CN102510062B - Improved space vector single period control method and device for active power filter - Google Patents

Abstract

The invention belongs to the field of active power filters, and provides an improved space vector single period control method used for simplifying an integral control system. In order to achieve the purpose, the method comprises the following steps: an active power filter main circuit equation based on a single period control idea is simplified; a three-phase power supply voltage zone regionalization condition judgment table is used for judge that a voltage vector of a three-phase AC is located in a zone I, II or III; on-off state da, db or dc of bridge arms on a corresponding phase can be obtained via a judgment result, and an active power filter single period control equation in the zone I, II and III is obtained; Vm is regulated and controlled through that deviation delta vd of the voltage on the active power filter DC side is regulated by proportional integral (PI), and voltage Vd of the DC side is required to be kept during the regulation process, thus a required active power under the current load condition is obtained. The invention is mainly applied in active power wave filtering.

Description

Room for improvement vector monocyclic control method and the device of Active Power Filter-APF

Technical field

The invention belongs to Active Power Filter-APF field, be specifically related to room for improvement vector monocyclic control method and the device of Active Power Filter-APF.

Background technology

In harmonic suppressing method, Active Power Filter-APF is compared passive power filter obvious advantage, as can be compensated each harmonic, can carry out real-Time Compensation etc. to the reactive power changing simultaneously, make it become gradually the Main Means of harmonic carcellation.But traditional Active Power Filter-APF all needs first to detect harmonic current, and then apply the control methods such as hysteresis current control, triangular current control and export identical with it offset current, therefore the design of whole control system is comparatively complicated.

Summary of the invention

For overcoming the deficiencies in the prior art, on traditional Cycle Control basis, further improve, provide a kind of whole control system to realize the room for improvement vector monocyclic control method of the Active Power Filter-APF of simplifying, for achieving the above object, the technical scheme that the present invention takes is, a kind of room for improvement vector monocyclic control method of Active Power Filter-APF, by means of lower array apparatus, realize: in three full control switching tubes, the transmitting set pair of each pipe should be connected on the collector electrode of each pipe in other three switching tubes, each switching tube forms a brachium pontis, the tie point of aforementioned emitter and collector electrode is brachium pontis is connected mid point, the emitter of other three switching tubes links together and the resistance by two serial connections is connected on the collector electrode that described three switching tubes link together, the emitter of each switching tube respectively connects the positive pole of a diode, the negative pole of diode is connected to the collector electrode of the coupled switching tube of emitter, the described emitter linking together, between collector electrode, be provided with electric capacity, to the three-phase alternating current of nonlinear load power supply is every, by an inductance correspondence, be connected to an aforementioned aforementioned connection mid point respectively mutually, three-phase alternating current is every to be connected respectively to mutually based on space vector Cycle Control arithmetic unit, and the tie point between described two resistance is also connected on described arithmetic unit,

To be based on Cycle Control thought Active Power Filter-APF main circuit equation simplification:

$\left[\begin{array}{c}{v}_{\mathrm{sa}}\\ v_{\mathrm{sb}}\\ v_{\mathrm{sc}}\end{array}\right]=\frac{1}{3}{V}_d\left[\begin{array}{ccc}2& -1& -1\\ -1& 2& -1\\ -1& -1& 2\end{array}\right]\left[\begin{array}{c}{d}_a\\ d_b\\ d_c\end{array}\right]---\left(6\right)$

V in above formula _sa, v _sb, v _scfor three-phase alternating voltage, d _a, d _band d _ccorrespond to respectively the duty ratio of a brachium pontis above connection mid point, V _dfor electric capacity both end voltage;

Condition judgment table is divided in three-phase mains voltage region

Region	I	II	III
				Condition 1	v sb-v sc＞0	v sc-v sa＞0	v sa-v sb＞0
Condition 2	v sc-v sa≤0	v sa-v sb≤0	v sb-v sc≤0

The on off states different according to triode form six fundamental space voltage vector V ₁-V ₆, between each space voltage vector, angle is 60 degree, establishes three bit digital and represents brachium pontis on off operating mode, represents conducting during for " 1 ", turn-offs first to the 3rd first to the 3rd of representing successively three-phase alternating current, six fundamental space voltage vector V for " 0 " represents ₁-V ₆arrange counterclockwise successively, the brachium pontis on off operating mode that each space voltage vector is corresponding is followed successively by (100), (110), (010), (011), (001), (101), V ₁counterclockwise to V ₃region is interval I, V ₃counterclockwise to V ₅region is interval II, V ₅counterclockwise to V ₁region is interval III, and the voltage vector of being divided condition judgment table differentiation three-phase alternating current by three-phase mains voltage region is arranged in interval I, II or III, by differentiating result, obtains the corresponding brachium pontis on off state d that goes up mutually _a, d _bor d _c, and substitution formula (6), obtain at the Active Power Filter-APF Cycle Control equation in I, II, III interval as follows successively:

$\left\{\begin{array}{c}{d}_a{V}_m=2R_s{i}_{\mathrm{sa}}+R_s{i}_{\mathrm{sb}}\\ d_b{V}_m=2R_s{i}_{\mathrm{sb}}+R_s{i}_{\mathrm{sa}}\\ d_c=0\end{array}\right.---\left(12\right)$

$\left\{\begin{array}{c}{d}_a=0\\ d_b{V}_m=2R_s{i}_{\mathrm{sb}}+R_s{i}_{\mathrm{sc}}\\ d_c{V}_m=2R_s{i}_{\mathrm{sc}}+R_s{i}_{\mathrm{sb}}\end{array}\right.---\left(\text{13}\right)$

$\left\{\begin{array}{c}{d}_a{V}_m=2R_s{i}_{\mathrm{sa}}+R_s{i}_{\mathrm{sc}}\\ d_b=0\\ d_c{V}_m=2R_s{i}_{\mathrm{sc}}+R_s{i}_{\mathrm{sa}}\end{array}\right.---\left(14\right)$

V in formula _ma physical quantity with actual power direct ratio, by Active Power Filter-APF DC voltage deviation delta v _dcarry out proportion integral control and regulate and control V _m, in adjustment process, need to guarantee DC voltage V _dremain unchanged, obtain active power required under present load condition.

By to Active Power Filter-APF DC voltage deviation delta v _dcarry out proportion integral control and regulate and control V _mbe specially: by the Active Power Filter-APF Cycle Control equation in I, II, III interval and each interval parameter option table of the Active Power Filter-APF of Cycle Control, obtain current i _s1, i _s2

Each interval parameter option table of the Active Power Filter-APF of Cycle Control

Interval	R s.i s1	R s.i s2	S a	S b	S c
						I	R s.i sa	R s.i sb	s 1	s 2	0
II	R s.i sb	R s.i sc	0	s 1	s 2
						III	R s.i sc	R s.i sa	s 2	0	s 1

First according to the voltage vector of three-phase mains voltage region division condition judgment table differentiation three-phase alternating current in three-phase mains voltage region division condition judgment table, be arranged in interval I, II or III and generate selection signal; According to selecting signal, according to each interval parameter option table of the Active Power Filter-APF of Cycle Control, select corresponding phase current; According to selecting each interval parameter option table of Active Power Filter-APF of signal and Cycle Control, select the switching drive signal that each triode is corresponding, S in table _arepresent that one in three-phase go up the switching signal s of brachium pontis mutually _ap, due to the complementary conducting of its upper and lower bridge arm, this descends brachium pontis to S mutually _anegate can obtain the start pulse signal s of lower brachium pontis _an, other two-phases are similar successively, s ₁, s ₂be respectively R _s.i _s1, R _s.i _s2acting in conjunction is held in two rest-set flip-flop S, the start pulse signal of the switching tube of this two trigger Q ends output.

A kind of room for improvement vector Cycle Control device of Active Power Filter-APF, comprise, in three full control switching tubes, the transmitting set pair of each pipe should be connected on the collector electrode of each pipe in other three switching tubes, each switching tube forms a brachium pontis, the tie point of aforementioned emitter and collector electrode is brachium pontis is connected mid point, the emitter of other three switching tubes links together and the resistance by two serial connections is connected on the collector electrode that described three switching tubes link together, the emitter of each switching tube respectively connects the positive pole of a diode, the negative pole of diode is connected to the collector electrode of the coupled switching tube of emitter, the described emitter linking together, between collector electrode, be provided with electric capacity, to the three-phase alternating current of nonlinear load power supply is every, by an inductance correspondence, be connected to an aforementioned aforementioned connection mid point respectively mutually, three-phase alternating current is every to be connected respectively to mutually based on space vector Cycle Control arithmetic unit, tie point between described two resistance is also connected on described arithmetic unit, in addition, also comprise based on space vector Cycle Control arithmetic unit device, this arithmetic unit comprises: vector interval division part, be used for according to being positioned at interval I as the voltage vector for three-phase mains voltage region division condition judgment table judgement differentiation three-phase alternating current of weighing as described in 1, in II or III, electric current is selected part, be used for according to three phase mains phase current, aforementioned differentiation result, form the output of two-way phase current, the phase current output of every road is successively through amplifier, adder outputs to the in-phase input end of corresponding amplifier, the phase current output of every road is also connected respectively in the adder of the aforementioned process successively of another road electric current output, the output of corresponding amplifier is connected to the S end of corresponding rest-set flip-flop, Q ' the end of corresponding rest-set flip-flop is through being connected to resetting integrator with door, capacitance voltage and reference voltage are jointly through adder, proportional controller outputs to resetting integrator, resetting integrator outputs to the inverting input of corresponding amplifier, clock source is connected to the R end of rest-set flip-flop, logic selects circuit to drive signal according to the differentiation result output brachium pontis between the voltage vector location of the output of rest-set flip-flop and cross streams electricity.

The present invention has following technique effect:

Based on room for improvement vector monocyclic control method with respect to traditional space vector monocyclic control method, space vector region selects circuit, current selecting circuit and logic to select circuit part all greatly to simplify, thereby overall structure of the present invention is simplified, optimizes.

2. adopt the present invention can make the whole Control System Design of Active Power Filter-APF simpler, and obtain good control effect, adopt compensation after-current resultant distortion rate to drop to 5.00%, met the regulation in national standard quality of power supply utility network harmonic wave.

Accompanying drawing explanation

Fig. 1 room for improvement vector APF with one-cycle control schematic diagram.

Fig. 2 current transformer space voltage vector subregion.

Fig. 3 is based on room for improvement vector calculus Cycle Control schematic diagram.

Before and after Fig. 4 compensates, A phase source current oscillogram 3 is PTAT current source circuit figure.In figure, a) A phase source current waveform before compensation, b) A phase source current waveform after compensation.

A phase source current FFT spectrogram before and after Fig. 5 compensates.In figure, a) A phase source current FFT frequency spectrum before compensation, b) A phase source current FFT frequency spectrum after compensation.

Embodiment

(1) Active Power Filter-APF main circuit establishing equation:

In Fig. 1, establish current transformer output three-phase phase voltage and be respectively v _ca, v _cb, v _cc, for three-phase symmetrical system, the math equation of describing current transformer main circuit can be expressed as

$\left[\begin{array}{c}{v}_{\mathrm{ca}}\\ v_{\mathrm{cb}}\\ v_{\mathrm{cc}}\end{array}\right]=L\left[\begin{array}{c}\frac{{\mathrm{di}}_{\mathrm{ca}}}{\mathrm{dt}}\\ \frac{{\mathrm{di}}_{\mathrm{cb}}}{\mathrm{dt}}\\ \frac{{\mathrm{di}}_{\mathrm{cc}}}{\mathrm{dt}}\end{array}\right]+\left[\begin{array}{c}{v}_{\mathrm{sa}}\\ v_{\mathrm{sb}}\\ v_{\mathrm{sc}}\end{array}\right]---\left(1\right)$

In Fig. 1, three-phase inverter has 6 power switch pipes, and wherein the switch on each brachium pontis is at complementary state, therefore can define switch function and be

(i＝a，b，c) (2)

The voltage of current transformer main circuit output can be expressed as

$\left[\begin{array}{c}{v}_{\mathrm{ca}}\\ v_{\mathrm{cb}}\\ v_{\mathrm{cc}}\end{array}\right]=\frac{1}{3}{V}_d\left[\begin{array}{ccc}2& -1& -1\\ -1& 2& -1\\ -1& -1& 2\end{array}\right]\left[\begin{array}{c}{S}_a\\ S_b\\ S_c\end{array}\right]---\left(3\right)$

Now suppose at a switch periods T _sin, on main circuit current transformer abc three-phase, the time of brachium pontis conducting is respectively d _at _s, d _bt _s, d _ct _s, first in the prerequisite of the complementary conducting of each mutually upper and lower brachium pontis switching tube, descend the time of brachium pontis conducting to be respectively (1-d _a) T _s, (1-d _b) T _s(1-d _c) T _s, d wherein _a, d _band d _cit is respectively the duty ratio of brachium pontis conducting on abc three-phase.In a switch periods, formula (3) can be write out

$\left[\begin{array}{c}{v}_{\mathrm{ca}}\\ v_{\mathrm{cb}}\\ v_{\mathrm{cc}}\end{array}\right]=\frac{1}{3}{V}_d\left[\begin{array}{ccc}2& -1& -1\\ -1& 2& -1\\ -1& -1& 2\end{array}\right]\left[\begin{array}{c}{d}_a\\ d_b\\ d_c\end{array}\right]---\left(4\right)$

Wushu (4) substitution formula (1) can obtain

$\frac{1}{3}{V}_d\left[\begin{array}{ccc}2& -1& -1\\ -1& 2& -1\\ -1& -1& 2\end{array}\right]\left[\begin{array}{c}{d}_a\\ d_b\\ d_c\end{array}\right]=L\left[\begin{array}{c}\frac{{\mathrm{di}}_{\mathrm{ca}}}{\mathrm{dt}}\\ \frac{{\mathrm{di}}_{\mathrm{cb}}}{\mathrm{dt}}\\ \frac{{\mathrm{di}}_{\mathrm{cc}}}{\mathrm{dt}}\end{array}\right]+\left[\begin{array}{c}{v}_{\mathrm{sa}}\\ v_{\mathrm{sb}}\\ v_{\mathrm{sc}}\end{array}\right]---\left(5\right)$

(2) based on Cycle Control thought Active Power Filter-APF main circuit equation simplification:

For the voltage Ldi/dt at Active Power Filter-APF outlet inductance two ends, suppose at a switch periods T _sthe stage of opening electric current increase, at off-phases electric current, reduce, because switching frequency is enough large, can think that the voltage Ldi/dt at switch periods internal inductance two ends is 0, by formula (5), can be obtained

$\left[\begin{array}{c}{v}_{\mathrm{sa}}\\ v_{\mathrm{sb}}\\ v_{\mathrm{sc}}\end{array}\right]=\frac{1}{3}{V}_d\left[\begin{array}{ccc}2& -1& -1\\ -1& 2& -1\\ -1& -1& 2\end{array}\right]\left[\begin{array}{c}{d}_a\\ d_b\\ d_c\end{array}\right]---\left(6\right)$

(3) room for improvement vector is divided and judgment basis:

Be illustrated in figure 2 Active Power Filter-APF current transformer space voltage vector distribution map, according to six fundamental space voltage vector V in the different on off state composition diagram of converter switches pipe ₁～V ₆, V for example ₁(100) in, " 100 " represent that respectively a goes up mutually brachium pontis conducting, b and goes up mutually that brachium pontis turn-offs and c go up brachium pontis shutoff mutually.

If power supply phase voltage is v _sa, v _sb, v _sc, by three-phase voltage from abc coordinate system transformation to the xy transformation of coordinates formula that is mutually 60 degree suc as formula shown in (7)

$\left[\begin{array}{c}{v}_{\mathrm{sx}}\\ v_{\mathrm{sy}}\end{array}\right]=C\left[\begin{array}{c}{v}_{\mathrm{sa}}\\ v_{\mathrm{sb}}\\ v_{\mathrm{sc}}\end{array}\right]=\left[\begin{array}{ccc}1& -1& 0\\ 0& 1& -1\end{array}\right]\left[\begin{array}{c}{v}_{\mathrm{sa}}\\ v_{\mathrm{sb}}\\ v_{\mathrm{sc}}\end{array}\right]---\left(7\right)$

Make supply voltage vector V _s=v _sxx+v _sxy, can show that by Fig. 4 the decision condition of supply voltage vector region is shown in Table 1.

Rule of judgment when table 1 three-phase mains voltage is divided six sectors

Sector

1

2

3

4

5

6

Condition 1

v sx＞0

v sx＜0

v sx＜0

v sx＜0

v sx＞0

v sx＞0

Condition 2

v sy＞0

v sy＞0

v sy＞0

v sy＜0

v sy＜0

v sy＜0

Condition 3

--

|v sx|＜|v sy|

|v sx|＞|v sy|

--

|v sx|＜|v xy|

|v sx|＞|v sy|

In Fig. 2, due to fundamental space vector V in region 1,2 ₁～V ₃c be mutually 0, therefore region I can be merged into in region 1,2, in like manner region II, III are merged into respectively in region 3,4 and region 5,6.By decision condition in table 1 and each variable is carried out to contravariant and change to abc coordinate system and can draw the decision condition under new zoning, as shown in table 2.

Condition judgment is divided in table 2 three-phase mains voltage region

Region	I	II	III
				Condition 1	v sb-v sc＞0	v sc-v sa＞0	v sa-v sb＞0
Condition 2	v sc-v sa≤0	v sa-v sb≤0	v sb-v sc≤0

(4) Active Power Filter-APF room for improvement vector monocyclic control method is realized:

Suppose that supply voltage vector is positioned at I district shown in Fig. 2, can find out that c goes up mutually brachium pontis and turn-offs all the time, i.e. d _c=0.By d _cin=0 substitution formula (6), can obtain

$\left\{\begin{array}{c}{V}_d{d}_a=2v_{\mathrm{sa}}+v_{\mathrm{sb}}\\ V_d{d}_b=2v_{\mathrm{sb}}+v_{\mathrm{sa}}\\ d_c=0\end{array}\right.---\left(8\right)$

The control target of the three phase active electric power filter of Cycle Control is to realize whole circuit unity power factor control, after compensation, makes the total load of power supply be resistive, and establishing all-in resistance is R _e, have

$\left\{\begin{array}{c}{v}_{\mathrm{sa}}=R_e{i}_{\mathrm{sa}}\\ v_{\mathrm{sb}}=R_e{i}_{\mathrm{sb}}\\ v_{\mathrm{sc}}=R_e{i}_{\mathrm{sc}}\end{array}\right.---\left(9\right)$

Formula (9) substitution formula (8) can be obtained

$\left\{\begin{array}{c}{d}_a{V}_d/R_e=2i_{\mathrm{sa}}+i_{\mathrm{sb}}\\ d_b{V}_d/R_e=2i_{\mathrm{sb}}+i_{\mathrm{sa}}\\ d_c=0\end{array}\right.---\left(10\right)$

If sampling resistor is R _s, and order

$V_m=\frac{R_s}{R_e}{V}_d---\left(11\right)$

Formula (11) substitution formula (10) is obtained

$\left\{\begin{array}{c}{d}_a{V}_m=2R_s{i}_{\mathrm{sa}}+R_s{i}_{\mathrm{sb}}\\ d_b{V}_m=2R_s{i}_{\mathrm{sb}}+R_s{i}_{\mathrm{sa}}\\ d_c=0\end{array}\right.---\left(12\right)$

V in formula (12) _mshould be a physical quantity with actual power direct ratio, so V _mcan pass through Active Power Filter-APF DC voltage deviation delta v _dcarry out PI adjusting, in adjustment process, both guaranteed DC voltage V _dbe stabilized in reference voltage V _drefnear remain unchanged, also obtained the required active power of whole system under present load condition.Formula (12) is Active Power Filter-APF Cycle Control at the governing equation in I region, in like manner uses similarity method can obtain the Active Power Filter-APF Cycle Control equation in II, III interval, sees respectively shown in formula (13), formula (14).

$\left\{\begin{array}{c}{d}_a=0\\ d_b{V}_m=2R_s{i}_{\mathrm{sb}}+R_s{i}_{\mathrm{sc}}\\ d_c{V}_m=2R_s{i}_{\mathrm{sc}}+R_s{i}_{\mathrm{sb}}\end{array}\right.---\left(\text{13}\right)$

$\left\{\begin{array}{c}{d}_a{V}_m=2R_s{i}_{\mathrm{sa}}+R_s{i}_{\mathrm{sc}}\\ d_b=0\\ d_c{V}_m=2R_s{i}_{\mathrm{sc}}+R_s{i}_{\mathrm{sa}}\end{array}\right.---\left(14\right)$

At I, II, III region source current i _s1, i _s2select, and abc threephase switch pipe switching logic selects to be shown in Table 3, wherein i _sa, i _sb, i _scfor the three phase mains electric current of seeing from mains side, S _arepresent that a goes up the switching signal s of brachium pontis mutually _ap, due to the complementary conducting of its upper and lower bridge arm, a descends brachium pontis to S mutually _anegate can obtain the start pulse signal s of lower brachium pontis _an, other bc are similar successively mutually, s ₁, s ₂be respectively the start pulse signal of the switching tube of rest-set flip-flop Q end output in Fig. 3.

When supply voltage vector is positioned at interval I, interval selection signal is made as 1, and other are analogized, and is mainly used in judging i in Fig. 3 _s1, i _s2selection, i.e. i _s1be to select A phase current or B phase or C phase, and in judgement Fig. 1, the triggering signal of six switching tubes is to select the Q end s of trigger 1 ₁or the Q of trigger 2 end s ₂, its system of selection is in Table 3.

Each interval parameter of the Active Power Filter-APF of table 3 Cycle Control is selected

Interval	R s.i s1	R s.i s2	S a	S b	S c
						I	R s.i sa	R s.i sb	s 1	s 2	0
II	R s.i sb	R s.i sc	0	s 1	s 2
						III	R s.i sc	R s.i sa	s 2	0	s 1

Three-phase APF system, control circuit principle as shown in Figure 3, first according to the residing interval of space vector of voltage decision condition interval selection voltage vector in table 2 and generate interval selection signal, as the selection signal of current selecting circuit and logical circuit; According to interval selection signal code, select circuit to select corresponding phase current according to table 3; The start pulse signal logic of switching tube select circuit according to interval selection signal by selecting the driving signal that each switching tube is corresponding in table 3.For example, when supply voltage vector is positioned at interval I, interval selection signal is made as 1, presses i shown in table 3 _s1select i _sa, i _s2select i _sb, logic is selected circuit now to press A in table 3 and is gone up mutually brachium pontis switching tube triggering signal S _aselect s ₁, A goes up brachium pontis S mutually _bselect s ₂, C goes up brachium pontis S mutually _cselect 0, and each phase upper and lower bridge arm is complementary, analogy when other are interval.I _sa, i _sb, i _scbe respectively ABC three-phase current.V _drefbe the reference value of controlling DC-side Voltage Stabilization, by PI, regulate and make actual DC-side Voltage Stabilization at V _dref.

By checking correctness and the feasibility of proposition control method, at MATLAB/SIMULINK, set up simulation model, it is carried out to simulation analysis.Simulation system parameters is: power line voltage 380V; Frequency 50Hz; Load is resistance inductive load; DC capacitor voltage 600V; AC inlet wire inductance 0.5mH, resistance is ignored; DC bus capacitor is 1500 μ F.

Analogue system is three-phase symmetrical system, and Fig. 4 (a) compensates front load current waveform mutually for A, and current waveform is carried out to FFT spectrum analysis, and as shown in Fig. 5 (a), electric current resultant distortion rate THD is 25.00%, well beyond national standard.Fig. 4 (b) compensates rear source current waveform mutually for A, equally current waveform is carried out to FFT spectrum analysis, as shown in Fig. 5 (b).By FFT result of spectrum analysis, can be found out, compensation after-current resultant distortion rate drops to 5.00%, has met the regulation in national standard quality of power supply utility network harmonic wave.

In recent years, along with the particularly power electronic equipment extensive use in electric power system of various nonlinear loads, Harmonious Waves in Power Systems pollution problem increases the weight of day by day.Active Power Filter-APF is the effective means that harmonic wave suppresses, and will be applied in Control Strategy for Active Power Filters based on room for improvement vector monocyclic control method, makes the whole Control System Design of Active Power Filter-APF simpler.

Shown in Fig. 3 based on room for improvement vector monocyclic control method with respect to traditional space vector monocyclic control method, space vector region selects circuit, current selecting circuit and logic to select circuit part all greatly to simplify.By A phase power source current spectrum figure before and after compensating as shown in Figure 5, can be found out, after Active Power Filter-APF compensation under this control mode, harmonic current aberration rate reduces greatly, and the source current after compensation has met the regulation in national quality of power supply utility network harmonic standard substantially.

Claims (3)

1. the room for improvement vector monocyclic control method of an Active Power Filter-APF, it is characterized in that, by means of lower array apparatus, realize: in three full control switching tubes, the emitter correspondence of each pipe is connected on the collector electrode of each pipe in other three full control switching tubes, each full control switching tube forms a brachium pontis, the tie point of aforementioned emitter and collector electrode is brachium pontis is connected mid point, the emitters of other three full control switching tubes link together and the resistance by two serial connections is connected on the collector electrodes that described three full control switching tubes link together, the emitter of each full control switching tube respectively connects the positive pole of a diode, the negative pole of diode is connected to the collector electrode of its corresponding switching tube of emitter, between the described emitter linking together and the collector electrode that links together, be provided with electric capacity, to the three-phase alternating current of nonlinear load power supply is every, by an inductance correspondence, is connected to aforementioned one respectively mutually and connects mid point, three-phase alternating current is every to be connected respectively to mutually based on space vector Cycle Control arithmetic unit, and the tie point between described two resistance is also connected on described arithmetic unit,

To be based on Cycle Control thought Active Power Filter-APF main circuit equation simplification:

$\left[\begin{array}{c}{v}_{\mathrm{sa}}\\ v_{\mathrm{sb}}\\ v_{\mathrm{sc}}\end{array}\right]=\frac{1}{3}{V}_d\left[\begin{array}{ccc}2& -1& -1\\ -1& 2& -1\\ -1& -1& 2\end{array}\right]\left[\begin{array}{c}{d}_a\\ d_b\\ d_c\end{array}\right]---\left(6\right)$

V in above formula _sa, v _sb, v _scfor three-phase alternating voltage, d _a, d _band d _cthe duty ratio that corresponds to respectively a brachium pontis above connection mid point, Vd is electric capacity both end voltage;

Condition judgment table is divided in three-phase mains voltage region

Region I II III Condition 1 v _sb-v _sc>0 v _sc-v _sa>0 v _sa-v _sb>0 Condition 2 v _sc-v _sa≤0 v _sa-v _sb≤0 v _sb-v _sc≤0

The on off states different according to triode form six fundamental space voltage vector V ₁-V ₆, between each space voltage vector, angle is 60 degree, establishes three bit digital and represents brachium pontis on off operating mode, represents conducting during for " 1 ", turn-offs first to the 3rd first to the 3rd of representing successively three-phase alternating current, six fundamental space voltage vector V for " 0 " represents ₁-V ₆arrange counterclockwise successively, the brachium pontis on off operating mode that each space voltage vector is corresponding is followed successively by (100), (110), (010), (011), (001), (101), V ₁counterclockwise to V ₃region is interval I, V ₃counterclockwise to V ₅region is interval II, V ₅counterclockwise to V ₁region is interval III, and the voltage vector of being divided condition judgment table differentiation three-phase alternating current by three-phase mains voltage region is arranged in interval I, II or III, by differentiating result, obtains the corresponding brachium pontis on off state d that goes up mutually _a, d _bor d _c, and substitution formula (6), obtain at the Active Power Filter-APF Cycle Control equation in I, II, III interval as follows successively:

$\left\{\begin{array}{c}{d}_a{V}_m=2R_s{i}_{\mathrm{sa}}+R_s{i}_{\mathrm{sb}}\\ d_b{V}_m=2R_s{i}_{\mathrm{sb}}+R_s{i}_{\mathrm{sa}}\\ d_c=0\end{array}\right.---\left(12\right)$

$\left\{\begin{array}{c}{d}_a=0\\ d_b{V}_m=2R_s{i}_{\mathrm{sb}}+R_s{i}_{\mathrm{sc}}\\ d_c{V}_m=2R_s{i}_{\mathrm{sc}}+R_s{i}_{\mathrm{sb}}\end{array}\right.---\left(13\right)$

$\left\{\begin{array}{c}{d}_a{V}_m=2R_s{i}_{\mathrm{sa}}+R_s{i}_{\mathrm{sc}}\\ d_b=0\\ d_c{V}_m=2R_s{i}_{\mathrm{sc}}+R_s{i}_{\mathrm{sa}}\end{array}\right.---\left(14\right)$

V in formula _ma physical quantity with actual power direct ratio, by Active Power Filter-APF DC voltage deviation △ v _dcarry out proportion integral control and regulate and control V _m, in adjustment process, need to guarantee DC voltage V _dremain unchanged, obtain active power required under present load condition, R _sit is sampling resistor.

2. method as claimed in claim 1, is characterized in that, by Active Power Filter-APF DC voltage deviation △ v _dcarry out proportion integral control and regulate and control V _mbe specially: by the Active Power Filter-APF Cycle Control equation in I, II, III interval and each interval parameter option table of the Active Power Filter-APF of Cycle Control, obtain current i _s1, i _s2:

Each interval parameter option table of the Active Power Filter-APF of Cycle Control

Interval R _s·i _s1 R _s·i _s2 S _a S _b S _c I R _s·i _sa R _s·i _sb s ₁ s ₂ 0 II R _s·i _sb R _s·i _sc 0 s ₁ s ₂ III R _s·i _sc R _s·i _sa s ₂ 0 s ₁

First according to the voltage vector of three-phase mains voltage region division condition distinguishing three-phase alternating current in three-phase mains voltage region division condition judgment table, be arranged in interval I, II or III and generate and select signal; According to selecting signal, according to each interval parameter option table of the Active Power Filter-APF of Cycle Control, select corresponding phase current; According to selecting each interval parameter option table of Active Power Filter-APF of signal and Cycle Control, select the switching drive signal that each triode is corresponding, S in table _arepresent that one in three-phase go up the switching signal s of brachium pontis mutually _ap, due to the complementary conducting of its upper and lower bridge arm, this descends brachium pontis to S mutually _anegate can obtain the start pulse signal s of lower brachium pontis _an, other two-phases are similar successively, s ₁, s ₂be respectively R _si _s1, R _si _s2acting in conjunction is held in two rest-set flip-flop S, the start pulse signal of the switching tube of this two trigger Q ends output.

3. the room for improvement vector Cycle Control device of an Active Power Filter-APF, it is characterized in that, comprise, in three full control switching tubes, the emitter correspondence of each pipe is connected on the collector electrode of each pipe in other three full control switching tubes, each full control switching tube forms a brachium pontis, the tie point of aforementioned emitter and collector electrode is brachium pontis is connected mid point, the emitters of other three full control switching tubes link together and the resistance by two serial connections is connected on the collector electrodes that described three full control switching tubes link together, the emitter of each full control switching tube respectively connects the positive pole of a diode, the negative pole of diode is connected to the collector electrode of its corresponding switching tube of emitter, between the described emitter linking together and the collector electrode that links together, be provided with electric capacity, to the three-phase alternating current of nonlinear load power supply is every, by an inductance correspondence, is connected to aforementioned one respectively mutually and connects mid point, three-phase alternating current is every to be connected respectively to mutually based on space vector Cycle Control arithmetic unit, tie point between described two resistance is also connected on described arithmetic unit, in addition, also comprise based on space vector Cycle Control arithmetic unit, this arithmetic unit comprises: vector interval division part, for divide the voltage vector of condition judgment table differentiation three-phase alternating current according to the room for improvement vector monocyclic control method three-phase mains voltage region of Active Power Filter-APF as claimed in claim 1, be positioned at interval I, in II or III, electric current is selected part, be used for according to three phase mains phase current, aforementioned differentiation result, form the output of two-way phase current, every road phase current is exported first amplifier on Jing Gai road successively, adder outputs to the in-phase input end of second amplifier on this road, the output of every road phase current be also connected respectively to another road phase current output in the adder of process, the output of every road the second amplifier is connected to the S end of the rest-set flip-flop on this road, Q ' the end of each rest-set flip-flop is through being connected to resetting integrator with door, capacitance voltage and reference voltage are jointly through subtracter, proportional controller outputs to resetting integrator, resetting integrator outputs to the inverting input of second amplifier on every road, clock source is connected to the R end of each rest-set flip-flop, logic selects circuit to drive signal according to the differentiation result output brachium pontis between the voltage vector location of the output of each rest-set flip-flop Q end and cross streams electricity.

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