Control method and control device used for shunting of power supply units

FIELD: electricity.

SUBSTANCE: control method for shunting of power supply units includes the following steps: measurement of the first three-phase output eclectic signal; calculation of the first direct and reverse sequences of the first three-phase output eclectic signal; generating of the preset components for direct and reverse sequences of phases in order to perform automatic compensation for the components of the first direct and reverse sequences thus outputting components of the second direct and reverse sequences; summing-up of the second direct and reverse sequences and output of the second three-phase output eclectic signal in the preset mode.

EFFECT: reducing output voltage ripple.

10 cl, 10 dwg

 

The technical field to which the invention relates.

The present invention relates to the topological structure of the cascaded inverter. More specifically, the present invention relates to a control device and control method of topological structure, which is used in the bypass power supplies.

Description of technical solutions from the related field of technology

Currently, conventional inverter medium, high voltage is used as a device that provides a nominal voltage of power supply units, and, in addition, its topological structure is generally adapted to reduce the level of harmonics of the output voltage. In the topological structure of each phase is composed of several series-connected power supplies with lower nominal voltage and allows you to produce high voltage. However, due to the large number of power supplies system reliability may be low, because the possible failure of one or more power supplies. Currently, the failed power supply must be bypassed, and the remaining power control for the issuance of three-phase voltage for a continuous operation of the entire system with a cascade inverter. When bypass of the failed power source control method you want to change, and the hache three-phase output voltage is unbalanced.

In devices of the prior art use three common technical solutions. The first is to bypass the same stages. When failures occur in several power supplies in the same phase, control respective power supplies in the same cascade of two other phases, for shunting them, even if they are intact, so that the same number of power supply units in each phase provides. However, this method of control outputs from a working power supply and significantly reduces the output voltage. The second way is to reduce the control voltage. Namely, reduce the control voltage of the phase having less than a failed power supplies, to ensure the equality of the output voltages of the phases. However, when using this method not only significantly decreases the output voltage, but also very different output power control units, and they have different load. The third way is the offset voltage of the neutral. I.e. when the failure in one or more of the power in one phase due to a change in the phase difference between each phase provides the opportunity to support still balanced line output voltage even when unbalanced phase voltages (since the load is applied line voltage). On the however, this method of control requires consideration of all possible combinations of power supplies continueth in each phase, and it is necessary to calculate in advance the phase angle between every two phases for each combination after bypass surgery. Therefore requires a large amount of memory in the controller. In addition, as should be separate control of each phase, the method is not suitable when using the principle of pulse-width modulation of the spatial vector SINV (SVPWM). Therefore its use is limited from the point of view of vector control Converter.

In connection with the above, many experts in the industry are looking for ways to solve the task management cascade inverter to bypass power supplies, efficient solution and eliminating the disadvantages and inconveniences of the above method of control.

The ESSENCE of the INVENTION

Given the shortcomings of the control method, known from the prior art, is used to bypass the power supplies, the present invention proposes the relevant device and method of control.

In accordance with one aspect of the present invention proposed a control device that is used to bypass the power supplies suitable for balancing a three-phase output voltage of the cascaded inverter. The control unit contains:

measuring module for measuring three-phase output voltage is deposits;

a computing module to compute a component of the negative sequence three-phase output voltage;

a compensation module for providing the selected component in the reverse sequence and automatic compensation based component of the reverse sequence generated by the computing module according to a given component of the reverse sequence to output the compensated component of the reverse sequence, and

an output module for adding the offset component of the reverse sequence with the task of three-phase output voltage and output a new three-phase output voltage using the specified modulation mode.

Preset mode modulation is sinusoidal pulse-width modulation (cpwm nominals (SPWM) or pulse-width modulation of the spatial vector SINV (SVPWM). In accordance with another aspect of the present invention, a method of control that is used to bypass the power supplies suitable for balancing a three-phase output voltage of the cascaded inverter. The control method includes the following operations:

measurement of three-phase output electrical signal using a sensor module;

accordingly, the calculation of the components of the direct and inverse is posledovatelnostei three-phase output electrical signal using the processing module;

the formation of defined components of the forward and reverse sequences using the compensation module and automatic compensation components of the forward and reverse sequences for introduction of new components of the forward and reverse sequences and

the addition of new components of the forward and reverse sequences and conclusion a new three-phase output electrical signal using a predetermined modulation mode.

Preset mode modulation is sinusoidal pulse-width modulation (cpwm nominals (SPWM) or pulse-width modulation of the spatial vector SINV (SVPWM).

BRIEF DESCRIPTION of DRAWINGS

Various aspects of the present invention will be more clearly described and understood in connection with the following characteristic variant implementation of the invention with reference to the accompanying drawings. In the drawings:

figure 1 shows a simplified diagram of a method of managing a cascade inverter to bypass power supplies of the prior art, figure 2 shows a simplified diagram of another method of controlling the cascade inverter to bypass power supplies of the prior art, figa and 3B shows a simplified diagram of another method of controlling the cascade inverter to bypass the various power supplies of the prior art,

figure 4 shows b is OK-the precedence diagram method control cascade inverter to bypass power supply units in accordance with a variant implementation of the invention,

figure 5 shows an embodiment of the control output voltage based on the control method, shown in figure 4, figure 6 shows another particular variation control of the output voltage based on the control method, shown in figure 4, figure 7 shows the block diagram of the sequence control method cascade inverter to bypass power supplies in accordance with another variant of realization of the invention, Fig shows an embodiment of the control output voltage based on the control method shown in Fig.7 and Fig.9 shows another particular variation control of the output voltage based on the control method shown in Fig.7.

DETAILED DESCRIPTION

In order to make the description of the invention a more detailed and complete, below are different ways of implementing the invention with reference to the accompanying drawings. The same or similar elements in the drawings have the same item numbers. However, the usual experts in the art should understand that the embodiments of the invention described below do not limit the scope of the invention. Moreover, the accompanying drawings are only illustrative and are not within the scope.

In sublattice the service description and claims of this application, the phrase "connected with" can do to treat that component is connected to another component, not directly, but through another component, or that it is connected directly to another component without other intermediate components.

In the detailed description and claims of this application, except for paragraphs, definitely limited by the context, all references to objects also involve plural.

The words "about", "about" or "approximately" are used to identify any minor deviations that do not affect the essence of value. In embodiments of the invention, the error value determined by the words "about", "about" or "approximately", is within 20%, preferably 10% and better still 5%, unless otherwise specified the exact meaning.

As noted above, the topological structure of the cascade inverter, each phase is formed by the serial connection of multiple power supplies. During normal operation, each power supply three-phase output voltage is maintained symmetrical (i.e. line voltage between two adjacent phases is equal to the load power supply line voltage. However, failure occurs at one or more power supplies failed power supply units must be bridged. After shunting the appropriate method supported by almost symmetric the second three-phase output voltage.

In addition, we note that in the description of the present invention, the terms "three-phase output voltage" and "component sequence" means the physical or voltage commands (signals).

1 shows a diagram of application of the known method of control in a cascade inverter to bypass power supplies.

In accordance with the scheme of figure 1 is the connecting line between points a and represents phase A, which includes 9 connected in series power supplies A1-A9. The connecting line between points b and O is the phase, which includes 9 connected in series power supplies B1-B9. The connecting line between points C and O is the phase, which includes 9 connected in series PSUs C1-C9. The line segments AB, BC and CA are line voltage. In case of failure of power supply A3 in phase And the power supply A3 continuum. In this case, since the number of power supplies in the normal state in the phase And decreased from 9 to 8, there is a reduction of the phase voltage of phase A. Therefore there is the asymmetry of the three-phase line voltages AB, BC and CA.

In order to solve the problem, when using conventional control method continuum power in the other two phases, namely the blocks B3 and C3, shown in figure 1 and the corresponding power supply unit A3. So, e is whether the voltage of each phase a, B and C is equal to U, then each power supply provides a voltage 1/9U. That is, after the power supply A3, B3 and C3 bridged, phase voltage of each of the three phases will be reduced to 8/9U. Although the control method allows to achieve the balancing of tension, a working power supply units B3 and C3 are knocked out of action and in addition the output voltage is considerably smaller.

Figure 2 shows a simplified schematic of an application of another conventional control method in a cascade inverter to bypass power supplies.

In accordance with figure 2, assuming the source phase voltages in phases a, b and C is equal to U, each power supply provides a voltage 1/9U. When failure of the power supply unit A3 in phase a and power supply B2 phase In the power supply A3 and B2 continuum. Since the number of power supplies in the normal state in phases a and b decreased from 9 to 8, the phase voltage of phase a and b become smaller. Therefore, there is the asymmetry of the three-phase line voltages AB, BC and CA.

In order to solve the problem, reduce controllable voltage phase using the normal method of control without output from a working power supply. So controlled voltage phase is reduced to 8/9U. However, this method of control also leads to a significant reduction of the output voltage and, in addition, the output power of power supply units are significantly different, and power supplies have different load. Furthermore, the method of control requires that each phase was managed. Therefore, it is incompatible with the principle of pulse-width modulation of the spatial vector SINV (SVPWM).

On figa and 3B shows a simplified schematic of an application of another conventional method of controlling a cascade inverter to bypass various power supplies.

In accordance with figa failure of one power supply unit in phase a (the total number of power supply units is reduced from 9 to 8) output voltages of three phases are supported symmetrical as possible, by changing the phase angle (phase difference) between every two neighboring phases. So, figa phase difference between phases a and C is 123,6 hail and between phases a and b also 123,6 deg. However, to ensure symmetry line voltage phase difference between phases b and C must be of 112.8 degrees. Therefore, although the phase voltage of phase a is different from the phase voltages of phases b and C, three-phase output line voltage AB, BC and CA are the same (thus, each of the line segments on figa has a length of 15).

As can be seen from FIGU, failure of any two power supply units in phase a (the total number of power supply units is reduced from 9 to 7) using the same method of controlling the output voltage of the three phases are also supported symmetrical as possible, the way the changes in the phase difference between two adjacent phases. So, figv phase difference between phases a and C is 127,1 hail and between phases a and b also 127,1 deg. However, for symmetry line voltage phase difference between phases b and C must be 105,8 deg. Therefore, although the phase voltage of phase a is different from the phase voltages of phases b and C, three-phase output line voltage AB, BC and CA are the same (each of the line segments on FIGU has a length 14,35).

However, as for Figo and figv control method requires consideration of all possible combinations counterweigh power supplies for each phase, and it is necessary to calculate in advance the angle between every two phases after shunting for each combination. Since in each phase there are many variants of failures of power supply units, and their combinations give a large number of angles that define a particular phase difference between phase a and phase b, between phase b and phase C and between phase C and phase A, and this requires a large amount of memory in the controller. In addition, the angle value is usually floating and requires more space for storage in memory. On the other hand, the control method also requires that each phase was managed and it is incompatible with the principle SINV (SVPWM). Therefore its use is limited from the point of view of vector control Converter.

Figure 4 shows the block diagram of the sequence of operations of the JV is soba control cascade inverter to bypass power supply units in accordance with a variant implementation of the invention. As shown in figure 4, the first step S11 of the control method according to the invention provides for measurement of three-phase output voltage of the cascaded inverter. Next, in step 813 calculate the component of the negative sequence measured three-phase output voltage. It should be noted that the components of the forward and reverse sequences of voltage (or current) (in three-phase four-wire circuit, moreover, possible component of zero sequence) are used for the decomposition of asymmetric three-phase voltage or current for the circuit analysis. Ideally symmetrical three-phase voltage (or refers to a regulated to ensure symmetry), so the component of the negative sequence voltage is equal to zero. Failure in the system three-phase voltage becomes asymmetric. When this component of the negative sequence has a certain amplitude. It is seen that it is possible decomposition of any three phase voltage (or current) into components of direct and reverse order. When supported symmetrical three-phase voltage (or current)three-phase voltage is only component of the direct sequence and component of the negative sequence zero. If three-phase voltage (or current) asymmetric, traffas the second voltage includes not only a component of the direct sequence, but also part reverse sequence having a certain amplitude.

Next, in step S15 form specified component of the reverse sequence to provide automatic compensation component in reverse order and then output offset component of the reverse sequence. Finally, in step S17 offset component of the reverse sequence is added to the reference three-phase output voltage, and output a new three-phase output voltage, modulated in the specified mode.

According to a particular variant of realization of the specified reverse sequence in operation S15 is equal to zero. However, the invention is not limited to this. For example, in other embodiments of the invention can be close to zero boundary values specified reverse order.

In accordance with another particular variant of the invention the automatic compensation component reverse order perform the above step S15 by using a compensator. The compensator includes, without limitation, the proportional compensator P (P), proportional-integral compensator PI (PI), proportional-resonant compensator PR (PR) and proportional-integral-differential compensator PI IS (PID). It should be noted that the compensator allows you to directly compensate for the component of the negative sequence found in step S13. It also enables automatic compensation value calculated component of the reverse sequence after the coordinate transformation. For example, three-phase coordinate system (hereinafter denoted abc) replace the two-phase static coordinate system (hereinafter denoted αβ). Alternatively, the coordinate system abc replace the two-phase coordinate system (hereinafter referred to dq).

In accordance with another variant of the invention the specified modulation mode is sinusoidal pulse-width modulation (cpwm nominals (SPWM) or pulse-width modulation of the spatial vector SINV (SVPWM).

Before to examine in detail a number of the following variants of the invention will denote the three-phase output voltage at 25 coordinate system abc Uout(abc)constituting direct sequence three-phase output voltage - U(1)(abc)making negative sequence three-phase output voltage - U(2)(abc)the desired value of the three phase output voltage - Uout(abc)three-phase output current Iout(abc)constituting direct sequence three-phase output current - I (1)(abc)making negative sequence three-phase output current I(2)(abc)the desired value of the three phase output current Iout(abc)*. Similarly, three-phase output voltage in the coordinate system αβ denote Uout(αβ)constituting direct sequence three-phase output voltage - U(1)(αβ)making negative sequence three-phase output voltage - U(2)(αβ)the desired value of the three phase output voltage - Uout(αβ)*three-phase output current Iout(αβ)constituting direct sequence three-phase output current I(1)(αβ)making negative sequence three-phase output current I(1)(αβ)the desired value of the three phase output current Iout(αβ)*. Three-phase output voltage in the coordinate system dq denote Uout(dq)constituting direct sequence three-phase output voltage - U(1)(dq)making negative sequence three-phase output voltage - U(2)(dq)the desired value of the three phase output voltage - Uout(dq)*three-phase output current Iout(dq)constituting direct sequence three-phase output current I(1)(dq)making negative sequence three-phase output is about power - I(2)(dq)the desired value of the three phase output current Iout(dq)*.

Figure 5 shows a typical embodiment of the control output voltage based on the control method shown in figure 4.

In accordance with 5 way control provides controlled three-phase output voltage Uout(abc)modulated mode cpwm nominals (SPWM). In this embodiment of the invention measure the three-phase output voltage Uout(abc). Next, calculate and allocate component U(2)(abc)reverse sequence. After that perform automatic compensation component U(2)(abc)return sequence (for example, setting the value specified component in the reverse order of 0). Offset component of the reverse sequence is added to the desired value Uout(abc)*three-phase output voltage. Ultimately, three-phase output voltage Uout(abc)modulate mode cpwm nominals (SPWM).

Specialists in the art it is clear that the scheme shown in figure 5, illustrates not only how to control the three-phase output voltage at the bypass power supply unit in the cascade inverter, but also shows a control device made in accordance with this act shall obom. More specifically, the control device includes measuring, computing, compensation and output modules. The measuring module measures the three-phase output voltage Uout(abc). Computing module computes the component U(2)(abc)negative sequence three-phase output voltage obtained from the measurement module. The compensation module is used to produce a given component relative to 0 reverse and automatic compensation component U(2)(abc)reverse sequence obtained from the processing module, in accordance with the set value for output offset component of the reverse sequence. The output module provides the addition of the offset component of the negative sequence three-phase output voltage and the output of the new three-phase output voltage Uout(abc)modulated mode cpwm nominals (SPWM).

Figure 6 shows another particular variation control of the output voltage using the control method shown in figure 4.

In accordance with 6 way control allows the output of the controlled three-phase output voltage Uout(abc)modulated mode SINV (SVPWM). In this embodiment of the invention measure the current traffas the second output voltage U out(abc)and then calculate and allocate component U(2)(abc)reverse sequence. In contrast to figure 5, the control method shown in Fig.6, provides coordinate transformation 3/2 (i.e. conversion of a coordinate system abc in the coordinate system αβ) calculated component U(2)(abc)reverse order to obtain the component of U(2)(αβ)reverse order in the two-phase static coordinate system. After that perform automatic compensation component U(2)(αβ)return sequence (for example, by setting a specified relative to the 0 component of the reverse sequence). Offset component of the reverse sequence is added to the desired value Uout(αβ)*three-phase output voltage. Then the three-phase output voltage Uout(abc)modulate mode SINV (SVPWM). Here in the modulator SINV (SVPWM) must be entered component in the coordinate system αβ. Therefore, before automatic compensation component of the negative sequence U(2)(abc)you need to convert it to component U(2)(αβ)in the coordinate system αβ.

7 shows a block diagram of the sequence control method cascade inverter to bypass power supplies in accordance with another VA what Ianto implementation of the invention.

According to Fig.7. in this embodiment of the invention first, in step S21 perform the measurement of the first three-phase output electrical signal cascade inverter. Here the electric signal does not have to be a voltage signal. Next, in step S23 calculate the components of the first forward and reverse sequences of the first three-phase output electrical signal. After that, in steps S251 and S253 form specified component of direct sequence and perform an automatic compensation of the calculated component of the first direct sequence, and then form a given component reverse order and perform automatic compensation calculated component of the first reverse sequence to output the components of the second forward and reverse sequences. Finally, in step S27 stack offset components of the second forward and reverse sequences, and output the second three-phase output electrical signal modulated in a predetermined mode.

It should be noted that the steps S251 and S253 are not strictly ordered. First, possible automatic compensation component of the first direct sequence, and then part of the first reverse order. On the other hand, automatic comp is Nazia first component of the first reverse sequence, and then the first direct sequence. In addition, the simultaneous automatic compensation of these components.

According to another particular variant of the invention the specified modulation mode is sinusoidal pulse-width modulation (cpwm nominals (SPWM) or pulse-width modulation of the spatial vector SINV (SVPWM). In addition, if the selected modulation cpwm nominals (SPWM), given as a component of direct sequence represents the desired value of the first three-phase output electrical signal in a three phase system of coordinates.

According to a particular variant of the invention, a given component of the reverse sequence is equal to 0.

On Fig shows an embodiment of the control output voltage using the control method shown in Fig.7.

In accordance with Fig method of control allows the output of the controlled three-phase output voltage Uout(abc)in the modulation mode SINV (SVPWM). In this variant implementation of the invention, the measured value is three-phase output current Iout(abc). However, the invention is not limited to this. For example, as the measured values it is also possible three-phase output voltage Uout(abc).

Here specifically measure the three-phase output is th current I out(abc)cascade inverter and accordingly calculate the components of I(1)(abc)and I(2)(abc)the first forward and reverse sequences of the three-phase output current. Then perform the conversion 3/2 component of I(1)(abc)direct sequence in the coordinate system abc in part I(1)(αβ)the first direct sequence in the coordinate system αβ. After the formation of a given component of Iout(αβ)*direct sequence perform an automatic compensation of I(1)(αβ). Simultaneously convert 3/2 component of I(2)(abc)reverse order in the coordinate system abc in part I(2)(αβ)the first reverse order in the coordinate system αβ. After the formation of a given component of the negative sequence, zero, perform automatic compensation component of I(2)(αβ). Finally, put offset components of the second forward and reverse sequences, and output the second three-phase output electrical signal, modulated mode SINV (SVPWM).

In some other embodiments of the invention can output the controlled three-phase output voltage, a modulated mode cpwm nominals (SPWM). For example, automatically direct compensation calculated costs is appropriate I (1)(abc)and I(2)(abc)the first forward and reverse sequences. Then summarize the offset components of the second forward and reverse sequences and three-phase output voltage modulate mode cpwm nominals (SPWM). Thus, the conversion 3/2, shown in Fig saved, and only after the addition of the second-pillar forward and reverse sequences after automatic compensation convert 2/3 (i.e. transformation from the coordinate system αβ in the coordinate system abc). Then the three-phase output voltage modulate mode cpwm nominals (SPWM).

In accordance with another particular variant of the invention, the control method additionally includes coordinate transformation abc/dg performed respectively for the components of the first forward and reverse sequences to obtain the corresponding components in the two-phase rotating coordinate system for automatic compensation.

Figure 9 shows another particular variation control of the output voltage using the control method shown in Fig.7.

As Fig, control method, shown in figure 9, allows the output of the controlled three-phase output voltage Uout(abc)modulated mode SINV (SVPWM). In this embodiment of the invention as the measured value is three-phase output current I out(abc). However, this does not limit the invention. For example, it is possible to measure three-phase output voltage Uout(abc).

Figures 9 and 8 differ in that figure 9 after conversion 3/2 components of I(1)(abc)and I(2)(abc)respectively the direct and inverse sequences perform additional coordinate transformation αβ/dq components of I(1)(αβ)and I(2)(αβ)two-phase static coordinate system to obtain a rotating values of I(1)(dq)and I(2)(dq). Then, after forming a given component of the direct sequence perform an automatic compensation of the rotating values of I(1)(αβ)calculated component of the first direct sequence. After formation of the set relative to the 0 component of the reverse sequence perform an automatic compensation of the rotating values of I(2)(dq)calculated component of the first reverse order. Since the direct addition of the components of the forward and reverse sequences in a two-phase rotating coordinate system (the coordinate system dq) on the compensated outputs of the computing modules, it is necessary to perform coordinate transformation dq/αβ to obtain components in the coordinate system αβ, and these components ultimately summarize and display with what adularia mode SINV (SVPWM).

In some embodiments of the invention may be combined conversion 3/2 and conversion αβ/dq by using the direct conversion of the abc/dq. Therefore, you can also receive a rotating values of I(1)(dq)part of the first direct sequence and rotating the magnitude of I(2)(dq)part of the first reverse order in the two-phase rotating coordinate system.

In some embodiments of the invention may also use modulation mode cpwm nominals (SPWM) to output the controlled three-phase output voltage. For example, the coordinate transformation dq/abc perform, respectively, for second-pillar forward and reverse sequences after automatic compensation for obtaining components in three-phase coordinate system, and the output of the second three-phase output voltage after performing the addition.

When using the device and method of control in accordance with the invention when the bypass power supply units for automatic compensation component of the negative sequence three-phase output voltage, a cascade inverter still allows you to maintain the symmetry of the output voltages. In addition, the present invention provides automatic compensation is relevant to the military components of the forward and reverse sequences of the three-phase output electrical signal (for example, voltage or current) and the offset component of the direct sequence then added to the offset component of the reverse sequence to ensure the balancing of the three-phase output electrical signal cascade inverter. Compared with the prior art implementations of the present invention can not only effectively use all good power supplies, but also provide a small decrease in output voltage and even at almost constant output voltage. In addition, the control method is applicable not only to the modulation mode cpwm nominals (SPWM), but also in the mode SINV (SVPWM). Therefore, it is highly compatible with vector control Converter.

As mentioned above, the characteristic of the embodiments described with reference to the accompanying drawings. However, the person skilled in the art should be understood that in these embodiments, various modifications and changes within the essence and scope of the invention. These modifications and changes should be subject to the formulas of the present invention.

1. A control device that is used to bypass the power supplies for balancing a three-phase output voltage of the cascaded inverter, containing
the measure concentration is compulsory module for measuring three-phase output voltage;
a computing module to compute a component of the negative sequence contained in a three-phase output voltage;
the compensation module to receive a given component reverse order and perform automatic compensation based component of the reverse sequence generated by the computing module in accordance with a given component of the reverse sequence to output the compensated component of the reverse sequence, and
an output module for adding the offset component of the reverse sequence with the task of three-phase output voltage and output a new three-phase output voltage using the modulation mode and modulation mode is a mode sinusoidal pulse-width modulation (cpwm nominals (SPWM) mode or pulse-width modulation of the spatial vector SINV (SVPWM).

2. The control device according to claim 1, in which when SINV (SVPWM) computing module is additionally designed to transform coordinates abc/αβ calculated component reverse order to obtain the component reverse order in the two-phase static coordinate system and the compensation module provides automatic compensation component reverse the consequences of the successive two-phase static coordinate system in accordance with a given component of the reverse sequence to output the compensated component of the reverse sequence.

3. The control method used to bypass the power supplies for balancing a three-phase output voltage of the cascaded inverter, including:
the dimension of the first three-phase output electrical signal using a sensor module;
calculating respectively the components of the first forward and reverse sequences of the first three-phase output electrical signal using the processing module;
the formation of defined components of the forward and reverse sequences of phases using a compensation module and perform automatic compensation components of the first forward and reverse sequences for output components of the second forward and reverse sequences; and
the addition of second-pillar forward and reverse sequences and the output of the second three-phase output electrical signal in the modulation mode, in which
the modulation mode is a mode sinusoidal pulse-width modulation (cpwm nominals (SPWM) mode or pulse-width modulation of the spatial vector SINV (SVPWM).

4. The control method according to claim 3, in which when using cpwm nominals (SPWM) specified component of the direct sequence represents the desired value of the first three-phase output electrical signal in a three phase system within the inat.

5. The control method according to claim 3, in which when SINV (SVPWM) control method additionally includes:
accordingly, the coordinate transformation abc/αβ calculated components of the first forward and reverse sequences to obtain the corresponding static values constitute the first direct and reverse sequences in two-phase static coordinate system to perform automatic compensation.

6. The control method according to claim 5, in which a given component of the direct sequence is the desired value of the first three-phase output electrical signal in the two-phase static coordinate system.

7. The control method according to claim 3, further including:
accordingly, the coordinate transformation abc/dq calculated components of the first forward and reverse sequences to obtain the corresponding rotating components values of the first forward and reverse sequences in a two-phase rotating coordinate system to perform automatic compensation.

8. The control method according to claim 3, in which when using cpwm nominals (SPWM) the operation of addition extras includes:
accordingly, the coordinate transformation dq/abc compensated second components of the forward and reverse sequences for the floor of the treatment components values of the second forward and reverse sequences in three-phase coordinate system and then the output of the second three-phase output electrical signal after the addition.

9. The control method according to claim 3, in which when SINV (SVPWM) the operation of addition extras includes:
accordingly, the coordinate transformation dq/αβ offset components of the second forward and reverse sequences to obtain the static values of the components of the second forward and reverse sequences in the two-phase static coordinate system and then the output of the second three-phase output electrical signal after the addition.

10. The control method according to claim 3, in which a given component of the negative sequence zero.



 

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2 dwg

FIELD: electricity.

SUBSTANCE: device comprises an inlet terminal 1 for connection of a source of signal setting, a summator 2, an integrator 3, the first 4, second 5 and third 6 relay elements, the first 7, second 8, third 9, fourth 10, fifth 11, sixth 12, seventh 13, eighth 14 and ninth 15 comparators, the first 16, second 17 and third 18 dynamic D-triggers, buses of voltage of a circuit of phases of A, B, C-terminals 19, 20, 21, the first 22-1, the second 22-2 and third 22-3, the fourth 22-4, the fifth 22-5, the sixth 22-6, the seventh 22-7, the eighth 22-8 and the ninth 22-9 power switches, a three-phase load with a zero outlet 23, the first 24-1, the second 24-2, the third 24-3, the fourth 24-4, the fifth 24-5, the sixth 24-6, the seventh 24-7, the eighth 24-8 and the ninth 24-9 sensors of conductivity, an arithmetic-logical device 25, a terminal "reset" 26, the first and second selectors of pulse duration 27 and 29, "Emergency disconnection outlet" 28, a terminal "Duplicating outlet of protection" 30.

EFFECT: increased reliability of an AC voltage controller by diagnostics of failures in power switches.

5 dwg

FIELD: physics.

SUBSTANCE: frequency-pulse duration alternating voltage controller has an adder, an integrator, a relay element, comparators, dynamic D flip-flops, switch elements (thyristors), load resistors connected in a star circuit with a neutral terminal, a setting signal source and a three-phase voltage source. Said alternating current controller includes three dynamic D flip-flops, which enable to generate 'packets' of sinusoidal voltage across the load with a whole number of periods of mains voltage.

EFFECT: high energy efficiency.

5 dwg

FIELD: transport.

SUBSTANCE: invention refers to automatic voltage control devices in overhead system on electrified railway transport. Device includes two speed control units of moving object, speed detecting unit of moving object, setting device of limit speed value of moving unit, formation unit of maximum voltage stabilising level, OR element, and transformer commands shaping unit. Output of each speed control unit is connected to the first input of the appropriate speed detecting unit. The second input of each of speed detecting units is connected to output of setting device of limit speed value. Output of each detecting unit of limit speed value is connected to input of shaping unit of maximum voltage stabilisation level at the sub-station by means of OR element. Output of shaping unit of maximum voltage stabilisation level at substation is connected to the third input of shaping unit of transformer commands.

EFFECT: higher reliability.

2 dwg

FIELD: electricity.

SUBSTANCE: invention may be used in frequency-controlled electric drive for control of three-phase voltage and frequency at the outlet of matrix converter, which is arranged on 9 transistors in units of array formed by crossings of t=1, 2 three-phase horizontal supply buses and j=1, 2 three-phase vertical buses of load. Transistors are switched with the help of control pulses, which are generated in compliance with equation , where is matrix, with size of 9x6, which is generated with the help of synchronising pulses with duration of π/3, matching intervals, in which interphase voltages of supply grid change in specified range; - six-dimensional vector of width-modulated primary control pulses, which are generated on high bearing frequency as a result of comparison of three-phase system of setting signals of harmonic shape with reference signal. The latter is produced by continuous integration of specified interphase voltages of grid and their inversion every time reference signal reaches specified threshold level.

EFFECT: maintenance of high quality of control in lower part of range with the possibility to establish any values of current shift coefficient at grid input.

2 cl, 3 dwg, 1 tbl

FIELD: electricity.

SUBSTANCE: invention relates to the field of electric engineering and may be used in the industry to control AC motor. System of energy delivery and method of its actuation includes multiple power supply elements, which are electrically connected to machine and multiple windings, comprising one or more primary windings and multiple secondary windings, so that each element is electrically connected to one of secondary windings, and multiple secondary windings are shifted by phase relative to primary windings. Method includes detection of shift angle for carrier for each element in set of power supply elements, and synchronisation, by each element in set of carrier signal with secondary voltage for element on the basis of carrier angle shift detected for the element. Carrier signal for each element controls timing of switching instruments operation in each element.

EFFECT: reduced harmonics developed by operation of power supply element, having bidirectional switching instruments.

24 cl, 8 dwg

FIELD: electric engineering.

SUBSTANCE: as semiconducting switch intended for short-circuiting of one of stator windings of motor when stator windings are connected as delta, two reversible semiconducting switchboards are used, every of which comprises two opposite connected transistors. In the first reversible semiconducting switchboard, collector of the first transistor is connected to emitter of the second transistor and connected to phase of supply grid, and emitter of the first transistor is connected to collector of the second transistor and to outputs of the first and second stator windings, and their common output is intended for connection to phase of supply grid. In the second reversible semiconducting switchboard, collector of the third transistor is connected to emitter of the fourth transistor, and their common output is intended for connection to phase of supply grid, and emitter of the third transistor is connected to collector of the fourth transistor, and their common output is intended for connection of outputs of the second and third stators windings. Common output of the first and third windings is connected to zero of single-phase grid.

EFFECT: increasing reliability and efficiency of device, reduction of its dimensions.

3 dwg

FIELD: electrical engineering.

SUBSTANCE: proposed device comprises two units 1 and 2 to isolate limiting voltage in contact system, units 3 and 4 to measure voltage in said system, OR element 6, unit 16 to calculate voltage level at substation, transformer instruction shapes 17, contact system minimum voltage setters 7 and 8, current overload signal shaper 11, substation current overload unit 15, maximum current setter 14, substation voltage stabilisation signal shaper 10, substation voltage stabilisation signal setter 18, substation transformer voltage metre 19. It incorporates also unit 5 to generate stabilisation voltage up-signal, unit 9 to inhibit stabilisation voltage increase, unit 23 to generate substation voltage stabilization level decrease signal, unit 16 to compute substation voltage level, AND element (13), unit 20 to control stabilisation voltage minimum level, unit 21 to generate signal cancelling voltage stabilisation and cutting in switching unit that switches transformer over to natural characteristic, unit 22 to temporarily delay switching unit and switching unit 23.

EFFECT: possibility to adjust voltage in both overhead contact system and transformer station.

2 dwg

FIELD: electricity.

SUBSTANCE: invention can be used mainly in countryside and suburb nursery gardens which power supply is made from transformer substations (TS) with rather long overhead power lines and at the ends of such lines mains voltage decreases to an unaccepted level thus deteriorating quality of services rendered by the energy service companies. The device consists of two bridge circuits with different conductivity direction for positive and negative alternating voltage half-periods respectively connected in parallel to the mains conductors, each of the circuits include two circuits of the in-series electrolytic capacitor and power transistor. Free outputs of capacitors in the first and second branches of each bridge circuit are connected to the phase and neutral conductors of the mains, at diagonal lines of the bridge circuits there are thyristors ensuring in-series connection of capacitors in each bridge circuit to the mains conductors in the second and fourth quarter-periods of alternating voltage respectively for the first and second bridge circuits and operational control of transistors and thyristors as per the set algorithm is carried out by a control unit for transistors and thyristors.

EFFECT: increase of voltage level.

3 cl, 9 dwg

FIELD: electricity.

SUBSTANCE: invention relates to electrical engineering. Three-phase capacitance transducer for power supply of active load contains two groups of in-series connected diode and storage capacitor and two groups of in-series connected thyristor and integrating capacitor connected in parallel to the respective storage capacitors. At that the two groups of in-series connected diode and storage capacitor are connected to two phases of the three-phase electrical mains as per voltage doubling circuit (Latour scheme), integrating capacitors from the groups of in-series connected thyristor and integrating capacitor are interconnected in-series and in parallel to the active load and a protective device while control electrodes of thyristors are connected to the thyristor control unit which inputs are connected to the three-phase electrical mains. The thyristor control unit contains a resistor voltage summator-divider, a comparator and two control circuits. The first circuit consists of in-series inverter, the first differentiating circuit, the first trigger pulse univibrator with power amplifier and the first output transformer while the second circuit consists of the in-series second differentiating circuit, the second trigger pulse univibrator with power amplifier and the second output transformer.

EFFECT: extension of application area.

3 cl, 4 dwg

FIELD: electricity.

SUBSTANCE: invention relates to electrical engineering. The device for controlling or stabilising single-phase or three-phase voltage includes an actuating element in form of two series-connected step-down and step-up transformers, and a control unit. One part of the core of the step-down transformer and one part of the core of the step-up transformer are in form of one part of a core which is common for both cores and is configured for mechanical displacement relative the remaining fixed part of the cores, wherein the maximum cross-section of the inserted part of the core of the step-down transformer matches the minimum cross-section of the inserted part of the core of the step-up transformer, and the minimum cross-section of the inserted part of the step-down transformer matches the maximum cross-section of the inserted part of the step-up transformer.

EFFECT: improved energy characteristics.

2 dwg

FIELD: electricity.

SUBSTANCE: in the method to supply to electrotechnical appliances with application of an AC voltage generator by means of voltage transfer from the generator to the low-voltage winding of a high-frequency transformer, electric energy to the low-voltage winding of the high-frequency transformer is sent via a unit from two high-frequency generators via a unit of capacitors serially connected with generators with a differences of frequencies Δ=f1-2, where f1 - frequency of the first generator, f2 - frequency of the second generator, f1. makes 1-100 kHz, and Δ=0.01-0.1f1, and a part of electric energy from the high-voltage winding is sent via a unit of the feedback voltage converter to generators supplying their low-voltage winding. In the device for supply of electrotechnical appliances comprising a source of AC voltage with a controlled frequency, a high-frequency transformer, the device comprises two high-frequency generators, outputs of which via capacitors are connected in series with the low-voltage winding of the high-frequency transformer and has an additional fifth capacitor, which is connected in parallel with the low-voltage winding, the high-voltage winding of the high-frequency transformer is connected with an electrotechnical appliance and via the voltage converter is connected with inputs of two high-frequency generators.

EFFECT: higher efficiency of the method and devices to supply to electrotechnical appliances and reduced losses when supplying to electrotechnical devices.

2 cl, 1 dwg

FIELD: electricity.

SUBSTANCE: grid-controlled inverter of single-phase alternating current includes transformer having primary winding connected to supply voltage source; secondary winding made in the form of three in-series connected sections with outputs from each of them, and four chains, each of which includes pair of in-series connected controlled valves parallel connected to each other and anode inverter buses. Extreme points of chains are connected by means of those buses to in-series connected smoothing coil, generator and ballast resistor, and middle points are connected to the appropriate outputs of sections of secondary transformer winding. In order to achieve the effect, non-controlled valve - diode, which is connected through cathode to anode bus, and through anode to cathode bus of inverter, is also introduced. Use of invention allows increasing power factor in nominal mode in all control zones from 0.7 to 0.84. Besides, average value of rectified voltage of inverter increases per each half-period in control zones 1, 2, 3, 4, and thus, electric energy flow of generator to mains increases by 15%.

EFFECT: improving power factor in nominal mode in control zones 2, 3, 4 owing to decreasing margin angle δ, which is specified by decrease of commutating angle of large circuit γ, at maintaining voltage regulation in those zones in wide range, and in the first zone due to decrease of margin angle δ, which is specified by decrease of commutating angle γ.

6 dwg

FIELD: electricity.

SUBSTANCE: form of consumed current may also differ from current consumed by load, which makes it possible to use the method not only for control of value and correction of AC voltage form, but also for correction of load capacity coefficient. Device to realise method of AC voltage control includes noise-suppression capacitor (C1), integrating throttle (L), commutator K for two positions, noise-suppression capacitors (C2, C3) and autotransformer with sectional winding (AT), besides, input voltage is sent to one output of integrating throttle and noise-suppression capacitor (C1), the second output of integrating throttle is connected to input of commutator (K), output (1) AT (winding start) is connected to common wire of device and point of connection of noise-suppression capacitors (C1-C3), output of section (2), which determines minimum input voltage, is connected to the first output of commutator (K) and the second output of noise-suppression capacitor (C2), output of section (3), which determines maximum input voltage, is connected to the second output of commutator (K) and the second output of noise-suppression capacitor (C3), and output voltage is taken from output (4) AT.

EFFECT: provides for smooth control in wide range of input voltage variation with the possibility to correct form of input voltage with device simplification.

3 cl, 5 dwg

FIELD: electricity.

SUBSTANCE: diagram transmits the amplified resonant power generated in winding of common transformer, when subsequent or parallel resonance of common electric power supply has been formed, to the load through common transformer. Diagram includes the following: electric power supply to generate and supply voltage or current; power amplifier to generate amplified resonant power by using voltage or current; and power transmission module to transmit the amplified resonant power to load by using the transformer.

EFFECT: improving the quantity of electric power supplied to the load.

4 cl, 15 dwg, 3 tbl

FIELD: electricity.

SUBSTANCE: invention may be used to control or stabilise voltage of power and converting transformers, in particular for supply of individual loads in networks with unstable parametres. It is proposed to control voltage alternately in zones of current and voltage match and non-match. Besides voltage should be reduced first in zones of current and voltage signs match by increasing switching angle and second in zones of current and voltage signs non-match by reducing switching angle, and pressure increase shall be executed in reverse order.

EFFECT: expanded range of control in case of active-inductive, active-capacitance and recuperative loads, and in idle running of transformer.

3 dwg

FIELD: electricity.

SUBSTANCE: improved efficiency of method implementation is achieved due to multi-phase system balancing against specified phase, or phase with load current close to mean current, or less loaded phase defined as reference phase. By the method, balancing is implemented by generation of pre-formed currents by means of additional power source in each of remaining (n-1) phases, so that in each balanced (n-1) phase of the main n-phase network, the geometrical sum of currents generated in balanced phase and with load current is equal modulo to current in reference phase, and angle formed by the current of reference phase and total current of balanced phase following the reference phase at forward sequence of phases, as well as between total currents of neighbouring (n-1) balanced phases is equal to electrical degrees.

EFFECT: improved efficiency of multi-phase system balancing due to increased response and simplified implementation, extended application sphere, improved economy.

1 dwg

Voltage regulator // 2346318

FIELD: electricity.

SUBSTANCE: voltage regulator model proposed is an invention referring to the sphere of electrical engineering. Device contains input and output terminals, a sensor of input main voltage and a transformer, the latter's primary coil connected to the first diagonal of a bridge circuit composed of four normally open adjustable alternating current switches; the transformer secondary coil is serially connected to the load circuit with an adjustable alternating current switch connected parallel to it. The control alternating current switches are controlled via three-position comparator units. There are time delay elements inserted in the "more" and "less" control output signals circuit of the three-position comparator unit that enable synchronisation of the transformer primary coil connection and secondary coil bridging with the upper and the lower voltage setup units connected to the "Higher Voltage" and the "Lower Voltage" outputs of the three-position comparator unit accordingly.

EFFECT: simplification of design combined with extension of functional capabilities, minimisation of weight and overall dimensions, rejection of noise generated by the device and maintenance of the consumer end voltage harmonicity under major supply voltage fluctuations.

1 dwg

The invention relates to a Converter equipment and can be used to increase the total allowable current thyristor Converter collected on the six-phase rectification circuit
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