CN102664539B - variable topology thyristor rectifier - Google Patents
variable topology thyristor rectifier Download PDFInfo
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- CN102664539B CN102664539B CN201210146194.7A CN201210146194A CN102664539B CN 102664539 B CN102664539 B CN 102664539B CN 201210146194 A CN201210146194 A CN 201210146194A CN 102664539 B CN102664539 B CN 102664539B
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Abstract
The invention relates to a variable topology thyristor rectifier, which comprises two thyristor bridge rectifiers T1 and T2. The input ends of the T1 and T2 are connected with a single-phase or three-phase isolation alternating current voltage source respectively, and the voltage sources have an electrical angle difference. The negative pole of the output end of the T1 is connected with the positive pole of the output end of the T2 through a switch S1, and the positive pole of the output end of the T1 and the negative pole of the output end of the T2 are connected with an LC filter consisting of an inductor L and a capacitor C. The two ends of the capacitor C are connected with an inverter of which the output end is connected with a power grid. The T1 and the T2 run in different modes according to different electrical angles, the sinusoidal voltages of the two different electrical angles are superposed to form sinusoidal input voltage grades of different amplitudes, and input voltages are selected according to different load conditions to realize minimum voltage input under an on-load running condition; a trigger angle of a thyristor is as small as possible, so that a high-power factor running condition is created; and current peak prediction control is adopted for a plurality of running modes to realize the dynamic switching of an online mode.
Description
Technical field
The present invention relates to a kind of variable topological silicon controlled rectifier of high power capacity.
Background technology
All-controlling power electronics device (turn-on and turn-off of device all can by gate signal control), especially IGBT(Insulated Gate Bipolar Transistor, gated transistor) power grade restricted further developing of power electronic equipment capacity.The IGBT device withstand voltage grade that present stage is most widely used is at 1.7KV.Though the IGBT of 3.3KV and 6.5KV puts it into commercial operation, compared with the device of 1.7KV, price Capacity Ratio is not high.In addition, high requirement of withstand voltage increases sharply the on-state voltage drop of switching device and switching loss.Switching tube loss increases, and except loss in efficiency, also can cause making device radiation cost increase rapidly, loses competitiveness economically.Because silicon semiconductor device need to can normally be worked between-40 DEG C～170 DEG C, in actual engineering, need according to the heat abstractor of the suitable air-cooled or water-cooled of the power loss design of electronic power switch device.Switching device outside is close to or is wrapped up bulky aluminum heat channel, and heat abstractor cost is suitable with power electronic device cost, sometimes even exceedes the cost of switching device own.
For adapting to present stage IGBT device capacity, in the current transformer of the high power capacities such as wind power generation, wind driven generators more than 1.5MW adopts multiple current transformer parallel connections to share capacity conventionally.This scheme has just maintained the current transformer cost of unit power conversion, cannot reach the final purpose of development high-power wind-driven generator group reduction unit cost of electricity-generating.
Thyristor is commercialization controllable semiconductor device present stage with maximum voltage withstand class.Its technology maturation, stable performance, has very high capacity cost ratio.Its maximum voltage withstand class reaches 12kV, still has the withstand voltage of 4.8kV under the current capacity of 5kA.Thyristor is introduced to wind turbine generator more than 2MW, and the output voltage of wind-driven generator and the electric pressure of current transformer will no longer be subject to the restriction of IGBT device withstand voltage grade.
But mainly there is following problem in silicon controlled rectifier: 1., because thyristor rectifier bridge has dropping voltage characteristic, cannot directly apply to AC input voltage and change greatly, but DC bus-bar voltage still keeps constant wind generator system.2. because silicon controlled rectifier adopts phase control method, in underloaded situation, cause serious harmonic pollution.
Summary of the invention
Object of the present invention is exactly for addressing the above problem, a kind of variable topological silicon controlled rectifier is provided, it is taking many arteries and veins of variable topological structure thyristor rectifier as front end, to strengthen the wide voltage adaptation ability of silicon controlled rectifier, utilize the power capacity advantage of thyristor, in the time being applied to wind power generation current-transformation device, variable topological silicon controlled rectifier is combined with six-phase generator, all there is three-level inverter rear end, the high-voltage variable ratio of having realized rectifier, has improved the disposable electric pressure of current transformer and power grade; In the time being applied in many arteries and veins rectifying device, reduce silicon controlled rectifier due to the harmonic pollution that adopts phase control method to cause under light load condition.
For achieving the above object, the present invention adopts following technical scheme:
A kind of variable topological silicon controlled rectifier, it comprises two thyristor rectifier bridge T1, T2, the input of described two thyristor rectifier bridge T1, T2 is connected with single-phase or three isolated alternating-current voltage sources respectively, between two isolated voltage source, has electrical degree difference; The negative pole of output end of described thyristor rectifier bridge T1 is connected with the output head anode of T2, is connected to the LC filter of inductance and electric capacity composition between the output head anode of T1 and the negative pole of output end of T2; Capacitor C is connected with inverter input terminal, and inverter output end is connected with electrical network; Two thyristor rectifier bridges are according to the difference of electrical degree, the sinusoidal voltage of two different electrical degrees is superposeed mutually, form the sinusoidal input voltage grade of different amplitudes, according to different loading conditions, input voltage is selected, realize the minimum voltage input meeting in load running situation; Make the Trigger Angle of thyristor as far as possible little simultaneously, thereby obtain higher power factor service conditions; Conversion between different electric pressures adopts current peak PREDICTIVE CONTROL, realizes the dynamic switching of line model.
Described current peak control procedure is AC-input voltage v
indirect voltage V with capacitor C
dcdifference carry out integration being greater than at 1 o'clock, work as v
in=V
dcmoment integration reach maximum, will be now integral result keep, integration zero clearing simultaneously; At the v in next cycle
in> V
dctime, calculate in real time on maximum integration and each sampled point the difference of integration in real time, except being added with electric current real-time sampling value after inductance L, then compare with current-order, when zero passage, send into thyristor gating circuit.
Described dynamic switching refers to the input voltage v of two different electric pressures that independently voltage source obtains by Phase Stacking
in; Integration by each input voltage grade in inductance L calculates simultaneously, in each commutating period, according to the weight of load, select the voltage of a Trigger Angle minimum as actual implementation strategy, like this in the situation that of load changing or input voltage variation, the Trigger Angle obtaining according to current peak forecast Control Algorithm comes into operation at once, realize under various input voltage state, the topological structure fast not affecting under power input condition switches, and obtains the High Power Factor operation under different loads and voltage condition.
The present invention more in the past variable topological rectifying device has following outstanding advantage:
1. use the ball bearing made using of thyristor and diode combinations to realize high-voltage variable ratio, rectifier terminal is no longer the bottleneck of restriction wind-force wind generator gradation voltage generator and power grade.
2. a difficult problem of switching for dynamic topology in the course of work, adopt current peak PREDICTIVE CONTROL [CortesP, KazmierkowskiMP, KennelRM, et al.Predictive Control in Power Electronics and Drives[J] .Industrial IEEE Transactions on Electronics, 2008, 55 (12): 4312-4324], [Sun Xiangdong, Ren Biying, Zhong Yanru etc. the application [J] of filter inductance On-line Estimation method in predicted current control. electrotechnics journal, 2009, 24 (7): 150～156], [Yu Rongrong, Wei Xueye, Wu little Jin etc. a kind of modified model predicted current control algolithm [J]. electrotechnics journal, 2010, 24 (7): 100～107], [Yang Yong, Ruan Yi, Ye Binying etc. three-phase grid-connected inverter dead beat current forecasting control method [J]. Proceedings of the CSEE, 2009, 29 (33): 40-46] substituted PI(Proportional Integral, proportional integral) control, take full advantage of the predictability of thyristor turn-off time, eliminate the current break in topological transformation process, realize series-parallel seamless switching in variable topological process, improve electric current performance of dynamic tracking.
3. rectifier has all kept the characteristic of many arteries and veins rectification in series parallel structure, reduces generator pulsation, has improved the utilance of device (rectifier bridge).
4. while being applied to wind power generation current-transformation device, variable topological silicon controlled rectifier is combined with six-phase generator, and all there is three-level inverter rear end, has realized the high-voltage variable ratio of rectifier, has improved the disposable electric pressure of current transformer and power grade;
5., while being applied in many arteries and veins rectifying device, reduce silicon controlled rectifier due to the harmonic pollution that adopts phase control method to cause under light load condition.
Brief description of the drawings
Fig. 1 is convertor assembly figure of the present invention;
Fig. 2 is the three-phase six arteries and veins Thyristor Controlled rectifiers that adopt current peak PREDICTIVE CONTROL;
Alternating voltage and DC inductance current waveform when Fig. 3 adopts current peak PREDICTIVE CONTROL while being steady operation;
Fig. 4 is that Current Control Strategy realizes block diagram;
Fig. 5 is the state diagram of thyristor in 1-6-7-12 operational mode 1;
Fig. 5 a is the voltage phasor-diagram of equal value of operational mode 1;
Fig. 6 is the state diagram of thyristor in 4-5-9-10 operational mode 2;
Fig. 6 a is the voltage phasor-diagram of equal value of operational mode 2;
Fig. 7 is the state diagram of thyristor in 1-6-7-8 operational mode 3;
Fig. 7 a is the voltage phasor-diagram of equal value of operational mode 3;
Fig. 8 is the state diagram of thyristor in 2-3-7-12 operational mode 4;
Fig. 8 a is the voltage phasor-diagram of equal value of operational mode 4;
Fig. 9 is the state diagram of thyristor in 1-2-8-9 operational mode 5;
Fig. 9 a is the voltage phasor-diagram of equal value of operational mode 5;
Figure 10 is the state diagram of thyristor in 1-6-9-10 operational mode 6;
Figure 10 a is the voltage phasor-diagram of equal value of operational mode 6;
Figure 11 is that selection is calculated in the optimization of multi-mode electric current peak value PREDICTIVE CONTROL
Embodiment
Below in conjunction with accompanying drawing and embodiment, the present invention will be further described.
Wind power generation current-transformation device taking variable topological silicon controlled rectifier as front end proposed by the invention as Figure 1-Figure 11.
Variable topological silicon controlled rectifier comprises two thyristor rectifier bridge T1, T2, and the input of described two thyristor rectifier bridge T1, T2 can be connected with single-phase or three isolated alternating-current voltage sources respectively, between two isolated voltage source, has electrical degree difference.Described two negative pole of output end of thyristor rectifier bridge T1 and the output head anode of T2 are connected, the LC filter that the output head anode of T1 and the negative pole of output end of T2 are all made up of inductance and electric capacity.
Variable topological silicon controlled rectifier comprises different operating voltage operational modes.While differing 20 ° with two electrical degrees (phase angle of power supply sinusoidal waveform) below, as an example, the different operational modes of rectifier are described.In different operational modes, the sinusoidal voltage of two different electrical degrees superposes mutually, forms the sinusoidal input voltage grade of different amplitudes.
Obtain the object of the sinusoidal input voltage grade of different amplitudes, to select input voltage according to different loading conditions, realization meets the minimum voltage input in load running situation, make the Trigger Angle (line voltage equal point to the electric angle between trigger point) of thyristor as far as possible little, thereby obtain higher power factor service conditions.
Between multiple operational modes, adopt control strategy, realize the dynamic switching of line model.Adopting the main target of control strategy is to realize in the situation that does not affect power stage, realizing online operational mode and switching.Intend adopting following current peak forecast Control Algorithm to realize expection:
1. the general principle of current peak PREDICTIVE CONTROL
After disconnecting according to switch S 1, the symmetry of rectifier bridge T1 and T2, describes control strategy principle as an example of T1 example, as shown in Figure 2.
Three level grid-connected inverters keep DC voltage V in capacitor C
dcstable.Can find out inductive current i from the alternating voltage of Fig. 3 and the stable state waveform of DC side electric current
lthe moment equating with direct voltage in each AC-input voltage reaches maximum, as v
cawith V
dcthe moment t crossing
0 [16].As triggered at this moment v
cb, the weber integration of alternating voltage and direct voltage difference will cause the current change quantity Δ i of rising in inductance L
l.Δ i
lat v
cb=V
dct
1moment arrives maximum, is defined as:
Can trigger thyristor control curent change and without obtain maximum Δ i in each cycle by time delay
l.In the three-phase system of balance, if at period t
1-t
2interior any time t triggers thyristor, so at t-t
2in period internal inductance by occur curent change Δ i
lwith current increment maximum Δ i
l, maxwith the pass of inductance two ends weber integration be:
Be Δ i
lcan carry out integration accumulation in each sampling instant by formula (2) calculates.Therefore, if obtain at the peak point of electric current the current i of expecting
*, the triggering moment t of thyristor should meet so: trigger the transient current i on moment inductance
l(t) with the ascending current Δ i that triggers rear inductance
l(t) sum and expectation electric current (i
*) equate:
i
*＝i
L(t)+Δi
L(t).(3)
I in formula
l(t) the real-time current sampling that can pass through obtains; Judge whether to meet according to formula (3) condition that triggers respective thyristor conducting.
Control algolithm realizes block diagram as shown in Figure 4.AC-input voltage v
in(v
in=v
ab, v
bc...) and direct voltage V
dcdifference carry out integration being greater than at 1 o'clock and sending into integrator, work as v
in=V
dcmoment integration reach maximum, the result in integrator is now sent into sampling and is kept (S/H) device, integrator zero clearing simultaneously.At the v in next cycle
in> V
dctime, calculate in real time on maximum integration and each sampled point the difference of integration in real time, except being added with electric current real-time sampling value after inductance L, then compare with current-order, when zero passage, send into thyristor gating circuit.
2. the mode of operation of different electric pressures
Because two independent isolating power supplys exist the difference between electric angle, therefore the stack of the sinusoidal voltage of out of phase has formed the different input voltage amplitude of amplitude.While differing 20 ° with two electrical degrees (phase angle of power supply sinusoidal waveform) below, as an example, illustrate that rectifier, in the time of the voltage stack that adopts different voltage-phases, obtains different input voltage amplitudes.
For example, when simultaneously conducting of thyristor 1-6-7-12, the input voltage that two groups of thyristor rectifier bridges obtain is V
1=U
aB+ U
ab,
At this moment input voltage amplitude is higher, becomes operational mode 1.In the situation of operational mode 1, two insulating power supplies are realized phase place and are approached the two superimposed of (being separated by 20 °) most.In the time of thyristor 4-5-9-10 conducting simultaneously, two groups of input voltage V that thyristor rectifier bridge DC side obtains
2=U
ca-U
aB, become operational mode 2.In the situation of operational mode 2, two insulating power supplies are realized two groups of sinusoidal voltage amplitude stacks that differ 40 °.Operational mode 3,4,5,6 by that analogy, obtains the sine-wave current stack of out of phase, obtains the voltage of different amplitude level.As shown in Fig. 5-Figure 11.
3. the online switching between mode of operation
As mentioned above, the input voltage v of two different electric pressures that independently voltage source obtains by Phase Stacking
in.In order to obtain the conversion of line model in multiple mode of operation runnings, the input voltage of all patterns is combined in integration in inductance L and calculates according to current peak predictive control algorithm in 1 simultaneously.Adopt the sharpest edges of current peak PREDICTIVE CONTROL to be, can realize the leading calculating of various input voltage condition.In each commutating period, controller, according to controlling target call, is optimized all result of calculation to calculate and selects, and selects optimal result as tactful execution result, as shown in figure 11.For example, the highest during as optimization aim in power factor, be chosen in Trigger Angle minimum in all result of calculation result as actual implementation strategy.Due to the leading calculation features of current peak control method, the Trigger Angle obtaining according to above-mentioned peak value forecast Control Algorithm comes into operation at once, realize under various input voltage state, the topological structure fast not affecting under power input condition switches, and obtains the High Power Factor operation under different loads and voltage condition.
Wind power generation current-transformation device taking variable topological silicon controlled rectifier as front end of the present invention.Utilize the power capacity advantage of thyristor, expanded the disposable electric pressure of wind power generation current-transformation device and power grade, saved device cost.Current peak forecast Control Algorithm has not only realized dynamically controlling fast of DC side inductive current, and eliminate the current break in two rectifier bridge topological structure handoff procedures, rectifier series boosting and parallel extended between take over seamlessly, solved the most crucial problem that perplexs dynamic variable topological structure current transformer.This application of installation can reduce current transformer cost greatly in megawatt-grade high-power wind turbine generator, will have bright prospects and development potentiality.
Claims (2)
1. a variable topological silicon controlled rectifier, it is characterized in that, it comprises two thyristor rectifier bridge T1, T2, and the input of described two thyristor rectifier bridge T1, T2 is connected with single-phase or three isolated alternating-current voltage sources respectively, between two isolated voltage source, has electrical degree difference; The negative pole of output end of described thyristor rectifier bridge T1 is connected with the output head anode of T2, is connected to the LC filter of inductance and electric capacity composition between the output head anode of T1 and the negative pole of output end of T2; Capacitor C is connected with inverter input terminal, and inverter output end is connected with electrical network; Two thyristor rectifier bridges are according to the difference of electrical degree, the sinusoidal voltage of two different electrical degrees is superposeed mutually, form the sinusoidal input voltage grade of different amplitudes, according to different loading conditions, input voltage is selected, realize the minimum voltage input meeting in load running situation; Make the Trigger Angle of thyristor as far as possible little simultaneously, thereby obtain higher power factor service conditions; Conversion between different electric pressures adopts current peak PREDICTIVE CONTROL, realizes the dynamic switching of line model;
Described dynamic switching refers to the input voltage v of two different electric pressures that independently voltage source obtains by Phase Stacking
in; Integration by each input voltage grade in inductance L calculates simultaneously, in each commutating period, according to the weight of load, select the voltage of a Trigger Angle minimum as actual implementation strategy, like this in the situation that of load changing or input voltage variation, the Trigger Angle obtaining according to current peak forecast Control Algorithm comes into operation at once, realize under various input voltage state, the topological structure fast not affecting under power input condition switches, and obtains the High Power Factor operation under different loads and voltage condition.
2. variable topological silicon controlled rectifier as claimed in claim 1, is characterized in that, described current peak forecast Control Algorithm is AC-input voltage v
indirect voltage v with capacitor C
dcdifference carry out integration being greater than at 1 o'clock, work as v
in=v
dcmoment integration reach maximum, will be now integral result keep, integration zero clearing simultaneously; At the v in next cycle
in> v
dctime, calculate in real time on maximum integration and each sampled point the difference of integration in real time, except being added with electric current real-time sampling value after inductance L, then compare with current-order, when zero passage, send into thyristor gating circuit.
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| CN103051213B (en) * | 2012-12-11 | 2014-12-17 | 国网智能电网研究院 | Energy replenishing power supply system and control method thereof for MMC valve |
| RU2540110C2 (en) * | 2013-04-23 | 2015-02-10 | Общество с ограниченной ответственностью "Научно-производственный центр "Судовые электротехнические системы" (ООО "НПЦ "СЭС") | Reversible frequency converter |
| CN116247952A (en) * | 2023-05-08 | 2023-06-09 | 国网山西省电力公司临汾供电公司 | Three-phase bridge rectifier converter with controllable three bridge arm power |
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| US7061743B2 (en) * | 2002-10-30 | 2006-06-13 | Korea Electric Power Corporation | Multi-pulse HVDC system using auxiliary circuit |
| CN101882880A (en) * | 2010-07-02 | 2010-11-10 | 浙江大学 | Multi-generator set multi-pulse rectifying method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2010057306A (en) * | 2008-08-29 | 2010-03-11 | Yanmar Co Ltd | Power conversion circuit |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7061743B2 (en) * | 2002-10-30 | 2006-06-13 | Korea Electric Power Corporation | Multi-pulse HVDC system using auxiliary circuit |
| CN101882880A (en) * | 2010-07-02 | 2010-11-10 | 浙江大学 | Multi-generator set multi-pulse rectifying method |
Non-Patent Citations (2)
| Title |
|---|
| JP特开2010-57306A 2010.03.11 |
| 王仕韬等.具有快速电流动态响应的晶闸管整流控制器.《浙江大学学报（工学版）》.2012,第46卷(第2期),189-193. * |
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