RussianPatents.com

Method to control static stabilised sources of ac voltage operating in parallel for common load in case of its asymmetry. RU patent 2472269.

IPC classes for russian patent Method to control static stabilised sources of ac voltage operating in parallel for common load in case of its asymmetry. RU patent 2472269. (RU 2472269):

H02J3/46 - Controlling the sharing of output between the generators, converters, or transformers

Another patents in same IPC classes:

Method to control static stabilised sources of ac voltage operating in parallel for common load / 2472268
Instantaneous value of common voltage is measured, as well as instantaneous values of output currents of sources, they are converted from a three-phase abc-system of coordinates into a rotary double-phase dq-system of coordinates, reference signals are generated for d- and q-components of common voltage, signals proportional to d- and q-components of common voltage, signals proportional to d- and q-components of currents of sources, the first and second differential signals, the first and second signals of comparison by means of integration of appropriate first and second differential signals, d- and q-components of a control signal are generated, modulating signals are generated by reverse conversion into a three-phase abc-system of coordinates, one of parallel operating sources is selected as master, and other ones - as slave, besides, the first and second differential signals of a master source are generated by subtraction of signals, proportional to d- and q-components of common voltage, from reference signals, for master sources the first and second differential signals are generated by subtraction of a signal proportional to d- and q-components of its current from a signal proportional to d- and q-components of the master source current, and the specified d- and q-components of control signals are generated by summation of signals of comparison and signals proportional to d- and q-components of currents of sources.

Aircraft power controller / 2464204
Invention relates to power engineering and may be used in power controller 1 design to control aircraft hydride power source. Power controller 1 allows measuring power demand of consuming hardware 2. Said device 1 allows determining first operating characteristic of first power source 3 and second operating characteristic of second power source 4. First power source 1 and second power source 4 serves to generate first and second required portions of necessary demand.

Method to control static stabilised sources of ac voltage operating in parallel for common load in case of its asymmetry / 2460194
In a control method instantaneous voltage values on a common load and output currents of sources are converted from a three-phase abc - system of coordinates into a double-phase dq-system of coordinates, control signals are generated to stabilise parameters of voltage of direct sequence on the common load and to distribute load current of direct sequence between sources. Control signals are converted from the double-phase dq - system of coordinates into the three-phase abc - system of coordinates, zero sequences of source currents are defined. For each source difference signals of zero sequence currents of only two sources are generated, a final number of harmonic components is extracted from them with a higher amplification ratio, modulating signals are generated in accordance with the invention formula.

Method to control static stabilised dc voltage sources operating in parallel into common load / 2381609
Invention relates to electrical engineering and can be used in organising electric power generation systems or uninterrupted power supply systems with sources connected in parallel into common load. Proposed method comprises measuring instantaneous voltages at common load and source instantaneous currents, obtained magnitudes being transformed from three-phase abc-system of coordinates into two-phase dq-system of coordinates, and generating reference voltage signals for d- and q-components of total voltage. Extra voltage signals are generated in proportion to d- and q-components of total voltage. Difference voltage signals are generating by subtracting appropriate extra voltage signals from reference voltage signals. Voltage comparison signals are generated by integrating voltage signals and voltage control signals are generated by summing voltage comparison signals with those proportional to voltage difference signals. Reference signals are generated for every source operated in parallel, proportional to appropriate voltage control signals. Extra signals are generated in proportion to d- and q-components of source current, as well as difference signals, comparison signals, signal of control over summation of comparison signals. Also generated are signals proportional to difference signals and signals proportional to d- and q-components of source current. Now modulating signals in abc-coordinate system are generated.

Method to control static stabilised dc voltage sources operating in parallel into common load / 2381608
Invention relates to electrical engineering and can be used in organising electric power generation systems or uninterrupted power supply systems with sources connected in parallel into common load. Proposed method comprises generating voltage setting signal and measuring voltage at common load and output current of every source, generating negative voltage feedback signal and extra voltage signal by integrating negative voltage feedback signal. It includes also generating voltage control signal at common load by summing negative voltage feedback signal and extra voltage signal, generating load current portion setting signal for every source at common load in proportion to common load voltage control signal, proportionality coefficient being equal to source rated current-to-load rated current ratio, generating negative current feedback signal and extra current signal by integrating negative current feedback signal, and generating control signal for every source by summing three components, i.e. extra current signal, negative current feedback signal and that proportional to current of the given source.

Method to control static stabilised ac voltage sources operated in parallel to common load / 2379812
Invention relates to electrical engineering and can be used in constructing electric power generation or uninterrupted power supply systems. Proposed method comprises amplitude comparison signal is shaped by integration of the difference between amplitude reference signal and that of total signal corresponding to difference between current reactive components. Note that aforesaid difference voltages of active and reactive current components are formed as the difference between appropriate current components of only two sources, namely the difference between current components of the given and the other source, or the difference between current components of the other sources. Note here also that every difference in forming appropriate total signals is used only one time.

Plant for parallel operation of converters / 2376695
Plant for parallel operation of converters relates to electric engineering. The plant includes at least two stabilising converters of direct current. The power part output of each stabilising converter is coupled with output buses through disconnecting diodes. In addition, each stabilising converter contains output voltage stabilisation circuit consisting of output voltage sensor. The output voltage sensor output is coupled with one of the inputs of output voltage differential amplifier with its output being connected with control input of pulse width modulator. The latter is linked with control input of stabilising converter power part via amplifying and disconnecting assembly. The output current stabilising circuit containing output current sensor in stabilising converter is coupled with differential amplifier input with its one lead and with the power part of converter with the other lead. Besides output current differential amplifier output is coupled with the first input of comparison device. The second input of comparison device is linked with voltage setting adjustment unit, while its output connects the second input of the output voltage differential amplifier. The output current sensors in stabilizing converters are interconnected by their inputs and coupled with output buses. Besides catching diode is introduced into the plant, which is connected between differential amplifier inputs of output current stabilisation and diodes cathodes are joint.

Device for uniform distribution of reactive power / 2359310
Present invention relates to electrical engineering. The proposed device is provided with voltage source regulators, with the same number of input terminals for each regulator. The device contains the same number of groups of coils of first and second differential inductive current sensors, as well as the same number of parallel operation transformers, as there are input terminals at each regulator. Each of the coils in any group of coils of the first and second differential sensors is inductively coupled with one of those load current conducting wires of the above mentioned voltage sources, which are connected between similar terminals of these sources and one of the common buses, to which is connected the load. The coils of the first and second differential inductive current sensors, inductively coupled with the load current conducting wires of any of the sources, form a set of coils for all groups, and each parallel operation transformer is connected to coils of only one group and has the same number of turns on all windings. Mutual inductance of all coils of the first and second differential inductive current sensors with load current conducting wires has values inversely proportional to nominal current of voltage sources. Terminals of the primary windings of the parallel operation transformers are connected to leads of the coils of the first differential inductive current sensors, related to the driving voltage source, and secondary windings of any parallel operation transformer are connected between input terminals of voltage source regulators and the beginning of those coils of second differential inductive current sensors, which are inductively coupled with current conducting wires of these sources. The ends of these coils are connected to output terminals of these voltage sources, to which are connected the said current conducting wires. Also there are is the same number of extra sets of coils of differential inductive current sensors, as there are parallel connected voltage sources. Each one of them is provided with one set of coils of first differential inductive current sensors and one set of coils of second differential current sensors, as well as a switch, closing contacts of which are connected in parallel to terminals of the primary windings of parallel operation transformers. All input terminals of voltage regulators of all driven and driving sources are connected to corresponding output terminals of sources through the given circuits, containing secondary windings of parallel operation transformers and coils of second differential inductive current sensors.

Device for distribution of reactive load between generators operating in parallel / 2346371
Invention refers to the sphere of electrical engineering and is to be utilised for control over parallel operation of, for example, shipboard generators with quasistatic external characteristic. The invention concept consists in the device being designed as additionally equipped with a shared bus and circuit-opening block contacts of line contactors with the extreme generator selection unit equipped with two resistors, a reference-voltage source, amplifier substractors, decoupling diodes and circuit-opening block contacts (numbering as many as the generators), as well as signal conditioners and isolation diodes (numbering twice as many as the generators). The resistors are connected via the shared bus to the negative outputs of the reactive load sensors with the other resistor ends connected to the cathodes of respectively the first and the second trios of isolation diodes whose anodes are accordingly connected via the signal conditioners to the positive outputs of the reactive load sensors (first trio) and the amplifier substractor outputs (second trio). The amplifier substractor inputs are bridged with the circuit-opening block contacts of line contactors with the inverting input additionally reversely connected via the decoupling diodes to the positive terminals of the load sensors output and the non-inverting inputs connected to each other and to the plus output of the reference-voltage source, the latter's minus output connected to the shared bus and the common points of the amplifier substractors. The signal conditioner outputs are connected to the inputs of the relevant AND gates.

Device for voltage control and loads alignment in parallel operating generators / 2345461
Invention relates to electrical engineering and may be used for automatic control of generators operating in parallel with loads alignment between them. The essence of the invention is that the additional relay element provides control signal correction. In addition the generator output of linearly variable voltage is connected with relay control signal correction input. The outputs and the first and third, second and fourth AND-element are coupled respectively with the inputs of the first and second key elements.

Method for control of static stabilized ac voltage sources operating in parallel to common load / 2256274
Instantaneous values of voltage at a common load and currents of sources are measured, active and reactive components of the powers of the sources are measured, standard voltages of the amplitude and phase of the control signal are formed, additional signals of the amplitude and phase of the control signal are formed, signals of comparison of the amplitude and phase are formed by integration of the difference of the respective standard signals and additional signals, in proportion to the respective signals of comparison the amplitude and the phase of control signal, standard voltages of the amplitude and phase of one of parallel operating sources are formed, responsible for stabilization of the parameters of the common voltage, formed constant and corresponding to the rated values of the voltage parameters, the additional signals of this source are formed respectively in proportion to the amplitude and phase of the common voltage, and for each of the rest parallel-operating sources the standard voltages, amplitudes and phases are formed in proportion respectively to the active and reactive components of the source power responsible for stabilization of the parameters of the common voltage, with a coefficient of proportionality equal to the ratio of the rated full powers of each source and the source stabilizing the voltage parameters, and the additional signals of the amplitude and phase of the rest sources are formed equal-respectively to the active and reactive components of their power.

Reactive power uniform distribution apparatus / 2281543
Apparatus is designed for uniform distribution of reactive power between connected for parallel operation voltage sources having voltage regulators of those voltage sources with the same number of inlet terminals of each voltage regulator. Apparatus includes several groups of windings of differentiating induction measuring transducers (one for each voltage source); number of said groups is equal to number of inlet terminals of each voltage regulator. Each winding of any group is coupled inductively with one of load-current conductors of said power sources that are connected to inlet terminals of voltage regulators of said sources. Load current conductors which are inductively coupled with windings of the same group are connected between similar-polarity terminals of said voltage sources and one of common buses connected with load. Apparatus includes in addition (one for each group of windings) parallel-operation transformers. Each transformer is connected with windings only of one group and it has the same turn number in all windings. Primary windings of said transformers are connected to windings related to first (driving) power source having voltage regulator whose inlet terminals are connected to outlet terminals of said source. Each secondary winding of any transformer is connected between inlet terminal of voltage regulator of other (driven) voltage source and back end terminal of winding inductively coupled with current conductor of said source. Lead end terminal of said winding is connected to such outlet terminal of voltage source that is connected with said current conductor. Voltage sources with different nominal currents are used with windings whose mutual inductance with load electric current conductors have voltages inversely proportional to nominal currents of voltage sources.

FIELD: electricity.

SUBSTANCE: in a control method, based on conversion of instantaneous values of voltage at a common load and output currents of sources from a three-phase abc-system of coordinates into a double-phase dq-system of coordinates, the first and second differential signals are generated by subtraction of accordingly d- and q-components of currents from only two sources, the first and second signals of comparison are generated for d- and q-components of a control signal, stabilising parameters of voltage of direct sequence on the common load and current-distributing loads of direct sequence between sources, in differential signals the final number of harmonic components is identified with maximum amplification ratio, generation of d- and q-components of a control signal is carried out by subtraction of the sum of identified harmonic components accordingly from the first and second differential signals from the first and second signals of comparison, amplitude and phase of modulating signals are generated by reverse conversion of d- and q-components of the control signal from a double-phase dq-system of coordinates into a three-phase abc-system of coordinates.

EFFECT: increased evenness of load current distribution between parallel operating sources due to even distribution of current of reverse sequence of a load between sources.

3 dwg

The invention relates to the electrical engineering and power electronics and may be used for constructing systems of generation of electric energy of alternating current, or uninterruptible power supply systems, in which to achieve qualitative indicators output energy used static converters of electrical energy. The primary sources from unstable parameters of input of energy in such systems can serve as a network of industrial frequency with rectifier, synchronous generator with a variable speed of rotation of the shaft with rectifier or source DC voltage: battery, a fuel cell or solar battery. The function of maintenance of qualitative parameters of the generated electric power is vested in the static Converter and output power low pass filter.

To increase the capacity and reliability of power supply sources are included in parallel to the overall load. This raises the problem of distribution (uniformly for the same rated power or proportional nominal power sources at different power sources) load voltage between parallel sources.

There is a method to control the static stable sources of AC voltage, operating in parallel to the overall load [RF Patent №2381609, H02J 3/46. Way of management of the static stable sources of AC voltage, operating in parallel to the overall load / N. Borodin, S.A. Kharitonov. - Publ. 10.02.2010. - Bul. №4], which is that a measure of the instantaneous voltage values on the total load currents and springs, instantaneous values of the total voltage and current of each source transform of three-phase abc-coordinate systems in a rotating with a constant frequency W, two-phase dq-coordinate system, generate a reference voltage signals for d - and q-components of the overall voltage constant and relevant nominal values of amplitude and phase of General stress, form the first and second additional signals voltage proportional to d - and q-components total voltage, form the first and second differential voltage signals by subtracting the relevant additional voltage signals from the reference voltage signals form the first and second signals comparison voltage integration of first and second differential voltage signals form the first and second control signals voltage summation of the first and second signal comparison voltage signals proportional respectively the first and second differential voltage signals for each of the parallel sources form the first and the second reference signals proportional, respectively, to the first and second control signals voltage with coefficients of proportionality, equal treatment nominal current value of the source to the nominal value of the load current, form the first and second additional signals is proportional, respectively, d and q-components-current source, the first and second differential signals by subtracting the relevant additional signals from the reference signals, the first and second signals comparison by integrating the corresponding differential signals, the first and second control signals by summing the corresponding signals comparison, signals proportional to the first and second differential signals and signals proportional d and q-components of currents sources, form the baseband signals for each source by the conversion of the first and second control signals of the two-phase dq-system of coordinates in a three-phase abc-coordinate system.

This method of control of parallel static sources using converting three-phase voltage and current sources from three-phase abc-coordinate system in two-phase rotating dq-a coordinate system and back, using the operations of integration in the formation of signals comparison effectively ensures stabilization of parameters only direct the sequence of General tension and distribution components only direct sequence currents sources with an unbalanced load. The method does not provide the distribution between sources of zero sequence currents arising from asymmetry of the load.

Indeed, with an unbalanced load current of each phase a, b, c, each k-th source , can be represented as a sum of components of direct and inverse symmetric and zero sequences [Neiman LR Theoretical foundations of electrical engineering: 2 so the Textbook for high schools. Volume 1 / LR Neumann, HP Demircan. - Leningrad: Energoizdat. Leningrad. separa-tion, 1981. - 536 S.]:

where , , - amplitude direct, inverse and zero sequence currents of the k-th source;

V - main harmonic frequency component currents;

Interval is a phase shift zero-sequence.

Convert unbalanced currents of k-source (1) in a rotating with a constant frequency W dq-a coordinate system on the known relationships [Important A.I. Transients machines AC / A.I. the Important. - L: Energiya, Leningrad. separa-tion, 1980. - 256 C.]:

where - d - q-components of currents of the k-th source;

Phi is a phase shift of the rotating coordinate system relative to the vector direct sequence;

, , - instantaneous output phase current sources.

Substituting expression (1) in expression (2), we obtain:

The last expression (3) show that the use of this method of control with an unbalanced load with the formation of d - and q-making currents of k-source, include the parameters of direct and inverse sequence currents. Direct sequence presented in d - and q-making currents of the k-th source of constant signals, and therefore, when you use when forming signals comparison operations of integration will be distributed in proportion to the nominal current of each source. The reverse sequence of the load current is presented in d - and q-making currents of the k-th root of the second harmonic component, and therefore will be shared between concurrent sources arbitrarily.

In addition, there is a method to control the static stable sources of AC voltage, operating in parallel to the overall load [RF Patent №2380820, NM 5/297, NM 7/493, NR 13/00. Way of management of the static stable sources of AC voltage, operating in parallel to the overall load / N. Borodin, S.A. Kharitonov. - Publ. 27.01.2010. - Bul. №3], which is the prototype of the invention consists in that for each source measure instantaneous values of output voltage and current instantaneous value total voltage and output current of each source transform of three-phase abc-coordinate systems in a rotating with a constant two-phase frequency W dq-coordinate system, constitute a reference signals for d - and q-components output voltage source, form the signals is proportional to d - and q-component of the output voltage, form the signals is proportional to d - and q-component of current sources, each source form of the first differential signal by subtracting d-components of current sources and second the differential signal by subtracting q-components of current sources, and above first and second differential signals form, respectively, as the difference d - or q-making currents only two sources, namely the difference between making currents of this and other sources, or difference other components of current sources, and each difference in the formation of the corresponding differential signals is used only once, the first differential signal summarize with the signal that is proportional to d-component of the output voltage, the second differential signal summarize with the signal, proportional q-component of the output voltage, form the first signal comparison by integrating the differential reference signal for the d-component of the voltage source to the total signal corresponding to the difference d-components of current sources, and the second signal comparison by integrating the difference between the reference signal q-component of the voltage source to the total signal corresponding to the difference q-components of current sources, form d - a or q-components of the control signal, form the amplitude and phase modulation reverse conversion of d - and q-the components of the control signal of the two-phase dq-system of coordinates in a three-phase abc-coordinate system.

This method also uses the conversion currents source of three-phase abc-coordinate systems in a rotating dq-coordinate system. So it is also fair above ratios (1)...(3), and in the exercise of this control method with an unbalanced load effectively will be distributed components of the load current direct sequence between sources. The reverse sequence of the load current is distributed randomly, and the uneven distribution of load current between the sources is low.

In addition, the use of static converters that use, as a rule, pulse-width modulation sources, leads to the appearance in spectra generated voltage and current sources of a wide range of Raman harmonic components:

where V - main harmonic frequency component of the modulating signal;

V - switching frequency pulse-width modulation;

p=1, 2, ...;

n=0, 1, ....

Some of these harmonics is converted in the reverse sequence, and they will be distributed between the sources are unevenly. Thus, the current distribution of the load between running in parallel sources with an unbalanced load is low due to uncontrolled and arbitrary distribution of the reverse current of the load between running in parallel sources.

The task of the invention consists in increasing the uniform distribution of the load current between parallel sources due to an even distribution of current reverse sequence load between sources.

This is achieved by the known method of management of the static stable sources of AC voltage, operating in parallel to the overall load when its asymmetry, for each source, measure instantaneous values of output voltage and current, instant total voltage and output current of each source transform of three-phase abc-coordinate systems in a rotating with a constant two-phase frequency W dq-coordinate system, constitute a reference signals for d - and q-components of the output voltage source, generate signals proportional d and q-component of the output voltage, form the signals is proportional to d - and q-component of current sources, each source form of the first differential signal by subtracting d-components of current sources and second differential signal by subtracting q-components currents sources, and above first and second differential signals form, respectively, as the difference d - or q-making currents only two sources, namely the difference between making currents of this and other sources, or the difference between the components of current other sources, and each the difference in the formation of the corresponding differential signals is used only once, the first differential signal summarize with the signal that is proportional to d-component of the output voltage, the second differential signal summarize with the signal that is proportional to q-component of the output voltage, form the first signal comparison by integrating the differential reference signal for the d-component of the voltage source to the total signal corresponding to the difference d-components of current sources, and the second signal comparison by integrating the difference between the reference signal q-component voltage source and the total signal corresponding to the difference between the q-components of current sources, form d and q-components of the control signal, form the amplitude and phase modulation reverse conversion of d - and q-components of the control signal of the two-phase dq-system coordinates in a three-phase abc-coordinate system, in the first and second differential signals allocate finite number of harmonic components with a maximum gain of, and the formation of d - and q-components of the control signal produced by subtracting from the first and second signals compare the amounts allocated harmonic components respectively from the first and second differential signals.

Figure 1 shows one possible flowchart that implements the proposed control method. Figure 2 shows the graphs of the results of modeling of the prototype method in parallel work of three converters. Figure 3 shows the graphs of the results of modeling of the proposed method in parallel work of three converters.

The block diagram in figure 1 includes N parallel three-phase sources EAST 1 , EAST 2 , ..., EAST N (1, 2, 3) for the total load N (4). Each source includes the source of the reference signal d-component of the output voltage (5) and the source of the reference signal q-component of the output voltage (6), which are connected with the first, umenshenie inputs schemes subtraction (7 and 8). Second, the deductible input circuits subtraction (7 and 8) are connected to the outputs proportional links for d - and q-components of the output voltage and (9, 10). Third, the deductible input circuits subtraction (7, 8) are connected to the outputs proportional links differences d and q-components of current sources and (11, 12). Outputs schemes subtraction (7, 8) connected to inputs integrators and (13, 14). Outputs integrators connected with umenshenie inputs schemes subtraction (15, 16). Deductible input circuits subtraction (15, 16) are connected to the outputs of adders (17, 18). Outputs schemes subtraction (15, 16) connected to inputs reverse converters coordinate PC -1 (19), the outputs are connected to inputs systems impulse-phase control SIFU i (20). Outputs systems impulse-phase control is connected with the power schemes static frequency converters PCH (21). Power circuit transducers are connected to the outputs of sources unstable voltage Uc i (22). Outputs of power schemes through a low-pass filters f i (23), gauges of the instantaneous phase current DTA, DTV, TPA (24 26...) are connected with a total load of N (4) and direct inputs converters coordinate output voltage PC (27). The direct outputs of the converters coordinate output voltage PC (27) connected to inputs proportional links and (9, 10). The outputs of the sensors momentary values of phase currents DTA, DTV, TPA (24 26...) connected to inputs direct converters coordinate output currents PC (28), the outputs are connected to inputs schemes subtraction (blocks 29...34). Outputs schemes subtraction (29...34) connected to inputs corresponding proportional links and (11, 12) and inputs allocation patterns of harmonic components Wp 1 Wp ...p (35...38). Outputs allocation patterns of harmonic components Wp 1 Wp ...p (35...38) connected to the inputs of the relevant adders (17, 18).

Load N (4) can be a resistor or a serial or parallel resistor and throttle. Sources of reference signals for the d-component of the output voltage (5) for q-component of the output voltage (6), for example parametric stabilizer (see Sources of power electronic equipment: the manual / Under the editorship of G.S. Neivelt. - M: Radio and communication, 1986). Schema subtraction (units 7, 8, 15, 16 and 29, ..., 34)proportional units (blocks 9, ..., 12), integrators (13, 14) and adders (17, 18) are typical elementary units, known from theory of automatic control (see theory of automatic control. B1. Theory of linear systems of automatic control. Edited by A. A. Voronov. Textbook. the manual for high schools. - M: The High. school, 1977). Inverter coordinate PC -1 (19) implements known of electromechanics and theory of automated electric drive conversion of two dq-coordinate system of coordinates rotating with a constant frequency W, three-phase, with a constant frequency W abc-coordinate system (Important A.I. Transient processes in the machines of alternating current. - Leningrad: Energiya, Leningrad. separa-tion, 1980), and is a multiplier analog signals (Timokiev V.N., Velichko L.M., V.A. Tkachenko Analog multiplier products signals in electronic equipment. - M: Radio and communication, - 1982. - 112 S.). SETH i (20) - standard system impulse-phase control, which implements the principle of vertical management (see V.S. Rudenko, V. Senko, IM Chizhenko. Basics converters. - M: The High. school, 1980). Power circuit static source AC voltage of the inverter (21) can be a direct frequency Converter or serial connection of the rectifier and inverter or inverter (see V.S. Rudenko, V. Senko, IM Chizhenko. Basics converters. - M: The high. school, 1980). Source unstable voltage Uc (22) - industrial network or synchronous generator with variable rotational speed of the rotor or a rechargeable battery. Power filter f (23), for example, the single LC filter in each output phase or With filter on each output phase. Sensors instantaneous phase current (24...26), for example, current transformers. Direct converters coordinate PC (27, 28) implement known of electromechanics and theory of automated electric drive transformation of three-phase values (currents and voltages) of three-phase abc-coordinate system in a rotating with a constant frequency W, d and q-components of the system dq-coordinate (Important A.I. Transient processes in the machines of alternating current. - Leningrad: Energiya, Leningrad. separa-tion, 1980) and are multipliers of analog signals (Timokiev V.N., Velichko L.M., V.A. Tkachenko Analog multiplier products signals in electronic equipment. - M: Radio and communication. - 1982. - 112 S.). Scheme of allocation of harmonic components Wp 1 Wp ...p (35...38) can be a high-profile parts, for example,

or ,

implemented in analog form (see Theory of automatic control. Part 1. Theory of linear systems of automatic control. Edited by A. A. Voronov. Textbook. the manual for high schools. - M: The High. school, 1977), and to prevent the temperature dependence of the parameters of the links in the digital form (see Sergienko A.B. Digital processing of signalov. - SPb.: Peter. -2006. - 751 S.).

The proposed method is as follows. Formed (units 5 and 6) reference signals for the d-component and q-component of the output voltage (5, 6), which is a constant voltage, coming at first, umenshenie inputs relevant schemes subtraction (7, 8). Converters coordinate PC (27, 28) convert three-phase system measured sine values, respectively output voltages and currents (24 26...) sources in rotating with a constant frequency W a system of two d - and q-coordinates, respectively, of voltages or currents ( , ), which represents the sum of DC voltage signal and harmonic components. D and q-components of the output voltage is transmitted through proportional links (9, 10) on the second, umenshenie inputs schemes subtraction (7, 8). D and q-components of currents sources come to the inputs schemes subtracting their sources with a positive sign and the inputs schemes subtracting other sources with a negative sign (29...34). Schema subtraction (29...34) form the difference between d-making currents and the difference between the q-making currents Differential signals through proportional links (11, 12) come on third, umenshenie inputs schemes subtraction (7, 8) and the inputs allocation patterns of harmonic components Wp 1 Wp ...p (35...38). Schema subtraction (7, 8) form the difference corresponding to the reference signal and the corresponding total signals. These tensions come on integrators (13, 14)that form the first (13) and the second (14) signals comparison by integrating the difference between the respective reference and total signals. Scheme of allocation of harmonic components Wp 1 Wp ...p (35...38) allocate from the corresponding differential signals a finite number of harmonic components depending on those frequencies, which are configured schemes, and on the outputs of adders (17, 18) is the sum of the signals allocated harmonic components. Output voltage integrators come on umenshenie inputs schemes subtraction (15, 16). Deductible inputs schemes subtraction (15, 16) receives signals allocated harmonic components. Output signals schemes subtraction (15, 16) come on inverter coordinate PC -1 (19), which establishes a three-phase system modulating stress, the amplitude and the phase of which is determined by the input signals PC -1 (19), that is, the results of the summation. In the system of phase-impulse regulation (20) modulating voltage is converted into a sequence of modulated pulses that provides switching of power switches schemes static source AC voltage of the inverter (21)that converts the energy source unstable voltage Uc i (section 22) AC voltage stable frequency Ω to the parameters controlling voltage SIFU i (20). Power filter f (23) largely exclude high-frequency components of the spectrum of the output voltage and current sources, ensuring their sinusoidally.

Increasing the uniform distribution of the load current between parallel sources is due to the fact that there is an allocation in the differential signals harmonic components that define the reverse currents of sources, with maximum gain. Therefore, these components due to the negative feedback is the same.

Let us prove that the proposed control method will be aligned currents reverse sequence sources. To do this get the difference images by Laplace d and q-making currents k-th and k+1 sources in closed systems of regulation the sources taking into account these transactions and analyze the ratio of the harmonic components in d - and q-making currents of the k-th and k+1 sources that according to expressions (1) are determined by the inverse sequence currents sources.

According to the block diagram in figure 1 image for the Laplace d and q-components of the control signal of the k-th source arriving at the inputs reverse Converter coordinate PC -1 (19)can be represented in the form:

where are pictures of reference signals output voltage to th source;

, - coefficients proportionality, matching the levels of each of the reference signal and d and q-components of the output voltage of the k-th source;

, images of d - and q-stress components on the overall workload;

- the coefficients of proportionality, which determine the depth of the regulation on the difference between d - and q-components of current k-th and k+1 sources;

, , , image d and q-making currents of the k-th and k+1 sources;

- transfer function integrators d and q-components that form the signals of comparison;

W pi (s) is the transfer function of the schemes of allocating the i-th harmonic component in the differential signals;

p - the amount of harmonic components in the differential signals.

Inverter coordinate PC -1 (19) performs conversion of two-phase dq-system of coordinates in a three-phase abc-coordinate system on the known relationships [Important A.I. Transient processes in the machines of alternating current. - L: Energiya, Leningrad. separa-tion, 1980]:

where , , is instantaneous phase modulation of signals in abc-coordinate system k-source;

L -1 {...} - operation inverse Laplace transform;

where , is the sum of all other elements included in the expressions (14) and (15)containing variables and transfer functions with shifted by + jΩ and ±j2Ω complex variable S and d and q-components of voltage on the overall workload and appropriate reference signal;

;

Express the difference between d - and q-components of current sources with parallel operation of two sources (N=2) expression (16) for k=1, 2:

Analysis of expressions (17) and (18) shows that in the numerator of these expressions is the sum of the transfer functions of allocation patterns of harmonic components W pi (s) included in the first degree, and the denominator in the second. Scroll in expressions (17) and (18) transfer functions for the i-th harmonic component ω i , in the form of:

Here is the expression (19) to a common denominator and define the difference harmonics ω i in d - and q-components of current sources. To do this, we will substitute the expressions (17) and (18) s=j·ω and i consider that the values of all the others, except corresponding to the expression (19), the transfer functions modulation i will take the final value. The amount on the frequency s=j·ω i will be zero. Therefore, the expression (17) and (18) when s=j·ω i converted to the form:

The last expression (20) shows that the selected harmonic components from the differences in d - and q-components of current sources with the proposed control method will be equal. Consequently, reverse currents of sources, which determine these harmonics, will also be equal.

With a larger number of parallel sources (N>2) expressions for the difference d and q-components of current sources will be more complicated than expressions (17) and (18). But the maximum number of works for the transfer functions of allocation patterns of harmonic components of the numerator will be in these ratios less per unit of the relevant maximum number of works for the transfer functions of allocation patterns of harmonic components of the denominator. The result will be performed ratio:

Figure 2 presents plots of stress on the total load currents and sources obtained from simulation package PSim parallel operation of three sources for the total load for the prototype method. Static converters - inverter PWM. Output frequency 400 Hz, the frequency of 20 kHz, nominal current voltage is 115 V, load resistance: phase A - 1,65 Ohm, phase b and C - idle (1 MW).

Figure 2 presents: instantaneous phase voltage on the total load ulo(A), u(B), UN(C) (first schedule), instantaneous values of currents loaded phase And three sources I 1 (A), I 2 (A), I, 3 (A) (second schedule), effective values of phase currents And sources I 1eff (A), I 2eff (A), I 3eff (A) (third schedule), instantaneous values of d - and q-making currents the first source d(1), q(1) (fourth schedule), second d(2), q(2) (fifth schedule) and third d(3), q(3) (sixth schedule) sources. Figure 3 presents similar graphs of these variables in the implementation of the proposed control method, selecting the second harmonic component (800 Hz) differences in d - and q-making currents in each source. The simulation results show that with the implementation of the proposed control method is the alignment of the instantaneous values of current sources (the second graphics) and current values of current sources (third graphics).

Thus, the proposed method increases the uniform distribution of the load current between parallel sources due to an even distribution of current reverse sequence load between sources.

Way of management of the static stable sources of AC voltage, operating in parallel to the overall load when it is unbalance, which is that for each source measure the instantaneous values of output voltage and current instantaneous value total voltage and output current of each source transform of three-phase abc-coordinate systems in a rotating with a constant two-phase frequency W dq-coordinate system, constitute a reference signals for d - and q-components of the output voltage of the source form of the signals is proportional to d - and q-components of the output voltage, form the signals is proportional to d - and q-component of current sources, each source form of the first differential signal by subtracting d-components of current sources, and second differential signal by subtracting q-components of current sources, with these first and second differential signals form respectively as the difference d - a or q-making currents only two sources, namely, the difference between making currents of this and other sources, or the difference between the components of current other sources, and each difference in the formation the corresponding differential signals is used only once, the first differential signal summarize with the signal that is proportional to d-component of the output voltage, the second differential signal summarize with the signal that is proportional to q-component of the output voltage, form the first signal comparison by integrating the differential reference signal for the d-component of the voltage source to the total signal corresponding to the difference d-components of current sources, and the second signal comparison by integrating the difference between the reference signal q-component of the voltage source and total signal corresponding to the difference q-components of current sources, form d and q-components of the control signal, form the amplitude and phase modulation reverse conversion of d - and q-components of the control signal of the two-phase dq-system of coordinates in a three-phase abcthe coordinate system, characterized in that in the first and second differential signals allocate finite number of harmonic components with a maximum gain of, and the formation of d - and q-components of the control signal produced by subtracting from the first and second signals comparison the amount allocated harmonic components respectively from the first and second differential signals.