MXPA96002731A - Measurement process to measure rechargeable electrical consumption of electronic and electronic electronic network - Google Patents

Abstract

The present invention relates to the measurement process for measuring a chargeable electrical consumption of an electrical network, characterized in that it comprises the steps of: a) carrying out a permanent measurement of the consumer current, b) integrating the value of the current measure with respect to the time until the value (Ah) is obtained in relation to the electrical consumption by the consumer, c) adjust the integration step b) depending on the electrical voltage of the network until the adjusted value is obtained (A : h.), which is proportional to a pre-established power consumption unit, and d) calculate the number of pre-established units obtained, in order to obtain the proportional value to the loadable power consumption at any time

Description

MEASURING PROCESS FOR MEASURING THE ELECTRIC LOADING OF AN ELECTRICAL NETWORK AND ELECTRONIC ELECTRICITY METER DESCRIPTION OF THE INVENTION The present invention relates to a process and an electronic electricity meter, preferably to measure the consumption of small consumers of electrical energy, such as the inhabitants in the peripheries of large cities and in the country. Many electricity distributors currently have to face serious difficulties related to the large number of consumers in the region of the lower billing limit, which in Brazil, for example, is around 30 kWh / month (known as the minimum rate). mandatory). The billings of such consumers often fail to reward distributors for their investments made in facilities, mainly with respect to the installation of electricity meters. The simplest conventional meter, that is, a single-phase electromechanical meter, as described in "Electrical Metermen's Handbook," 7th Edition, edited in 1965 by the Edison Electric Institute, is the product of a technology that is more than one hundred years old. - of seniority, which has been subjected for a long period to improvements and cost reductions, which does not seem for more time to be suitable for an additional simplification or reduction of costs. On the other hand, meters that employ an electronic technology, such as that taught in French Patent FR 2,555,318 do not cause cost reduction, but rather only cause the simplicity of implementing multiple functions by reducing the increased costs and this has justified its application only for large consumers. This is due to the relatively high cost of electronic circuits for calculating electrical power and protection and auxiliary power circuits, which are characteristic of state-of-the-art meters. In the case of a cost reduction of electronic circuits for calculating electric power, the French patent FR 2,694,405 proposes a simplification of the measurement process, reducing the complexity of the circuits and the overall cost. This approach includes the evaluation of the electrical consumption by altering the electrical quantity that is measured .. The quantity normally used is an active energy obtained by integration, in relation to time, the active power, which, in turn, is provided by P = VI (power factor) or P = VI eos f, where: V is the voltage module of the main power supply voltage; I is the electrical current module produced by the load base in V; and f is the phase angle between V and I (the electrical signals by time, correspond respectively to the voltage and current). The simplification of the measurement process is obtained by evaluating only the electrical consumption of the electric current I or the combination of the electric current I and the voltage V, ignoring in both cases the information related to the difference in the phase angle f. In the first case, corresponds only to the use of current I, the basic quantity is ampere-hour (A.h.) and, in the latter case, Volt. Amp-hour (V.A.h.). Without taking into account the information of f, a substantial reduction of costs of the electronic circuits responsible for the measurement results, although other measurements become necessary to maximize the reduction of costs, that is, the elimination of the protection circuits and auxiliary measurement, characteristic of the prior art, since it is an international practice to use a linear voltage as the power source for the electronic circuits of the meters.

Another aspect that has become fundamental in the analysis and conception of electrical consumption measurements is the quality of energy. Modern electricity distribution systems in many cases simultaneously supply millions of consumers, which currently constitute interconnected networks. These consumers have the most diverse characteristics, as in the case of the residential / commercial segment where there is a massive use of electrical appliances, computers and fluorescent lighting; and the industrial segment, where heavy loads are used intermittently using electronic switches (thyristor type). The final result is an increase in the pollution of the distribution of the network, mainly in terms of an appearance of parasitic frequencies in the system, of multiple fundamental frequencies (50 or 60 Hz), of harmonic elements and in the reduction of quality of the power factor of the same power. In this case, one must consider the possible irregularities in the power supply of the electrical voltage, to which the distribution system is subject. Overvoltages, for example, characterized by the feeding of a higher electrical voltage module at the maximum electrical voltage allowed in the system, reduces the life of incandescent lights and unnecessarily increases the consumption of electric motors and household appliances. In the case of a voltage drop (voltages below the permissible minimum), there is a considerable reduction in the efficiency of the motors / compressors that are used, for example, in air conditioners and refrigerators, and the efficiency of the illumination of the lamps. In view of these observations, it is easy to see that the attempts of the previous technique have not reached a single solution with respect to the necessary qualities, all at the same time,. Such qualities are: - the scope of the aspects mentioned above with respect to the quality of the energy, both on the side of consumption and on the side of the supply; - the reduced cost that allows a wider application, supplying a market of ten million consumers that includes the global distribution system. This will become evident next with the brief discussion of a typical approach to the prior art. DISCUSSION OF THE PREVIOUS TECHNIQUE in the French patent FR 2,694,405, mentioned above, the cost aspect is considered, although such a patent does not exhaust the existing possibilities, independently of ignoring important aspects related to the quality of the food, for example, the measurements related to consumption included in the global distribution system. This will become evident next with the brief discussion of a typical approach to the prior art. DISCUSSION OF THE PREVIOUS TECHNIQUE in the French patent FR 2,694,504, mentioned above, the cost aspect is considered, although such a patent does not exhaust the existing possibilities, independently of ignoring important aspects related to the quality of the supply, for example, the measurements related to overvoltages and voltage drops in the power supply network; - in the patent of the U.S.A. 5,198,751, it is considered in an isolated manner an aspect related to the quality of consumption, the power factor, through the conception of a meter of Volt. Ampere-hour (V.A.h.) reactive. This approach only contemplates the conventional measurement (active energy), which is still necessary and, therefore, does not satisfy the low cost principle and does not provide the measurements related to the quality of the power supply (overvoltage and low voltage) and the presence of parasitic harmonic elements in the network; - DT 24 444 451 and 0 432 386 patents are related to the implementation of complex meters, which by means of a large number of sub-circuits, try to extract the largest amount of possible information related to electrical consumption and conditions of food. This approach invariably leads to naturally costly solutions related to a difficult use and restricted application, in view of the large amount of simultaneous information related to the system with which the distributors are obliged to work, in order to arrive at a final value that will be charged to the consumer by the electric power supply service; - the patent of the U.S.A. 5,298,856 still increases the level of complexity related to the US patent. 5,198,751, previously mentioned, when defining a setting of the V.A.h meter using various internal tables related to the presence of parasitic harmonic frequencies that may be present in the power supply network. Therefore, it is a solution that does not satisfy the aspects related to the quality of the power supply (overvoltage and low voltage) and only meets the conventional measurement (active energy), independently of being of high cost, in view of the complexity of the circuits. In order to provide a solution that satisfies the previously mentioned requirements of reduced costs and of a scope related to the quality aspects, both in the feeding and in the consumption, the present invention provides a measurement process and an electronic meter for billing the electricity consumption, with innovative features compared with the solutions of the previous technique. In accordance with the present invention, the measurement process for measuring a chargeable electrical consumption of an electric network comprises the steps of a) carrying out a permanent measurement of the current of the consumer; b) integrate the value of the measured current with respect to the time until a value (A.h.) is obtained with respect to the consumer's electricity consumption; c) adjust the integration of step b) according to the electrical voltage of the network until a set value (Av.h) is obtained that is proportional to the preset power consumption unit; and d) calculate, at any given moment, the number of pre-established units obtained, in order to obtain a value proportional to the chargeable electric consumption. The correction of step c) is preferably carried out in pre-established proportions, according to the deviation bands of the network voltage, of the nominal voltage of the network. In the preferred embodiment of the present invention, such bands comprise: a first nominal voltage band on either side of the nominal voltage of the network; - a second overvoltage band; - a third extended voltage band, lower than in the first nominal band; and - a fourth low voltage band, lower than in the third extended voltage band. The correction within the first band can increase linearly from a first negative value at the lower end of the first band to a first positive value at the upper end of the first band, the correction within the second overvoltage band can be constant and equal to the first positive value, the correction within the third extended voltage band can be increased linearly by a greater proportion than in the first band, from a second negative value in its lower end to the first negative value in its upper end, and the Correction in the fourth band can be constant, preferably 100% negative. In the preferred embodiment of the invention, the linear proportion of an increase in the third band is twice the linear proportion of the correction in the first band, considering that the first positive value is + 10% and the first negative value is - 10% Further in accordance with the present invention, an electronic electricity meter for measuring the chargeable electrical consumption of a power supply network comprises a circuit, without a power source, defined by a current transformer (CT) adapted to be associated, as a primary line, with the consumer's load line, the transformer has a secondary winding adapted to generate a current representative of the current of the consumer's load line, an integration circuit connected to said secondary winding to integrate the value of the current in the secondary winding with respect to time, a detector element for detecting when the value integrated by the integration circuit arrives at a preset unit value chargeable as a power consumption unit and a counter element associated with the detector element for summing the detected units of electrical consumption. Agree yet with another aspect, the invention provides an electricity meter comprising a one-piece plastic housing, having at least one continuous passage to receive a consumer phase conductor, a window for observing a consumption unit counter that is part of a circuit of consumption measurement mounted inside the housing, and elements for mounting the housing on a support surface. THE INVENTION The invention, according to a first aspect related to the measurement process, allows a complete separation between the power and consumption systems. The basic concept used is that the power system is characterized by the voltage present in the electrical network, considering that the consumer is defined by the electric current that it takes from the power network. By integrating the current taken by the consumer with respect to time, according to a relative adjustment depending on the value of the voltage fed by the system of the network, it is possible to establish a single quantity that is simple to calculate, which leads to a conception of meters less expensive and that attend the concepts of quality of energy, previously mentioned. The integration of the electric current, which characterizes the consumer, allows the generation of a power and false harmonic frequencies related to the aspects that are going to be covered, which are two fundamental concepts for the quality of consumption. This happens because the global value of the electric current establishes the efficiency with which the consumer uses the electrical network. An easily understandable example is an uncompensated electric motor that has a power factor lower than the unit due to the inductive characteristics of its electrical insulation, this causes the appearance of a reactive energy during its operation. Such reactive energy is part of the global energy, which is not directly associated with the work done by the motor, causing the appearance of a parasitic component of the electric current in the conductors of the power supply network. In other words, the final result is a current that is greater than that necessary to satisfy the requirements of the original work. This increase, overloads the power grid, reducing its efficiency or still causing damage to the conductors, transformers and other components of the network.

The same current applies loads that cause the appearance of currents that have false harmonic frequencies in the electrical network. Such parasitic currents and currents are not associated with the work that will be done, such as lighting, heating, power supply for electronic equipment or the like. The measurement process of the present invention considers the integration of the global current with respect to time, simultaneously adding the active, reactive and harmonic fractions that could be generated by the consumer. This naturally leads to a better quality of consumption, since the more efficient the use of the network by the consumer (causes less parasitic currents), the lower the final cost for it.

In addition to the integration of the consumer current, as described above, the process of the present invention associates the adjustment of such integration with the voltage conditions of the power system. This adjustment or correction, as mentioned, can be taken into consideration for four regions or bands related to the operation of the distribution system, as described and indicated below: - a nominal voltage band of the network; - an overvoltage band; - an extended voltage band of the network; and - a band of low voltage. The first region, nominal band, corresponds to the normal limits of variation of the main voltage, which is already incorporated in the calculation of the electrical charges represented by household appliances, lamps and motors. The second region, overvoltage, corresponds to a band that begins at the limit of the nominal band. The third, extended region corresponds to a narrow band located just below the lower limit of the nominal band. In this region the operation of the loads can be executed inefficiently, as in the case of motors / compressors, but without presenting risks for the operation.

The fourth region, low voltage, corresponds to situations where the voltage is lower than those of the extended band, and where the operation of electric charges will be avoided due to a very high inefficiency or a risk situation. Once these regions have been discriminated, the measurement process contemplated herein may add information on the operation of the power system for the integration of the consumer's current. This feature differentiates the present invention from other approaches of the prior art, which use the direct calculation of the electrical quantities of consumption, such as active energy, reactive energy or apparent energy, avoiding the necessary separation between the components of the power supply system and those of the consumer. It also differs from other techniques that consider a large number of electrical quantities at the same time and make the measurement system expensive, making the tariff calculation process a complex and specialized task, as in the case of DE 0 432 386 and US 5,298,856. Before a more detailed description of the measurement process constituting the first aspect of the invention, the basic principles of a second aspect thereof will be described below, which refers to a circuit system for the implementation of meters , using an innovative technology when compared to the technology of the previous technique. One of the innovative concepts used is to allow the operation of electronic circuits in the meters described herein, using an internal source based on the consumer's current, instead of the electrical voltage fed by the distribution network. Based on this quantity - electric current - it is possible to conceive various types of simple and inexpensive equipment, which in spite of that are capable of developing easily and naturally in terms of their functions: - a first example is related to the equipment that only measures and records the electric current taken by the consumer. The amount presented is A.h (Ampere-hours), that is, the integral of the current with respect to time. A device of this type finds application where, for technical and / or economic reasons, there is no need to consider possible voltage fluctuations in the distribution network, whose adjustments will be made in the integral of the current. This case serves the focal point of the invention: small monthly consumers of electricity. The measurement of A.h allows the implementation of a simple and cheap circuit system, extremely resistant, which does not need a separate source or protection devices. Independently of this, it can be elaborated of components that already exist in the market and, even so, the final price of the product is smaller than the conventional measuring devices (W.h) of active energy. - a second example refers to the incorporation into the meter of A.h., previously mentioned, of circuits that take into account variations in the voltage of the electrical network. The measured amount is Av.h, that is, Ampere-hours, adjusted according to the average network voltage, according to the concept of the first aspect of the invention. It can be used where the consumption is large enough to justify it or in places where the voltage is subjected to significant variations; - a third and last example refers to the application of integrated circuit technology with a low operating voltage and very low consumption, such as is used in digital wristwatches and devices such as heart pacemakers. By applying this concept, it is possible to implement an electronic meter capable of operating both an Ah meter and an A ".h meter, or even as a Wh meter, offering communication functions with external command devices and / or reading based on a source, still based on the consumer's current.

Since the meters of the three previous examples are based on the consumer's current, it is not necessary to use external connections or overvoltage protection devices. This eliminates copper connectors, terminals and clamps and it is possible to use a housing capable of accommodating internal components, for example, made by molding or injecting a plastic resin. Such an accommodation is cheap, easy to make and can be dustproof, waterproof and, in general, protected against external bodies. It can also be of reduced weight and dimensions, which simplifies the installation regulations of the electric power distributors. A meter implemented in accordance with such principles does not suffer from the faults that are common in the prior art, such as the disablement of the meters, caused by the oxidation or overheating of the terminals or, in addition, by burning the connecting elements. to the main voltage, due to the rays that fall in the aerial energy lines. BRIEF DESCRIPTION OF THE DRAWINGS The basic concepts and principles of the first and second aspects of the invention have now been explained, the preferred embodiments will now be described with reference to the accompanying drawings, in which: Figure 1 is an explanatory graph showing the voltage supply conditions of an electrical network, illustrating four regions related to the operation of the distribution system; Figure 2 is a schematic diagram of the basic circuit that constitutes the equipment for the measurement of A.h .; Figure 3 is a schematic diagram of an auxiliary circuit that can be added to the circuit of Figure 2, to allow the compensation of errors introduced by the current transformer of the meter, related to the magnetization of the current by the ferromagnetic material used in its building; Figure 4 is a schematic diagram of an auxiliary circuit that can be added to Figure 2, to allow an adjustment of the integration of the consumption current according to the power supply conditions of the mains voltage; Figure 5 is a block diagram of a mode of. the invention that uses an integrated circuit technology with a low operating voltage, low consumption ("micropotency / low voltage"); Figure 6 is an internal block diagram of the integrated circuit shown in Figure 5; Figure 7 shows the typical installation of a meter housing according to this invention; and Figure 8 exemplifies the installation of the meter of Figure 7. DETAILED DESCRIPTION OF THE DRAWINGS Figure 1 shows in a simplified manner a preferred embodiment of the first aspect of the invention, ie, a measurement process based on the integration of the current related to time, adjusted by the conditions of the main voltage fed by an electricity distribution network. The basic elements of the graph of Figure 1 are as follows: x axis: voltage condition of the main voltage. The values established in terms of the percentage, with respect to the nominal value of the operating voltage of the network, are plotted on this axis. Indicating the points related to 80%, 90% and 110% of the nominal main voltage; y axis: correction in the integral of the consumer current. The correction values for each voltage value in the network are plotted on this axis. The indicated points represent the corrections of + 10%, -10%, -30% and 100% The curve defined by the connections AB, BD, DE and FG establish the way of correction according to the four regions of operation of the main voltage, as previously described, that is to say: segment AB, (overvoltage), BD (nominal band ), DE (extended band) and FG (low voltage). Point C corresponds to the condition of the nominal voltage (100%) and, therefore, the zero correction of the current integral. The application of the measurement process that results in the final calculation of a single quantity, denominated in the present Av.h. (consumption current integrated with respect to time, will now be described with an adjustment according to the average of the main voltage of the distribution network). The initial reference point of the process corresponds to point C of Figure 1. This point corresponds to the ideal power supply condition (nominal voltage at 100%) and implies a zero correction in the current integration process. In this case, the consumer with a free consumption of eddy currents, that is, a unit power factor and the absence of harmonic frequencies in the current, will have their consumption measured and charged in an equivalent way in the form of measured active energy. ideal, for example, by a conventional meter of kW.h. As long as the variation of the main voltage remains within the limits of the nominal band (BD segment), the measurement will continue equivalent to this one, which can be done by a conventional active energy meter, provided there are no parasitic current. In other words, for a given current, a variation of ± 10% in the main voltage, which means an equivalent increase / reduction of the active energy supplied by the system, will correspond to a correction of ± 10% in the consumption billing, according to the process of the present invention. In the case of an overvoltage (segment AB), where the service represented by the voltage fed by the distribution system does not provide the consumer with any benefit, as mentioned above, a fixed correction in the measurement process will be used, equivalent to the maximum limit of ± 10% (upper limit for the correction in the nominal voltage band). In this way a reasonable rate is obtained, since there is no increase in the rate when there is no additional benefit for the consumer in an overvoltage situation. In the case of the segment DE (extended band) where the voltage varies between 80% and 90% of the voltage on the nominal line of the network, there is already a decrease in the efficiency of the loads, such as in motors and lamps and, in the case of motors / compressors (refrigerators, air conditioners, etc.) there is an appreciable increase in the eddy currents production of Foucault, due to the reduction in the power factor. Since such phenomena are caused exclusively by the decrease in the supply voltage below the established nominal band, it is reasonable that there is a compensation capable of attending to the worst case of operation of the consumer's load. The segment DE, which has twice the slope, compared to BD (nominal band), aims to satisfy this requirement, establishing, for example, an adjustment of -30% for a variation of 20% in the voltage line. In the case of a voltage drop (segment FG), a region in which there is an accentuated or even dangerous inefficiency for the operation of loads, for example, such as in motors / compressors that may get stuck, causing overheating due to high currents , being able to cancel the consumption record (correction -100%), again a reasonable situation is determined in relation to the food / consumption / tariff. It will be emphasized that the basic concept presented here can be implemented in other ways, such as, for example, altering the voltage variation values and the adjustment that defines the previous segments, without deviating from the basic concept of the present- invention. Referring now to Figure 2, which illustrates a schematic diagram of the basic circuit for the measurement equipment of A.h., it is noted that the electronic components comprising the circuit are as follows: TC - Current transformer. This works as a load current sensor (I; arq? , which provides the circuit with the current having a suitable magnitude for the processing of the electronic circuits and proportional to the load current; DI and D2 - Rectifier diodes. These rectify the secondary elements of TC, working alternately: DI in the middle of the positive cycle and D2 in the middle of the negative cycle; Cl and C2 - Electrolytic capacitors. These are responsible for storing the consumption indicated by the current over time; C3 - Capacitor. This works together with the TC. Its function is to compensate for the errors of the non-linearity of the CT at low currents; SCR - Silicon controlled rectifier. This acts as an electronic switch that is activated to generate a current pulse, activating the cyclometer (counter) due to the discharge of Cl and C2. Its activation is effected by the voltage level at its trigger electrode.

Deactivation occurs with the complete discharge of Cl and C2; AC - A terminal device that acts as a switch controlled by the voltage level. Its function is such that, whenever the voltage between its terminals reaches a wrong value, the SCR is activated; Rl - Carbon Resistor. Its function is to limit the current, protecting DIAC and SCR; C4 - Capacitor. Its function is to desensitize the SCR trigger, preventing it from being activated erroneously due to noise; Group D3, D4, and D5 - Auxiliary circuit. Its function is to facilitate AC drive, ensuring that the latter is always activated by the same amount of current accumulated over time in Cl and C2; Cyclo etro (counter) CT. Electromechanical recorder or meter Its function is to carry out a non-volatile storage of the consumption measured by time. It comprises seven coaxial cylinders, each divided into ten equal parts, where the algorithms are written from 0 to 9, and by a coil that commands the movement of the cylinders due to the current through it. The operation of the circuit is basically as follows: The load current (consumed by the taxpayer) is transformed by the CT, which provides a circuit with a current proportional to it and a reduced value.

This current is then rectified by DI and D2, stored for time in Cl and C2. This causes the potential between points G and H to rise slowly. When this voltage reaches the ignition threshold of DIAC, the latter is activated, which in turn activates the SCR, which subsequently conducts the discharge of C2 and C3, generating a pulsation that activates the cycometer or electromechanical CT counter. This causes the cyclometer to record the occurrence of a pulsation proportional to the consumption of a given amount in A.h. As can be seen in Figure 2, the circuit eliminates the use of a power source or auxiliary surge protection devices, according to which it comprises a low cost and highly resistant solution, manufactured from cheap non-dedicated commercial components. Figure 3 shows a schematic diagram of an auxiliary circuit that can be added to the basic circuit previously described, to compensate for the errors derived by CT due to the magnetization of the current. The electronic components that constitute this circuit are as follows: R2 - Carbon Resistor. This works as a current limiter, protecting the NEON1 lamp and determining its operating current; R3 - Carbon Resistor This establishes the current that one wishes to pass through the I-J windings of the TC; NE0N1 - Neon lamp. This acts as a voltage regulator; and TC - Current transformer. This is the same CT shown in Figure 2, with the addition of another primary winding (IJ), which provides a current approximately equal to the magnetization of the CT core current, compensating for errors that occur when the circuit measures currents Very low;. The operation of the circuit is basically as follows: The main voltage is regulated by the NEONl lamp. Resistor R2, apart from setting the operating current of NEON1, limits it to avoid lamp damage due to overvoltage conditions. Resistor R3 establishes a current in the I-J winding of TC by the lamp voltage of NEON1. This current flows continuously through the I-J winding, feeding the CT core with the necessary magnetization of the current. Figure 4 shows a schematic diagram of an auxiliary circuit that can be added to the basic circuit of Figure -2, to allow an adjustment in the integral of the current based on the variations in the network voltage. The circuit thus configured allows the Ampere-hours measurement corrected by the average of the network voltage (Av.h). The addition of this circuit is done by separating the short circuit E-F (Figure 2) and connecting the points E 'and F' (Figure 4) respectively in the corresponding terminals E and F (Figure 2). The electronic components that constitute this circuit are as follows: D5 and D6 - Rectifier diodes. Act to rectify the alternating voltage of the network; R4, R5, R6, R7 and R8 - Carbon Resistors. They work as voltage dividers; C6 - Capacitor. It acts to reduce the impedance of the alternating current between the points E 'and F', and the sudden variations of the filter in the voltage Vc; NEON2 - neon lamp that acts as a voltage regulator; D7 and D8 - Rectifier diodes; D9 and DIO - Controlled avalanche diodes (Zener); R9 - Carbon Resistor. The operation of the circuit is basically as follows: The voltage of the network is rectified by diodes D5 and D6. The voltage between points H and L is regulated by NEON2. The voltage divider formed by R6 and R8 establishes the voltage at point F '. The voltage divider formed by R4 and R7 establishes the voltage at point E '. Variations in the linear voltage at point E 'are proportionally detected. Since the voltage at point F 'is approximately constant due to the presence of NEON2, the voltage V, (which is in series with the DIAC of Figure 2) also undergoes proportional variations in the variations in the linear voltage, modifying the point of activation of the SCR (Figure 2) and, consequently, the billing rate of consumption as indicated by the cyclometer. When a linear voltage is contained within the limits of the extended band (segment DE of Figure 1), the voltage Vc is slightly negative, due to the division of factors established by the resistors R4, R7, R6 and R8. In this way, the rectifying diode D7 isolates the elements R9 and D9 from the circuit, and the DIO Zener diode does not yet come into operation. The voltage Vc, in this condition, acts on the circuit of Figure 2, so that the variations in voltage result in twice the variation of the proportion of the consumption account. In other words, for a variation of 10% in the extended band, the circuit of Figure 2, with the correction of Vc given by the circuit of Figure 4, there is a variation corresponding to 20% in the consumption account. When the voltage in the network enters the low voltage band (segment FG in Figure 1), the voltage Vc becomes sufficiently negative for the Zener diode DIO to be activated, whose Vc remains at a fixed level corresponding to the variation obtained in point E in Figure 1. This simplification corresponds to changing the segment FG upwards, so that it starts at point E of Figure 1, this includes a possible variation of the concepts of the first aspect of the present invention . When the linear voltage changes to the nominal band (segment BD of Figure 1), the voltage Vc becomes slightly positive, whereby the diode D7 allows the drive of the resistor R9 in the circuit, but the Zener diode D9 still does not is activated In this condition, the voltage V. - accompanies, in a ratio of 1: 1, the variations in the linear voltage. In other words, the circuits of Figures 2 and 4 jointly present, for a variation of 10% in the linear voltage, corresponding variation with the proportion when billing the consumption. When the linear voltage corresponds to the overvoltage band (Segment AB in Figure 1), the voltage Vc is sufficiently positive for the Zener diode D9 to be activated, which establishes a fixed value level Vc. In this case, the circuit of Figure 4 establishes a fixed positive correction in the proportion by counting the consumption by means of the circuit of Figure 2, according to the principle set forth with reference to Figure 1 (segment AB). Figure 5 is a block diagram of an embodiment of the invention, which employs the application of an integrated circuit technology of the micropotency / low voltage type.

Taking into account the concept introduced by the present invention - the quantity that characterizes the electrical consumption is the current taken by the consumer - the equipment can be conceived, as shown in Figure 5, depending for its operation exclusively on the current of the consumer , which, is still capable of handling more than one amount related to electricity consumption. A first step in this direction is the use of a technology, micropotency / low voltage, as is commonly used in the construction of wristwatches and pacemaker for the heart. Circuits of this type employ a source of micropotence which, for its operation, can be based on a minimum amount of electric current circulating in an external circuit. So a single current transformer can provide not only the current that represents the electrical consumption to be measured, but also the power to power the measurement circuit, when the latter is based on a technology - micropotency / low voltage. The measurement circuit can then be established, based on the current provided by the current transformer and a sample of the linear voltage by a voltage detector, in quantities such as Ampere-hours (Ah), Ampere-hours adjusted by the average of the linear voltage (Av.h), according to the principles established in Figure 1, and finally, the active energy (Wh). Since the measurement circuit depends only on the consumer's current for its operation, in the event that the linear voltage detector fails or there is an attempt to fraud when it is switched off intensively, the circuit can continue to operate when considering, for example , that the linear voltage is nominal and the unit of the power factor, with which the consumption will be billed according to the normal power supply conditions of the network. This feature allows the use of housings for the measuring elements according to the invention, which eliminate screws, terminals and load current conductors of the consumer. This is because it does not need to interrupt the consumer's electrical circuit to guarantee the power supply to the internal circuits of the meter, as required in the prior art. Therefore, this invention allows the use of highly reliable low-cost solutions, when compared with those of the prior art. In order to illustrate these aspects, Figures 5 and 6 will be described below in detail. In this mode, the measurement work is carried out by a dedicated integrated circuit, specifically designed to meet the requirements of its function. The dedicated integrated circuit (Cl) 1 will have a very low consumption, this is powered by a micropotence source 2 that takes only the secondary energy of the power from the current transformer, to feed both the integrated circuit 1 and the crystal image liquid (ICL) 3. This image 3 is the element responsible for externalizing the value represented by the consumption measured by the equipment. The current transformer TC is responsible for feeding the integrated circuit 1 with the current sample I proportional to the current that is consumed. The RIO resistor is responsible for feeding the integrated circuit 1 with the sample of voltage V proportional to the linear voltage. In order to understand the operation of the circuit, one must first understand the internal architecture proposed by the dedicated integrated circuit. Figure 6 is a block diagram of the internal architecture of the dedicated integrated circuit 1. The main parts and their functions are as follows: Signal processing block 4 - receives the current and voltage signals. Decide if the measurement will be in A.h., Av.h. or W.h. This is compensated by the deficiencies in the linearity of the current transformer TC and feeds the adjustment to calculate the consumption according to the voltage V; Power supply conditioner block 5. receives the power supplied by the micropotence source 2 and detects power failures Vcc power; Image control block ICL 6 - sends the signals for the externalization of the recorder of a consumption measured in the ICL 3 image; IN / EXT oscillator 7 - responsible for the generation of an internal clock in the dedicated integrated circuit 1; Communication interface block 8 - responsible for the communication between the integrated circuit 1 and the external world through the PC communications gate. This allows the programming of the dedicated integrated circuit 1, making its operation versatile and allows the use of external devices that can implement differentiated rates, remote reading and the like; Controller 9 - responsible for the internal control of the remaining blocks of the dedicated integrated circuit 1. Based on the voltage and current signals - V and I, it establishes the measurement quantities in the form of Ampere-hours adjusted by the voltage V and the wats in hours. If the power conditioning block 5 detects a power failure, the consumption calculation is transferred to the non-volatile memory block 10. Non-volatile memory block 10 - this block, which is capable of storing information about the consumption indefinitely, returns the information to the controller 9 with the return of the power supply, so that normal operation can be restored. The controller 9 is also responsible for inspecting the operation of the Communication Interface and the control blocks of ICL-8 and 6, related to the information groups and the commands changed with the external environment. The actual installation of these blocks is not difficult for a person skilled in the art, the technology per se does not form part of the present invention. Figure 7 shows the typical mode of a housing containing a meter according to this invention, in its Ampere-hours version. As can be seen in Figure 7, the housing 11 can be implemented as a single monolithic part that is water, dust and gas proof, as well as other foreign bodies against which it is protected for operation. Through the holes 12 it allows the power supply of the phase conductor to the consumer as it passes through the housing without interruption. Two holes 13 in the mounting lugs 14 allow a simple and safe installation of the meter. In Figure 8, where it is possible to see a typical installation of the Ampere-hours meter of Figure 7, you can see the passage for the phase conductor that feeds the consumer 15. You can also see that a single conductor is sufficient for the operation of the meter, since it conducts the basic information for the measurement (electric current), the neutral conductor goes directly to the consumer circuit without passing through the meter. Figures 7 and 8 also show the cycometric logger (counter) CT through a suitable window 17 in the housing 11. An observation of the simplicity and the reduced space necessary for the installation is also made, since the driver's passage 15 through the meter allows a compaction of the power supply output of the network (bus-line 9, the power input for the consumer circuit (busway-load) and the usual protection device (switch) 18 in a minimum space It will be understood that only the preferred embodiments of the present invention have been described and that numerous other implementations of the basic concepts of the invention are possible, without departing from the matter in question protected according to the definitions contained in the claims. It is noted that in relation to this date, the best method known to the applicant to carry the practice of said invention is that which is clear from the present description of the invention. Having described the invention as above, the content of the following is claimed as property.

Claims (19)

1. CLAIMS 1. The measurement process for measuring a chargeable electrical consumption of an electrical network, characterized in that it comprises the steps of: a) carrying out a permanent measurement of the consumer's current; b) integrate the value of the measured current with respect to the time until the value (A.h.) is obtained in relation to the electric consumption by the consumer; c) adjust the integration step b) according to the electrical voltage of the network until the adjusted value (Av.h.) is obtained, which is proportional to a preset power consumption unit; and d) calculate the number of pre-established units obtained, in order to obtain the value proportional to the chargeable electric consumption at any time.
2. 2. The process in accordance with the claim 1, characterized in that the correction of step c) is preferably carried out in pre-established proportions according to the voltage deviation bands of the network at the nominal voltage of the network.
3. 3. The process in accordance with the claim 2, characterized in that these deflection bands comprise: - a first nominal voltage band on either side of the nominal voltage of the network; a second overvoltage band; - a third extended voltage band, lower than the first nominal band; and - a fourth band of low voltage, lower than the third band of extended voltage.
4. The process according to claim 3, characterized in that the correction within the first band increases linearly from a first negative value at the lower end of the first band to a first positive value at the upper end of the first band, the correction within the second overvoltage band is constant and equal to the first positive value, the correction within the third extended voltage band increases linearly in a greater proportion than in the first band, from a second negative value in its lower end increases towards the first negative value at its upper end and the correction at the fourth band is constant.
5. 5. The process according to claim 4, characterized in that the correction within the fourth band is 100% negative.
6. The process according to claim 4 or 5, characterized in that the proportion of the linear increase in the third band is twice the proportion of the linear correction in the first band.
7. 7. The process according to claim 5 or 6, characterized in that the first negative value is 10% positive and the first negative value is 10% negative.
8. 8. The electronic electricity meter for measuring an electrical consumption of a power supply network, characterized in that it comprises a circuit without power supply, defined by a current transformer adapted to be associated, as a primary line, with the load line of the consumer, the transformer has a secondary winding adapted to generate a current representative of the load line of the consumer, an integrated circuit connected to said secondary winding to integrate the value of the current in the secondary winding with respect to time, a detector element to detect when the value integrated by the integrated circuit reaches a pre-established unitary value chargeable as a unit of the electrical consumption and a counter element associated with the detector element to add the detected units of the electrical consumption.
9. The electricity meter according to claim 8, characterized in that it also comprises a voltage sensor circuit for detecting the voltage in the consumer supply network and an adjustment circuit for correcting the integrated value as a function of the voltage detected by the sensor.
10. The electricity meter according to claim 9, characterized in that the adjustment circuit determines several adjustment bands with different properties on either side of the nominal value in the mains voltage.
11. The electricity meter according to claim 10, characterized in that the adjustment bands comprise: - a first nominal voltage band on either side of the nominal voltage of the network; a second overvoltage band after the first band; - a third extended voltage band, lower than the first nominal band; and - a fourth band of low voltage, lower than the third band of extended voltage.
12. 12. The electricity meter according to claim 11, characterized in that in the first band, the correction applied to the adjustment circuit in the integrated value, varies according to the first fixed proportion, considering that in the third band, the correction applied by the adjustment circuit varies according to a second fixed ratio that is greater than the first proportion.
13. 13. The electricity meter according to claim 12, characterized in that in the second band, the correction applied by the integrated value adjustment circuit is a percentage that is constant and equal to that of the upper end of the first band.
14. The electricity meter according to claim 12 or 13, characterized in that in the fourth band, the correction applied by the adjustment circuit in the integrated value is a constant negative percentage.
15. 15. The electricity meter according to claim 14, characterized in that the constant negative percentage is -100%.
16. 16. The electronic electricity meter for measuring a chargeable electrical consumption of a power supply network, characterized in that it comprises a current sensor arranged to generate a current representative of the current value taken by the consumer; a voltage sensor for generating a voltage representative of a voltage fed from the power supply network to the consumer; a source of micropotence associated with the current sensor to produce a supply voltage; an image to represent a number of preset units of electrical consumption detected by the meter; and an integrated circuit activated by the supply voltage of a micro power source and arranged to calculate the electrical consumption represented by the units based on the current detected by the current sensor and adjusted according to the variations in the voltage detected by the sensor of voltage.
17. 17. The electronic electricity meter according to claim 16, characterized in that the integrated circuit includes circuit elements to effect the adjustment of the electrical consumption, the adjustment is implemented according to the different bands of variation of the voltage detected by the voltage sensor.
18. The electronic electricity meter according to claim 17, characterized in that the bands comprise: - a first nominal voltage band on either side of the nominal voltage of the network; a second overvoltage band after the first band; - a third extended voltage band, lower than the first nominal band; and - a fourth band of low voltage, lower than the third band of extended voltage.
19. 19. The electronic electricity meter for measuring the electrical consumption of a power supply network, characterized in that it comprises a housing of a plastic material in one piece, having at least one continuous passage for a phase conductor of the consumer; a window for the observation of a meter of units of electrical consumption, the counter is part of a measuring circuit mounted inside the housing; and elements for mounting the housing on a support surface. SUMMARY OF THE INVENTION The present invention describes a process for the measurement of electrical consumption, which is especially suitable for small consumers, comprising the steps of continuously measuring the current of the consumer, integrating the current with time to obtain a value (A.h) related to consumption; adjust the integration according to the network voltage to obtain an adjustment value (Av.h) proportional to a preset power consumption unit; and calculate the number of pre-established units obtained to provide a value proportional to the consumption of chargeable electricity. Preferably, the adjustment is carried out in the integration according to the four voltage bands in the network, in the form of a nominal band on either side of the nominal network voltage, an overvoltage band, a band of extended voltage lower than the nominal band and a low voltage band. Also described is a voltage meter without any power source, which comprises a current transformer (TC) having the consumer load line (15) as primary and secondary lines that generate a representative current in the load line, a circuit connected to the secondary to integrate the value of such current with time, a detector element to detect when the integration circuit reaches a pre-established chargeable unit value of the electricity consumption and a counter element with the detector element to add the consumption units detected. Also disclosed is a housing that is one piece of extremely simple construction.