CN104578089B - Static reacance generator control method based on IGCT - Google Patents

Abstract

Static reacance generator control method of the present invention based on IGCT belongs to power electronics static reacance generator technology, purpose is high-performance SVG of the research and development based on IGCT, promote development and the practical application of SVG, it is characterized in that using the pulse converter of IGCT 12, by particular transform rule two three-phase unsteady flow bridges are carried out with the control strategy of asymmetrical current, the electric current for making phase-shifting transformer outlet side is sine-wave current, Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge are controlled by particular transform rule, IGCT is set to be used as full control switch, the full control of IGCT makes Trigger Angle phase shift range be changed into 180 °~180 °, realize active reactive four quadrant running.The IGCT static reacance generator built with the static reacance generator control method based on IGCT can be widely used in direct current transmission and distribution, exchange power transmission and distribution, alternating current-direct current electric arc furnaces and various smelting furnaces, the dynamic passive compensation of refining furnace.

Description

Static reacance generator control method based on IGCT

Technical field

The invention belongs to power electronics static reacance generator technology.

Background technology

Compared with static passive compensation device (SVC), due to static reacance generator (SVG) have small volume, it is lightweight, Governing speed is fast, range of operation is wide, the low advantage of harmonic content, since the eighties are put into commercial operation, has been obtained from last century Rapid application and development.But then, because the control system and control method of SVG are more complicated than SVC, major loop derailing switch Part need to use wholly-controled device, and number of devices is more, capacity big, so SVC of its price still than use IGCT is much higher, valency The inferior position of lattice also constrains the process of SVG development.

The initial stage of SVG applications, once in the period of very short in used IGCT as main switching device, but with electric power After the wholly-controled devices such as the development of electronic device, gate pole shut-off (GTO) IGCT occur, SVG employs full control without any exception Therefore type device obtains more preferable control performance as main switching device.Hereafter, SVG into wholly-controled device one All over the world, the research about the SVG based on IGCT in the last thirty years has disappeared in technical press system.

Because IGCT has the advantages that withstanding voltage is high, specified conducting electric current is big, efficiency high, good reliability, asked from it Just obtained a wide range of applications always since generation, although its range of application is limited due to the characteristic that there is half control, but it is real Border shows that IGCT is still have one of power electronic devices of suitable attraction at present, it is carried out deep using result Application study has important practical significance.If can use IGCT as main switching device in SVG, IGCT capacity is played Greatly, the advantage that high pressure, good stability, topological structure are simple and composite price is low, then the reality that will greatly promote SVG should With.

The content of the invention

Research object of the invention is the SVG systems based on IGCT.

The purpose of the present invention is further investigation SVG system changeovers mechanism, topological structure and control technology, and research and development are based on brilliant lock The high-performance SVG of pipe, promotes development and the practical application of SVG.

The method is characterized in that four quadrant running, harmonic wave in the active reactive of the static reacance generator based on IGCT Suppress and improve overall efficiency aspect and achieve breakthrough progress.

Static reacance generator control method of the present invention based on IGCT is characterized in by a direct current Storage Unit [1], level DC current control more than and allocation unit [2], two identical 6 pulse wave Thyristor Three-phase unsteady flow bridges [3] and [4], the phase-shifting transformer composition that the Y windings [5] and Δ winding [6] of a Y winding [7] and two 30 degree of mutual deviations are constituted, Using the control strategy of asymmetrical current, to two three-phase unsteady flows bridge [3] and [4] respectively by (1) formula and the particular transform of (2) formula Rule is controlled, and generation is mutually asymmetric, and Y windings [34] electric current and Δ winding [35] electric current that phase is also differed, and makes The electric current of phase-shifting transformer outlet side Y shape winding [36] is sine-wave current, effectively inhibits harmonic wave, by (1) formula and (2) formula Particular transform rule control Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge, result in Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge The electric current of switching device is constituting opening for Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge by the triangular current rule change of setting When closing device for IGCT, gate circuit transistor gate trigger signal is given when triangular current starts, IGCT is open-minded, in triangular wave electricity Stream is during zero, and thyristor current flows are zero to be forced to shut-off, and a combination of both makes IGCT to be used as full control switch, brilliant The full control of brake tube makes Trigger Angle phase shift range be changed into -180 °~180 °, realizes active reactive four quadrant running.

In formula：

I_BY：Y bridge DC currents

I_BΔ：Δ bridge DC current

I_dc：Direct current Storage Unit electric current

K=1,2 ...

Brief description of the drawings

Accompanying drawing 1 is the static reacance generator control method topology diagram based on IGCT, and 1 is direct current accumulation of energy in Fig. 1 Unit, the direct current energy storage equipment, according to practical situations, is respectively capacitor, battery, all types of direct current accumulators, each Plant active rectification device；2 is many level DC current controls and allocation unit；3 is Y winding Thyristor Three-phase unsteady flow bridges；4 is Δ Winding Thyristor Three-phase unsteady flow bridge；5 is phase-shifting transformer input side Y shape winding；6 is phase-shifting transformer input side Δ shape winding；7 It is phase-shifting transformer output side winding, Y connection.

Accompanying drawing 2 is oscillogram of the static reacance generator control method based on IGCT under ideal transformation, 21 in Fig. 2 It is direct current Storage Unit electric current I_dcWaveform；22 is Y winding three-phase unsteady flow bridge input currents I_BYWaveform；23 is that Δ winding three-phase becomes Stream bridge input current I_BΔWaveform；24 is phase-shifting transformer input side Y shape winding A phases I_aYCurrent waveform, B phases I_bYCurrent waveform and C Phase I_cYCurrent waveform and A phases I_aYCurrent waveform is similar to, and difference is only to differ 120 ° and 240 ° with A phases respectively；25 is phase shift transformation Device input side Δ shape winding A phases I_aΔCurrent waveform, B phases I_bΔCurrent waveform and C phases I_cΔCurrent waveform and A phases I_aΔCurrent waveform Similar, difference is only to differ 120 ° and 240 ° with A phases respectively；26 is phase-shifting transformer output, i.e. net side A phases I_ACurrent waveform, B Phase I_BCurrent waveform and C phases I_CCurrent waveform and A phases I_ACurrent waveform be similar to, difference be only differed with A phases respectively 120 ° and 240°。

Accompanying drawing 3 is the static reacance generator control method based on IGCT in incremental steps shape triangular waves such as uses Oscillogram, 31 is direct current Storage Unit electric current I in Fig. 3_dcWaveform；32 is Y winding three-phase unsteady flow bridge input currents I_BYWaveform；33 It is Δ winding three-phase unsteady flow bridge input current I_BΔWaveform；34 is phase-shifting transformer input side Y shape winding A phases I_aYCurrent waveform, B Phase I_bYCurrent waveform and C phases I_cYCurrent waveform and A phases I_aYCurrent waveform be similar to, difference be only differed with A phases respectively 120 ° and 240°；35 is phase-shifting transformer input side Δ shape winding A phases I_aΔCurrent waveform, B phases I_bΔCurrent waveform and C phases I_cΔCurrent waveform With A phases I_aΔCurrent waveform is similar to, and difference is only to differ 120 ° and 240 ° with A phases respectively；36 is phase-shifting transformer output, i.e. net Side A phases I_ACurrent waveform, B phases I_BCurrent waveform and C phases I_CCurrent waveform and A phases I_ACurrent waveform be similar to, difference be only respectively with A phases differ 120 ° and 240 °.

Accompanying drawing 4 is ripple of the static reacance generator control method based on IGCT in 60 ° of converter current lagging voltage Shape figure, 41 is current waveform in Fig. 4, and 42 is voltage waveform.

Accompanying drawing 5 is ripple of the static reacance generator control method based on IGCT in 60 ° of converter current leading voltage Shape figure, 51 is current waveform in Fig. 5, and 52 is voltage waveform.

Specific embodiment

Static reacance generator control method based on IGCT is using complete by a three winding phase-shifting transformer and two Typical 12 pulse converter of exactly the same Thyristor Three-phase unsteady flow bridge composition, the advantage of this Structural Transformation device is its phase shift Transformer winding structure is simple, and outlet is easy, and winding utilization is high, there is certain inhibitory action to harmonic wave；But from custom Eye see that this converter does not possess the ability of the continuous regulation and control active reactive of dynamic, is generally only using wholly-controled device When just possess regulation and control active reactive ability, this has turned into the obstacle for being technically difficult to go beyond for a long time；The present invention is exactly Fruitful innovative research and development have been carried out in this respect.

For the sake of for convenience of description, specific embodiment runs on inverter mode by the pulse converter of elaboration IGCT 12, i.e., Active state is exported corresponding to static reacance generator to illustrate.

The present invention using asymmetric many level synthesis control technologies, by the particular transform rule of (1) formula and (2) formula by direct current Storage Unit [1] electric current distributes to two three-phase unsteady flow bridges, and I_BY(ω t) and I_BΔ(ω t) and Y three-phase unsteady flows bridge [3] and Δ The ac output current synchronization of three-phase unsteady flow bridge [4], then Y three-phases unsteady flow bridge and the ac output current of Δ three-phase unsteady flow bridge are in non- Symmetrical waveform, and waveform and phase also differ, respectively waveform [24] and [25], but two synthesis of three-phase unsteady flow bridge The electric current [26] of alternating current, i.e. phase-shifting transformer outlet side is the sine-wave current without harmonic wave.

The commutation situation of switching device in three-phase unsteady flow bridge is further analyzed, Y three-phase unsteady flows are applied to by triangular current Bridge and Δ three-phase unsteady flow bridge, result in the electric current of switching device in Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge by the triangle of setting Ripple electric current rule changes, and when the switching device for constituting Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge is IGCT, applies triangular wave Gate circuit transistor gate trigger signal is given when electric current starts, IGCT is open-minded, during triangular current is zero, thyristor current flows are zero Shut-off is forced to, i.e., IGCT is opened and controlled by gate pole, and IGCT is voluntarily turned off when triangular current is zero, and a combination of both makes IGCT can be used as full control switch, and the full control of IGCT makes Trigger Angle phase shift range expand to -180 °~180 °, tool For active reactive four quadrant running condition.

Actually realize the waveform of triangular wave, can with etc. incremental steps shape triangular wave it is approximate, etc. incremental steps shape triangular wave Current waveform uses following principles, is realized by many level DC current controls and allocation unit [2]：

(1) direct current Storage Unit electric current equalization is assigned as m branch road, each branch road is connected to two gate-controlled switches, two Individual gate-controlled switch complimentary action, constitutes complementary switch pair, is connected respectively to Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge.

(2) complementary switch pair is switched every 30 °/m, making the electric current of inflow Y three-phase unsteady flow bridges increases a branch road amount, The electric current of inflow Δ three-phase unsteady flow bridge is also set to reduce by a branch road amount simultaneously, it is interval by m 30 °/m, when all branch currents After all flowing into Y three-phase unsteady flow bridges, then the electric current of inflow Y three-phase unsteady flow bridges is set to reduce by a branch road amount every 30 °/m, while also making The electric current for flowing into Δ three-phase unsteady flow bridge increases a branch road amount, until the electric current for flowing into Y three-phase unsteady flow bridges is reduced to zero, repeat with Upper process, it is possible to by direct current Storage Unit electric current by etc. incremental steps shape triangular wave rule distribute to Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge.

Using etc. incremental steps shape triangular wave when oscillogram be specific implementation oscillogram of the invention, [31] are that direct current stores Can cell current I_dcWaveform；[32] it is Y winding three-phase unsteady flow bridge input currents I_BYWaveform；[33] it is Δ winding three-phase unsteady flow bridge Input current I_BΔWaveform；[34] it is phase-shifting transformer input side Y shape winding A phases I_aYCurrent waveform；[35] it is defeated phase-shifting transformer Enter side Δ shape winding A phases I_aΔCurrent waveform；[36] it is phase-shifting transformer output A phases I_ACurrent waveform, is the ripple close to sine wave Shape, only contains a small amount of harmonic wave.

The pulse converter of IGCT 12 for describing above is operate in inverter mode, i.e., defeated corresponding to static reacance generator Go out active state, directly controlled by the initial phase of the increment triangular waves such as change and to its current amplitude, can make The pulse converter of IGCT 12 is separately operable in rectification state, i.e., be input into active state, nothing corresponding to static reacance generator The advanced running status of work(, i.e., export or input advanced idle state, idle delayed operation shape corresponding to static reacance generator State, i.e., corresponding to static reacance generator output or the idle state of Input Hysteresis.

Fig. 4 is that the static reacance generator control method based on IGCT occurs delayed idle oscillogram, in figure [41] Delayed 60 ° of [42] alternating voltage of converter alternating current.

Fig. 5 is that the static reacance generator control method based on IGCT occurs advanced idle oscillogram, in figure [51] Advanced 60 ° of [52] alternating voltage of converter alternating current.

Using the static reacance generator control based on IGCT of above-mentioned principle and direct current Storage Unit current distribution method Method processed has following characteristics：

Ac output current harmonic content increases and reduces with m, and the relation of converter output alternating current THD and m is shown in Table 1.

The relation table of table 1.THD and m

m	2	3	4	5	6	7	8	9
									THD	7.77%	5.25%	3.99%	3.28%	2.77%	2.45%	2.20%	2.02%

According to table 1, when m >=6, harmonic value is limited in the range of ＜ 3%, using this control method by tradition 12 The harmonic content control of the ＞ 8% of pulse converter is in the range of the harmonic content that controllable, satisfaction is actually needed.

Active reactive advanced, delayed can be continuously adjusted, and realize four quadrant running, zero it is active to specified real power control when Between≤5ms, specified advanced, delayed idle conversion time≤5ms.

Interior on a large scale direct current Storage Unit input and output voltage and electric current can be continuously adjusted, when output or suction When receiving idle, it is operated under 0 or low current state；When exporting or absorbing active, corresponding input and output electric current shape is operated in Under state.

It is in zero interval, to make Y three-phase unsteady flow bridges in the electric current of inflow Y three-phase unsteady flow bridges with Sofe Switch theory IGCT commutation, in the interval that the electric current of inflow Δ three-phase unsteady flow bridge is zero, makes the IGCT commutation of Δ three-phase unsteady flow bridge, Y tri- The IGCT of phase unsteady flow bridge and Δ three-phase unsteady flow bridge completes commutation under conditions of being zero in electric current, and IGCT is closed when electric current is zero It is disconnected, start when voltage is zero open-minded, without switching loss, IGCT working frequency 50Hz, switching frequency is low, thus overall efficiency It is high.

Compared with prior art, the static reacance generator control method based on IGCT realizes the full control of IGCT Change, the advantages of IGCT high pressure, current capacity are big, device performance is stable, system realizes simple, cheap can be played The static reacance generator of brand-new type is built, especially advantage is had more in high power static reacance generator application aspect.Additionally, by In asymmetric many level synthesis control technologies are employed, the harmonic wave suppression of more perfect static reacance generator itself is realized System；Due to the realization of Sofe Switch theory, the overall efficiency of system is had been further upgraded, while also for the reliability of system is done Favorable attributes are gone out.

The IGCT static reacance generator built with the static reacance generator control method based on IGCT can be extensive Be applied to direct current transmission and distribution, exchange power transmission and distribution, alternating current-direct current electric arc furnaces and various smelting furnaces, the dynamic passive compensation of refining furnace.

Claims (4)

1. a kind of static reacance generator control method based on IGCT is characterized in by a direct current Storage Unit [1], one Individual many level DC current controls and allocation unit [2], two identical 6 pulse wave Thyristor Three-phase unsteady flows bridge [3] and [4], the phase-shifting transformer composition that the Y windings [5] and Δ winding [6] of a Y winding [7] and two 30 degree of mutual deviations are constituted, uses Two three-phase unsteady flows bridge [3] and [4] produce with the control strategy of asymmetrical current, it is specific with (2) formula by (1) formula respectively Rule of conversion control generation is mutually asymmetric, and Y windings [34] electric current and Δ winding [35] electric current that phase is also differed, and makes shifting The electric current of phase transformer outlet side Y shape winding [36] is sine-wave current, and Y is controlled by the particular transform rule of (1) formula and (2) formula Three-phase unsteady flow bridge and Δ three-phase unsteady flow bridge, result in the electric current of switching device in Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge by setting Fixed triangular current rule change, when the switching device for constituting Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge is for IGCT, Gate circuit transistor gate trigger signal is given when triangular current starts, IGCT is open-minded, during triangular current is zero, IGCT electricity Stream is zero to be forced to shut-off, and a combination of both makes IGCT to be used as full control switch, and the full control of IGCT makes triggering Angle phase shift range is changed into -180 °~180 °, realizes active reactive four quadrant running,

$I_{BY}\left(\mathrm{\ω}t\right)=I_{dc}\{\frac{1}{2}+\underset{k=1}{\overset{\mathrm{\∞}}{\Σ}}\frac{7+4\sqrt{3}}{36{(2k-1)}^2-1}cos\[6(2k-1)\mathrm{\ω}t\]+\underset{k=1}{\overset{\mathrm{\∞}}{\Σ}}\frac{1}{144k^2-1}cos\left(12k\mathrm{\ω}t\right)\}---\left(1\right)$

$I_{B\mathrm{\Δ}}\left(\mathrm{\ω}t\right)=I_{dc}\{\frac{1}{2}-\underset{k=1}{\overset{\mathrm{\∞}}{\Σ}}\frac{7+4\sqrt{3}}{36{(2k-1)}^2-1}cos\[6(2k-1)\mathrm{\ω}t\]+\underset{k=1}{\overset{\mathrm{\∞}}{\Σ}}\frac{1}{144k^2-1}cos\left(12k\mathrm{\ω}t\right)\}---\left(2\right)$

In formula：

I_BY：Y bridge DC currents

I_BΔ：Δ bridge DC current

I_dc：Direct current Storage Unit electric current

K=1,2 ....

2. the static reacance generator control method based on IGCT according to claim 1, wherein described many level DC current is controlled and allocation unit [2] is realized using following principles：

(1) direct current Storage Unit electric current equalization is assigned as m branch road, each branch road is connected to two gate-controlled switches, two can Control switch complementary action, constitutes complementary switch pair, is connected respectively to Y three-phase unsteady flow bridges and Δ three-phase unsteady flow bridge；

(2) complementary switch pair is switched every 30 °/m, making the electric current of inflow Y three-phase unsteady flow bridges increases a branch road amount, while Also the electric current of inflow Δ three-phase unsteady flow bridge is made to reduce by a branch road amount, it is interval by m 30 °/m, when all branch currents all flow After entering Y three-phase unsteady flow bridges, then the electric current of inflow Y three-phase unsteady flow bridges is set to reduce by a branch road amount every 30 °/m, while also making inflow The electric current of Δ three-phase unsteady flow bridge increases a branch road amount, until the electric current for flowing into Y three-phase unsteady flow bridges is reduced to zero, repeats above mistake Journey, it is possible to by direct current Storage Unit electric current by etc. the rule of incremental steps shape triangular wave distribute to Y three-phase unsteady flow bridges and Δ three Phase unsteady flow bridge.

3. there are following characteristics according to the static reacance generator control method based on IGCT described in claim 1：

Ac output current harmonic content increases and reduces with m, and the relation of converter output alternating current THD and m is shown in table 1；

The relation table of table 1.THD and m

m 2 3 4 5 6 7 8 9 THD 7.77% 5.25% 3.99% 3.28% 2.77% 2.45% 2.20% 2.02%

According to table 1, when m >=6, harmonic value is limited in the range of ＜ 3%, using this control method by traditional 12 pulse wave The harmonic content control of the ＞ 8% of converter is in the range of the harmonic content that controllable, satisfaction is actually needed；

Active reactive advanced, delayed can be continuously adjusted, and realize four quadrant running, zero it is active to the specified real power control time≤ 5ms, specified advanced, delayed idle conversion time≤5ms；

Interior on a large scale direct current Storage Unit input and output voltage and electric current can be continuously adjusted, when output or absorption nothing During work(, it is operated under 0 or low current state：When exporting or absorbing active, it is operated under corresponding input and output current status；

It is in zero interval, to make the IGCT of Y three-phase unsteady flow bridges in the electric current of inflow Y three-phase unsteady flow bridges with Sofe Switch theory Commutation, in the interval that the electric current of inflow Δ three-phase unsteady flow bridge is zero, makes the IGCT commutation of Δ three-phase unsteady flow bridge, Y three-phase unsteady flows The IGCT of bridge and Δ three-phase unsteady flow bridge completes commutation under conditions of being zero in electric current, and IGCT is turned off when electric current is zero, Start open-minded when voltage is zero, without switching loss, IGCT working frequency 50Hz, switching frequency is low, thus overall efficiency is high.

4. the static reacance generator control method based on IGCT according to claim 1, wherein described direct current stores Can unit [1], be respectively capacitor, battery, all types of direct current accumulators, various active whole according to practical situations Stream device.