CN102801160A - Dynamic trend controller based on voltage magnitude and phase angle control and control method thereof - Google Patents

Abstract

The invention relates to a dynamic trend controller based on voltage magnitude and phase angle control and a control method thereof. The dynamic trend controller comprises a controllable three-phase transformer, a first power unit, a second power unit, a measurement and control module, a series winding unit, an input voltage transformer, an output voltage transformer and an output current transformer, wherein a secondary winding of the controllable three-phase transformer comprises a man joint, a positive tap joint and a negative tap joint, and each phase respectively outputs 2 groups of independent windings with the transformation ratio of N, wherein N is greater than 0 and smaller than 0.2; and the series winding unit of each phase comprises another two phases of the controllable three-phase transformer and each 1 group of independent windings with opposite voltage polarities connected in series. In the invention, the decoupling control of active power and reactive power is realized, the dynamic regulation capability and the power transmission capacity of the power system trend are increased, the stability, the reliability and the like of the system are improved, and the dynamic trend controller has the characteristics of low cost, independent control of active power and reactive power and high reliability.

Description

Dynamic power flow controller and control method thereof based on voltage magnitude and phase angle control

Technical field

The present invention relates to the flexible transmission technical field, particularly a kind of dynamic power flow controller and control method thereof based on voltage magnitude and phase angle control.

Background technology

Along with the access of intermittent new forms of energy such as interconnected, the wind-powered electricity generation of large-scale power system and the use of various new equipments, make operation of power networks greatly increase in the possibility at stability limit edge.Therefore, the flexibility of operation of power networks, trend controllability and grid stability seem and become more and more important, and also are the targets that intelligent grid is pursued simultaneously.And in the complicated day by day electrical network of a structure, the voltage and current of control circuit will become key of problem simultaneously.

For the voltage and current of control circuit, conventional way is that the optimal load flow through off-line calculates and state estimation is adjusted the excitation of generator, and load tap changer and reactive power compensator satisfy the double constraints of voltage and current.But in the network of a complicacy, this is a very challenging problem, to such an extent as to have no controller can control a complex network in real time in practice.

Some new methods amplitude and the phase place of the node voltage of control circuit are simultaneously arranged, realize control active power and reactive power through control to node voltage phase place and amplitude.Can provide the device of such function that FACTS equipment is arranged, such as THE UPFC (united power flow control, UPFC) and SSSC (static synchronous series compensator, SSSC).Reactive power compensator such as SVC and STATCOM can be through idle support Control Node voltage magnitudes.Although the FACTS device has got into the shaping phase, the economy of said apparatus still has to be waited to check.Phase shifter can provide power flow control, but can not control voltage, and this control is slow.Solid-state transformer is called electric power electric transformer again, can control the amplitude and the phase angle of voltage, but needs to use a large amount of high-power electric and electronic switching devices, and research and development still rest on theoretical research stage.To above problem, the someone has proposed cheaply the controllable network transformer, and (controllable network transformer, CNT), its required electric power electronic switch capacity is the sub-fraction of transformer capacity.It can control output voltage amplitude and phase angle, but to the control range of voltage phase angle smaller and voltage magnitude control can not realize decoupling zero with phase angle, in addition in order to eliminate the low-frequency harmonics that this method produces, need the bigger cost of increase.

But also there is significant limitation in present FACTS technology: FACTS unit engineering cost is high, applies difficulty; There is ill-effect between FACTS device and power equipment and other controllers; The loss of FACTS device self is big; The complicated control structure of FACTS device and to the requirement of corresponding auxiliary devices such as communications facility has proposed more strict requirement to the operation and the control of electrical network; The additional problem that plant failure is brought; Stability of a system problem that the series connection access causes or the like makes its application in electrical network receive very big restriction.

Summary of the invention

To the problems referred to above; The dynamic power flow controller and the control method thereof that the purpose of this invention is to provide the controlled three-phase transformer of independently controlling based on voltage magnitude and phase angle; This dynamic power flow controller is based on the controlled three-phase transformer of full-control type power electronic switch; Through the independent control realization transmission line active power of controlled three-phase transformer output voltage phase angle and amplitude and the decoupling zero control of reactive power, have low cost, high reliability characteristics.

Technical solution of the present invention is following:

A kind of dynamic power flow controller based on voltage magnitude and phase angle control is characterized in that this dynamic power flow controller comprises: controlled three-phase transformer, first power cell, second power cell, measurement constitute with control module, the winding element of connecting, input voltage instrument transformer, output voltage instrument transformer and output current transformer:

The secondary of described controlled three-phase transformer comprise major joint, plus tapping head, minus tapping head,, and every phase independent winding that to export 2 groups of no-load voltage ratios separately be N, wherein 0 < N < 0.2;

The series connection winding element of every phase is formed by other two-phase and each opposite 1 group of independent winding serial connection of polarity of voltage of controlled three-phase transformer;

Described first power cell is made up of first switching power tube, second switch power tube, first filter inductance, first filter capacitor and second filter capacitor;

Described second power cell is made up of the 3rd switching power tube, the 3rd switching power tube, second filter inductance the 3rd filter capacitor and the 4th filter capacitor;

Described first switching power tube, second switch power tube, the 3rd switching power tube and the 4th switching power tube constitute by 2 insulated gate bipolar transistor differential concatenations;

The plus tapping head of the described controlled three-phase transformer secondary of one termination of described first switching power tube; One termination minus tapping head of described second switch power tube; The other end of the other end of this first group of switching power tube and second group of switching power tube links to each other and this tie point links to each other with an end of described first filter inductance; The other end of this first filter inductance links to each other with an end of described series connection winding element, an end of the 4th switching power tube, an end of second filter capacitor respectively; The other end of second filter capacitor links to each other with the secondary major joint of described controlled three-phase transformer; The other end of described series connection winding element links to each other with an end of the 3rd switching power tube; Described the 3rd switching power tube other end links to each other with the 4th switching power tube other end and this tie point links to each other with an end of described second filter inductance, and the other end of this second filter inductance connects out-put supply or load

Described first filter capacitor is connected between the plus tapping head and minus tapping head of described controlled three-phase transformer secondary; Described the 3rd filter capacitor is connected across between the 3rd switching power tube and the disjunct two ends of the 4th switching power tube; One end of described the 4th filter capacitor links to each other with the tie point of 2 serial connection windings in the series connection winding element; The other end of the 4th filter capacitor connects out-put supply or load end

One side of described input voltage instrument transformer links to each other with the former limit of controlled three-phase transformer input voltage main circuit, and voltage signal output end links to each other with the voltage signal input port of control module with described measurement;

Described output voltage instrument transformer, a side links to each other with controlled three-phase transformer secondary output voltage main circuit, and voltage signal output end links to each other with the voltage signal input port of control module with described measurement;

Described output current transformer is serially connected in the output main circuit of controlled three-phase transformer, and its current signal output end links to each other with the current signal input port of control module with described measurement;

Described measurement links to each other with the control end of the 4th switching power tube with the described first switching power tube second switch power tube, the 3rd switching power tube respectively with the control signal output ends of control module, and this measurement links to each other with host computer with control module.

Described measurement and control module are digital signal processor, single-chip microcomputer or computer.

Utilize described dynamic power flow controller to carry out the control method of output voltage amplitude, phase angle, its characteristics are that this method comprises following concrete steps:

1) establish the positive and negative tap no-load voltage ratio of controlled three-phase transformer and be respectively (1+N) and (1-N), controlled three-phase transformer three-phase input voltage is respectively:

V _ain=sin(ω ₀t)

V _bim=sin(ω ₀t+120°) (1)

V _cin=sin(ω ₀t-120°)

Wherein, V _AinBe A phase input voltage, V _BinBe B phase input voltage, V _CinBe C phase input voltage;

2) through pulse-width modulation the duty ratio of first switching power tube, second switch power tube, the 3rd switching power tube and the 4th switching power tube is regulated:

If the duty ratio of first switching power tube and second switch power tube is D ₁, the duty ratio of establishing the 3rd switching power tube and the 4th switching power tube is D ₂, wherein, 0≤D ₁≤1,0≤D ₂≤1;

Work as D ₁=1 o'clock, S ₁Conducting, S ₂Turn-off, work as D ₁=0 o'clock, S ₂Conducting, S ₁Turn-off; Work as D ₂=1 o'clock, S ₃Conducting, S ₄Turn-off, work as D ₂=0 o'clock, S ₄Conducting, S ₃Turn-off;

3) calculate A phase output voltage, formula is following:

V _aout=V _ain[(1+N)D ₁+(1-N)(1-D ₁)] (2)

+(NV _bin-NV _cin)D ₂

4) with V in the step 1) _Ain, V _Bin, V _CinSubstitution formula (2) obtains:

$V_{\mathrm{aout}}=[(1+N){\mathrm{<figure-callout\; id="1"\; label="D"\; filenames="HDA00002013109700012.png,HDA00002013109700041.png"\; state="\{\{state\}\}">D</figure-callout>}}_1+(1-N)(1-D_1)]\sin \left({\mathrm{\&omega;}}_{0}t\right)$ $\left(3\right)$

$+\sqrt{3}\mathrm{<figure-callout\; id="2"\; label="N\; D"\; filenames="HDA00002013109700012.png,HDA00002013109700032.png"\; state="\{\{state\}\}">N</figure-callout>}{D}_{}{}_2\cos \left({\mathrm{\&omega;}}_{0}t\right)$

5) output voltage amplitude is:

$A=\sqrt{{[(1+N)D_1+(1-N)(1-D_1)]}^2+{\left(\sqrt{3}N{D}_2\right)}^2}---\left(4\right)$

6) output voltage phase shift angle θ is:

$\mathrm{\&theta;}={\tan }^{-1}\left(\frac{\sqrt{3}N{D}_2}{[(1+N)D_1+(1-N)(1-D_1)]}\right)---\left(5\right)$

Through changing duty ratio D ₁And D ₂Can change output voltage amplitude and phase angle.Common N<0.2 therefore, amplitude is regulated and is depended primarily on D ₁, phase angle is regulated and is depended primarily on D ₂

When N=0.1, then approximate can getting, the voltage magnitude control range is:

0.9≤A≤1.1 (6)

The voltage phase angle control range is:

7) described dynamic power flow controller is serially connected between two electrical networks; Input termination first electrical network (11) of dynamic power flow controller; The output of this dynamic power flow controller is connected with second electrical network (21) through outlet line, transmits electricity to second electrical network (21) through this dynamic power flow controller and transmission line;

The transmission line reactance of 8) establishing between output of dynamic power flow controller and the electrical network 2 is J ω L;

9) then the relation of the active power P of dynamic power flow controller transmission and reactive power Q and dynamic power flow controller output voltage phase shift angle θ is following:

$P=\frac{V_{2}A{\mathrm{<figure-callout\; id="1"\; label="V"\; filenames="HDA00002013109700012.png,HDA00002013109700041.png"\; state="\{\{state\}\}">V</figure-callout>}}_1}{\mathrm{\&omega;L}}\sin (\mathrm{\&delta;}+\mathrm{\&theta;})---\left(8\right)$

$Q=\frac{{\mathrm{<figure-callout\; id="2"\; label="V"\; filenames="HDA00002013109700012.png,HDA00002013109700032.png"\; state="\{\{state\}\}">V</figure-callout>}}_2^2-V_{2}A{\mathrm{<figure-callout\; id="1"\; label="V"\; filenames="HDA00002013109700012.png,HDA00002013109700041.png"\; state="\{\{state\}\}">V</figure-callout>}}_1\cos (\mathrm{\&delta;}+\mathrm{\&theta;})}{\mathrm{\&omega;L}}---\left(9\right)$

V wherein ₁And V ₂Be respectively the voltage magnitude of first electrical network and second electrical network, δ is V ₂With V ₁Differential seat angle.

From formula (8), (9), can find out; Active power P is main relevant with controlled three-phase transformer output voltage θ; Reactive power Q is then main relevant with controlled three-phase transformer output voltage amplitude A, the main and duty ratio D of the active power P of promptly controlled three-phase transformer output ₂Relevant, the then main and duty ratio D of reactive power Q ₁Relevant;

Therefore, through to duty ratio D ₁, D ₂Adjusting realized the adjusting of dynamic power flow controller active power of output and reactive power.Because the tap conducting of controlled three-phase transformer is controlled, control switch power tube IGBT capacity is merely the part of controlled three-phase transformer capacity, thereby cost is low, thus the control of the dynamic power flow of the low cost of realization, high reliability.

Compared with prior art, characteristics of the present invention are following:

1. switching power tube only needs the conducting of controlled three-phase transformer tap is controlled, thereby cost is low, has overcome the expensive problem of existing FACTS device;

2. realize the decoupling zero control of transmission line active power and reactive power through the independent control of dynamic power flow controller output voltage phase angle and amplitude;

3. output voltage does not contain low-order harmonic, quality is good.

Description of drawings

Fig. 1 is that the dynamic power flow controller that the present invention is based on voltage magnitude and phase angle control is serially connected in 2 connection layouts in the electrical network.

Fig. 2 is the structural representation that the present invention is based on the dynamic power flow controller of voltage magnitude and phase angle control.

Fig. 3 is the voltage vector sketch map that the present invention changes the voltage phase angle principle, and wherein a has showed how to obtain the component of voltage perpendicular with A by B, C two phase voltages; B is the output voltage vector adjustable range as shown in the frame of broken lines among the figure.

Fig. 4 is that harmonic wave of output voltage of the present invention is analyzed sketch map.Ordinate Mag is a voltage magnitude among the figure, and abscissa Frequency is a frequency.

Fig. 5 is the present invention's electronic power switch device voltage and current waveform analogous diagram when working, and IGBT is an insulated gate transistor among the figure, and Diode is the inverse parallel diode of IGBT.

Fig. 6 is an input and output voltage waveform sketch map of the present invention.

Fig. 7 is a Reactive Power Control emulation sketch map of the present invention, and Q is a reactive power among the figure.

Fig. 8 is an active power control emulation sketch map of the present invention, and P is an active power among the figure.

Embodiment

Below in conjunction with embodiment and accompanying drawing the present invention is described further, but should limit protection scope of the present invention with this.

See also Fig. 2 earlier; Fig. 2 is the structural representation of dynamic power flow controller of the present invention; As shown in the figure; The controlled three-phase transformer device that a kind of voltage magnitude and phase angle are independently controlled comprises: controlled three-phase transformer 1, first power cell 2, second power cell 8, measurement and control module 3, the winding element 4 of connecting, input voltage instrument transformer 5, output voltage instrument transformer 6 and output current transformer 7 constitute:

The secondary of described controlled three-phase transformer 1 comprises major joint 12, plus tapping head 13, minus tapping head 11, and every phase independent winding that to export 2 groups of no-load voltage ratios separately be N, and wherein 0 < N < 0.2;

The series connection winding element 4 of every phase is formed by other two-phase and each opposite 1 group of independent winding serial connection of polarity of voltage of controlled three-phase transformer 1;

Described first power cell 2 is by the first switching power tube S ₁, second switch power tube S ₂, the first filter inductance L _F1The first filter capacitor C _F1With the second filter capacitor C _fForm;

Described second power cell 8 is by the 3rd switching power tube S ₃, the 3rd switching power tube S ₄, the second filter inductance L _F2The 3rd filter capacitor C _F3With the 4th filter capacitor C _F4Form;

The described first switching power tube S ₁, second switch power tube S ₂, the 3rd switching power tube S ₃With the 4th switching power tube S ₄Constitute (not shown) by 2 insulated gate bipolar transistor differential concatenations;

The described first switching power tube S ₁The plus tapping head 13 of described controlled three-phase transformer 1 secondary of a termination, described second switch power tube S ₂A termination minus tapping head 11, this first group of switching power tube S ₁The other end and second group of switching power tube S ₂The other end link to each other and this tie point and the described first filter inductance L _F1An end link to each other this first filter inductance L _F2The other end respectively with an end, the 4th switching power tube S of the described winding element 4 of connecting ₄An end, the second filter capacitor C _F2An end link to each other the second filter capacitor C _F2The other end link to each other the other end of described series connection winding element 4 and the 3rd switching power tube S with the secondary major joint 12 of described controlled three-phase transformer 1 ₃An end link to each other described the 3rd switching power tube S ₃The other end and the 4th switching power tube S ₄The other end links to each other and this tie point and the described second filter inductance L _F2An end link to each other this second filter inductance L _F2The other end connect out-put supply or load,

The described first filter capacitor C _F1Be connected between the plus tapping head 13 and minus tapping head 11 of described controlled three-phase transformer 1 secondary described the 3rd filter capacitor C _F3Be connected across the 3rd switching power tube S ₃With the 4th switching power tube S ₄Between the disjunct two ends, described the 4th filter capacitor C _F4An end with the series connection winding element 4 in 2 the serial connection windings tie points link to each other the 4th filter capacitor C _F4The other end connect out-put supply or load end,

One side of described input voltage instrument transformer 5 links to each other with the former limit of controlled three-phase transformer input voltage main circuit, and voltage signal output end links to each other with the voltage signal input port of control module 3 with described measurement;

Described output voltage instrument transformer 6, one sides link to each other with controlled three-phase transformer secondary output voltage main circuit, and voltage signal output end links to each other with the voltage signal input port of control module 3 with described measurement;

Described output current transformer 7 is serially connected in the output main circuit of controlled three-phase transformer, and its current signal output end links to each other with the current signal input port of control module 3 with described measurement;

The control signal output ends of described measurement and control module 3 respectively with the described first switching power tube S ₁Second switch power tube S ₂, the 3rd switching power tube S ₃With the 4th switching power tube S ₄Control end link to each other, this measurement links to each other with host computer with control module 3.

Described measurement and control module 3 are digital signal processor, single-chip microcomputer or computer.

Utilize the dynamic power flow controller to carry out the control method of output voltage amplitude, phase angle, it is characterized in that this method comprises following concrete steps:

1) establish the positive and negative tap no-load voltage ratio of controlled three-phase transformer and be respectively (1+N) and (1-N), the three-phase input voltage of establishing controlled three-phase transformer is respectively:

V _ain=sin(ω ₀t)

V _bin=sin(ω ₀t+120°) (1)

V _cin=sin(ω ₀t-120°)

2) pass through the PWM technology to switch S ₁, S ₂And S ₃, S ₄Duty ratio regulate.If S ₁, S ₂Duty ratio be D ₁, establish S ₃, S ₄Duty ratio be D ₂, 0≤D ₁≤1,0≤D ₂≤1.Work as D ₁=1 o'clock, S ₁Conducting, S ₂Turn-off, work as D ₁=0 o'clock, S ₂Conducting, S ₁Turn-off; Work as D ₂=1 o'clock, S ₃Conducting, S ₄Turn-off, work as D ₂=0 o'clock, S ₄Conducting, S ₃Turn-off.

3) can get A phase output voltage is:

V _aout=V _ain[(1+N)D ₁+(1-N)(1-D ₁)] (2)

+(NV _bin-NV _cin)D ₂

4) with V _Ain, V _Bin, V _CinSubstitution gets:

$V_{\mathrm{aout}}=[(1+N){\mathrm{<figure-callout\; id="1"\; label="D"\; filenames="HDA00002013109700012.png,HDA00002013109700041.png"\; state="\{\{state\}\}">D</figure-callout>}}_1+(1-N)(1-D_1)]\sin \left({\mathrm{\&omega;}}_{0}t\right)$ $\left(3\right)$

$+\sqrt{3}\mathrm{<figure-callout\; id="2"\; label="N\; D"\; filenames="HDA00002013109700012.png,HDA00002013109700032.png"\; state="\{\{state\}\}">N</figure-callout>}{D}_{}{}_2\cos \left({\mathrm{\&omega;}}_{0}t\right)$

Can find out that from following formula output voltage is except containing the sinusoidal component consistent with input phase, also contain and its cosine component of phasic difference 90 degree mutually.

5) output voltage amplitude is:

$A=\sqrt{{[(1+N){\mathrm{<figure-callout\; id="1"\; label="D"\; filenames="HDA00002013109700012.png,HDA00002013109700041.png"\; state="\{\{state\}\}">D</figure-callout>}}_1+(1-N)(1-D_1)]}^2+{\left(\sqrt{3}N{D}_2\right)}^2}---\left(4\right)$

6) output voltage phase shift angle θ is:

$\mathrm{\&theta;}={\tan }^{-1}\left(\frac{\sqrt{3}N{D}_2}{[(1+N){\mathrm{<figure-callout\; id="1"\; label="D"\; filenames="HDA00002013109700012.png,HDA00002013109700041.png"\; state="\{\{state\}\}">D</figure-callout>}}_1+(1-N)(1-D_1)]}\right)---\left(5\right)$

When N=0.1, then approximate can getting, the voltage magnitude control range is:

0.9≤A≤1.1 (6)

The voltage phase angle control range is:

Through changing duty ratio D ₁And D ₂Can change output voltage amplitude and phase angle.Common N<0.2 therefore, amplitude is regulated and is depended primarily on D ₁, phase angle is regulated and is depended primarily on D ₂

7) described dynamic power flow controller is serially connected between two electrical networks; Input termination first electrical network (11) of dynamic power flow controller; The output of this dynamic power flow controller is connected with second electrical network 21 through outlet line, transmits electricity to second electrical network 22 through this dynamic power flow controller and transmission line;

The transmission line reactance of 8) establishing between the output of dynamic power flow controller and second electrical network 22 is j ω L;

9) then the relation of the active power P of dynamic power flow controller transmission and reactive power Q and dynamic power flow controller output voltage phase shift angle θ is following:

$P=\frac{V_{2}A{\mathrm{<figure-callout\; id="1"\; label="V"\; filenames="HDA00002013109700012.png,HDA00002013109700041.png"\; state="\{\{state\}\}">V</figure-callout>}}_1}{\mathrm{\&omega;L}}\sin (\mathrm{\&delta;}+\mathrm{\&theta;})---\left(8\right)$

$Q=\frac{{\mathrm{<figure-callout\; id="2"\; label="V"\; filenames="HDA00002013109700012.png,HDA00002013109700032.png"\; state="\{\{state\}\}">V</figure-callout>}}_2^2-V_{2}A{\mathrm{<figure-callout\; id="1"\; label="V"\; filenames="HDA00002013109700012.png,HDA00002013109700041.png"\; state="\{\{state\}\}">V</figure-callout>}}_1\cos (\mathrm{\&delta;}+\mathrm{\&theta;})}{\mathrm{\&omega;L}}---\left(9\right)$

V wherein ₁And V ₂Be respectively the voltage magnitude of first electrical network and second electrical network, δ is V ₂With V ₁Differential seat angle.

From formula (8), (9), can find out; Active power P is main relevant with controlled three-phase transformer output voltage θ; Reactive power Q is then main relevant with controlled three-phase transformer output voltage amplitude A, the main and duty ratio D of the active power P of promptly controlled three-phase transformer output ₂Relevant, the then main and duty ratio D of reactive power Q ₁Relevant;

Therefore, through to duty ratio D ₁, D ₂Adjusting realized the adjusting of dynamic power flow controller active power of output and reactive power.Because the tap conducting of controlled three-phase transformer is controlled, control switch power tube IGBT capacity is merely the part of controlled three-phase transformer capacity, thereby cost is low, thus the control of the dynamic power flow of the low cost of realization, high reliability.

Fig. 3 is phase shift of dynamic power flow controller output voltage and the voltage vector diagram that changes the amplitude principle.Fig. 4 is that harmonic wave of output voltage of the present invention is analyzed sketch map, can find out that output voltage does not contain low-order harmonic; Only contain the switching frequency harmonic wave; Therefore, filtering easily is because first and second group power cell all contains high-frequency filter circuit; To high-frequency harmonic filtering in addition, thereby make the waveform of voltage of controlled three-phase transformer outputting high quality.

Fig. 5 is N=0.1, D ₁=0.5, D ₂=0 o'clock controlled three-phase transformer electronic power switch device voltage analogous diagram shows among the figure that electronic power switch device operating voltage is the sub-fraction of controlled three-phase transformer, i.e. 20% (2N doubly).From analogous diagram 6 found out phase shift about 11 the degree, output amplitude has increased by 10%, and is consistent with above-mentioned analysis result.

Dynamic power flow control emulation is following:

The used model of emulation is as shown in Figure 3, and V1 and V2 amplitude all are 35kV, V ₁Compare V ₂Leading 20 °.

Keep D ₂=0, D ₁Increase by 0.25 from 0 per step and change to 1, the reactive power that circuit transmits changes as shown in Figure 7.

Keep D ₁=0.5, D ₂Increase by 0.25 from 0 per step and change to 1, the active power that circuit transmits changes as shown in Figure 8.

From above-mentioned simulation result, can know, change modulation parameter D ₁, D ₂, can control active power and reactive power that the dynamic power flow controller is exported dynamically.

Claims (3)

1. dynamic power flow controller and control method thereof based on the control of voltage magnitude and phase angle; It is characterized in that this dynamic power flow controller comprises: controlled three-phase transformer (1), first power cell (2), second power cell (8), measurement constitute with control module (3), the winding element of connecting (4), input voltage instrument transformer (5), output voltage instrument transformer (6) and output current transformer (7):

The secondary of described controlled three-phase transformer (1) comprises major joint (12), plus tapping head (13), minus tapping head (11), and every phase independent winding that to export 2 groups of no-load voltage ratios separately be N, and wherein 0 < N < 0.2;

The series connection winding element (4) of every phase is formed by other two phases and each opposite 1 group of independent winding serial connection of polarity of voltage of controlled three-phase transformer (1);

Described first power cell (2) is by the first switching power tube (S ₁), second switch power tube (S ₂), the first filter inductance (L _F1) the first filter capacitor (C _F1) and the second filter capacitor (C _F2) form;

Described second power cell (8) is by the 3rd switching power tube (S ₃), the 3rd switching power tube (S ₄), the second filter inductance (L _F2) the 3rd filter capacitor (C _F3) and the 4th filter capacitor (C _F4) form;

The described first switching power tube (S ₁), second switch power tube (S ₂), the 3rd switching power tube (S ₃) and the 4th switching power tube (S ₄) constitute by 2 insulated gate bipolar transistor differential concatenations;

The described first switching power tube (S ₁) the plus tapping head (13) of the described controlled three-phase transformer of a termination (1) secondary, described second switch power tube (S ₂) a termination minus tapping head (11), this first group of switching power tube (S ₁) the other end and second group of switching power tube (S ₂) the other end link to each other and this tie point and the described first filter inductance (L _F1) an end link to each other this first filter inductance (L _F1) the other end respectively with an end, the 4th switching power tube (S of the described winding element of connecting (4) ₄) an end, the second filter capacitor (C _F2) an end link to each other the second filter capacitor (C _F2) the other end link to each other the other end of described series connection winding element (4) and the 3rd switching power tube (S with the secondary major joint (12) of described controlled three-phase transformer (1) ₃) an end link to each other described the 3rd switching power tube (S ₃) other end and the 4th switching power tube (S ₄) other end continuous and this tie point and the described second filter inductance (L _F2) an end link to each other this second filter inductance (L _F2) the other end connect out-put supply or load,

The described first filter capacitor (C _F1) be connected between the plus tapping head (13) and minus tapping head (11) of described controlled three-phase transformer (1) secondary described the 3rd filter capacitor (C _F3) be connected across the 3rd switching power tube (S ₃) and the 4th switching power tube (S ₄) between the disjunct two ends, described the 4th filter capacitor (C _F4) an end and series connection winding element (4) in the tie points of 2 serial connection windings link to each other the 4th filter capacitor (C _F4) the other end connect out-put supply or load end,

One side of described input voltage instrument transformer (5) links to each other with the former limit of controlled three-phase transformer input voltage main circuit, and voltage signal output end links to each other with the voltage signal input port of described measurement with control module (3);

Described output voltage instrument transformer (6), a side links to each other with controlled three-phase transformer secondary output voltage main circuit, and voltage signal output end links to each other with the voltage signal input port of described measurement with control module (3);

Described output current transformer (7) is serially connected in the output main circuit of controlled three-phase transformer, and its current signal output end links to each other with the current signal input port of described measurement with control module (3);

The control signal output ends of described measurement and control module (3) respectively with the described first switching power tube (S ₁) second switch power tube (S ₂), the 3rd switching power tube (S ₃) and the 4th switching power tube (S ₄) control end link to each other, this measurement links to each other with host computer with control module (3).

2. dynamic power flow controller according to claim 1 is characterized in that described measurement and control module (3) are digital signal processor, single-chip microcomputer or computer.

3. utilize the described dynamic power flow controller of claim 1 to carry out the control method of output voltage amplitude and phase angle, it is characterized in that this method comprises following concrete steps:

1) establish the positive and negative tap no-load voltage ratio of controlled three-phase transformer and be respectively (1+N) and (1-N), controlled three-phase transformer three-phase input voltage is respectively:

V _ain=sin(ω ₀t)

V _bin=sin(ω ₀t+120°) (1)

V _cin=sin(ω ₀t-120°)

Wherein, V _AinBe A phase input voltage, V _BinBe B phase input voltage, V _CinBe C phase input voltage;

2) through pulse-width modulation the duty ratio of first switching power tube, second switch power tube, the 3rd switching power tube and the 4th switching power tube is regulated:

If the duty ratio of first switching power tube and second switch power tube is D ₁, the duty ratio of establishing the 3rd switching power tube and the 4th switching power tube is D ₂, wherein, 0≤D ₁≤1,0≤D ₂≤1;

3) calculate A phase output voltage, formula is following:

V _aout=V _ain[(1+N)D ₁+(1-N)(1-D ₁)] (2)

+(NV _bin-NV _cin)D ₂

4) with V in the step 1) _Ain, V _Bin, V _CinSubstitution formula (2) obtains:

$V_{\mathrm{aout}}=[(1+N)D_1+(1-N)(1-D_1)]\sin \left({\mathrm{\&omega;}}_{0}t\right)$ $\left(3\right)$

$+\sqrt{3}N{D}_2\cos \left({\mathrm{\&omega;}}_{0}t\right)$

5) output voltage amplitude is:

$A=\sqrt{{[(1+N)D_1+(1-N)(1-D_1)]}^2+{\left(\sqrt{3}N{D}_2\right)}^2}---\left(4\right)$

6) output voltage phase shift angle θ is:

$\mathrm{\&theta;}={\tan }^{-1}\left(\frac{\sqrt{3}N{D}_2}{[(1+N)D_1+(1-N)(1-D_1)]}\right)---\left(5\right)$

7) described dynamic power flow controller is serially connected between two electrical networks; Input termination first electrical network (11) of dynamic power flow controller; The output of this dynamic power flow controller is connected with second electrical network (21) through outlet line, transmits electricity to second electrical network (22) through this dynamic power flow controller and transmission line;

The output and the transmission line reactance between second electrical network of 8) establishing the dynamic power flow controller are j ω L;

9) then the relation of the active power P of dynamic power flow controller transmission and reactive power Q and dynamic power flow controller output voltage phase shift angle θ is following:

$P=\frac{V_{2}A{V}_1}{\mathrm{\&omega;L}}\sin (\mathrm{\&delta;}+\mathrm{\&theta;})---\left(8\right)$

$Q=\frac{V_2^2-V_{2}A{V}_1\cos (\mathrm{\&delta;}+\mathrm{\&theta;})}{\mathrm{\&omega;L}}---\left(9\right)$

V wherein ₁And V ₂Be respectively the voltage magnitude of first electrical network and second electrical network, δ is V ₂With V ₁Differential seat angle.

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