, counter 809 and comparer 810: if the individual sampled result to input current of N continuous is inferior all above M, judge that then current electric energy metrical is in starting state, promptly the electric energy metrical result is the electric energy metrical result to active power.Wherein, the threshold value in the comparer 808 is N, and the threshold value in the comparer 810 is M, and the concrete numerical value of M and N can be set arbitrarily according to the actual conditions in the electric energy metrical.At this moment, even if active power owing to current/voltage phase place angle approaching ± 90 the degree become very little, still can be measured.

Therefore, any one in comparer 805 and comparer 810 when judging current state and being starting state, just allows energy accumulation unit 307 in the ic for energy metering as shown in Figure 3 to metering units 308 output calibration pulses.

In the anti-shunt running circuit of present embodiment, also can be with shift unit 807, absolute value element 803, threshold cell 804, comparer 805, output control unit 806, comparer 808, counter 809, comparer 810 and exclusive disjunction unit 811 are set to a functional unit, i.e. judging unit 503 in the anti-shunt running circuit as shown in Figure 5.

In the present embodiment, sampled point counter 801 and energy accumulation unit 802 also can judge whether accumulation result overflows respectively according to the threshold value of storage inside, rather than judge according to the bit wide of self whether accumulation result overflows.

The anti-shunt running circuit of present embodiment is used for judging the anti-shunt running state of ic for energy metering, its principle of work mainly is based on stable energy accumulation mean value as a result, promptly stable average power realizes, and this circuit has also solved current/voltage phase place angle when approaching ± 90 spend, the be left in the basket problem of metering of active power.Therefore, the anti-shunt running circuit in the present embodiment is accurate and reliable to the judgement of shunt running state.

More than be that above-mentioned four circuit embodiments by different circuit structures, have all realized the anti-shunt running of electric energy metrical to the explanation of anti-shunt running circuit among the present invention.Below, the creeping prevention method among the present invention is described.

Fig. 9 is the exemplary process diagram of a kind of energy meter anti-creeping among the present invention.As shown in Figure 9, the creeping prevention method among the present invention may further comprise the steps:

Step 901, the energy accumulation unit carries out energy accumulation to the sampled result of the power input in the ic for energy metering, and by the sampled point counter sampling number is added up;

Step 902 when the sampling number accumulation result overflows, is carried out inner zero clearing to energy accumulation unit and sampled point counter; When the energy accumulation result is overflowed, the sampled point counter is carried out inner zero clearing, and carry out electric energy metrical.

Figure 10 is the exemplary process diagram of another kind of energy meter anti-creeping among the present invention.As shown in figure 10, the creeping prevention method among the present invention may further comprise the steps:

Step 1001, the energy accumulation unit carries out energy accumulation to the sampled result of the power input in the ic for energy metering, and by the sampled point counter sampling number is added up;

Step 1002 when the sampling number accumulation result overflows, compares the energy accumulation result with the threshold value that sets in advance, and carries out electric energy metrical during more than or equal to threshold value in the energy accumulation result.

Below, in conjunction with specific embodiments, creeping prevention method of the present invention is elaborated.

Method embodiment one

Creeping prevention method in the present embodiment is based on that as shown in Figure 9 illustrative methods realizes, the creeping prevention method in the present embodiment can be called the sampled point method.

Figure 11 is the process flow diagram of creeping prevention method among the inventive method embodiment one.As shown in figure 11, creeping prevention method of the present invention may further comprise the steps:

Step 1101, in ic for energy metering, increase a sampled point counter, the output terminal of its input end with low-pass filter or multiplier linked to each other, the input end of its output terminal with the energy accumulation unit linked to each other, and in the sampled point counter, store a shunt running judgment threshold.

In this step, the shunt running judgment threshold is the numerical value that calculates according to the GB regulation, acting as of this threshold value: anti-shunt running circuit is within the sampling number of this prescribed threshold, if do not send the calibration pulse, judge that then the energy accumulation result that the energy accumulation unit obtains at this moment is the energy accumulation result under the shunt running state; Also can not store the shunt running judgment threshold that calculates according to the GB regulation in the sampled point counter, but the bit wide of sampled point counter is set to and shunt running judgment threshold value corresponding.

Step 1102, sample to the power input in the ic for energy metering in the energy accumulation unit, and sampled result is carried out energy accumulation, and the sampled point counter adds up to the sampling number of energy accumulation unit.

Wherein, the power input that the energy accumulation unit receives can be from low-pass filter in the ic for energy metering as shown in Figure 3 306 or multiplier 305; Energy accumulation unit and sampled point counter are sampled respectively, energy accumulation and sampling number counting under the control of synchronizing signal.

In this step, simultaneously in the ic for energy metering as shown in Figure 3, the electric current of filtering extraction unit 303 outputs is sampled, and the current sample result who surpasses continuously the current threshold that sets in advance counted, if this count results surpasses predefined number of times, then only the sampled point counter is carried out inner zero clearing, with this solve since current/voltage phase place angle approaching ± 90 when spending, the be left in the basket problem of metering of active power.

In this step, can also carry out energy accumulation to the reactive power in the ic for energy metering, and when the energy accumulation result of reactive power reaches pre-set threshold, be that reactive power is big, active power hour, only the sampled point counter is carried out inner zero clearing, with this solve since current/voltage phase place angle approaching ± 90 when spending, the be left in the basket problem of metering of active power.

Step 1103 judges whether the sampling number accumulation result surpasses the shunt running judgment threshold or whether the energy accumulation result overflows, if the sampling number accumulation result does not overflow less than the shunt running judgment threshold and the energy accumulation result of storage in advance, then returns step 1102; If the shunt running judgment threshold that the sampling number accumulation result equals to store in advance, then execution in step 1104; If energy accumulation is the result overflow, then execution in step 1105.

Step 1104, sampled point counter and energy accumulation unit carry out inner zero clearing, and return step 1102, begin respectively to proceed that sampling number adds up and energy accumulation.

Step 1105, sampled point counter and energy accumulation unit carry out inner zero clearing, and the calibration pulse of energy accumulation unit output is counted, and realize electric energy metrical, and return step 1102, begin respectively to proceed that sampling number adds up and energy accumulation.

In this step, can realize electric energy metrical by the metering units in the ic for energy metering as shown in Figure 3 308.

In the above-mentioned flow process, when sampled point counter and energy accumulation unit receive systematic reset signal, also carry out inner clear operation.

The creeping prevention method of present embodiment only needs to increase the anti-shunt running that a sampled point counter can be realized electric energy metrical in existing ic for energy metering.

Method embodiment two

Creeping prevention method in the present embodiment is based on that as shown in figure 10 illustrative methods realizes, the creeping prevention method in the present embodiment can be called ENERGY METHOD.

Figure 12 is the process flow diagram of creeping prevention method among the inventive method embodiment two.As shown in figure 12, creeping prevention method of the present invention may further comprise the steps:

Step 1201, sample to the power input in the ic for energy metering in the energy accumulation unit, and sampled result is carried out energy accumulation, and the sampled point counter adds up to the sampling number of power input.

In this step, energy accumulation unit and sampled point counter are sampled respectively, energy accumulation and sampling number counting under the control of synchronizing signal.

Step 1202 judges whether the sampling number accumulation result overflows, if do not overflow, then returns step 1201; If overflow, then execution in step 1203.

Above-mentioned steps 1201～step 1202 is the process in the cycle of control shunt running judgement.

Add up energy accumulation result's the absolute value of unit output of step 1203, calculating energy, sampled point counter and energy accumulation unit carry out inner zero clearing, and execution in step 1204 and step 1201.

In this step, behind the energy accumulation unit output energy accumulation result, execution in step 1204 continues the anti-shunt running flow process in the present embodiment; After sampled point counter and energy accumulation unit carried out inner zero clearing, execution in step 1201 continued the flow process that the cycle is judged in next shunt running.

Step 1204 compares energy accumulation absolute value and the shunt running judgment threshold that sets in advance, if the energy accumulation absolute value, judges then that the calibration pulse in the ic for energy metering is effective more than or equal to the shunt running judgment threshold, and execution in step 1205; If the energy accumulation absolute value, is then judged the calibration pulse in the ic for energy metering less than the shunt running judgment threshold and is the pulse of output down of shunt running state, and execution in step 1206.

Shunt running judgment threshold in this step can be different with the shunt running judgment threshold among the method embodiment one, but set arbitrarily according to the actual conditions in the electric energy metrical, stipulate in the corresponding span but should be in GB.

In execution in step 1201～step 1204, also in the ic for energy metering as shown in Figure 3, the electric current of filtering extraction unit 303 outputs is sampled, and the current sample result who surpasses continuously the current threshold that sets in advance counted, when this count results surpasses predefined number of times, also can execution in step 1206, with this solve since current/voltage phase place angle approaching ± 90 when spending, the be left in the basket problem of metering of active power.

Step 1205 is carried out accumulated counts to the calibration pulse in the ic for energy metering, realizes the electric energy metrical under the non-shunt running state, and process ends.

Step 1206, the calibration pulse signal in the ic for energy metering is invalid, will not measure, and process ends.

In the above-mentioned flow process, when sampled point counter and energy accumulation unit receive systematic reset signal, also carry out inner clear operation.

The creeping prevention method of present embodiment is used for judging the anti-shunt running state of ic for energy metering, is based on anti-shunt running and defines and realize i.e. " in the certain hour, certain inadequately energy just must not send pulse ".Therefore, the creeping prevention method in the present embodiment is accurate and reliable to the judgement of shunt running state.

Method embodiment three

Creeping prevention method in the present embodiment is based on that as shown in figure 10 illustrative methods realizes, the creeping prevention method in the present embodiment can be called the average power method.

Figure 13 is the process flow diagram of creeping prevention method among the inventive method embodiment three.As shown in figure 13, creeping prevention method of the present invention may further comprise the steps:

Step 1301, sample to the power input in the ic for energy metering in the energy accumulation unit, and sampled result is carried out energy accumulation, and the sampled point counter adds up to the sampling number of power input.

In this step, energy accumulation unit and sampled point counter are sampled respectively, energy accumulation and sampling number counting under the control of synchronizing signal.

Step 1302 judges whether the sampling number accumulation result overflows, if do not overflow, then returns step 1301; If overflow, then execution in step 1303.

Above-mentioned steps 1301～step 1302 is the process in the cycle of control shunt running judgement.

Add up energy accumulation result's the absolute value of unit output of step 1303, calculating energy, sampled point counter and energy accumulation unit carry out inner zero clearing, and execution in step 1304 and step 1302.

In this step, behind the energy accumulation unit output energy accumulation result, execution in step 1304 continues the anti-shunt running flow process in the present embodiment; After sampled point counter and energy accumulation unit carried out inner zero clearing, execution in step 1302 continued the flow process that the cycle is judged in next shunt running.

Step 1304 according to the energy accumulation result, is calculated the absolute value of average power.

In this step, calculate the average power absolute value method can for: ask the merchant of energy accumulation result and sampling number, again the merchant who calculates taken absolute value.

Step 1305 compares average absolute value and the shunt running judgment threshold that sets in advance, if average absolute value, judges then that the calibration pulse in the ic for energy metering is effective more than or equal to the shunt running judgment threshold, and execution in step 1306; If average absolute value, is then judged the calibration pulse in the ic for energy metering less than the shunt running judgment threshold and is the pulse of output down of shunt running state, and execution in step 1307.

Shunt running judgment threshold in this step can be different with the shunt running judgment threshold among the method embodiment one, but set arbitrarily according to the actual conditions in the electric energy metrical, stipulate in the corresponding span but should be in GB.

In execution in step 1301～step 1305, also in the ic for energy metering as shown in Figure 3, the electric current of filtering extraction unit 303 outputs is sampled, and the current sample result who surpasses continuously the current threshold that sets in advance counted, when this count results surpasses predefined number of times, also can execution in step 1307, with this solve since current/voltage phase place angle approaching ± 90 when spending, the be left in the basket problem of metering of active power.

Step 1306 is carried out accumulated counts to the calibration pulse in the ic for energy metering, realizes the electric energy metrical under the non-shunt running state, and process ends.

Step 1307, the calibration pulse signal in the ic for energy metering is invalid, will not measure, and process ends.

In the above-mentioned flow process, when sampled point counter and energy accumulation unit receive systematic reset signal, also carry out inner clear operation.

The creeping prevention method of present embodiment is based on stable energy accumulation mean value as a result, and promptly stable average power realizes.Therefore, the creeping prevention method in the present embodiment is accurate and reliable to the judgement of shunt running state.

The above is preferred embodiment of the present invention only, is not to be used to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of being done, be equal to and replace and improvement etc., all should be included within protection scope of the present invention.

Claims (23)

1, the anti-shunt running circuit in a kind of electric energy metrical is characterized in that, comprising: energy accumulation unit and sampled point counter, wherein,

Sample to the power input in the ic for energy metering under the control of synchronizing signal in described energy accumulation unit, and sampled result is carried out energy accumulation; When the energy accumulation result was overflowed, request sampled point counter carried out inner zero clearing, and the request metering units carries out electric energy metrical; According to the request of sampled point counter, carry out inner zero clearing;

Described sampled point counter adds up to the sampling number of power input under the control of described synchronizing signal; When the sampling number accumulation result overflows, carry out inner zero clearing, and request energy accumulation unit carries out inner zero clearing; According to request, carry out inner zero clearing from the energy accumulation unit.

2, anti-shunt running circuit as claimed in claim 1 is characterized in that, described sampled point counter is further stored the shunt running judgment threshold that sets in advance; When the sampling number accumulation result equals the shunt running judgment threshold, judge that the sampling number accumulation result overflows.

3, anti-shunt running circuit as claimed in claim 1, it is characterized in that, described anti-shunt running circuit further comprises: sample count exclusive disjunction unit, be used for when the spill over that receives from the sampled point counter, perhaps when the output that receives from the energy accumulation unit, perhaps when receiving systematic reset signal, request sampled point counter carries out inner zero clearing;

Described sampled point counter further when the sampling number accumulation result overflows, sends spill over to described sample count exclusive disjunction unit; According to request, carry out inner zero clearing from sample count exclusive disjunction unit;

Described energy accumulation unit is further when the energy accumulation result is overflowed, to the output pulse of sample count exclusive disjunction unit.

4, anti-shunt running circuit as claimed in claim 3, it is characterized in that, described anti-shunt running circuit further comprises: energy accumulation exclusive disjunction unit, be used for when the spill over that receives from the sampled point counter, perhaps when receiving systematic reset signal, request energy accumulation unit carries out inner zero clearing;

Described sampled point counter is further when the sampling number accumulation result overflows, to energy accumulation exclusive disjunction unit output spill over;

Described energy accumulation unit further according to the request from energy accumulation exclusive disjunction unit, carries out inner zero clearing.

5, as claim 3 or 4 described anti-shunt running circuit, it is characterized in that described circuit further comprises: first comparer, counter and second comparer;

Described first comparer under the control of synchronizing signal, is sampled to the electric current in the ic for energy metering; The current sample result is compared with the threshold value that sets in advance, and in the current sample result during greater than threshold value, to the request of counter output counting, otherwise request counter carries out inner zero clearing;

Described counter under the control of synchronizing signal, carries out accumulated counts to the counting request from first comparer, and accumulation result is exported to second comparer; According to carrying out inner zero clearing from the request of first comparer or second comparer;

Described second comparer, under the control of synchronizing signal, to compare with the threshold value that sets in advance from the accumulation result of counter, and at accumulation result during greater than threshold value, to described sample count exclusive disjunction unit requests the sampled point counter is carried out inner zero clearing, and request counter carries out inner zero clearing;

Described sample count exclusive disjunction unit asks described sampled point counter to carry out inner zero clearing further according to the request of second comparer.

6, anti-shunt running circuit as claimed in claim 4 is characterized in that, described energy accumulation unit is active power energy accumulation unit;

Described circuit further comprises: reactive power energy accumulation unit is used under the control of synchronizing signal the reactive power in the ic for energy metering being sampled, and sampled result is carried out energy accumulation; When the energy accumulation result of reactive power is overflowed, in sample count exclusive disjunction unit and ic for energy metering, be used to measure the metering units output reactive power calibration pulse of reactive power; According to request, carry out inner zero clearing from energy accumulation exclusive disjunction unit;

Described sample count exclusive disjunction unit further when receiving the reactive power calibration pulse of reactive power energy accumulation unit output, asks described sampled point counter to carry out inner zero clearing;

Described energy accumulation exclusive disjunction unit further when the spill over that receives from the sampled point counter, perhaps when receiving systematic reset signal, asks described reactive power energy accumulation unit to carry out inner zero clearing.

7, the anti-shunt running circuit in a kind of electric energy metrical is characterized in that, comprising: energy accumulation unit, sampled point counter and judging unit;

Sample to the power input in the ic for energy metering under the control of synchronizing signal in described energy accumulation unit, and sampled result is carried out energy accumulation; The result offers judging unit with energy accumulation; According to request, carry out inner zero clearing from the sampled point counter;

Described sampled point counter adds up to the sampling number of power input under the control of described synchronizing signal; When accumulation result overflows, carry out inner zero clearing, and ask the energy accumulation unit to carry out inner zero clearing, the request judging unit is judged;

Described judging unit receives the output result who is used for electric energy metrical in the ic for energy metering; Request according to sample counter, will from energy add up the energy accumulation result of unit with in advance the storage threshold value compare, and in the energy accumulation result during, the current described output result who receives is exported to metering units in the ic for energy metering more than or equal to threshold value.

8, anti-shunt running circuit as claimed in claim 7 is characterized in that described judging unit comprises: absolute value element, threshold cell, comparer and output control unit;

Further when the sampling number accumulation result overflowed, the request comparer compared described sampled point counter;

Described energy accumulation unit further offers absolute value element with the energy accumulation result;

Described absolute value element is calculated the energy accumulation absolute value from the energy accumulation result of energy accumulation unit, and the energy accumulation absolute value that calculates is sent to comparer;

Described threshold cell is stored predefined shunt running judgment threshold, and offers comparer;

Described comparer receives from the energy accumulation absolute value of absolute value element with from the shunt running judgment threshold of threshold cell; According to the request of sampled point counter, energy accumulation absolute value and shunt running judgment threshold are compared, at the energy accumulation absolute value during, send to output control unit and to allow output signal more than or equal to the shunt running judgment threshold;

Described output control unit receives the calibration pulse in the ic for energy metering; According to permission output signal, the current calibration pulse signal that receives is sent to metering units in the ic for energy metering from comparer.

9, anti-shunt running circuit as claimed in claim 7 is characterized in that described judging unit comprises: absolute value element, threshold cell, comparer, output control unit and shift unit;

Further when the sampling number accumulation result overflowed, the request comparer compared described sampled point counter;

Described energy accumulation unit further offers shift unit with the energy accumulation result;

Described shift unit carries out shifting processing to the energy accumulation result from the energy accumulation unit, obtains average power; Average power is offered absolute value element;

Described absolute value element is calculated the absolute value from the average power of shift unit, and the average power absolute value that calculates is sent to comparer;

Described threshold cell is stored predefined shunt running judgment threshold, and offers comparer;

Described comparer receives from the average power absolute value of absolute value element with from the shunt running judgment threshold of threshold cell; According to the request of sampled point counter, average power absolute value and shunt running judgment threshold are compared, at the average power absolute value during, send to output control unit and to allow output signal more than or equal to the shunt running judgment threshold;

Described output control unit receives from the calibration pulse in the ic for energy metering; According to permission output signal, the current calibration pulse signal that receives is sent to metering units in the ic for energy metering from comparer.

10, anti-shunt running circuit as claimed in claim 9 is characterized in that, described shift unit is the bit wide of described sampled point counter to carry out the figure place of shifting processing from the energy accumulation result of energy accumulation unit.

11, anti-as claimed in claim 8 or 9 shunt running circuit is characterized in that the bit wide of described energy accumulation unit is the bit wide of sampled point counter and the bit wide sum of power input.

12, anti-as claimed in claim 8 or 9 shunt running circuit is characterized in that described counter is a status comparator;

Described judging unit further comprises: first comparer, counter, second comparer and exclusive disjunction unit;

Described first comparer under the control of synchronizing signal, is sampled to the electric current in the ic for energy metering; The current sample result is compared with the threshold value that sets in advance, and in the current sample result during greater than threshold value, to the request of counter output counting, otherwise request counter carries out inner zero clearing;

Described counter under the control of synchronizing signal, carries out accumulated counts to the counting request from first comparer, and accumulation result is exported to second comparer; According to carrying out inner zero clearing from the request of first comparer or second comparer;

Described second comparer under the control of synchronizing signal, will compare from the accumulation result of counter and the threshold value that sets in advance, and at accumulation result during greater than threshold value, output allows output signal to the exclusive disjunction unit, and request counter carries out inner zero clearing;

Described output control unit will be exported to from the permission output signal of described second comparer or described status comparator in described exclusive disjunction unit;

Described output control unit is further according to from the permission output signal of described exclusive disjunction unit, and the current calibration pulse signal that receives is sent to metering units in the ic for energy metering.

13, a kind of energy meter anti-creeping is characterized in that, may further comprise the steps:

The energy accumulation unit carries out energy accumulation to the sampled result of power input, and by the sampled point counter sampling number is added up; When the sampling number accumulation result overflows, energy accumulation unit and sampled point counter are carried out inner zero clearing; When the energy accumulation result is overflowed, the sampled point counter is carried out inner zero clearing, and carry out electric energy metrical.

14, creeping prevention method as claimed in claim 13, it is characterized in that, described energy accumulation unit carries out energy accumulation to the sampled result of power input: the energy accumulation unit is under the control of synchronizing signal, the power input that receives is sampled, and sampled result is carried out energy accumulation;

Described sampled point counter is accumulated as sampling number: the sampled point counter adds up to sampling number under the control of synchronizing signal.

15, creeping prevention method as claimed in claim 13, it is characterized in that, before described sampling number accumulation result overflows, further comprise: the shunt running judgment threshold of sampling number accumulation result with storage in advance compared, if the shunt running judgment threshold that the sampling number accumulation result equals to store in advance determines that then the sampling number accumulation result overflows.

16, creeping prevention method as claimed in claim 13 is characterized in that, described energy accumulation result further comprises after overflowing: sampled point counter and energy accumulation unit carry out inner zero clearing.

17, creeping prevention method as claimed in claim 13 is characterized in that, described carrying out further comprises before the electric energy metrical:

Electric current in the ic for energy metering is sampled, and the current sample result who surpasses the current threshold that sets in advance is continuously counted; If this count results surpasses predefined number of times, then the sampled point counter is carried out inner zero clearing.

18, creeping prevention method as claimed in claim 13 is characterized in that, described carrying out further comprises before the electric energy metrical:

Reactive power in the ic for energy metering is carried out energy accumulation, and when the energy accumulation result of reactive power reaches pre-set threshold, the sampled point counter is carried out inner zero clearing.

19, a kind of energy meter anti-creeping is characterized in that, may further comprise the steps:

The energy accumulation unit carries out energy accumulation to the sampled result of power input, and by the sampled point counter sampling number is added up; When the sampling number accumulation result overflows, the energy accumulation result is compared with the threshold value that sets in advance, and carry out electric energy metrical during more than or equal to threshold value in the energy accumulation result.

20, creeping prevention method as claimed in claim 19 is characterized in that, described with energy accumulation result and the threshold value that sets in advance compare into:

When the sampling number accumulation result overflows, energy accumulation result's absolute value and the shunt running judgment threshold that sets in advance are compared.

21, creeping prevention method as claimed in claim 19 is characterized in that, described with energy accumulation result and the threshold value that sets in advance compare into:

When the sampling number accumulation result overflowed, the merchant of calculating energy accumulation result and sampling number obtained average power, and asked the absolute value of average power, then the absolute value of described average power and the shunt running judgment threshold that sets in advance was compared.

As claim 20 or 21 described creeping prevention methods, it is characterized in that 22, described when the energy accumulation result is compared with the threshold value that sets in advance, further comprise: sampled point counter and energy accumulation unit carry out inner zero clearing.

As claim 20 or 21 described creeping prevention methods, it is characterized in that 23, described carrying out further comprises before the electric energy metrical:

Electric current in the ic for energy metering is sampled, and the current sample result who surpasses the current threshold that sets in advance is continuously counted; If this count results surpasses predefined number of times, then carry out the described electric energy metrical that carries out.

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