CZ203899A3 - Method of uniform distribution of electric loading via n-phase distribution network and apparatus for making the same - Google Patents

Abstract

Apparatus and method for uniformly distributing electrical load through the n-phase switchgear. Electric current in each inlet phase (C1, C2 and C3) and in each branch circuit (1-5) is measured by current sensor (16,18,20,42, 44,46,48 and 50). Current sensor outputs monitored in the processor (12), with each branch a multipole switch (22,24,26,28 and 30) is connected to the circuit a conventional circuit breaker (32,34,36,38,40). Each Switch (22.24.26, 28 and 30) allows the connection of a corresponding branch circuit (1-5) for each inlet phase (C1, C2 and C3) and disconnect branch circuit (1-5) from all η phases (C1, C2 and C3). The processor (12) regularly monitors the streams passing through each inlet phase and under load conditions junction circuits (1-5) sets switches (22,24,26,28 a 30) even distribution of branch circuit loads (1-5) over all three feeder phases (C1, C2 and C3).

Description

Technical field

The present invention relates to a method and apparatus for uniformly distributing electric loads in a three-phase power grid.

BACKGROUND OF THE INVENTION

At present, many residential and commercial facilities receive all three phases of the electricity grid provided by electricity companies or utility companies with connections. In a typical three-phase distribution system, each phase feeds one or more branch circuits. Deciding which branch circuit (s) to connect to each of the three supply phases is usually made during the design or construction of an enterprise, so that once the construction is complete, it is difficult to make any changes. For example, in a residential building, different tap circuits can power the kitchen, living room, bedroom, etc. In a commercial area, different tap circuits can power machines, offices, etc. Often, there is a problem of how to distribute the electricity supplied by electrical companies evenly from the three supply phases to all branch circuits. Often, over time, the burden on a particular business varies, sometimes fundamentally. Some branch circuits will be more heavily loaded and others less heavily, for example, depending on the relocation of machines on the factory floor or in households with the addition of high-power appliances (ie electric refrigerators).

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9 «99 stove, microwave etc.). Therefore, the load on each of the three supply phases will also change by varying the load on the branch circuits. The three-phase network, which was initially evenly balanced, will become unbalanced over time.

One solution to this problem is to allocate each branch circuit to one supply phase to achieve a uniform load on all three phases by physically connecting each branch circuit. The disadvantage of this solution is that expensive wiring of electrical cabinets and distribution panels is required each time there is an imbalance between all three phases, which can happen frequently. Another disadvantage is that switching usually requires a power cut, which can cause problems for customers. Moreover, such a solution is merely a coarse load balancing mechanism for all three feed phases. It is not possible to repeatedly monitor the power consumption at each phase and branch circuit. Changes in electrical loads that occur from hour to hour and from minute to minute may be high enough to induce an imbalance between all three supply phases, and remain undetected.

SUMMARY OF THE INVENTION

The above disadvantages are overcome by the method of uniformly distributing the electric load across all three phases of the three-phase grid and the apparatus for carrying out the method according to the present invention.

According to this, the three-phase distribution system comprises first, second and third current sensors connected to the first, second and third phases, respectively a three-phase power grid, first, second and third current sensors for measuring the current flowing through the first, second and third phases. optionally, a plurality of switches, each switch being connected to one of a plurality of tap-off circuits, each of which is 4 • * 4 · · 4 ·

4 4 4 4 4 4 4 · 4 • 4 · * · · * • 44 44 · 44 4444 44 44 of switches is designed to connect one of the phases, ie the first phase, the second phase or the third phase to one of the tap circuits, a plurality of current sensors, each current sensor being connected to one of the tap circuits, a plurality of current sensors for measuring electrical current flowing through each of the plurality of tap circuits, and a processor connected to the first, second and third current sensors, , a processor for controlling a plurality of switches such that the electrical current of the first, second and third phases does not exceed a predetermined threshold.

Furthermore, according to the present invention, the three-phase load distribution system comprises first, second and third current sensors connected to the first, second and third phases, respectively a three-phase power distribution network, first, second and third current sensors for measuring the current flowing through the first, second and third phases. or a plurality of switches, each switch being connected to one of a plurality of tap circuits, each switch being designed to interconnect one of the phases, i.e., the first, second, or third phase to one of the tap circuits, a plurality of current sensors each connected to one of the tap circuits, a plurality of current sensors to measure the electrical current flowing through each of the tap circuits, and a processor connected to the first, second and third current sensors, a plurality of switches and a plurality of current sensors, a processor for controlling the switches such that the differences between the electrical currents flowing through each pair of the first, second and third phases, or their ratios, do not exceed a predetermined threshold value.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is further described by way of example with reference to the accompanying drawings, in which:

Fig. 1 shows a block diagram of a three-phase embodiment according to the present invention;

Fig. 1B is a block diagram of a single-phase embodiment of the present invention;

Fig. 2 is a block diagram of a general embodiment of the present invention;

Fig. 2B illustrates a simple implementation of the adder circuit 52 and the rectifier 54 of Fig. 2, combining two functions in one block, a three-phase rectifier 524;

Fig. 2C shows a diagram of a stable DC / AC converter converter;

Fig. 2D is a diagram of an improved stable DC / AC converter converter;

Fig. 2E shows a three-phase rectifier and an improved stable DC / AC converter with coil added to increase the input power coefficient;

Fig. 2F replaces the coil of Fig. 2E with a high-power gain switching controller to further increase the input power increase coefficient;

Fig. 3 is a block diagram of an embodiment of the present invention combining features of the systems of Figs. 1B and 2F and further adding transmission capability;

Figure 4 is an alternative to the embodiment of Figure 2 of Figure 2B;

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Fig. 5 shows a digital electricity meter connected to the processor, and Fig. 5B shows the function of the hardware for measuring electricity.

DETAILED DESCRIPTION OF THE INVENTION

The principles and functions of the solution of the present invention may be better understood with reference to the figures and the accompanying description.

A block diagram of an embodiment of the device 10 according to the present invention is shown in Fig. 1. A three-phase electric current with phases 1 1, 2 2, 3 3 is supplied by electrical undertakings. Phases 41, 12, 13 are protected against current overload by the main circuit breaker 14. The output of the main circuit breaker 14 is provided at a service connection to a residential or commercial building. The current sensors 16, 18, 20 measure individually the current flowing through the U, 12, 13 phases. The outputs of the current sensors 16, 18, 20 are monitored by the processor 12. The processor 12 may be any suitable computing element such as microprocessor, microcontroller, personal computer etc. .

The output of each of the three phases from the main circuit breaker 14 is an input to a series of multi-pole switches 22, 24, 26, 28, 30. Each switch has four input terminals. Three input terminals are provided for each of the three supply phases. In addition, a fourth terminal is provided that is not a terminal (that is, not connected to anything). The outputs of the switches 22, 24, 26, 28, 30 are individual inputs to a series of circuit breakers 32, 34, 36, 38, 40. The control signals CQNT1, CONT2, CONT3, CONT4, CONT5, which are output from the processor 12, individually determine the position of switches 22, 24, 26, 28, 30. Circuit breaker outputs 32, 34, 36, 38, 40 before being fed into the circuit. each of the five tap circuits, passing through a series of current sensors 42, 44, 46, 48, 50. Each of the five tap circuits has a neutral zero • 9 • 4 · · *

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444 44 444 4444 44 4 · wiring Ν. The current measured by the current sensors 42, 44, 46, 48, 50 is monitored by the processor 12.

Operation of the device 10 is centered around the multi-pole switches 22, 24, 26, 28, 30. Using the device 10, each tap circuit to be covered is coupled to a respective switch, tap circuit breaker, and current sensor. FIG. 1 shows a load balancing system covering five branch circuits. However, the solution of the present invention can easily be used to cover any number of tap circuits by simply adding a sufficient number of components.

The processor 12 periodically receives the output of the current sensors 16, 18, 20, which measure the current flowing through each phase of the supplied three-phase electric current. The processor 12 also monitors the output of the current sensors 42, 44, 46, 48, 50, which measure the current flowing through each tap circuit. The time between successively received data from the current sensors is in the order of milliseconds or tens of milliseconds and is a function of the software controlling the processor J2. Data received in each cycle is not immediately discarded. A limited number of most recent sets of received data is stored in memory, which may be external or internal memory of processor 12.

The processor 12 is suitably programmed to periodically receive data from all current sensors so as to be able to monitor the load on each of the three supply phases and on each tap circuit. When the measured current at any phase exceeds a fixed percentage (for example, 90%) of the set upper limit, the processor 12 will program switches 22, 24, 26, 28, 30 such that the total load is equally distributed across all three supply phases . Because the load on each tap circuit is known, the processor 12 can redistribute the load to the tap circuits so that the load on each phase is approximately equal. As soon as a new switch is set, the processor J2 sends commands to the control lines CONT1, CONT2, CONT3, CONT4, CONT5 individually to the switches. switches 22, 24, 26, 28, 30 to switch them.

In the operation of the JO device, it is possible that the load on a single branch circuit is increased to a level that exceeds the maximum allowable current. The processor 12 responds to this overcurrent condition by reprogramming the switch corresponding to the respective tap circuit to its open position. In this position, the tap circuit is electrically disconnected from all three supply phases. In addition to the overload protection provided by the processor 12, conventional branch circuit breakers 32, 34, 36, 38, 40 are also provided for overcurrent protection for each branch circuit. The device 10 may also perform a function that conventional circuit breakers cannot provide. The processor 12 may suitably be programmed to anticipate potential overload before it occurs by monitoring the rate of current rise in each branch circuit and each supply phase. Therefore, a potential interruption of the electricity supply due to exceeding the current limit on the supply phase can be foreseen and prevented before it occurs.

The switches 22, 24, 26, 28, 30 may use relays or semiconductor switches (e.g., triacs, silicon controlled rectifiers, etc.) as their basic switching elements. Each switch decodes the corresponding control signal received from the processor 12 and connects its output to one of the switches. Switches 22, 24, 26, 28, 30 can connect their output terminals to any supply phase fast enough so that a device or appliance connected to the corresponding tap circuit does not detect any noticeable interruption and therefore are not adversely affected.

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The processor 12 is powered by a phase and a neutral line N from a three-phase supply. However, the processor 12 may be powered from any of three supply phases. The setting of the upper current limit can be supplied to the processor 12 by known methods in the art. For example, the upper current limit may be hard coded in read-only access memory and may be set by an external switch, external computing device, etc.

Although the description of the above embodiment has been made with respect to the three-phase system, it should be noted that the system of the present invention may be embodied as an n-phase system, for n arbitrary. As a single-phase system 1000, the system is shown in FIG. 1B. It can be seen from the comparison of Fig. 1 and Fig. 1B that in Fig. 1B two feed phases are omitted. The blocks, functions and labels are all the same. The only difference between a single-phase and two- or more-phase system is that switches 22-30 are merely capable of connecting or disconnecting their respective tap-off circuits to one phase and not a change of tap-off circuit from one phase to another phase. Thus, in a single-phase system, it is possible to select which circuit to disconnect in the event of an overload in the system, not to select which phase of the rest circuit will be reconnected. Therefore, the present invention can be applied to any number of phase power sources, but most conventional cases envisage three and one phases, as shown individually in Figures 1 and 1B.

A second embodiment of the present invention, shown in FIG. 2, is intended to distribute the load evenly over each phase of a three-phase power distribution network. Each phase L1, elektrickéhofc2, β of the three-phase electric grid is an input to the addition circuit 52 for adding up the electric energy. The adder circuit 52 receives each feed phase and combines its current and power to produce a single total sum output. The output of the adder circuit 52 is the only AC voltage, the magnitude of the current being approximately equal to the sum of the current sizes of all three feed phases.

The output of the addition circuit 52 then becomes an input to the rectifier 54. The rectifier 54 rectifies the AC output of the addition circuit 52 to a substantially DC level. The ability of the rectifier 54 to rectify the current must be sufficient to cover all the needs of all tap circuits to be covered by the JO device.

The output of the rectifier 54 is an input to the AC generator 56. An AC generator 56 generates a single phase AC voltage from the DC voltage output of the rectifier 54. An appropriate voltage and frequency (e.g., 120 V, 60 Hz for the United States) is generated for the appropriate location at which the JO device is to operate.

The output of the AC generator 56 is input to the circuit breakers 32, 34, 36, 38, 40 covered by the device 10. The branch circuits are supplied with electricity from the outputs of circuit breakers 32, 34, 36, 38, 40. Although five tap-off circuits are shown in FIG. 2, the device 10 can cover any number of them, provided that the elements have sufficient current rating for the combined load of all tap-off circuits.

The actual load distribution in the JO device occurs at the adder circuit 52. No matter how the load in each branch circuit increases or decreases, it automatically distributes evenly across all three feed phases. For example, if the load on one branch or branch group increases by 30%, the corresponding load on each input phase is increased by 10%. Since the input phases can always be represented by an equivalent low-impedance current source, which are identical to each other, ··· · · · · ·

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44 ··· 4 · ·· then, when the load on the summation circuit 52 increases by 30%, this increase occurs evenly across the three feed phases.

The advantage of this second embodiment over the first embodiment is that it is less complex, but may be more expensive, since expensive components must be used for the summation circuit 52, the rectifier 54 and the AC generator 56 to be capable of handling higher current currents.

Giant. 2B illustrates a simple implementation of the adder circuit 52 and the rectifier 54 of FIG. 2, combining the two functions in one block, a three-phase rectifier 524. FIG. 2B also shows an optional filter capacitor 58.

It is important to note that the system of Figures 2 and 2B is not battery backed up or treated to interrupt the power supply, but rather balances the load caused by the single-phase output circuit as well for the three input phases using the addition circuit 52. as a result, the load on the single-phase output circuit is instantly completely evenly distributed across all three phases of the input three-phase circuit, even without the load balancing processor J2 of Figure 1. Therefore, the system of Figures 2 and 2B represents An improved embodiment of the system according to the present invention over the embodiment of Fig. 1. Therefore, a battery-backed power distribution system as described in the prior art by Fiorina in US 5 477 091, which is a completely single-phase system comprising lohovací battery can not ensure a clear and load balancing functionality as the embodiment of FIG. 2 and FIG. 2B the present invention.

Further, the AC generator 56 may be implemented as a stable converter, DC / AC converter or DC / AC converter, without deviation.

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4 to 4, as an AC generator, it is also a rotary converter. Therefore, known stable transducers can be used. An example of a schematic of a stable DC / AC converter is shown in Figure 2C. The DC input 213 from the adder rectifier 524 powers the DC / AC inverter 200, generating a rectangular AC signal at output 211 which, after filtering through low-pass filter consisting of inductors 208 and 209 and capacitor 210, transforms into sinusoidal AC output 212. consisting of a pair of switching transistors 201 and 202, the collectors of which are connected to the ends of the primary winding 207a of the core saturation transformer 207. The DC input is used from the center terminal of the base to interconnect the emitters of transistors 201 and 202. The polarization in the direct direction is made by transistors 201 and 202 and resistors 203 and 204, which are individually bridged for alternating current capacitors 205 and 206. winding 207d to the base of transistor 202. The oscillator is astable with a frequency depending on the transformer design. This is a rough implementation of this type of circuit and is given as an example to illustrate the basic function. It is known as its Royer oscillator after its inventor. This circuit was published in Royer G.H., Switching Transistor AC / DC Converter, Trans AIEE, July '55.

The improved inverter 2000 embodiment of Fig. 2D uses a non-saturation transformer 207 and connects the saturation feedback transformer 2070 to the base circuit. The saturation base feedback transformer then determines the DC / AC operating frequency of the inverter. This circuit does not control the output voltage. In both circuits, the rectangular secondary output of the inter-peak voltage depends on the DC input voltage and the output frequency depends on the DC input voltage as well as the saturation transformer characteristics. This improved inverter was published in Jensen J.L., Improved Rectangular Oscillator Circuit, Trans. IRE, Vol. CT-4 3, Sep '57.

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The system of FIG. 2 can then be implemented inexpensively by combining the three-phase rectifier of FIG. 2B with the inverter of FIG. 2C or FIG. 2D. This three-phase rectifier balances the load equally with each of the three supply phases without the required IT equipment.

The system of Fig. 2, Fig. 2B, Fig. 2C or Fig. 2D can be used equally well for a two-phase system or a system with more than three phases, for example an n-phase power distribution system. Filter capacitor 58 and low pass filter 208, 209 may be included to provide a sine output 212 depending on the desired output spectrum of the powered circuitry.

The system of Fig. 2, Fig. 2B, Fig. 2C is especially suitable for small installations, say small plants. In this case, the use of this embodiment of the present invention will also help in the event of an input power factor correction problem, since for all different motor loads and other indirect resistive loads, the AC input will be replaced by the input rectifier circuit. It is possible that by omitting capacitor 58 or using very low noise filtering capacitance and inductance of the primary winding 207a of transformer 207, the power coefficient can be improved even without installing this load balancing circuit. This is because the capacitor input rectifier provides a power coefficient of about 0.6, while the infinite inductor rectifier ideally provides a power coefficient of about ninety percent. The improved DC / STR inverter of FIG. 2D with a non-saturation collector transformer 207 and a separate base saturation winding 2070 could further improve the input power coefficient. Finally, the third variant is a double-acting current converter in which a large coil is connected in series with a DC source from the input to the transformer center 207. This would cause an increase in inductance in the rectifier circuit and a further increase in the input coefficient

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• 4 44 power. A high power coefficient is important for powering companies and businesses, as it represents potential savings in the cost of power distribution equipment, as is well known. Giant. 2E illustrates a system 10 comprising a three-phase rectifier 524 and an improved stable DC / AC converter 200 with a coil 2071 coupled to increase the input power coefficient. The pure resistive load has a power factor of 1.0. The phase current load caused by the non-resistive load and the non-linear load breakdown limits this power coefficient and results in an increase in the electrical equipment cost, causing the inability to connect electricity to the customer's site.

Although stable inverter circuits are technologically very old, they represent the simplest and least expensive implementation. Newer double-acting controllers with feedback control circuits and non-saturation transformers can be used to create stable transducers with independent output voltage and frequency. The realization of such inverters operating with low-voltage battery power is well known. The design of such circuits for higher input voltages is uncomplicated and less difficult than in the case of a low voltage input.

Giant. 2F replaces the coil embodiment 2071 of FIG. 2E by the high power coefficient switching regulator 5242 to further increase the input power coefficient. The 5242 booster can use a Unitrode Integrated Circuits UC 1854 control unit. This section and its application is well documented in the Unitrode literature entitled Product and Applications Handbook '93 -'94, IC850, Unitrode Integrated Circuits Corporation, 7 Continental Boulevard , Merrimack, NH 03054, United States, (603) 424-2410 FAX: (603) 424-3460. Block 5242 provides a controlled DC voltage output of 5244 k DC / AC inverters _IO, eliminating φ · · · * · * φ ♦

0 · 0 0 * · • 00 · 0 000 000 »00 ·· One case of AC output frequency, as well as fixing the output amplitude of the DC / AC converter JO. The Choldup 5243 capacitor provides a charge memory that allows the DC / AC converter JO to continue providing AC output 211 for a few milliseconds after transient low voltage on the input line. This is done at the time of periodic load shedding if a low input voltage signal is detected by the amplifier 5242, which happens quite often. UC 1854 and other similar high power coefficient controllers are capable of providing input power coefficients for an n-phase power source greater than 0.99 when operating in a normal single-phase system. With the three-phase input of Fig. 2F, the same circuit would achieve an increase in the input power coefficient, since the error source known as the "peak breakdown" described in Unitrode literature would not be used when using a control unit with an n-phase power source. This is because the auxiliary phases do not allow the controller's minimum input voltage to increase the high power coefficient instantaneous drop to zero, such as with a single-phase two-way bridge rectifier, since the auxiliary phases fill the remainder between two half cycles of the single-phase input. This peak breakdown is analogous to the overload in the amplifiers and is eliminated by filling the ripple, since the input voltage reaches a problematic low range near zero.

This control unit 1854 and method are described in the following Unitrode IC literature:

(1) UC 1854/2854/3854 High Power Factor Preregulator (1854 Data Sheet) (2) U-134, UC3854 Powered Factor Correction Circuit Design (3) DN-39D, Optimizing Performance in UC3854 Power Factor Correction Applications (4) DN-41, Current Transformer Ranges (5) U-140, Average Current Control Mode of Switching Power Supplies.

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In summary, the method of Fig. 2, etc., and the system of equalizing the electric load on the n-phase power source comprises the following steps:

rectifying said n-phase power source to form a DC voltage source:

connecting said DC voltage source to a DC / AC inverter to generate an AC output voltage;

generating said AC output voltage from a DC voltage;

connecting an AC load to said AC output voltage supplying said AC load with an AC output;

wherein said output AC current is reflected back through said DC / AC inverter as a DC load current to said DC voltage source and wherein said DC load current is fed back via said n-phase rectifier as an input AC load current to said AC phase power source, wherein the input AC load current is uniform across all n phases of said n-phase source by said n-phase rectifier;

balancing said alternating output current at said n phases of the n-phase power source.

Fig. 3 is a block diagram of an embodiment of the present invention combining the features of the systems of Figs. 1B and 2F and other added communication transmission capabilities, e.g., with the utility or customer via communication lines, e.g., modem 3001. 1B and the rest of the system of FIG. 1B, providing automatic load balancing as well as a high power coefficient as described above. The system of FIG. 1B is represented here as an n-unit, denoted by the circuitry 1001 ... 1002, which represent each unit of circuitry. to every change of branch circuits. These tap-off units are connected to the processor 3012, the same as the processor J2 in FIG. 1B, and not just controlled by the processor 3012 to limit the maximum load on the n-phase main circuit by limiting the maximum load current provided by the DC / AC inverter. . In addition, processor 3012 has capabilities that will be described below. Modem 3001 is connected by a two-way data bus 3004 to the processor 12. Preferably, the modem 3001 is connected via an RJ11 interface 3002 to the central telephone exchange 3003. The modem 3001 provides communication, for example, with a utility or customer.

In addition, the programmed control of the processor 12 provides the connection or disconnection of the load; tapping circuits, depending on current measurement by sensors 18 and 42m, processor 3012 also provides programming of additional load management as a function of time, such as time of day or day of the week. Also, load failures in the event of overloading and load switching can be performed according to the priorities programmed by the consumer in the processor 3012. Thus, the electricity consumer can, for example, control the operation of the device at its location, even in its absence. Further, the processor 3012 can report data to the utility via modem 3001. Still further, electrical companies can query the processor for issues related to each phase load in the n-phase system of Fig. 1 or the load on each branch circuit in each embodiment shown in FIG. images. Also, the utility or customer may issue processor commands such as to connect or disconnect the load, for example, to manage the load easily by the customer via modem 3001 and processor 3012, and the utility or customer may reprogram the processor 3012 via modem 3001. mobile • 44

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Giant. 4 illustrates an alternative embodiment 5400 of the combination of blocks 52 and 54 of FIG. 2, for a three-phase system, as an example of an n-phase system where n is 3. In FIG. 4, each phase is first rectified in rectifiers 401-403 where each rectifier output. serves as an input to the power factor correction modules 405-407 as described above, for example using a UC 1854 or a similar control unit. The power factor correction module outputs n are coupled together and connected to capacitors 409, which provide a DC output 410. The power factor correction module N has a common load bus connection 408, for example, reported in Unitrode literature with respect to their UC1907 Load Share Controller IC and with respect to switching controllers such as the UC1842. The purpose of the load bus is to ensure that each power factor correction module provides a uniform proportion of the current load as any other module, plus or minus, say, 10% or less.

An advantage of the embodiment of FIG. 4 over the embodiment of FIGS. 2 and 2B is that the embodiment of FIG. 4 will surely provide improved load balancing at n phases and an improved power coefficient for each of these n phases.

Giant. 5 illustrates the additional connection of the digital energy meter 5001 to the processor 3012, such as that shown in FIG. 3. The digital energy meter 5001 is a digital kW / hour meter that records total electricity consumption. The processor 3012 has an added connection 3004 to a modem 3001, which is preferably connected via an interface 3002 to a telephone exchange line 3003. With this arrangement, the electrical energy consumed by the consumer equipment is available through the processor and communication lines for transmission to the location of interest, e.g., the main power company.

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In another embodiment, implicitly included in Figure 3, the current sensors 18 and 42n are continuously monitored by the processor 3012, and in conjunction with simultaneous voltage measurements at the current sensors, instantaneous power consumption can be calculated, as is known. It can be continuously added up, integrated in the processor 3012 and maintain the total power consumption of the device. The necessary hardware for each electrical power measurement is shown in Fig. 5B, showing a current sensor 518 with output 5181 to processor 3012 and a voltage sensor 5189 with output 5189V to processor 3012. Thus, the function of digital meter 5001 can be incorporated into the system of Fig. 3. and the like in an n-phase system such as that shown in FIG. 1.

The function of a digital electricity meter, whether implemented as a tool of Fig. 5 or implicitly as in Fig. 3, as described above, may be useful in any system described herein, even without communication lines, to provide additional additional parameters for use in control. load.

Although the invention has been described with respect to a limited number of embodiments, it will be apparent that many modifications and other applications may be practiced within the scope of the invention. As an example, the n-phase design is usually meant as three-phase, ie for n = 3. Generally, the number of phases is not limited to three phases, but may be any number of phases. Furthermore, any form of communication transmission lines may be used to exchange information between the customer location and the utility.

Claims (10)

PATENT CLAIMS 1. A three-phase distribution system for evenly distributing an electric load existing on a plurality of tap circuits to a three-phase distribution network, comprising: first, second and third current sensors connected individually to the first, second and third phases of the three-phase power distribution network, said first, second and third current sensors for measuring the electrical currents flowing through said first, second and third phases respectively; a plurality of switches, each of said switches connected to one of the plurality of tap circuits, each of said plurality of switches for connecting any of said first, second, or third phases to one of the plurality of tap circuits; a plurality of current sensors for measuring electrical currents flowing through each of said tap circuits; each of said current sensors connected to one of a plurality of tap circuits; and a processor connected to said first, second and third current sensors, said plurality of switches and said plurality of current sensors; said processor for counting, (a) the differences between said electric currents flowing through each pair of said first, second and third phases and (b) the ratios of said electric currents flowing through each pair of said first, second and third phases; said processor for controlling a plurality of switches such that a function selected from the group consisting of (a) differences between and (b) ratios of said electric currents flowing through each pair of 9 9 9 9 9 9 • • 99 999 9 999 9 9 9 9 p 9,999,999 9 9 9 9999 · 9 · 9 of said first, second α third phase shall not exceed a predetermined threshold; said processor counting alternate tap combinations to be connected by said switches to said phases and said processor controlling the reconnection of said tap branches by said switches to phases so that the function does not exceed said threshold value. 2. At least a single-phase load distribution system for evenly distributing the electrical load existing on a plurality of branch circuits on at least a single-phase power distribution network, comprising: at least one current sensor connected individually to the at least one phase of the at least one-phase power distribution network, said at least one current sensor for measuring electrical currents flowing through the at least one phase; a plurality of switches, each of said switches connected to one of the plurality of tap circuits, each of said switches for connecting any at least one phase to one of the plurality of tap circuits; a plurality of current sensors for measuring electrical currents flowing through each of the plurality of tap circuits; each of the current sensors connected to one of the plurality of said tap-off circuits; and a processor coupled to said first, second and third current sensors, said plurality of switches and a plurality of current sensors; said processor for counting (a) the differences between the electric currents flowing through each pair of the at least one phase, and (b) the ratios of said electric currents flowing through each pair of the at least one phase; 9 9 9 9 9 9 9 «9 * 99 ··· 9 9 9 9 9 9 · 999 99 999 * 9 * 9 9 · * · said processor for controlling a plurality of switches such that a function selected from the group consisting of (a) differences between and (b) ratios of said electrical currents flowing through each pair of at least one phase does not exceed a preset a threshold value; said processor counting alternative tap combinations to be connected by said switches to said phases, and said processor controlling the reconnection of said tap branches to the phases so that the function does not exceed said threshold value. 3. A three-phase load distribution system for evenly distributing the electrical load existing on a plurality of branch circuits to a three-phase power distribution network, comprising: first, second and third current sensors connected individually to the first, second and third phases of the three-phase power distribution network, said first, second and third current sensors for measuring the electrical currents flowing through the first, second and third phases respectively; first, second and third circuit breakers connected individually to the first, second and third phases; a plurality of switches, each of said switches connected to one of the plurality of tap circuits, each of the switches for connecting any of said first, second, or third phases to one of the plurality of tap circuits; a plurality of circuit breakers, each connected to one of the plurality of branch circuits; a plurality of current sensors for measuring electrical currents flowing through each of said tap circuits; each of said current sensors connected to one of a plurality of tap circuits; a processor for controlling the switches such that the electrical currents flowing through each of said first, second and third phases do not exceed · 44 ♦ · · in b · 4 * 4 4 · 4 · 4 · pre-set threshold value; said processor connected to the first, second and third current sensors, said plurality of switches and said plurality of current sensors; and a communication link connected to said processor for communication. The system of claim 1, further comprising a communication link coupled to said processor for communication. The system of claim 2, further comprising a communication link coupled to said processor for communication. 6. A three-phase load distribution system for evenly distributing the electrical load existing over a plurality of branch circuits on a three-phase power distribution network, comprising: first, second and third current sensors, connected individually to the first, second and third phases of the three-phase power distribution network, said first, second and third current sensors for individual measurements of electric currents flowing through the first, second and third phases; a plurality of switches for receiving and decoding corresponding control signals, each of said switches connected to one of the plurality of tap circuits, each of said switches for connecting any of the first, second, or third phases to one of the plurality of tap circuits; a plurality of current sensors for measuring electrical currents flowing through each of said tap circuits; each of said current sensors connected to one of said plurality of tap circuits; a processor for controlling said plurality of switches such that the electrical currents flowing through each of said first, second and third phases do not exceed a predetermined threshold; said processor connected to the first, second and third * 4 a current sensor, said plurality of switches and plurality of current sensors; and a communication line coupled to said communication capability processor further comprising a digital electricity meter function, said digital electricity meter enabling measurement of electrical energy, said digital electricity meter selected from the group consisting of (a) a digital kW / hour meter for recording total electricity consumption and (b) a combination of a voltage sensor with said current sensor, said voltage and current sensors having outputs coupled to a processor for calculating electricity metering selected from the group consisting of instantaneous consumption and total power consumption, said electricity meter for processing additional parameters for use in control a load meter and said electricity meter for processing the electricity consumed by the consumer equipment via said communication link. The system of claim 3, further comprising a digital electricity meter selected from the group consisting of (a) a digital kW / hour meter for recording total electricity consumption, and (b) a combination of a voltage sensor with said current sensor, said voltage and current sensors having outputs coupled to said power metering processor selected from the group consisting of instantaneous power consumption and total power consumption, said power meter for processing additional parameters for use in load control, and said power meter for processing power consumed by the devices of the customer via the communication line. in · ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft ft The system of claim 1, further comprising a digital electricity meter, said digital electricity meter, said digital electricity meter selected from the group consisting of (a) a digital kW / hour meter for recording total electricity consumption, and (b) a combination a voltage sensor with said current sensor, said voltage and current sensors having outputs connected to said processor for calculating electricity metering selected from the group consisting of instantaneous power consumption and total power consumption, said power meter for processing additional parameters for use in load management. 9. At least one-phase load distribution system for evenly distributing the electrical load existing on many branch circuits on at least a single-phase power distribution network, comprising: at least one current sensor connected to the at least one phase of the at least one-phase power distribution network, said at least one current sensor for measuring the electrical current flowing through the at least one phase; a plurality of switches for receiving and decoding corresponding control signals, each of said switches connected to one of the plurality of tap circuits, each of said plurality of switches for connecting any at least one phase to one of the plurality of tap circuits; a plurality of current sensors for measuring electrical currents flowing through each of said tap circuits; each of said current sensors connected to one of a plurality of tap circuits; and a processor for controlling said plurality of switches such that the electric currents flowing through each at least one phase are: Φφ φφ does not exceed a preset threshold; said processor coupled to the at least one current sensor, said plurality of switches and said plurality of current sensors, further comprising a digital electricity meter, said digital electricity meter, said digital meter selected from the group consisting of: (a) a digital kW / hour meter for recording total electricity consumption; and (b) a voltage sensor-current sensor combination, said voltage and current sensors having outputs connected to said power metering processor selected from the group consisting of instantaneous consumption; total power consumption, said power meter for processing additional parameters for use in load management. The system of claim 2, further comprising a digital electric power meter, said digital electric power meter with an electric power measuring capability selected from the group consisting of; (a) a digital kW / hour meter for recording total electricity consumption; and (b) a combination of a voltage sensor with said current sensor, said voltage and current sensors having terminals connected to said processor for calculating electricity metering selected from the group consisting of instantaneous consumption and total electricity consumption, said meter for processing additional parameters for use in load management.