Active Transformer Power Conditioner (Machine-translation by Google Translate, not legally binding)

专利摘要:
Active Transformer Power Conditioner. This patent presents a new transformer structure, the Active Power Conditioning Transformer, characterized by a magnetic circuit design and auxiliary windings that allow the integration of series and branch compensation circuits in the structure of the transformer. The voltages and currents in the auxiliary windings are regulated by the use of electronic power converters or by other passive circuits. Its operating principle is based on the regulation of the magneto motive force and the flows of the transformer, which are directly related to the electrical magnitudes of the primary and secondary windings of the transformer, thus regulating the voltage and current in these windings. The resulting transformer provides serial and parallel compensation services to the network and to the load in a single integrated transformer, which has advantages in terms of its construction, size, flexibility and cost. (Machine-translation by Google Translate, not legally binding)
公开号:ES2684108A1
申请号:ES201730484
申请日:2017-03-30
公开日:2018-10-01
发明作者:Mohamed ATEF ABBAS EL SAHARTY；Pedro RODRIGUEZ CORTÉS；José Ignacio CANDELA GARCÍA
申请人:Universitat Politecnica de Catalunya UPC；
IPC主号:

专利说明:

Active Transformer Power Conditioner
SECTOR OF THE TECHNIQUE
This invention concerns a new Active Power Conditioner Transformer (TAAP), characterized in that, in addition to having the primary and secondary windings of a conventional transformer, it also has auxiliary windings and a magnetic circuit with additional magnetic paths that allow controlling at will the magnetic flux in its secondary winding, regardless of the magnetic flux in the primary winding, and the Magneto-Motor Force (FMM) in the primary winding, regardless of the FMM in the secondary winding. Therefore, whenever working with alternating voltages and currents that make possible the existence of magnetic induction,
BACKGROUND OF THE INVENTION
The expansion of power systems poses several challenges. These include the increase in the peak value in the demand for electric power by consumers, the use of non-linear loads that absorb distorted currents and a growing saturation of power lines. All this affects the power quality, stability and reliability of the power system, as well as the price of energy [1] - [2]. The trend in the evolution of power systems makes the methods traditionally used to mitigate the problems described above ineffective, especially when there are continuous variations in the generation and demand of the network [3]. The power grid of the future is expected to be intelligent, efficient, fault tolerant and self-repairable. Thanks to the advances in the application of power electronics to power systems, it is possible to control its dynamics at high power levels, which allows to solve the challenges previously posed [4].
Current power systems use modern solutions, such as Flexible Alternating Current Transmission Systems (FACTS-Flexible AC Transmission Systems) and Power Conditioning Devices (CPD -Custom Power Devices) to improve their behavior. These devices have been shown to improve the performance and profitability of transmission and distribution facilities in the operation of the power system [5] - [6]. In general, currently available power compensation devices incorporate power converters designed to offer series, parallel, series-parallel compensation or a combination of them. However, these devices differ from one to another in the configuration of their power electronics and the type of service provided to the power system. The series-parallel system known as the Unified Power Flow Controller (UPFC) for transmission systems and the Unified Power Quality Controller (UPQC) for distribution systems combine the advantages of the series and bypass compensation in a single unit [7] - [8]. These devices allow real-time control of the variables on which the behavior of the power systems depends, such as the voltage and current waveform, their amplitude and their phase angle [9].
The connection of the UPFC and the UPQC to the power system can be achieved through a transformer [10] or without a transformer [11]. The limitations in the applicability of the transformer-based compensation system are mainly due to the use of complicated and bulky zig-zag transformers to achieve the desired voltage, current and waveform [11]. On the other hand, the non-isolated connection of these systems on the high voltage side of the electrical system requires complex converter structures, which increase the size and cost of the installation, while the installation on the low voltage side requires large compensation currents, increasing the size, cost and heat dissipation [12]. The transformer is an essential element in a compensation system, since it adapts to the voltage levels between the inverter and the power grid, while isolating both systems and provides flexibility to use voltage source converters (VSC-Voltage Source With pour) standard.
Transformers are an essential part of the electrical energy transfer system. Their presence at the transmission and distribution levels of the network, raises the possibility of combining them with compensation systems that require an isolated connection [13]. Under that perspective, the transformers of a power system would continue to participate in the energy transfer task, while providing services to the power system at its connection point. Such an integrated approach would lead to greater controllability of power system behavior in terms of stability, reliability, continuity of supply and power quality. Such behavior can be achieved by integrating auxiliary magnetic circuits in the transformer, which allows controlling the coupling between both sides of the transformer. This new transformer configuration reduces the number of magnetic components of the system, while providing the required compensation services, which ultimately reduces the cost and volume of the system to be built, while providing compensation services at its point. of network connection.
The integration of magnetic devices and power converters into high power applications has been presented in the form of coupled inductors, coupled inductors and transformers, or integrated transformers (several transformers sharing a common core) [13]. Modifications in the magnetic structure of the transformer to integrate bypass compensation [14] and series compensation [15] based on electronic power converters have been shown to give rise to the expected advantages. These configurations have been used in FACTS and CPD applications for series voltage compensation [16] - [17] and bypass reactive power compensation [14], passive series harmonic filtering [18], control of serial power flow by controlled saturation of the transformer [19}, the use of multiple shunt converters sharing a common transformer core [20], the variable inductor [21] and other applications that use series or shunt compensation. Although the modeling principle of the complex magnetic structure integrated in these transformers has been presented in the literature [13], current devices explore the multi-series or multi-parallel compensation of the power system.
Several solutions reported in the literature suggest modifying the structure of the transformer core to incorporate the control of the magnetic bypass flow with the help of a power control source [22], which internally forms an effect equivalent to the series electrical compensation. Such approaches control the permeability of the core material by producing a transverse flow through the core sections, thereby controlling the flow between the different windings of the core and thereby controlling the amplitude of the induced voltages. Such modifications include the introduction of shunt cores [23], shunt coils embedded in the core [24] - [25] and the orthogonal core structure [26] - [27]. However, such core structures were intended to be applied in voltage regulation and in the creation of variable inductances. In addition, these approaches involve using specially designed core structures, which may include air gaps and special winding configurations that complicate the construction of such devices.
The closest approach to TAAP presented in this patent is a UPFC application based on the use of the Sen transformer [28], which integrates an electronic power converter and a cost-optimized transformer. By using tap changers to inject a compensation voltage with controllable parameters, the Sen transformer can function as an UPFC with certain degrees of freedom [29]. However, the Sen transformer has several limitations due to the use of tap changers.
5 which entails certain deficiencies regarding the benefits of a standard UPFC. This makes it incapable of providing certain additional services to the network, such as inertia emulation. In addition, the control of the power flow is performed by jumps using the tap-changer, so it is not possible to carry out a continuous and rapid control over the power flow [30].
In spite of the solutions documented in the literature, the concept of a device with integrated serial-parallel compensation, or with a combination of serial and branch connections in a power transformer, which can provide power compensation services in a way flexible and applicable to both the transmission and distribution networks, it has not yet been reported in the current state of the
15 technique. In fact, this is the design approach of the Active Power Conditioner Transformer (TAAP) object of this patent, which allows to design a transformer that works efficiently in its work of adapting the voltage and current levels of its primary and secondary windings , which also offers voltage and current support services to the power grid to improve its operation.
References
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the EXPLANATION OF THE INVENTION
The Active Power Conditioner Transformer (TAAP) consists of a transformer
electromagnetic that, in addition to the usual primary {2} and secondary {4} windings of
any transformer, incorporates auxiliary windings {6} {8}, wrapped in branches
concrete its magnetic circuit {3}. Provided that the electromagnetic induction effect is
fifteen possible, that is, whenever working with alternating magnetic fluxes in the nucleus
Ferromagnetic transformer {3}, one or more auxiliary windings {6} will be responsible for
regulate the FMM developed by the primary windings of the transformer {2}, with
independence of the FMM developed by secondary windings {4}. By means of the
application of the existing scalar relationship between the FMM developed by a coil and the
twenty current flowing through it, it is mathematically justified that this set of
auxiliary windings {6} allows to regulate the current in the primary windings of the
transformer {2}, regardless of the current flowing through the secondary windings
of the transformer {4}. Likewise, under the same condition of induction existence, one or
several auxiliary windings {8} (other than those mentioned above) will be responsible for
25 regulate the magnetic flux concatenated by the secondary windings of the transformer {4},
regardless of the magnetic flux concatenated by the primary windings of the
transformer {2}. Based on Faraday's law of induction, which establishes the relationship between
the magnetic flux and the induced voltage in a coil, it is mathematically justified that this
set of auxiliary windings {8} allows to regulate the tension in the secondary windings
30 of the transformer {4}, regardless of the voltage in the primary windings
of the transformer {2}. The current and voltage in the auxiliary windings are controlled by
electronic power converters {7} {9}, on which the programming algorithms are programmed
necessary control {12} {13} depending on the services provided by the transformer to the primary electrical circuits {1} and secondary {5} to which it is connected. This flexibility to regulate the voltage in the secondary windings {4} and the current in the primary windings {2} makes it possible that there could be operating points of the transformer where there is no power balance between the primary electric circuit {1} and the secondary electrical circuit {5}. In this case, in order for the transformer to continue working in a stable manner, complying with the principle of energy conservation, it is necessary that the power converters {7} {9} that control the auxiliary windings {6 9
} {8} provide or absorb the power imbalance between the primary {1} and secondary {5} electrical circuits. To do this, the power converters {7} {9} are connected by a link circuit {10} which is responsible for energy balance the transformer by supplying or absorbing power. In the event that there is a balance of power, at least on average, between the primary {1} and secondary {5} electrical circuits, the link circuit {10} will not have to provide net energy and may consist of reactive elements.
According to the above, by conditioning magnetic variables in the transformer core, which requires a special design, it is possible to regulate at will the voltage of the secondary side and the current of the primary side of the transformer. As a result, when the Active Power Conditioner Transformer (TMP) is connected to electrical networks, in addition to performing the conventional function of voltage and current adaptation, it can, by programming the appropriate control algorithms, eliminate harmonics and imbalances of current in the primary circuit, eliminate harmonics and voltage imbalances in the secondary circuit of the transformer, regulate the power flow through it by offsetting the fundamental voltage component of the primary and secondary circuits, regulate the voltage in the primary circuit connection point by injecting the fundamental frequency reactive current into the primary circuit of the transformer, pre-magnetizing the transformer to avoid currents in its connection, conditioning the primary circuit current when working at low levels of charge due to the magnetizing current, d To support the mains voltage on the primary side during short circuits by injecting instantaneous reactive current on the primary side of the transformer, restore the secondary circuit voltage during transient voltage events in the primary circuit by restoring the flow magnetic on the secondary side, attenuate transient oscillations in the power flow through the transformer by regulating the power exchanged by the auxiliary windings, supply synthetic inertia in the transformer connection circuits by regulating the power exchanged by the windings auxiliary and power isolated electrical systems connected on the secondary side of the transformer (with the primary side of the transformer in open circuit) by means of the energy input from the link circuit of the transformer power converters. The main novelty of the Active Power Conditioner Transformer (TAAP) object of this invention is that all these functionalities are achieved by regulating magnetic variables in the magnetic core of a monolithic system that connects to the electricity grid through its primary and secondary windings .
The concept that supports the invention is based on the theory that governs the behavior of magnetic circuits, in which the windings wound in the same magnetic busbar share the same magnetic flux and therefore the FMM developed by said busbar is equal to the algebraic sum of the FMMs developed by each of the windings, so they are equivalent to electrical circuits connected in parallel, in which the total current is equal to the algebraic sum of the currents of each of the circuits. In the same way, the windings wound on parallel-mounted magnetic busbars develop the same FMM, so the magnetic flux concatenated by one of the windings is equal to the algebraic sum of the magnetic fluxes concatenated by the other windings, so they are equivalent to electrical circuits connected in series in a loop, in which the voltage in any of the circuits is equal to the algebraic sum of the voltage in the others. Fig. 2 shows the general structure of the compensation windings of a multi-phase conditioning transformer and multiple series and parallel compensations. With p phases in the transformer, each row {14} represents a single phase consisting of multiple branch magnetic branches {15}. Each branch of each phase represents an equivalent electrical circuit connected in series with the other branches in the same phase. In this description it is considered that the initial end of the transformer is connected to the first branch {16} in each phase, while the final end of the transformer is connected to the last branch {18}. Then, the number of branches m in each phase {17} would represent multiple equivalent series electrical circuits between {16} and {18}. While each branch {16}, {17} Y {18} consists of multiple windings, n, that form an equivalent electrical branch circuit with each of those windings of particular branches. If a series compensation is required, it should be noted that the primary and secondary windings cannot exist in the same branch. Therefore, to incorporate compensation in series, the minimum number of branches is
of three, with primary and secondary windings in independent branches. It is considered that the
Bypass compensation may exist in any branch to compensate for other windings in that branch.
Considering the analogy in which the FMM of each coil can be represented as a
The current source in an electrical circuit and the flows flowing through the magnetic core are represented by the voltage induced in each coil, Fig. 3 shows how each phase consists of several branch circuits and several series circuits. In case of imbalance between different phases, the equivalent flow would flow through the homopolar sequence flow path {19}, as occurs in a multi-phase transformer in an imbalance situation.
10 The Npnk notation is used to represent any winding in the described configuration, while these windings can take any form in the winding architecture. Assuming that the transformer is connected to a balanced and lossless system, the equivalent electrical circuit shown in Fig. 3 illustrates that the FMM induced by F on a branch is equal to the sum of all the FMM induced by each winding in that branch, such and
15 as presented in (1), provided that the total flow of all branches in one phase will add zero (2). This shows the possibility of adjusting the induced voltage in any branch by adjusting the flow of the adjacent branch through one of its windings. Meanwhile, the FMM in all branches are the same, as shown in (3). Therefore, the current in a winding of a branch can be adjusted by varying the FMM developed by the other windings
20 on that branch.
.. :: k
(one )
Fpn = LFp ~
x: l
(2)
; r: n; r: n; r: n
.z .: Fpi ~ .z .: Fpi ~. ~ .z .: Fp; "(3)
.. :: 1 .. :: 1 .. :: 1
The structure in Fig. 2 can be used as a transformer, with the beginning in one branch and the end in another, while the extra existing windings are considered as auxiliary windings that provide conditioning services to the initial and final branches. Based on what is indicated in (1) to (3), the control of the flow and the FMM in the magnetic circuit is achieved through the control of voltage and current in the auxiliary windings of the transformer. This can be achieved through a power converter based on power electronics, as shown in Fig. 4. The power converter {20} can use the transformer windings to transfer energy between them through an energy buffer {21} or directly supply / absorb energy to / from the different windings using an energy source / storage system {22}.
The main features of this combined construction compared to the conventional multi-transformer approach, in which the series and parallel compensators are connected to the network through the use of separate isolation transformers, can be summarized as:
(to) Reduction of the total number of windings and core size compared to the case of having each converter connected through independent isolation transformers.
(b) Magnetic coupling of the circuits of the converters in series and in derivation to the primary and secondary windings of a transformer.
(C) Use of a single transformer with controlled flow with reduced starting currents thanks to the pre-energization of the transformer core.
(d) Elimination of the need to use high voltage / current windings, which are normally present on the primary side of the series and bypass isolation transformers.
(and) Reduction of the total number of windings by 33% compared to the use of several separate transformers.
(F) Reduction of iron requirements by 13% in a multi-phase system. The resulting structure of the armored transformer combines the core of several transformers, one on top of the other, eliminating the need for extra horizontal branches.
The overall cost reduction and the integration of the power converter with the transformer as a single unit make the present invention an attractive approach to minimize the need for several cascade compensation systems.
Brief description of the figures
The features associated with the invention presented in this patent are supported by the following figures:
Figure 1; Shows the general structure of the Active Transformer implementation
Power Conditioner (TAAP).
The following marks are represented in this figure:
{1} Primary electrical circuit
{2} Primary windings
{3} Transformer magnetic circuit
{4} Secondary windings
{5} Secondary electrical circuit
{6} Auxiliary windings for parallel compensation of the primary side
{7} Controllers connected to auxiliary windings in parallel {6}
{B} Auxiliary windings for series compensation of secondary side
{9} Controllers connected to the auxiliary windings in series {B}
{10} Link circuit for power exchange serial and parallel controllers
{11} Control signals of the series and parallel compensation controllers
{12} Control algorithms for managing the quality of supply on the primary and secondary sides
{13} Control algorithms to provide network support services on the primary and secondary side
Figure 2; Front view of the transformer in this invention, with N coils for each p phases, with k series circuits and n branch circuits. The coils are arranged in branches forming n branch circuits, while the branches are joined together with
the yokes forming k series circuits. The yokes come together to close all the phasestogether in one unit.The following marks are represented in this figure:
{14} branches per phase consisting of n coils of the branch circuit
{15} branches per phase connected through the yoke consisting of n bypass circuit coils
{16} primary branches per phase, consisting of n shunt coils per circuit
{17} series branches per phase, consisting of n branch coils per circuit
{18} secondary branches per phase, consisting of n shunt coils per circuit Figure 3; Electrical equivalent circuit of the transformer of Fig. 2 with a homopolar sequence path Lo {19}
Figure 4; Electronic power converter connected to the auxiliary windings of the transformer The following marks are represented in this figure:
{20} Power converter (inverter)
{21} Energy storage
{22} Energy source / storage Figure 5; The Active Power Conditioner Transformer (TAAP) at the single-phase distribution level, consisting of a primary, secondary, series and parallel winding. The series and bypass windings are connected to a three-phase inverter through phase a and b with controlled output voltage v1 / and current i 1 / respectively while a common neutral between both windings is connected to phase c. The secondary winding is connected to a non-linear load that absorbs harmonic currents with secondary voltage v1 /, while the primary coil is connected to a harmonic voltage source V1 11 • The inverter is equipped with a
DC Cdc capacitor whose Vdc voltage is controlled. The control signals in Fig. 7 and Fig. 8 are used to switch the inverter with the gate signals G_8, G _b Y
G_c.
The following marks are represented in this figure:
{23} Single phase TAAP
{24} Primary winding
{25} Winding offset deviation
{26} Series compensation winding
{27} Secondary winding
{28} Non-linear load consisting of a rectifier, LC circuit and resistive load
{29} DC-AC inverter
{3D} DC capacitor
Figure 6; Simplified equivalent electrical circuit of Fig. 5 showing the primary voltage v1 /, branch circuit current i1 /, series circuit voltage v1 /, secondary load current i1 31 and secondary voltage v1 /.
Figure 7; Serial voltage regulator consisting of a PI controller, proportional and resonant controllers. The number of resonant controllers x represents the number of harmonic orders to be compensated. The signals necessary for the operation of controllers are the magnitude of the secondary voltage V1 /, the reference magnitude of the secondary voltage V1 / ', the harmonic voltage reference of the secondary voltage V1 3 1_ h', the instantaneous secondary voltage V1 3 1 , the secondary synchronization signal sin (wth11 and the primary frequency w. The output signal is the serial voltage of the output V1 21 •
The following marks are represented in this figure:
{31} Secondary voltage magnitude controller
{32} Secondary voltage harmonic controller
Figure 8; Shunt current controller consisting of a PI controller, proportional and resonant controllers. The number of resonant controllers x represents the number of harmonic orders to be compensated. The necessary signals for the operation of controllers are DC Vdc bus voltage. the voltage reference DC V dC ·, the primary current i1 /, the primary harmonics reference current i1 r'_h ', bypass current i1 /, the primary voltage synchronization signal of the coil without (wt) 1/1 and primary frequency w. The output signal is the output bypass voltage v1 t
The following marks are represented in this figure:
{33} DC bus voltage controller
{34} Primary reactive power regulator
{35} Bypass Current Controller
5 {36} Primary Harmonic Current Controller
Detailed description of the preferred embodiment
Next, a preferred embodiment of the Active Power Conditioner Transformer (TAAP) according to the present invention will be described with reference to the illustrated figures.
In this embodiment, a single-phase distribution system consisting of a mains voltage with harmonics and a non-linear load that absorbs a harmonic current is considered. The objective of this embodiment is to show the development of an UPQC system to compensate for such harmonics while maintaining control over the reactive power supplied by the network, the primary current control to dampen the transformer's starting current and the
15 control of the magnitude of the secondary voltage using a single-phase Active Power Conditioner Transformer (TAAP).
As shown in Fig. 5, the single phase magnetic configuration TAAP {23} is formed by three branches. One branch consists of the primary winding {24} and the bypass compensation winding {25}. The primary winding is connected to a mains voltage 20 with harmonics v1, 'represented by (4), where V is the magnitude of the fundamental component and Vy is the magnitude of each harmonic component. The magnetic flux generated by this winding contains all the harmonic components present in the voltage. In a typical transformer, these harmonic components would induce a similar voltage waveform vh 'in the secondary winding {26}. Meanwhile, the secondary winding is connected to a non-linear load {27} that would absorb the harmonic current i1 /, represented by (5), while the fundamental component,. It should be noted, this harmonic current would also be present if the load were pure resistive and v1, f had harmonic components. The harmonic current absorbed by the load would generate an FMM on the busbar of the transformer that would be consistent with the load current. Since branches {24} and {27} 30 are magnetically in parallel, a harmonic current i1 / would be generated in the primary winding. Since {24} and {25} are equivalent to a magnetic series circuit and therefore
they represent a magnetic sum of FMMs in this branch, the objective of the bypass winding {25} is to generate the harmonic components of the FMM such that {24} generates only the fundamental component and, therefore, to absorb purely sinusoidal current from the network . This is achieved by controlling the current; 121 through {25}, as shown
5 in (6). In this way, the current waveform required in the auxiliary winding is generated, which produces the FMM necessary for the current in {24} to be purely sinusoidal. In addition, control over the reactive power required from the primary winding can be achieved by supplying this reactive power through {25}, that is, by changing the phase angle e, as shown in (6).
10 The three-phase converter {29} would process the corresponding reference signal to control the current in phase 'a', connected to winding {25}. On the other hand, according to (6), this phase would be absorbing fundamental current from the primary coil to charge the OC Cdc {3D} bus capacitor to maintain a constant OC voltage, Vdc.
To attenuate the voltage harmonics in the secondary winding due to non-sinusoidal flow
15 generated by the primary winding, the winding of the central branch {26} would act as a series equivalent circuit to compensate, according to (7), the harmonic components of the magnetic flux generated by the harmonic voltage. Thus, the resulting flow in {27} is purely sinusoidal and generates a sinusoidal voltage v1 /. On the other hand, according to (7), coil {26} can induce extra sinusoidal flow through Ve to increase or decrease the component
20 fundamental flow that flows to the secondary coil in order to compensate for fundamental voltage variations.
The converter {29} controls the induced voltage at {26}. The neutral point between {25} and {26} is connected to phase 'c' of the converter and the required reference signal is applied through a controller that allows both windings to be shared at a common point.
25 The equivalent electrical circuit shown in Fig. 6 represents the single phase operation of the TAAP as UPQC, as indicated in equations (4) to (7). As a result, this circuit generates a secondary sinusoidal voltage and a primary sinusoidal current, which, in addition, is in phase with the primary voltage.
Y"'''''
(4)
vI: = Vsin (wt) + I Vy sin (ywt + ey)
and Z
y = <XI
(5)
il l = Isin (wt +9) + I iysin (ywt + 9y)
y = 2
y = <XI
il f = / 11sin (wt + 9) + ¿iy sin (ywt + 9y) (6)
y = 2
y = oo
vl ~ = ~ sin (wt) -¿ Vy sin (ywt + By) (7)
y = z
The system control architecture is presented in Fig. 7 and Fig. 8, consisting of two controllers, the bypass compensation controller and the series compensation controller. The series compensation scheme is shown in Fig. 7, which consists of two parts; control of the magnitude of the secondary voltage marked {31} and harmonic compensation 5 of the secondary voltage {32}. The magnitude of the secondary voltage V1 / is kept constant through a proportional-integral controller PI, achieving the reference voltage of the secondary, Vh l *. The resulting reference signal is multiplied by the synchronization secondary voltage signal without (wt) 1 / to achieve a phase compensation of the magnitude of the secondary voltage. Meanwhile, the harmonics of the secondary voltage are
10 compensate through a proportional resonant controller (PR) set to the required compensation frequencies, that is, 2w to nw, with the reference secondary voltage harmonics V1 31_h · set to zero. The resulting reference voltages are added together to obtain the induced voltage required in the series compensation winding, which is the reference voltage for the branch 'a' with respect to the branch 'e' of the converter {29}.
The bypass compensation controller, which is shown in Fig. 8, consists of four controllers; two controllers control the fundamental component of the primary current {33} and {34}, respectively, one controller compensates for the harmonic components
{36} and a bypass winding current controller {35} calculates the current of
required reference from previous drivers. The DC bus voltage regulator {33} 20 will achieve an average constant voltage value on the DC bus of the VdC · converter by absorbing active power from the primary side of the transformer. A PI controller determines the charge current of the capacitor required, which is synchronized with the primary primary voltage, without (wt) 1 /, to achieve the reference of primary charge current i1, '.. This reference current is compared with the current feedback of the primary winding 25 i1, 'and is processed in a fundamental frequency tuned PR controller, W, to obtain the fundamental bypass current required to achieve a constant DC bus voltage, maintaining a zero reactive power at the primary winding and achieve damping to the primary current during transients. The primary harmonic currents are
compensate through a tuned PR regulator at compensation frequencies
required, setting the reference current i11 1_h to zero and thus producing the required harmonic bypass compensation currents. The combined compensation current i1./ "is controlled by a PR controller to obtain the voltage
5 converter bypass output v1 /
The decoupling of the tension of the branch 'a' and branch 'b' with respect to the branch 'c' is achieved by determining the duty cycle of each branch in the Pulse Width Modulator (PWM), decoupling the control of all phases by sharing switching states between the different phases. The primary frequency w is obtained through a synchronizer of the type DSOGI FLL (Double Second-Order Generalized Integrator Frequency Locked Loop). The DSOGI is used to calculate the positive and negative sequence components (PNSC-Positive / Negative Sequence Calculation block) of the voltage and thus determine the synchronization signal without (wt) 1 /, the magnitude of secondary voltage V131 and the secondary voltage of signal synchronization without (wt) 131, required for controllers
15 compensation discussed above.

权利要求:
Claims (4)
[1]

one. An Active Power Conditioner Transformer with single phase configuration,
characterized by having a closed three-column magnetic core, such as the
5 shown in Figure 5, in which a primary winding {24} and a winding
secondary {27} are rolled in two different core columns; an auxiliary winding
of regulation of the magneto-motive force developed by the primary winding {25} is
wind in the same column as the primary winding {24}; an auxiliary winding of
flow regulation concatenated by the secondary winding {26} is wound in the
the column that is free; and a three-phase power converter {29} controls both the
current in the auxiliary winding regulating the magneto-motor force of the
primary winding (i1 /) And as the voltage in the auxiliary winding of flow regulation
concatenated by the secondary winding (v1 /).
[2]
2. The Active Power Conditioner Transformer claimed in 1, characterized
fifteen because the current in the auxiliary winding regulating the magneto-motive force
of the primary winding (i1 /) is controlled by a power converter
single-phase and the voltage in the auxiliary winding regulating the flow concatenated by
the secondary winding (v 1 /) is controlled by another power converter
single-phase, both converters being single-phase converters particular cases of the converter
twenty generic polyphase represented in Figure 4 and having its elements of
energy storage {21} or energy source / storage {22}
interconnected with each other, forming a link circuit {10} to ensure balance
of power
[3]
3. An Active Power Conditioner Transformer with three phase configuration,
25 characterized by being constituted by three active transformers conditioners
of Power with single-phase configuration, as claimed in 1 or 2, in which
the three primary windings and the three secondary windings of the system are
interconnect respectively in star or triangle configuration depending on the
network and load requirements.
JO Four.The Active Power Conditioner Transformer claimed in 3, characterized
because the three auxiliary windings regulating the magneto-motive force of the
primary winding {25} interconnect in star or triangle, its current being
controlled by a three-phase power converter, and the three auxiliary windings
of regulation of the flow concatenated by the secondary winding {26}, its voltage being controlled by another three-phase power converter, both three-phase converters being derived from the generic polyphase converter represented in Figure 4 and having their energy storage elements {21} or the energy source / storage {22} interconnected with each other, forming a link circuit {10} to ensure power balance.
[5]
5. The Active Power Conditioner Transformer with three-phase configuration, characterized in that three closed three-column magnetic cores, as shown in Figure 5, are physically stacked to form a single armored three-phase structure, as a particular case of the generic structure shown in Figure 2, in which there are three primary windings {24}, three secondary windings {27}, three auxiliary windings regulating the magneto-motor force developed by the primary windings {25} and three auxiliary windings regulating the flow concatenated by the secondary windings {26}, and in which the three auxiliary windings regulating the magneto-motive force of the primary winding {25} are interconnected in a star or triangle, their current being controlled by a three-phase power converter, and the three auxiliary windings regulating the flow concatenated by the secondary winding {26}, its volt being Aje controlled by another three-phase power converter, both three-phase converters being derived from the generic multi-phase converter represented in Figure 4 and having their energy storage elements {21} or the energy source / storage {22} interconnected with each other, forming a circuit link {10} to ensure power balance.

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同族专利:

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公开号 | 公开日

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ES2684108B1|2019-06-13|

引用文献:

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公开号 | 申请日 | 公开日 | 申请人 | 专利标题

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GB617706A|1943-10-18|1949-02-10|Const Electr|Static transformer for arc welding|

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US3665150A|1969-11-21|1972-05-23|Ind Sigma Sa De Cv|Electrical welding machine having amperage control transformer|

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US3990030A|1975-08-11|1976-11-02|Standex International Corporation|Pincushion correction transformer|

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CN201444443U|2009-01-16|2010-04-28|魏明|Transformer capable of controlling part of voltage|WO2021225750A1|2020-05-08|2021-11-11|Raytheon Company|Actively-controlled power transformer and method for controlling|

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优先权:

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申请号 | 申请日 | 专利标题

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ES201730484A|ES2684108B1|2017-03-30|2017-03-30|Active Transformer Power Conditioner|ES201730484A| ES2684108B1|2017-03-30|2017-03-30|Active Transformer Power Conditioner|