DE2630959A1 - KILOWATT-HOUR METER WITH STATIC MEASURING SYSTEM - Google Patents

Description

HELIOLIATT-IjJERKE '1 Berlin 12, July 1, 1976

Elektrizitäts-Gesellschaft mbH klilmersdorfer Str. 39

Kilawatt hour meter with static measuring mechanism

The invention relates to a kilowatt hour meter with a static measuring mechanism, in particular for three-phase networks with voltage dividers and current transformers for level adjustment, with a power supply for the electronic components and with a display device.

Known currently used kilowatt hour meters with static measuring mechanisms work with analog signal processing methods, preferably according to the timerivision approach with subsequent current-frequency conversion. For an economic one Three-phase electricity meters are unsuitable because they are analogue Signal processing precise and therefore expensive components must be used, the temporal inconsistency of which additionally falsifies the measurement result.

The utility companies expect a kilowatt-hour meter to do a lot Hear through uncontrolled can be left in the net and that such a thing Serät remains functional for twenty to thirty years.

The object of the invention is to provide a three-phase current meter with a static measuring mechanism create that meets both the requirements for measurement accuracy and its long-term constancy as well as the reliability at low manufacturing costs.

This object is achieved by the invention as described in the characterizing parts of the claims is shown. It is essentially based on the fact that the measurement processing is digital as far as possible, thus free of errors and drift, takes place that by an automatic zero point and calibration correction the influence the components or circuit parts of the meter that process the measured variables in an analog manner, on the measurement result is eliminated except for a residual linearity error is that a multiplexing process and, as an essential characteristic of the invention, a microcomputer for the control and the measured value processing, the one or two analog / digital transmitters are used.

1 0 SC > ~ <0 S 1 8

The invention is explained in more detail below with reference to the drawing, which from Consists of 5 figures. The

Fig. 1 shows a two-channel multiplex system, the

Fig. 2 shows a single-channel multiplex system, the

Fig. 3 shows a single-channel multiplex system in which all input variables as Current signals are present that

Fig. K shows an overview of the signal sampling options for calculating the instantaneous power, and the

5 shows the scanning sequence of a voltage and a current to form the instantaneous power.

Since a computer can only process digital values, the three Voltage / Strotii pairs of the three phases of the three-phase network into corresponding digital values implemented. It should be noted that the time allocation of the voltage and the current of a phase is used to determine the active power must be preserved. In order to comply with the specified error limits, three-phase meters at most an error of a few angular minutes occur; this corresponds to a time error of a few microseconds at 5 ° Hz.

If you use two analog / digital liJandlers and a two-channel multiplexer, so one can avoid a time error on hosting the expense (Fig. 1).

however, an analog-to-digital converter and a single-channel converter are advantageously used Multiplexer with initially six inputs used. For example, the six Measured variables in the following order from the multiplexer to the analog / digital converter created, successively converted into digital values and sent to the computer Further processing supplied:

^U R - ¹ R - ^U S - ¹ S - ^Ü T - ¹ T

Between the sampling time, for example the voltage LL and the sampling time of the associated current I ₁ , the multiplexing causes a time offset, the amount of which depends on the multiplex frequency.

Since each measured variable is scanned by the multiplexing, its height is determined essentially from which harmonics are still to be detected. Will

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assuming that higher than the tenth harmonic no longer play a role, a sampling frequency ν / απ 1 kHz would be sufficient. If 2 kHz is used, including the (\ iullungs- and calibration cycle ¹⁾ at least 16 kHz = 60 μΞ. In this case, there is a time of 6D μΞ between the sampling of a voltage and the associated current; this makes the measurement of the Active power already inadmissibly falsified.

(because the multiplexer, the analog / digital Lüandler and the computer are so fast are that the multiplex frequency can be increased so far that the remaining Time errors become negligible, then no further measures need to be taken to become. For the computer, multiplying two numbers in a few microseconds is problematic; this requirement can practically only be met by parallel multiplication fulfill.

This means that a faster computer has to be used, which is unnecessarily expensive of the device. In the following, therefore, some methods are explained with which the time error occurring during slow scanning can be largely compensated, so that a computer is important for the processing of the measured values lower performance can be used.

The first l / experienced envisages analog \ / training elements that go into the supply lines looped into the multiplexer for each of the three measured variables sampled later will. If the numerical value of 60 με assumed in the previous example is assumed, so such a delay is difficult to establish and is long Keep time periods constant. At higher multiplex frequencies when the timing error is already small anyway, this method appears to be quite useful in order to largely compensate for this remaining error.

From the patent application P 25375W.9 it is known that the one-channel multi-tiplexing unavoidably occurring time errors useful for hitching elsewhere Signal delays or angle errors in the electronic meter can be used by ensuring that the sign and magnitude of both delays cancel each other out. The amount, however, determines the multiplex frequency stipulates what might contradict other requirements.

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According to the invention, it is proposed that the computer initially always scan a few times saves before it evaluates it. These storage values are varied to use for interpolation or extrapolation calculations.

In the simplest case, by changing the scanning sequence:

^U R - ¹ R - ^U R - ^U S - ¹ S - ^U S - ^U T - ¹ T - ^U T

create a very precise interpolation option.

In this case the multiplexer does not need any more inputs, i.e. with inclusion the zero point and calibration correction eight inputs. The number of bars per However, the multiplexer cycle is increased. The computer can now use the two voltage-scanned, which surround the associated Stromuert on both sides in terms of time, use linear interpolation to calculate the missing voltage and then use the relevant current to determine the instantaneous power multiply.

Another sampling order is:

^U R - ^U R - ¹ R - ^U S - ^U S - ¹ S - ^U T - ^U T - ¹ T

from which the computer determines the voltage associated with the current Extrapolation calculated.

In order to avoid increasing the number of clocks per multiplexer cycle, an interpolation that extends further over time can also be implemented. In this case, the same multiplexer cycles no longer follow one another, but first the three voltages: LL-LL-LL and in the next multiplexer cycle the three currents: I _n - I "- I _{x are} sampled alternately. The computer now interpolates the voltage value associated with a current calculation from the two voltage values taken from the preceding and the following multiplexer cycle. If the multiplex frequency is sufficiently high, the resulting interpolation error remains sufficiently small.

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In principle, it does not matter whether the voltage wire carries the current values Interpolation can be determined. In the case of the l / experienced with double sampling of the voltages or the currents, however, it is useful to sample the currents more often, since the mains voltage is generally quite sinusoidal, while the current, e.g. by thyristor-controlled consumers, can be heavily distorted, so-called that it is more accurately detected by the more frequent scanning.

With interpolation it is also possible to calculate the mean value on the plane the momentary power, i.e. e.g. in the case of the sample series U-I-U can also be the first voltage value with the current value multiply, then the second and average over the two products.

In Fig. 5 it is drawn how - without taking into account the multiplexing of the three Phases - a voltage u (t) and an associated current i (t) are sampled. Let the number of samples be denoted by π. The individual scanned are multiplied as follows:

^p ui ^Ct) = H ⁽ V1 ⁺ Vz ⁺ "2 * 3 ⁺ - ¹ Cn-Z) ¹¹ Cn-I) * V

By inserting the function code the following results are generally obtained:

The result for the relative measurement error of the power is:

The error is neither dependent on the modulation nor on the phase shift between voltage and current, but only on the number of sample values -TD Psriods. However, the period and the number of samples per cycle ^are]: -n £ '': - · represents distinctive MeBfshlsr can therefore sinraalig eingeeicht with and falls

thus out. For a measurement error v / an 1 % there are at least kk samples per period (2 ms); this leads to a sampling frequency of 2.2 kHz. It does not matter whether the voltage and current samples are obtained in one and the same multiplexer cycle or in alternating multiplexer cycles; only the time interval is decisive for the measurement error.

With alternating cycles, the number of clocks in a sampling cycle is reduced to four, whereby the order looks like this, for example:

U _R - U _s - U _T - Zero I _R - I ₅ - Lj.- Reference voltage U _R - U ₅ - LL -

Zero I _R - I "usuj.

Theoretically it is possible, at the moment of scanning a quantity, e.g. a Voltage, the corresponding value of the other quantity, e.g. a current, analog ztüischenzuspeichern so that a temporally related pair for product formation is available. In practice, this is greasy, as with kilawatt-hour meters the measurement error remains constant over the entire measurement range relative to the respective measurement value, so that even very small lines must be precisely recorded. Even the interference from the switching impulses would when using a Analog memory considerably falsify small stored values.

According to the invention, the problems occurring with single-channel multiplexing are solved, the main source of error is the analog-to-digital converter, because the subsequent digital processing by the computer is to be regarded as error-free.

In every single - or with alternating multiplexer cycles, e.g. in every second one Multiplexer cycle - contains a zeroing cycle in which the input of the analog / digital converter is switched to zero potential via the multiplexer. If the analog-to-digital converter specifies a digital value that differs from zero the computer, sd this determines the deviation and saves the value to then digitized every further delivered by the analog-digital converter to be corrected with it before the evaluation. Because of the rapid sequence of zeroing cycles relatively fast zero point drifts of the analog / Digital converter regulated. This means that there is no zero point error over the entire process Lifespan of the device.

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In every multiplexer cycle - or in every other cycle in the case of alternating cycles the input of the analog / digital converter via the multiplexer to a reference voltage whose setpoint is contained in the computer's memory. If the analog / digital handler delivers a digitized value that is dyed against this setpoint, this is how the computer determines the deviation and saves the correction factor and then corrects each delivered goods after having previously received the Had taken zero point errors into account. This eliminates the calibration or slope error over the entire service life of the device.

The residual error is the linearity deviation of the analog / digital LJandler converter characteristic, which, however, can always be kept sufficiently small, since it practically only depends on the precision of a resistor divider chain.

üBased on the requirement for constant relative measurement errors in the entire measuring range it is inexpedient to use a linear analog / digital converter / converter line to work that requires a more complex analog / digital lilandler, its accuracy would not be used for large measured values. According to the invention, a non-linearly stepped characteristic is therefore preferred which is such that the relative measurement error is the same at every point on the characteristic curve. The logarithmic graduation, which is suitable per se for this, is advantageous because it is easier to implement binary gradation replaced. It goes without saying that any desired analog / digital / Llandler converter characteristic curve can be created using a suitable program on the computer consider. All circuit parts of the electronic energy meter listed so far - The multiplexer M, the microcomputer MC and the analog-digital converter AD - including the resistors of the analog / digital converter are monolithic integrable.

In a three-phase meter, for example, voltage dividers and current transformers, such as ferrite pot-core current transformers, are used with or without electronic error compensation. Optionally, the multiplexer and the analog / digital clerk can do all of them Process input signals in the form of voltages or currents, whereby currents can be switched through more easily via the multiplexer; also the comparator of the analog / digital converter preferably compares currents instead of voltages.

In any case, the six input variables must be divided down so that they can be processed by electronics. When manufacturing one

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Counters are e.g. the voltage divider ratios and load resistances adjust the current transformer to their setpoints. Such adjustments require expensive adjustable components and are particularly labor-intensive.

This disadvantage is eliminated according to the invention in that basically all Adjustments are no longer necessary because they are programmed in be replaced in a memory. For this purpose, each individual advisory in a preferably fully automatic test process the actual values of the voltage divider ratios, Current transformer transformation ratios (including the load resistances) and the reference voltage measured and corresponding correction values written in a memory accessible to the computer. A programmable read-only memory (PROM) is expediently used for this, the is included in the computer circuit and automatically operated by the test apparatus is programmed. If a repeatedly programmable read-only memory (RePRDM) is used, the meter can be recalibrated later with the same test equipment by programming in new values.

Electronically error-compensated current transformers are known and allow small ones Ferrite pot cores very precise current translations. However, due to the required auxiliary amplifier, they usually have an offset DC voltage at the output on. When calculating the instantaneous power, there is no error as long as such a DC voltage component is only present at one input of the multiplier is applied; this is to be assumed if the counter - uiie has only been able to do so until now was common - is fed by voltage and current transformers. At a Use with a direct connection, however, can be used with longer cables and thyristor-controlled cables Consumers definitely have a DC component of the voltage, which together with the DC offset of an electronically error-compensated current transformer would result in a measurement error. It is therefore useful if the electronic error compensation is not used. Current transformers with ferrite cores show relatively large errors. When using the procedure described here the automatic tester will be able to read the two error curves each one of the three current transformers in a counter over the entire modulation range and to save in the programmable read-only memory (PROM). Of the The computer is now every single measured value delivered by the analog / digital tüandler evaluate with the associated error curves. Prerequisite for the

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The only way to use this method is to ensure that the error curves of a current transformer remain within the given tolerances over a longer period of time and even after possible severe overloads.

In a further embodiment of the invention, temperature-dependent measurement errors occur largely compensated in the same way that the known and im general temperature coefficients, which are not dependent on the examiner, of the automatic Components recorded for zero point and calibration correction are also stored in the programmable read-only memory (PROM), with a suitable one Temperature sensor is to be provided, the output signal of which is sent to the computer at sufficient time intervals via the multiplexer and the analog-to-digital converter is to be supplied. In the case of particularly high demands on the measurement accuracy, it is of course also possible, e.g. the temperature curve of the one that determines the calibration Reference voltage source to be measured automatically for each individual copy and to be stored in the programmable read-only memory (PRGM).

When the counters are used for a long time, the aging-related drifts of the components not recorded by the zero point and calibration correction are important. This mainly concerns the input voltage dividers, the current transformers and the reference voltage sourceWith well-controlled production, ΠΪ2 aging rates are known and could also be stored in the non-changeable read-only memory (ROH) via the programmable read-only memory (PROM) of the computer. Since energy meters work in most cases with a mains supply for the electronics, a time base can easily be derived from the mains frequency, which is set to PJuIl in the aforementioned fully automatic test process. When calculating the energy, the computer takes into account the respective status of the time base and the aging rates to largely compensate for aging-related influences.

The analog-to-digital converter must be used in an energy meter - especially in a Three-phase meters - process a very large dynamic range. There is his entrance van the multiplexer is constantly switched to other input variables, can its input signal from one sample to the next, e.g. from the maximum negative jump to the maximum positive value. These large signal jumps represent high Ar ^ -rdsrungEn to the comparator of the Analag-Digital-QJandler. The comparator

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needs a certain recovery time after each override. That is critical exact detection of a van from a maximum value to one that jumps close to zero Signal value. The well-known analog / digital handler avoids this Problem with the comparator input signal only the difference between zuiei scans.

In a further embodiment of the invention, the principle of the concurrent Analog-V-digital converters can be used. Each time an input variable is sampled is anyway, as described, the sample value in the computer for the purpose of interpolation saved. The Analog-ZDigital-ldandler sets the Analog value into a digital value that the computer takes over. The Analag-Aiigital-ldandler is then free again and can now before the start of the next one Sampling by the computer for the last sampling value of the input variable to be sampled now can be preset. The comparator again only receives the difference between two consecutive samples. The t / are setting of the analog / The digital converter and the activation of the input variable to be measured are temporal to be coordinated so that a comparator overload is as small as is kept possible.

As already mentioned, it is advantageous to deliver the input variables as currents and to provide a current comparator.

The measuring method described here is opposite to the usual Ferraris meter prone to storm impulses due to its speed. To understand the behavior of the To approximate electronic energy meter that of the Ferraris meter is according to the invention the computer is programmed in such a way that the jumps between two scans are limited in height and that larger jumps are counted as interference pulses will. In this case, such sampling values recognized as disturbed are either to be suppressed entirely, or the part exceeding the programmed maximum value is used subtracted. Moving averaging is also possible. This takes place the averaging before or after the calculation of the instantaneous power.

By appropriate programming of the computer it can be achieved that the multiple undesired accuracy of the measurement with respect to the detection of harmonics of the mains frequency is reduced and that of a Ferraris meter is approximated. For this purpose, e.g. a Fourier transformation (FFT) is carried out by the computer.

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After calculating the instantaneous power of each phase by multiplication a digital attendant is available as a result, with a three-phase meter according to the relationship of the three phases are to be added. To determine the energy integration over time is required.

The energy consumed is recorded in a cumulative counter and on a Display device shown. For this purpose, the well-known counting uno storers Roller counters with stepper motor drive can be used, but it is also possible, storing electronic display devices, e.g. electrochromic or electrolytic ^ displays. Also a normal non-saving electronic display is possible if a non-volatile memory, e.g. MfJDS memory is available. Because of the limited number of write cycles, which a salcher memory can perform before it becomes unusable, one only becomes the one to be rescued in the event of a recognized imminent! Metz failure Write the numerical value there.

In any type of digital display, one jump corresponds to the smallest digit a certain amount of energy consumed. These counting pulses can be obtained, for example, by opening the computer after determining the total momentary power counts as many periods of a reference frequency as it corresponds to this instantaneous power; these counted impulses are now direct or to be supplied to the advertisement after corresponding frequency division. It is also possible, with the current output available as a digital type, a programmable one Frequency divider to switch over, which constantly receives the pulses from a reference frequency source divided by the programmed factor. The network frequency is preferably used as the reference frequency; it is also possible to change the clock frequency of the computer via a phase-locked loop (PLL) from the mains frequency or to use a quartz. The computer is through an appropriate Make the program count down certain times; also the one in many computers programmable timers included can be used to advantage.

A special test output of the computer is advantageous for test purposes, on which the consumed energy is available with a shorter measuring time than at that for the display device determined output.

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üJwirtschaftliche campers work with relatively low clock frequencies and need therefore, e.g. for multiplications, long times. To save time with Multiplying is based on the principle of the parallel analog / digital converter Make use of it by not using the full voltage and current values every time are multiplied with each other, but only the difference values to the previous ones Samples according to the following scheme:

^u n * ¹ O = ¹ Wl

Is the multiplication time for purely serial processing for such a Application too long, a separate parallel multiplier must always be used, Dhne that the measuring principle described would change.

A particular problem with electronic energy meters is immunity to interference. Usual Ferraris meters can withstand extremely high peak voltages on the Inputs, they often withstand peaks of more than 10 kV. Which as beneficial proposed current input - also on the voltage side - turns out to be also in this regard as cheaper, since there is practically no tension on the device side occur, so that very effective protective measures are possible.

In the case of an energy meter with a computer, special precautions must be taken against the penetration of disturbances into the electronics can be taken as a glitch in the case of a computer, not only to wrong data, but also to wrong data Command can lead. In this respect, too, the patent application proves itself P 25375 ^ 9.9 proposed single-chip microcomputers as superior because the effects of interference become minimal when the entire computer is used is integrated on a single semiconductor crystal. Disturbances then only work still on the inputs and outputs of the computer, with interference at the inputs only temporarily generate incorrect input data, but not incorrect one Cause the program to run.

The invention will be explained below with reference to a few figures:

In Figure 1, the less advantageous because more complex solution is initially with a two-channel multiplexer M and two analog-ZDigital-lilandlern AD ,, AD " shown. Oeder multiplexer M has five inputs, since each of the two multiplexers

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xer channels and each of the two analog-to-digital converters AD ", AD" with regard to their zero point and calibration errors must be corrected. The microcomputer MC controls both the multiplexer M and the analog-digital converter AD., AD ". For the purpose of the energy calculation, he also receives the reference frequency f "

rer

guaranteed. The accumulated energy consumption is shown on a display device Ξ-meaning displayed, in this as in the following images it is assumed that the microcomputer fC also contains the required memory. This also applies to the electrically programmable memory for recording mentioned several times the correction curves or values. It is e.g. a metal-I \! Itrid-Üxyd semiconductor memory (MWUS) can be used. Of course, it is also possible to assemble the microcomputer MC from several integrated circuits; never changes the idea behind the invention.

Furthermore, according to the prior art, it is possible to _{accommodate the analog-to-digital converter AD 1, AD n} together with the associated resistors and also the □ of the multiplexer H together with the computer on a single circuit. The entire electronic three-phase meter then essentially consists of three current transformers, a resistor arrangement (e.g. thin-film, thick-film technology), the large circuit, the display and the power supply. As described, it does not have any adjustable or adjustable components.

Ir FIG. 2 shows the more advantageous solution with a single-channel multiplexer H and only one analog-to-digital converter AD, all input signals of the multiplexer M being present in the form of voltages. The order in which the connections are drawn is not necessarily identical to the order in which the input signals are sampled by the multiplexer M. The computer sends the address of the desired input to the multiplexer M via a control line; the order depends on the selected program.

In Figure 3, the circuit is drawn for the case that all input signals of the multiplexer M are in the form of current signals.

Various possibilities for sampling the signals are shown in FIG and to calculate the instantaneous performance in each case; Figures 4a, b and c ^ 2zi2'nsn here on the measurement of only one phase, while the figures

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kü, κ and f apply to the measurement in three phases.

The invention can be used for any number of phases, e.g. also for a so-called three-wire meter in which only two measuring channels are required .

The sampling and interpolation in the voltage and current measurement in a single-phase network is shown in FIG. 3: the indices denote the number of the sampling concerned; the voltage and current input are scanned alternately. A first partial product (instantaneous output) p. results, for example, in that from the two voltage samples u _n and u _? a voltage value is interpolated, which is then multiplied by the current sample value I _1. A further partial product p ₃ arises, for example, from the fact that a Lüert is interpolated from the two voltage values u 1 and u, which is then multiplied by the current value i. The total power P results for a certain number of samples π as:

Here, η multiplications are carried out.
2

Voltages and currents are completely equal and can therefore be interchanged.

In FIG. 4b, a different product formation is described for the same case of alternating sampling of input voltage and input current: from the existing ones Samples are now formed partial products ρ, with alternating the voltage or the current is interpolated. The power P is calculated here as:

P = - (P ₁ + P ₂ + P ₃ + · ..)

In FIG. Kc , an example is drawn for the case in which the averaging takes place only after the partial test products ρ have been formed. The total power P results as in case 4b, but here only one memory is required for only one sample, because before the multiplication there is no interpolation _mGnr or no mean value is formed any more.

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For all three! / Experienced applies:

^{P =} n- ^C Vi ⁺ Vs ⁺ VS + i ₃ ^ + -)

For the practically most important part of the measurement in a three-phase system is initially in Figure ^ d the sampling of the phase R, FIG ke in the sampling of the phase S and in FIG ^ the sampling of the phase T f shown. The scanning sequence was:

^U R - ¹ S - ^U T - ¹ R - ^U S - ¹ T

provided. The arrows marked with the partial products ρ indicate how these partial products were created.

A large number of scan sequences are possible; some for the method according to the invention typical are e.g .:

^U R - ¹ R - ^U R - ^U S - ¹ S - ^U S - ^U T - ¹ T - ^U T

^U R - ¹ R - ^U R - ¹ S - ^U S - ¹ S - ^Ü T - ¹ T - ^U T - ¹ R - ^U R - ¹ R - ^U S - ¹ S

¹ T- ⁰ T " ¹

¹ T

^U R - ^U S - ^U T - ¹ R - ¹ S - ¹ T

^U R - ¹ S - ^U T - ¹ R - ^U S - ¹ T

As mentioned, the computer determines which input signal the multiplexer M each should switch through, so that depending on the program in the same circuit any Scanning sequences and any type of evaluation of the scans are possible is.

In the case of the energy meter with computer described here, the sampling according to FIG. Ka is particularly useful because a computer can add relatively quickly, but requires a comparatively very long time for a multiplication; however, according to FIG. 4a, multiplications are only carried out.

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For the sake of clarity, the scanning of the zero bzuj was shown in FIG. Reference potential omitted. Oe according to the expected drift of the! bzuj. The only requirement of the calibration is that the zero or calibration potential is sufficient scanned at time intervals and formed and corresponding correction guards get saved. So it is by no means necessary to scan in every cycle of the input variables also include the two other variables mentioned.

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Le

r s e i t e

Claims (1)

Patent claims : ) y Kilauiatt-hour counter with static Meßujerk, especially for three-phase networks with devices for adapting the input variables to the processable by the electronics level with a power supply for the electronic components and with a display device, characterized in that the Messuierk (Fig. 2,3) from a single-channel multiplexer (M) with eight inputs, an analog / digital handler (AD) and a computer (MC), in which one input of the multiplexer (M) is connected to IMull potential, another input to a reference potential (LJ "), three inputs with the input voltage variables (LL, Ug, LL) and three inputs with the input current variables (I _R , I _q , Ι _χ ) are connected, so that the computer (MC) uses the multiplexer (M) to determine and store a zero point error value. the zero potential and the reference potential (LJ ") to determine and store a calibration error are switched to the analog / digital converter (AD) at sufficient intervals It is ensured that the computer (MC) applies the correct sign to all input variables supplied to it via the multiplexer (M) and the analog / digital converter (AD) in a digital farm before further processing with the stored zero point error and the stored one corresponding to the calibration error Correction factor linked, that the multiplexer (M), controlled by the camper (MC), feeds the input variables in a given order via the analog-ZDigital-UIgndler (AD) to the computer (MC) so that the computer (MC) saves a given number of scanning tables of the input variables, that the computer (MC) to determine the instantaneous power from the stored samples with the help of linear inter- or extrapolation before or after the execution of the multiplication compensates for the error resulting from the successive sampling of related input variables, that the determined instantaneous power of the individual phases is added up with a reference frequency (f _f ) is combined and supplied to a corresponding one of the consumed energy information to a nonvolatile memory with a display device or a stored indication that the Istabioeichungen from the desired values of the non from the automatic zero and egg · deviation correction detected T _E ile of the counter souiie the reference voltage source (U _f ) and corresponding correction values are stored in an electrically programmable memory and taken into account by the computer (MC) when calculating the energy consumption. - 18 - 709882/0 518 ORiGiNAL INSPECTED 2) kilawatt hour meter according to claim 1, characterized in that the clock frequency of the computer from a quartz wire via a phase locked loop (PLL) is derived from the network frequency. 3) kilowatt hour meter according to claim 1 and claim 2, characterized in that that the clock frequency of the camper as a reference frequency for the integration used. if) kilawatt hour meter according to claim 1 to claim 3, characterized in that that the multiplex frequency is synchronized with the [Metz frequency. 5) kilawatt hour meter according to claim 1 to claim k, characterized in that the multiplex frequency runs freely with respect to the mains frequency or is additionally frequency modulated. 6) kilawatt hour meter according to claim 1 to claim 5, characterized in that that the multiplex frequency over the program of the clock frequency of the computer is derived. 7) Kilawatt hour meter according to claim 1 to claim S, characterized in that the Meßoierk (Fig. 1) consists of a zuieikanaligen multiplexer (M) each with five inputs, zuiei analog / digital üJandlern (AD., AD ") and a computer (MC) consists, where one of the five inputs is at zero potential, a second of the jEüJEÜs five inputs at a reference potential and the input variables LL, U ₁ -., LU the remaining three inputs of one, and the input variables I _R , Iq. Ip are fed to the remaining three inputs of the other multiplexer (M) and transmitted to the computer (MC) in the digital farm _{via the two analog / digital converters (AD., AD 2).} 8) Kilouiatt hour counter according to claim 1 to claim 7, characterized in that the computer (MC) for integrating the instantaneous power by program control counts one of the respective instantaneous power corresponding number of periods of a reference _{frequency (f f} ) and feeds this to the storing display device. - 19 - 9) kilowatt hour meter according to claim 1 to claim 8, characterized in that that the calculated instantaneous power for setting a programmable Frequency divider or multiplier is used, the pulses a reference frequency (f _) divides or multiplies and that the so obtained Counting pulses as a measure of the energy consumed in the storage display are fed. 10) kilouatt hour meter according to claim 1 to claim 9, characterized in that that the clock frequency of the computer is used as the reference frequency and that the Time specification required for the integration in a manner known per se by a Program loop or is generated by a timer integrated on the computer circuit. 11) kilowatt hour meter according to claim 1 to claim 1D, characterized in that to compensate for the time delay in single-channel sampling and analog / digital Ul _a ndlung the later sampled value of a voltage-current pair is delayed accordingly with the help of an analog Uerzögerungselement . 12) kilowatt hour meter according to claim 1 to claim 11, characterized in that that with single-channel multiplexing at the moment of sampling a quantity of Corresponding instantaneous value analogous to the value belonging to the voltage-current pair buffered and then fed to the analog-to-digital converter (AD) is. 13) kilowatt hour meter according to claim 1 to claim 12, characterized in that that, when determining the sampled value, the time to the sampled value belongs to the other size of a voltage-StrDm pair and because of the single-channel multiplexing cannot be queried simultaneously from the computer at least two sample values of the one variable by means of inter-adder extrapolation the missing one is calculated. - 20 - 709862/0518 Kilowatt hour meter according to Claim 1 to Claim 13, characterized in that that with a single-phase energy meter the single-channel multiplexer from the computer controlled alternating the input variables voltage and current as well as in sufficient time intervals also zero potential and a reference voltage scans and that the Camputer based on the program entered into it always keeps the two last sampled values stored that he an interpolated value is calculated for each individual sample from the sample just obtained and the previous sample of the same size available in the memory and this with the size available in memory for the other size Determination of the instantaneous power multiplied so that alternating interpolation times calculated for the voltage and the current and with the instantaneous Value of the other quantity can be multiplied. 15) KilDUiatt hour meter according to claim 1 to claim 14, characterized in that that with a single-phase energy meter the single-channel multiplexer from the computer controlled alternately the input variables voltage and current as well as sufficient time intervals i \ lullpütential and samples a reference voltage, that the computer calculates the mean value from two consecutive samples of one variable by interpolation and this in each case multiplied by the intervening sample of the other variable. IS) Kilcwatt hour meter according to claim 1 to claim 15, characterized in that that with a single-phase energy meter the single-channel multiplexer from the computer controlled alternating the input variables voltage and current as well as in scans zero potential and a reference voltage at sufficient time intervals, that the camputer continues two consecutive times Samples of both quantities are multiplied with one another and the partial products E are summed up. 17} Kiiowatt hour meter according to the preceding claims, characterized in that that with a multi-phase energy meter it is a single-channel multiplexer from the computer controlled the voltages and currents of the phases and samples zero potential and a reference voltage at sufficient time intervals, wherein the input variables are scanned one after the other as follows: ^U R - ¹ R - ^U R - ⁰ S - ¹ S - ^U S - ^U T * ¹ T - ^U I - 21 - 709882/0518 -2H- 18) kilowatt hour meter according to the preceding claims, characterized in that that with a multi-phase energy meter the single-channel multiplexer / om computer controlled the voltages and currents of the phases as well as in sufficient time intervals füullpotential and a reference voltage scanned, uiobei the input variables are scanned one after the other as follows: V ¹ R - ^U R - ¹ S - ^U S - ¹ S - ^U T - ¹ T - ^U T - ¹ R - ^U R - ¹ R - ^U S - ¹ S - ^U SI ₁ . - U ₁ . - I ₁ . 19) kilowatt hour meter according to the preceding claims, characterized in that that with a multi-phase energy meter the single-channel multiplexer from the computer controlled the voltages and currents of the phases souiie in sufficient time intervals f \ lullpotential and a reference voltage is sampled, uiobei the input variables are scanned one after the other as follows: ^U R " ^U S" ^U T " ¹ R" ¹ S ~ ¹ T 2ü) Hiloujatt hour counter according to the preceding claims, characterized in that that with a multi-phase energy meter the single-channel multiplexer from the computer controlled the voltages and currents of the phases and scanned IMull potential and a reference voltage at sufficient time intervals, wherein the input variables are scanned one after the other as follows: ^U R - ¹ S - ^U T - ¹ R - ⁰ S - ¹ T 21) kilowatt hour meter according to claim 1 to claim 2G, characterized in that that all signals fed to the analog / digital converter via the multiplexer are transformed into stresses, provided they are not already present as stresses. 22) kilowatt hour meter according to claim 1 to claim 21, characterized in that that the signals fed to the analog / digital converter via the multiplexer are converted into currents, provided they are not already present as currents. - 22 - 709882/0518 23) kilawatt hour meter according to claim 1 to claim 22, characterized in that that the converter characteristic of the analog / digital converter is stepped so that the relative measurement error related to the respective measured value regardless of the Control remains constant and that the computer uses the converter line of the Analog / digital liJandlers in the further processing of the delivered by them Values taken into account. 2k) kilowatt hour meter according to claim 1 to claim 23, characterized in that the analog-digital converter has a logarithmically graduated converter line and that the computer takes this into account in the further processing of the numerical values supplied by the analog-digital converter. 25) HiloLüatt hour meter according to claim 1 to claim Zk, characterized in that the analog-digital converter has a binary stepped converter line and that the computer takes these numerical values supplied to the analog-digital converter into account in the further processing of the νση. 2b) KÜD watt hour meter according to claim 1 to claim 25, characterized in that that the computer-controlled analog-to-digital converter in addition to multiplexing is designed as a running analog-to-digital converter and the analog-to-digital converter before the start of the sampling of a certain Size is already set to the previous sample of the same size, so that the comparator of the analog-to-digital converter only has the difference between the new and the old sample needs to process. 27) kilowatt hour meter according to claim 1 to claim 26, characterized in that that when calculating the instantaneous performance, the computer does not always use the full samples of voltage and current, but only the previous ones stored Value multiplied by the current or voltage difference. 28) kilowatt hour meter according to claim 1 to claim 27, characterized in that that a parallel multiplier is used to calculate the instantaneous power will. - 23 - 709882/0518 - 21 * - 29) kilowatt hour meter according to claim 1 to claim 28, characterized in, that the AnalGg- / Digital-üJandler and possibly also the multiplexer together with the computer is integrated on a single semiconductor crystal, and that in addition to the power supply, only the six level-matched ones are connected to this circuit Input variables and the display device for energy consumption are to be connected. 3D) Hilowatt hour meter according to claim 1 to claim 29, characterized in that that electronically fault-camped current transformers are used and that the Computer is programmed in such a way that it takes from the analog-ZDigital-bJandler Eliminate an incorrect offset constant component contained therein, which comes from the auxiliary amplifier of the current transformer when calculating the instantaneous power eliminated. 31) Hilouiatt hour meter according to claim 1 to claim 3D, characterized in that that the computer is programmed to deal with distorted input signals only the fundamental wave is taken into account when calculating the instantaneous power. 32) Hilowatt hour meter according to claim 1 to claim 31, characterized in that that the computer distorted at one Em for the purpose of calculating the fundamental wave Input signal performs a Fourier transform (FFT). 33) Hilowatt hour meter according to claim Ί b3s claim 32, characterized in that that the computer is programmed in such a way that it evaluates jumps in the samples which exceed a predetermined height as disturbances and that it either subtracts the excess portion or discards such disturbed samples. 34) Hilowatt hour meter according to claim 1 to claim 33, characterized in that that the computer is programmed in such a way that it takes a moving average when calculating the instantaneous power or the energy. 35) Hilowatt hour meter according to claim 1 to claim 3k, characterized in that the energy meter or the Cnmputerschaltkreis itself contains an electrically programmable memory, the content of which is retained even if the supply voltage fails. - Zk - 709882/0518 36) Kilouatt hour meter according to claim 1 to claim 35, characterized in that that the energy meter bzuj. the computer circuit itself is an electrical one Contains writable and readable non-volatile memory (e.g. MNOS memory) and that this memory is refreshed at sufficient time intervals to ensure that the darts are stored once Data are preserved. 37) Hiloüjatt hour counter according to claim 1 to claim 36, characterized in that that the accumulated meter reading (energy consumption) in the event of a failure of the mains supply stored in a non-volatile memory. 36) Kilcwatt hour meter according to claim 1 to claim 37, characterized in that that the energy meter includes an electronic display device from Computer controlled. 39) kilowatt hour meter according to claim 1 to claim 38, characterized in that that the energy meter contains a storing display device. 4G) kilowatt hour meter according to claim 1 to claim 39, characterized in, that the energy meter has a protected connection for a (e.g. portable) test device with the help of which the meter can be checked in a very short time can. 41) Hiloujatt hour counter according to claim 1 to claim 40, characterized in that that the energy meter has its own connection or the protected connection Outputs counter reading with a counter identification. h2) Kilouiatt hour meter according to claim 1 to claim 41, characterized in that that the output of the counter reading is combined with a counter check. 43) kilowatt hour meter according to claim 1 to claim 42, characterized in that that the computer contained in the energy meter in addition to the pure energy calculation In addition, one vein takes on several such tasks as they have been up to now are common for energy meters with additional devices (maximum meter, over-consumption meter, Fixed meter counters, limit value contacts, etc.) - 25 - 709832/0518 - -25 - 44) KilouattstundEnzähler according to claim 1 to claim 43, gEkEnnzeichnst characterized exerts that Cümputsr dES Energiezählera at the takeover of the tasks of a ripple control receiver's programmed to εγ with bskannten methods of digital filtering, not only the decoding of the ripple control commands, but also filtering out the ripple control pulses after appropriate PE adjustment and signal processing. 45) KiloLüatt hour counter according to claim 1 to claim 44, characterized in that that when taking over the tasks εϊπεξ ripple control receivers do the programming dos ripple control receiver in the non-volatile memory of the counter or Computer is included. 46) KilDuatt hour counter according to claim 1 to claim 45, characterized in that that when taking over the tasks of a ripple control receiver by the CornputEr OF THE ENERGY METER The energy meter is also intended for the energy customer Outputs SignalE. 47) HilDLijatt hour counter according to claim 1 to claim 4G, characterized in that the energy meter bziu. the computer circuit contained in it itself contains an electrically programmable or often reprogrammable memory in which the correction value bzuj. Correction cures for all components of the meter are included, which are not recorded by the automatic zero point and calibration correction, their properties bzu. However, the values are included in the measurement, and that the computer is programmed in such a way that it takes the current horror values into account when calculating the energy consumption. curves be taken into account (eg division factors of the input voltage divider, amounts and Fehluiinkel the StromuandlerübersEtzungsvErhältnissE, reference voltage, reference frequency). 48) Hiloüjatt hour counter according to claim 1 to claim 47, characterized in that that the energy meter contains all kinds of adjustment or setting elements that the calibration of the components still included in the measurement result of your Target values are determined each time and the corresponding correction values are added. curves in the electrically programmable memory of the counter bzu. Computer circuit saved and that the computer uses the energy calculation jeujHurried corrections bzu. curves are taken into account. - 26 - 709882/0518 -ζε - k3 ~) Kilowatt hour meter according to claim 1 to claim kB, characterized in that when determining the deviations of the components still included in the measurement result from the setpoint values, the multiplexer present in the meter and the existing analog / digital converter are also used by the Input signals suitable for the counter are placed and the actual values are tapped in digital form at the output of the analog / digital converter or at a suitable output of the computer, so that all the curves or correction curves measured over the level control reflect the individual deviations of both the multiplexer and the analog - / Digital-liIandlers van der Sall converter characteristic between 0 % and 1DG % of the measuring range, whereby with a corresponding number of measuring points per correction curve every deviation of the converter characteristic from its Sall course (linear, logarithmic, binary etc.) up to any small residual error is compensated. 50) kilowatt hour meter according to claim 1 to claim kB, characterized in that a correction curve for the amount and a correction curve for the error angle is determined, stored and taken into account in the calculation for each individual current transformer. 51) kilowatt hour meter according to claim 1 to claim 50, characterized in that that generic or individual temperature coefficients or temperature curves the components still included in the measurement result in the read-only memory (ROM) or in the programmable read-only memory (PROM) or in the electrically changeable Read-only memory (EaRGM) of the counter or computer circuit is stored are that the counter contains a temperature sensor that the input signal this temperature sensor is fed to the computer, e.g. using the existing multiplexer and analog / digital converter, and that the computer uses the measured operating temperature when calculating the energy consumption and the stored temperature dependencies are taken into account. - 27 - 709882/0510 52) Ki ^ watt hour meter according to claim 1 to claim 51, characterized in that that generic or individual aging rates are still included in the measurement result Components in read-only memory (ROM) or in programmable read-only memory (PROM) or in the electrically changeable read-only memory (EaRDM) of the Counter or Camputerschaltkreises are stored that the counter is a free running wire wan has a reference frequency derived time base, and that the computer when calculating the energy consumption the aging rates and the current status of the time base is taken into account. 53) Hiloujatt hour meter according to claim 1 to claim 52, characterized in that that the computer is programmed in such a way that, when the counter is checked, new correction values are obtained due to the aging of the components that has occurred in the meantime or curves are written into the memory. 54) kilowatt hour meter according to claim 1 to claim 53, characterized in that that the electrically programmable memory of the counter or computer circuit additionally contains a counter identification, which consists of a serial number and possibly a data code and a check code. 7OS882 / O518