CN104362872A - Voltage type PWM (pulse-width modulation) rectifier, and method and device for controlling voltage type PWM rectifier - Google Patents

Abstract

The invention relates to the field of power electronic technologies and nonlinear control application, and discloses a voltage type PWM (pulse-width modulation) rectifier, and a method and a device for controlling the voltage type PWM rectifier. The method includes acquiring three-phase line voltages, three-phase currents and direct-current output voltages of an alternating-current side of the rectifier; acquiring expected currents i<*>d and i<*>q and expected direct-current voltages u<*>DC of the three-phase currents in shafts d and q; controlling the rectifier according to a rectification controller under the imbalance condition of a power grid. The rectification controller is built on the basis of an EL (Euler-Lagrange) formula model. The voltage type PWM rectifier, the method and the device have the advantages that all harmonic waves in input currents of the rectifier can be eliminated or suppressed only by the aid of real-time values of the voltages and the currents, accordingly, the voltage type PWM rectifier and the device are simple in structure, and the performance can be obviously improved.

Description

The control method of voltage type PWM rectifier, device and voltage type PWM rectifier

Technical field

The present invention relates to power electronic technology and nonlinear Control application, particularly relate to a kind of control method of voltage type PWM rectifier, device and voltage type PWM rectifier.

Background technology

Voltage type PWM rectifier has the advantage of current on line side sineization, unity power factor, energy in bidirectional flow and constant dc pressure-controlled, obtains a wide range of applications in the industry.The acquisition of voltage type PWM rectifier advantage is generally under the prerequisite of hypothesis grid balance, utilizes various linear control strategies and non-linear control strategy to realize.In practical application, voltage type PWM rectifier works in non-equilibrium state, especially unbalanced source voltage, cause the existence exchanging negative-sequence current and negative sequence voltage, make will occur in alternating current will occurring even-order harmonic in odd harmonic, direct voltage, harmful effect is produced to the performance of rectifier.

Because no matter rectifier works in grid balance or non-equilibrium state, in order to improve the performance of rectifier, in prior art, propose multiple solution.Such as: one, in two-phase static α β coordinate system, electric current loop adopts the rectifier unbalance control strategy of internal mode controller, the no error following not only achieving positive-negative sequence current controls, and system can be made to obtain strong robustness.Two, in the rotation synchronous coordinate system of positive and negative, adopt double-current adjuster can avoid, into the full band filter of extraction positive and negative order components, in current regulator, adopting resonance-gain path to reduce steady-state error.Three, by the relation of voltage, electric current and power, obtain the Current Control instruction under positive-negative sequence dq coordinate system, adopt pi regulator to control.

Control strategy of the prior art have studied rectifier current control problem from different angles, controlling the rectifier with non-linear nature for adopting linear controller (as PI, ratio resonant controller, Generalized Integrator), causing rectifier control structure complexity, performance not good.For gamma controller (as active disturbance rejection, sliding moding structure) control algolithm complexity, cause computation delay; Power being controlled, there are the problems referred to above equally when using linear controller, when using wattmeter, there is switching frequency uncertain, bringing difficulty to ac filter reactor design.Problems existing is controlled for existing rectifier current.

Summary of the invention

The invention provides a kind of control method of voltage type PWM rectifier, device and voltage type PWM rectifier, solve that rectifier control structure in prior art is complicated, performance is not good, occur in input current the technical problem of harmonic wave.

The object of the invention is to be achieved through the following technical solutions:

A control method for voltage type PWM rectifier, comprising:

Obtain the three-phase line voltage u of rectifier AC _ab, u _bc, u _ca, three-phase current i _a, i _b, i _cwith VD u _dC;

Obtain the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC;

According to the commutation controller set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled, wherein, the model of described rectifier is the Mathematical Modeling under two-phase synchronous rotating frame, described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.

A control device for voltage type PWM rectifier, comprising:

First acquisition module, for obtaining the three-phase line voltage u of rectifier AC _ab, u _bc, u _ca, three-phase current i _a, i _b, i _cwith VD u _dC;

Second acquisition module, for obtaining the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC;

Control module, for the commutation controller that basis is set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled, wherein, the model of described rectifier is the Mathematical Modeling under two-phase synchronous rotating frame, and described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.

A kind of voltage type PWM rectifier, comprise rectifier and commutation controller, wherein, described commutation controller, for obtaining the three-phase line voltage u of rectifier AC _ab, u _bc, u _ca, three-phase current i _a, i _b, i _cwith VD u _dC; Obtain the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC; According to the commutation controller set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled, wherein, the model of described rectifier is the Mathematical Modeling under two-phase synchronous rotating frame, described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.

By the control method of a kind of voltage type PWM rectifier provided by the invention, device and voltage type PWM rectifier, by obtaining the three-phase line voltage of rectifier AC, three-phase current and VD, obtain the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC, according to the commutation controller set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled.Make the instantaneous value only needing voltage, electric current, just can eliminate or suppress all harmonic waves in rectifier input current, structure is simple, performance boost is obvious.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, also can obtain other accompanying drawing according to these accompanying drawings.

The voltage type PWM rectifier main circuit structure figure that Fig. 1 provides for the embodiment of the present invention;

The flow chart of the control method of a kind of voltage type PWM rectifier that Fig. 2 provides for the embodiment of the present invention;

The Establishing process figure of the commutation controller that Fig. 3 provides for the embodiment of the present invention;

The structural representation of the control device of a kind of voltage type PWM rectifier that Fig. 4 provides for the embodiment of the present invention;

The structural representation of a kind of voltage type PWM rectifier that Fig. 5 provides for the embodiment of the present invention.

Embodiment

For enabling above-mentioned purpose of the present invention, feature and advantage become apparent more, and below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation.

If Fig. 1 is for providing voltage type PWM rectifier main circuit structure figure in the embodiment of the present invention, in, the break-even situation of switching device identical in hypothesis net side filter parameter, Three-phase PWM Voltage Rectifier main circuit as shown in Figure 1.When unbalanced power supply, three-phase phase voltage u _a+ u _b+ u _c≠ 0; Electric current meets i _a+ i _b+ i _c=0; S _a+ S _b+ S _c≠ 0 (S _a, S _b, S _cfor the driving switch function of every phase brachium pontis, S _i=1 represents upper brachium pontis conducting, and lower brachium pontis turns off; S _i=0 represents that upper brachium pontis turns off, lower brachium pontis conducting; I=a, b, c).The rectifier Mathematical Modeling that line voltage, wiretap amount, alternating current and direct voltage are variable can be obtained by Fig. 1, as follows:

$\left\{\begin{array}{c}3L\frac{{\mathrm{di}}_a}{\mathrm{dt}}=(u_{\mathrm{ab}}-u_{\mathrm{ca}})-3{\mathrm{Ri}}_a-(S_{\mathrm{ab}}-S_{\mathrm{ca}})u_{\mathrm{DC}}\\ 3L\frac{{\mathrm{di}}_b}{\mathrm{dt}}=(u_{\mathrm{bc}}-u_{\mathrm{ab}})-3{\mathrm{Ri}}_b-(S_{\mathrm{bc}}-S_{\mathrm{ab}})u_{\mathrm{DC}}\\ 3L\frac{{\mathrm{di}}_c}{\mathrm{dt}}=(u_{\mathrm{ca}}-u_{\mathrm{bc}})-3{\mathrm{Ri}}_c-(S_{\mathrm{ca}}-S_{\mathrm{bc}})u_{\mathrm{DC}}\\ C\frac{{\mathrm{du}}_{\mathrm{DC}}}{\mathrm{dt}}=\frac{1}{3}[(S_{\mathrm{ab}}-S_{\mathrm{ca}})i_a+(S_{\mathrm{bc}}-S_{\mathrm{ab}})i_b+(S_{\mathrm{ca}}-S_{\mathrm{bc}})i_c]-\frac{u_{\mathrm{DC}}}{R_L}\end{array}\right.---\left(1\right)$

S _ab, S _bc, S _cafor wiretap function, S _ab=S _a-S _b, S _bc=S _b-S _c, S _ca=S _c-S _a, u _ab, u _bc, u _cafor grid line voltage, three-phase current is i _a, i _b, i _c, u _dCfor VD.

Based on the application scenarios shown in Fig. 1, for the control to driving switch function, introduce the control method of a kind of voltage type PWM rectifier provided in the embodiment of the present invention, as shown in Figure 2, the method comprises the steps:

Step 201, the three-phase line voltage obtaining rectifier AC, three-phase current and VD;

Wherein, voltage sensor can be utilized to obtain the three-phase line voltage u of rectifier AC _ab, u _bc, u _cawith VD u _dC, utilize current sensor to obtain three-phase current i _a, i _b, i _c;

Step 202, obtain the expectation electric current of three-phase current under two-phase synchronous rotating frame and expect direct voltage;

Wherein, i ^* _d, i ^* _qfor the expectation electric current under two-phase synchronous rotating frame, direct voltage equals given voltage the requirement expected is i ^* _d=I _m(amplitude for symmetrical alternating current phase current during steady operation), i ^* _q=0, u ^* _dCfor steady state value.U ^* _dCmeet load request and (U _mamplitude for grid balance ac phase voltage) determine.According to alternating current-direct current side power-balance (ignoring switching losses), I _mcalculating formula be u ^* _dCthe VD expected, R is filter resistor, R _lfor Equivalent DC load, u _ldfor the line voltage under two-phase synchronous rotating frame.

The commutation controller that step 203, basis are set up based on EL equation model, in unbalanced power supply situation, controls described rectifier.

Wherein, the model of described rectifier is the Mathematical Modeling under two-phase synchronous rotating frame, and described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.

Embodiments providing a kind of control method of voltage type PWM rectifier, by obtaining the three-phase line voltage of rectifier AC, three-phase current and VD, obtaining the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC, according to the commutation controller set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled.Make the instantaneous value only needing voltage, electric current, just can eliminate or suppress all harmonic waves in rectifier input current, structure is simple, performance boost is obvious.

Before the step 201 of the embodiment of the present invention, need to set up commutation controller in advance, below to the process of establishing of commutation controller, describe in detail, be illustrated in figure 3 the Establishing process figure of commutation controller, comprise the steps:

Step 301, triple line current i to described rectifier AC _a, i _b, i _ccarry out Park conversion, to obtain the ac-side current i under two-phase synchronous rotating frame _d, i _q;

Wherein, according to matrix formula (2), to i _a, i _b, i _ccarry out Park conversion, to obtain the ac-side current i under two-phase synchronous rotating frame _d, i _q,

Step 302, to the wiretap function S of described rectifier under three-phase static coordinate system _ab, S _bc, S _cawith three-phase line voltage u _ab, u _bc, u _cacarry out Park conversion, to obtain the switch function S under two-phase synchronous rotating frame _ld, S _lqwith AC voltage u _ld, u _lq;

Wherein, according to matrix formula (3), to switch function S _ab, S _bc, S _cawith three-phase line voltage u _ab, u _bc, u _cacarry out Park conversion, to obtain the switch function S under two-phase synchronous rotating frame _ld, S _lqwith AC voltage u _ld, u _lq.

Wherein, sequencing is not had between step 301-302.

Step 303, by i _d, i _q, u _ld, u _lq, S _ld, S _lqsubstitute into the Mathematical Modeling of described rectifier under three-phase static coordinate system, to obtain the Mathematical Modeling of described rectifier under two-phase synchronous rotating frame;

Wherein, by i _d, i _q, u _ld, u _lq, S _ld, S _lqsubstitute in formula (1), obtain the Mathematical Modeling of described rectifier under two-phase synchronous rotating frame $\left\{\begin{array}{c}L\frac{{\mathrm{di}}_d}{\mathrm{dt}}=\frac{\sqrt{3}}{3}{u}_{\mathrm{ld}}-{\mathrm{Ri}}_d+L{\mathrm{\&omega;i}}_q-\frac{\sqrt{3}}{3}{S}_{\mathrm{ld}}{u}_{\mathrm{DC}}\\ L\frac{{\mathrm{di}}_q}{\mathrm{dt}}=\frac{\sqrt{3}}{3}{u}_{\mathrm{lq}}-{\mathrm{Ri}}_q-L{\mathrm{\&omega;i}}_d-\frac{\sqrt{3}}{3}{S}_{\mathrm{lq}}{u}_{\mathrm{DC}}\\ \frac{2}{3}C\frac{{\mathrm{du}}_{\mathrm{DC}}}{\mathrm{dt}}=\frac{\sqrt{3}}{3}(S_{\mathrm{ld}}{i}_d+S_{\mathrm{lq}}{i}_q)-\frac{2}{3}\frac{u_{\mathrm{DC}}}{R_L}\end{array}\right.---\left(4\right),$ In formula (4), i _d, i _qfor the component of alternating current on d, q axle; S _ld, S _lqfor the component of wiretap function on d, q axle; u _ld, u _lqfor the component of grid line voltage on d, q axle.

Step 304, according to EL equation model and described rectifier commutation controller described in the Mathematical Models under two-phase synchronous rotating frame.

Wherein, step 405 is in order to obtain based on EL equation (Euler-Lagrange, Euler-Lagrange equation) rectifier Passive Shape Control strategy, need according to EL equation model and described rectifier the Mathematical Models commutation controller under two-phase synchronous rotating frame, specifically comprise the steps:

Step 305-1, be EL equation model by the Transformation of Mathematical Model of described rectifier under two-phase synchronous rotating frame;

Wherein, formula (4) is transformed into EL model in formula (5) represent that x is to the derivative of time, $x=\left(\begin{array}{c}{x}_1\\ x_2\\ x_3\end{array}\right)=\left(\begin{array}{c}{i}_d\\ i_q\\ u_{\mathrm{DC}}\end{array}\right),$ $M=\left(\begin{array}{ccc}L& 0& 0\\ 0& L& 0\\ 0& 0& 2C/3\end{array}\right),$ $J=\left(\begin{array}{ccc}0& -\mathrm{\&omega;L}& \sqrt{3}{S}_{\mathrm{ld}}/3\\ \mathrm{\&omega;L}& 0& \sqrt{3}{S}_{\mathrm{lq}}/3\\ -\sqrt{3}{S}_{\mathrm{ld}}/3& -\sqrt{3}{S}_{\mathrm{lq}}/3& 0\end{array}\right)$ For antisymmetric matrix, $R=\left(\begin{array}{ccc}R& 0& 0\\ 0& R& 0\\ 0& 0& 2/3R_L\end{array}\right),$ $u=\left(\begin{array}{c}\sqrt{3}{u}_{\mathrm{ld}}/3\\ \sqrt{3}{u}_{\mathrm{lq}}/3\\ 0\end{array}\right).$

Step 305-2, in EL equation model, inject damping, to obtain the control law of described commutation controller;

Wherein, if rectifier expects that current phasor is x ^*, error current vector x _e=x-x ^*.Formula (5) becomes $M{\stackrel{\&CenterDot;}{x}}_e+R_d{x}_e=u-(M{\stackrel{\&CenterDot;}{x}}^{*}+\mathrm{Jx}+R{x}^{*}-R_a{x}_e)$ Formula (6), error energy function is passive Shape Control utensil based on EL equation has good steady-state behaviour, but convergence rate is comparatively slow, for accelerating system convergence speed, injecting damping in the controller, making the quick vanishing of error energy function, adopts damping to inject R _dx _e=(R+R _a) x _e, R _afor matrix is injected in damping, $R_a=\left(\begin{array}{ccc}{r}_{a1}& 0& 0\\ 0& r_{a2}& 0\\ 0& 0& 2/3r_{a3}\end{array}\right),$ R _a1, r _a2, r _a3for the normal number that can set, when introducing damping and injecting matrix, formula (6) becomes $M{\stackrel{\&CenterDot;}{x}}_e=u-(M{\stackrel{\&CenterDot;}{x}}^{*}+\mathrm{Jx}+R{x}^{*}-R_a{x}_e)-R_d{x}_e,$ Energy error function is got and leads ${\stackrel{\&CenterDot;}{H}}_e=\left(x\right)=x_e^{T}M{\stackrel{\&CenterDot;}{x}}_e,$ ${\stackrel{\&CenterDot;}{H}}_e\left(x\right)=x_e^T(u-(M{\stackrel{\&CenterDot;}{x}}^{*}+\mathrm{Jx}+R{x}^{*}-R_a{x}_e)-R_d{x}_e),$ The control law of controller is made to be formula (7), the then derivative of energy error function against time make H _e(x) → 0, x → x ^*, under formula (7) effect, rectifier can realize control objectives, regulates R _awith regard to adjustable H _e(x) converge to 0 speed.The wiretap function of control objectives can be realized by formula (7)

$S_{\mathrm{ld}}=(\sqrt{3}{u}_{\mathrm{ld}}-3L{\stackrel{\&CenterDot;}{i}}_d^{*}+3\mathrm{\&omega;}{\mathrm{Li}}_q-3{\mathrm{Ri}}_d^{*}+3r_{\mathrm{al}}(i_d-i_d^{*}))/\sqrt{3}{u}_{\mathrm{DC}},$

$S_{\mathrm{lq}}=(\sqrt{3}{u}_{\mathrm{lq}}-3\mathrm{\&omega;}{\mathrm{Li}}_d+3r_{a2}{i}_q)/\sqrt{3}{u}_{\mathrm{DC}};$ Formula (8), r _a1, r _a2for the damping of injecting, for i _ddesired value.Three-phase PWM Voltage Rectifier is in unbalanced power supply situation during steady operation, and current on line side is sinusoidal, expectation power factor is 1, and direct voltage equals given voltage then (I _mamplitude for symmetrical alternating current phase current during steady operation)

$I_m=\frac{1}{2}(\frac{u_{\mathrm{ld}}}{\sqrt{3}R}-\sqrt{\frac{{\left(\sqrt{3}{u}_{\mathrm{ld}}\right)}^2}{{\left(3R\right)}^2}-\frac{8u_{\mathrm{DC}}^{*}}{3{\mathrm{RR}}_L}})---\left(9\right)$

Step 305-3, control law according to described commutation controller, set up commutation controller.

Wherein, the output of described commutation controller is switch function Sa, Sb, Sc,

$\left\{\begin{array}{c}{S}_a=\frac{1}{3}(S_{\mathrm{ab}}-S_{\mathrm{ca}}+\mathrm{\&Delta;S})\\ S_b=\frac{1}{3}(S_{\mathrm{bc}}-S_{\mathrm{ab}}+\mathrm{\&Delta;S})\\ S_c=\frac{1}{3}(S_{\mathrm{ca}}-S_{\mathrm{bc}}+\mathrm{\&Delta;S})\end{array}\right.$ Formula (10), Δ S=S _a+ S _b+ S _c, wherein, first pass through S _ldand S _lqcarry out the inverse transformation of dq0 to abc, obtain wiretap function Sab, Sbc, Sca under three-phase static coordinate system,

S _ab＝S _ldsin(ωt+30°)+S _lqcos(ωt+30°)，S _bc＝S _ldsin(ωt-90°)+S _lqcos(ωt-90°)，

S _ca=S _ldsin (ω t+150 °)+S _lqcos (ω t+150 °), S _ab, S _bc, S _caby S _ldand S _lqcarry out the inverse transformation of dq0 to abc and obtain, formula (10) being updated in formula (1), obtaining $\left\{\begin{array}{c}{u}_a={\mathrm{Ri}}_a+L\frac{{\mathrm{di}}_a}{\mathrm{dt}}+S_a{u}_{\mathrm{DC}}+\frac{1}{3}(\mathrm{\&Delta;u}-\mathrm{\&Delta;}{\mathrm{Su}}_{\mathrm{DC}})\\ u_b={\mathrm{Ri}}_b+L\frac{{\mathrm{di}}_b}{\mathrm{dt}}+S_b{u}_{\mathrm{DC}}+\frac{1}{3}(\mathrm{\&Delta;u}-\mathrm{\&Delta;}{\mathrm{Su}}_{\mathrm{DC}})\\ u_c={\mathrm{Ri}}_c+L\frac{{\mathrm{di}}_c}{\mathrm{dt}}+S_c{u}_{\mathrm{DC}}+\frac{1}{3}(\mathrm{\&Delta;u}-\mathrm{\&Delta;}{\mathrm{Su}}_{\mathrm{DC}})\end{array}\right.$ Formula (11), in formula, Δ u=u _a+ u _b+ u _c.

For overcoming the impact of Δ u on alternating current, according to formula (10), can select then have $\left\{\begin{array}{c}{u}_a={\mathrm{Ri}}_a+L\frac{{\mathrm{di}}_a}{\mathrm{dt}}+S_a{u}_{\mathrm{DC}}\\ u_b={\mathrm{Ri}}_b+L\frac{{\mathrm{di}}_b}{\mathrm{dt}}+S_b{u}_{\mathrm{DC}}\\ u_c={\mathrm{Ri}}_c+L\frac{{\mathrm{di}}_c}{\mathrm{dt}}+S_c{u}_{\mathrm{DC}}\end{array}\right.$ Formula (12).

The pwm signal obtained by formula (12) can realize when unbalanced power supply, when passive electrical stream controller ensures that alternating current is sinusoidal, unbalanced source voltage must cause the imbalance of switch function, i.e. the imbalance of the imbalance compensation line voltage of rectifier input voltage.

Embodiments provide a kind of control device of voltage type PWM rectifier, as shown in Figure 4, comprising:

First acquisition module 410, for obtaining the three-phase line voltage u of rectifier AC _ab, u _bc, u _ca, three-phase current i _a, i _b, i _cwith VD u _dC;

Second acquisition module 420, for obtaining the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC;

Control module 430, for the commutation controller that basis is set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled, wherein, the model of described rectifier is the Mathematical Modeling under three-phase static coordinate system, and described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.

Wherein, described control module, comprising:

First converter unit 431, for the triple line current i of the rectifier AC by described first acquisition module acquisition _a, i _b, i _cbe transformed to the ac-side current i under two-phase synchronous rotating frame _d, i _q;

Second converter unit 432, for the three-phase line voltage u of the rectifier AC by described first acquisition module acquisition _ab, u _bc, u _cabe transformed to the AC voltage u under two-phase synchronous rotating frame _ld, u _lq;

Damping input unit 433, for inputting damping r _a1, r _a2;

Current calculation unit 434, for according to the line voltage u under two-phase synchronous rotating frame _ld, Equivalent DC load, input resistance R, expectation VD u ^* _dC, the expectation current i under two-phase synchronous rotating frame ^* _q;

Processing and control element (PCE) 435, for according to i _d, i _q, u _ld, u _lq, r _a1, r _a2, u _dC, calculate wiretap function Sab, Sbc, Sca, according to described wiretap function Sab, Sbc, Sca, calculate switch function Sa, Sb, Sc, and by described switch function Sa, Sb, Sc, in unbalanced power supply situation, described rectifier is controlled.

Wherein, described processing and control element (PCE) 435, comprising:

Computation subunit 4351, for according to i _d, i _q, u _ld, u _lq, r _a1, r _a2, u _dC, calculate the wiretap function under two-phase synchronous rotating frame

$S_{\mathrm{ld}}=(\sqrt{3}{u}_{\mathrm{ld}}-3L{\stackrel{\&CenterDot;}{i}}_d^{*}+3\mathrm{\&omega;}{\mathrm{Li}}_q-3{\mathrm{Ri}}_d^{*}+3r_{\mathrm{al}}(i_d-i_d^{*}))/\sqrt{3}{u}_{\mathrm{DC}},$

control to export subelement 4352, for S _ldand S _lqcarry out Park inverse transformation, to obtain wiretap function Sab, Sbc, the Sca under three-phase static coordinate system;

Control to perform subelement 4353, for according to wiretap function Sab, Sbc, Sca, calculate switch function Sa, Sb, Sc, and by described switch function Sa, Sb, Sc, in unbalanced power supply situation, described rectifier is controlled.

Additionally provide a kind of voltage type PWM rectifier in the embodiment of the present invention, as shown in Figure 5, comprise rectifier 510 and commutation controller 520, wherein, described commutation controller 520, for obtaining the three-phase line voltage u of rectifier AC _ab, u _bc, u _ca, three-phase current i _a, i _b, i _cwith VD u _dC; Obtain the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC; According to the commutation controller set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled, wherein, the model of described rectifier is the Mathematical Modeling under three-phase static coordinate system, described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.

Through the above description of the embodiments, those skilled in the art can be well understood to the mode that the present invention can add required hardware platform by software and realize, can certainly all be implemented by hardware, but in a lot of situation, the former is better execution mode.Based on such understanding, what technical scheme of the present invention contributed to background technology can embody with the form of software product in whole or in part, this computer software product can be stored in storage medium, as ROM/RAM, magnetic disc, CD etc., comprising some instructions in order to make a computer equipment (can be personal computer, server, or the network equipment etc.) perform the method described in some part of each embodiment of the present invention or embodiment.

Above to invention has been detailed introduction, applying specific case herein and setting forth principle of the present invention and execution mode, the explanation of above embodiment just understands method of the present invention and core concept thereof for helping; Meanwhile, for one of ordinary skill in the art, according to thought of the present invention, all will change in specific embodiments and applications, in sum, this description should not be construed as limitation of the present invention.

Claims (7)

1. a control method for voltage type PWM rectifier, is characterized in that, comprising:

Obtain the three-phase line voltage u of rectifier AC _ab, u _bc, u _ca, three-phase current i _a, i _b, i _cwith VD u _dC;

Obtain the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC;

According to the commutation controller set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled, wherein, the model of described rectifier is the Mathematical Modeling under two-phase synchronous rotating frame, described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.

2. method according to claim 1, is characterized in that, according to the commutation controller set up based on EL equation model, comprising:

To the triple line current i of described rectifier AC _a, i _b, i _ccarry out Park conversion, to obtain the ac-side current i under two-phase synchronous rotating frame _d, i _q;

To the wiretap function S of described rectifier under three-phase static coordinate system _ab, S _bc, S _cawith three-phase line voltage u _ab, u _bc, u _cacarry out Park conversion, to obtain the switch function S under two-phase synchronous rotating frame _ld, S _lqwith AC voltage u _ld, u _lq;

To the three-phase line voltage u of described rectifier AC _ab, u _bc, u _caconvert, to obtain the AC voltage u under two-phase synchronous rotating frame _ld, u _lq;

By i _d, i _q, u _ld, u _lq, S _ld, S _lqsubstitute into the Mathematical Modeling of described rectifier under three-phase static coordinate system, to obtain the Mathematical Modeling of described rectifier under two-phase synchronous rotating frame;

The commutation controller described in the Mathematical Models under two-phase synchronous rotating frame according to EL equation model and described rectifier.

3. method according to claim 2, is characterized in that, described according to EL equation model and described rectifier commutation controller described in the Mathematical Models under two-phase synchronous rotating frame, comprising:

Be EL equation model by the Transformation of Mathematical Model of described rectifier under two-phase synchronous rotating frame;

Damping is injected, to obtain the control law of described commutation controller in EL equation model;

According to the control law of described commutation controller, set up commutation controller, the output of described commutation controller

S _a＝(1/3)*(S _ab-S _ca+ΔS)、

S _b＝(1/3)*(S _bc-S _ab+ΔS)、

S _c＝(1/3)*(S _ca-S _bc+ΔS)，ΔS＝S _a+S _b+S _c，

Wherein,

S _ab＝S _ldsin(ωt+30°)+S _lqcos(ωt+30°)，

S _bc＝S _ldsin(ωt-90°)+S _lqcos(ωt-90°)，

S _ca＝S _ldsin(ωt+150°)+S _lqcos(ωt+150°)，

$S_{\mathrm{ld}}=(\sqrt{3}{u}_{\mathrm{ld}}-3L{\stackrel{\&CenterDot;}{i}}_d^{*}+{3\mathrm{\&omega;Li}}_q-{3\mathrm{Ri}}_d^{*}+{3r}_{a1}(i_d-i_d^{*}))/\sqrt{3}{u}_{\mathrm{DC}},$

$S_{\mathrm{lq}}=(\sqrt{3}{u}_{\mathrm{lq}}-{3\mathrm{\&omega;Li}}_d+{3r}_{a2}{i}_q)/\sqrt{3}{u}_{\mathrm{DC}},$ R _a1, r _a2for the damping of injecting, for i _ddesired value.

4. a control device for voltage type PWM rectifier, is characterized in that, comprising:

First acquisition module, for obtaining the three-phase line voltage u of rectifier AC _ab, u _bc, u _ca, three-phase current i _a, i _b, i _cwith VD u _dC;

Second acquisition module, for obtaining the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC;

Control module, for the commutation controller that basis is set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled, wherein, the model of described rectifier is the Mathematical Modeling under two-phase synchronous rotating frame, and described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.

5. device according to claim 4, is characterized in that, described control module, comprising:

First converter unit, for the triple line current i of the rectifier AC by described first acquisition module acquisition _a, i _b, i _cbe transformed to the ac-side current i under two-phase synchronous rotating frame _d, i _q;

Second converter unit, for the three-phase line voltage u of the rectifier AC by described first acquisition module acquisition _ab, u _bc, u _cabe transformed to the AC voltage u under two-phase synchronous rotating frame _ld, u _lq;

Damping input unit, for inputting damping r _a1, r _a2;

Current calculation unit, for according to the line voltage u under two-phase synchronous rotating frame _ld, DC load, filter resistor R, expectation VD u ^* _dC, the expectation current i under two-phase synchronous rotating frame ^* _d;

Processing and control element (PCE), for according to i _d, i _q, u _ld, u _lq, r _a1, r _a2, u _dC, calculate wiretap function Sab, Sbc, Sca, according to described wiretap function Sab, Sbc, Sca, calculate switch function Sa, Sb, Sc, and by described switch function Sa, Sb, Sc, in unbalanced power supply situation, described rectifier is controlled.

6. device according to claim 5, is characterized in that, described processing and control element (PCE), comprising:

Computation subunit, for according to i _d, i _q, u _ld, u _lq, r _a1, r _a2, u _dC, calculate the wiretap function under two-phase synchronous rotating frame $S_{\mathrm{ld}}=(\sqrt{3}{u}_{\mathrm{ld}}-3L{\stackrel{\&CenterDot;}{i}}_d^{*}+{3\mathrm{\&omega;Li}}_q-{3\mathrm{Ri}}_d^{*}+{3r}_{a1}(i_d-i_d^{*}))/\sqrt{3}{u}_{\mathrm{DC}},$ $S_{\mathrm{lq}}=(\sqrt{3}{u}_{\mathrm{lq}}-{3\mathrm{\&omega;Li}}_d+{3r}_{a2}{i}_q)/\sqrt{3}{u}_{\mathrm{DC}};$

Control to export subelement, for S _ldand S _lqcarry out Park inverse transformation, to obtain wiretap function Sab, Sbc, the Sca under three-phase static coordinate system;

Control to perform subelement, for according to wiretap function Sab, Sbc, Sca, calculate switch function Sa, Sb, Sc, and by described switch function Sa, Sb, Sc, in unbalanced power supply situation, described rectifier is controlled.

7. a voltage type PWM rectifier, is characterized in that, comprises rectifier and commutation controller, and wherein, described commutation controller, for obtaining the three-phase line voltage u of rectifier AC _ab, u _bc, u _ca, three-phase current i _a, i _b, i _cwith VD u _dC; Obtain the expectation current i of three-phase current at dq axle ^* _d, i ^* _qwith expectation direct voltage u ^* _dC; According to the commutation controller set up based on EL equation model, in unbalanced power supply situation, described rectifier is controlled, wherein, the model of described rectifier is the Mathematical Modeling under two-phase synchronous rotating frame, described commutation controller is the Passive Shape Control device based on EL equation model, described commutation controller be input as u _ab, u _bc, u _ca, i _a, i _b, i _c, i ^* _d, the output of described commutation controller is switch function Sa, Sb, Sc under three-phase static coordinate system.