CN102868309A - PWM (Pulse-Width Modulation) rectifier controlling method and PWM rectifier - Google Patents

Abstract

The embodiment of the invention provides a PWM (Pulse-Width Modulation) rectifier controlling method and a PWM rectifier. The PWM rectifier controlling method is a passivity control method based on repeated control and compensation, and comprises the following steps: a control law of the PWM rectifier based on the interconnection and damping configuration of port controlled dissipation Hamilton models is obtained with a Lagrange-Charpy integral method; and a composite controller including repeated control and passive control is used as a controller of the PWM rectifier, and the passive control is compensated by the repeated control according to the control law so as to suppress periodic interference. According to the embodiment of the invention, PWM rectification of a unit power factor can be realized, and at the same time the harmonic interference of a power grid is better suppressed under the condition of not detecting load harmonic current so as to improve power quality. Compared with the conventional PWM rectifier, the PWM rectifier disclosed by the invention has the functions of harmonic suppression and reactive compensation under the condition of not increasing hardware cost.

Description

A kind of pulse width modulation (PWM) Rectifier and PWM rectifier

Technical field

The present invention relates to technical field of power systems, relate in particular to a kind of PWM(Pulse Width Modulation, pulse width modulation) Rectifier and PWM rectifier.

Background technology

Desirable electric power system provides reliable and stable electric energy to the user incessantly with the standard sine wave of rated voltage and constant frequency (50Hz or 60Hz).Needs along with development and the production of industrial technology, the particularly nearly for decades development of power electronic technology, the electric energy major part that electric power system provides is all passed through the power electronic technology quadratic transformation and is offered later on the power consumption equipment use again, make electric energy obtain utilizing more fully, improved widely efficient and the comfortableness of human being's production and life.But the non-linear and time variation of power electronic equipment own is so that the serious distortion that the voltage waveform of electric power system occurs has become topmost harmonic source in the electric power system, and its harm that brings has caused people's extensive concern.On the other hand, particularly the IT industry of develop rapidly is more and more stricter to the requirement of the quality of power supply by the automatic industry production line of the control of computer technology and microelectric technique, any power quality problem all may cause the interruption of producing or the infringement of equipment, have a strong impact on factory and normally produce, bring huge economic loss to the user.Therefore, extremely urgent to the research that improves the quality of power supply, how to suppress mains by harmonics, improve the quality of power supply and become in recent years study hotspot.Present countermeasure mainly contains two kinds: the one, itself transform producing harmonic wave and the idle rectifier of not controlling rectification and phase control rectifier; The 2nd, in electric power system, load harmonic and reactive power compensator.

In first method, at the application scenario of smaller power below several kilowatts normal operation power factor calibrating method (Power Factor Correction, PFC); Large-power occasions normal operation multiple technology more than hundreds of kilowatt.And the widely used several kilowatts of power occasions to hundreds of kilowatt in the industry, the PWM rectifier is because having following advantage: it is little to have an AC harmonic current, unity power factor, energy in bidirectional flow, can realize the constant voltage Current Control, thereby attract wide attention, it has begun to begin to use in a part of occasion now, but also there is following shortcoming in conventional P WM rectifier: can only make rectifier and load equivalent thereof by control is a linear load, guarantee that flowing into the PWM rectifier current is unity power factor, the harmonic problem that other nonlinear loads in the electrical network are brought can't suppress; Function singleness causes that its cost performance is not high have been hindered it and apply on a large scale.

In the second approach, at present Passive LC (inductance capacitance) tuned filter use is the most extensive, but an important trend adopts Active Power Filter-APF (Active Power Filter, APF) exactly.Active Power Filter-APF also is a kind of power electronic equipment.Its basic principle is to detect harmonic current from target compensation, produce one with this harmonic current equal and opposite in direction and opposite polarity offset current by compensation arrangement, thereby making power network current only contain fundametal compoment (in electric power system, is frequency that voltage or the electric current of 50Hz sine wave calls fundamental voltage or electric current.Frequency is that the waveform of 50Hz integral multiple is called high order harmonic component, is called for short harmonic wave).Basic principle according to Active Power Filter-APF, need first the harmonic wave in the load current and reactive current to be extracted, controller sends with the system harmonics size of current according to the reference harmonic Current Control and equates, the harmonic current injection of opposite direction is offset harmonic wave and reactive current in system.Because the object of Active Power Filter-APF compensation is high order harmonic component, cause present Active Power Filter-APF in control, to exist much being difficult to the problem that overcomes:

(1) high accuracy, real-time harmonic current test problems.In the active filter control method, need to detect in real time the harmonic current of nonlinear load.Since the Active Power Filter-APF object that need to compensate be dynamic change very the harmonic current of nonlinear load generation soon, so harmonic detecting system must can be accurately and is detected fast the harmonic current of system.Because the frequency domain detection method based on Fourier transform is too complicated, too high to hardware requirement, real-time can't guarantee under present level of hardware.The Harmonic Detecting Algorithm of present most widely used being based on " instantaneous reactive power theory ".But this kind method will be used low pass filter in the middle of the harmonic wave leaching process, and the harmonic reference signal that low pass filter can cause detecting has certain time-delay, affects compensation effect.

(2) reference harmonic current tracking problem.The control strategy of Active Power Filter-APF is the critical technology that guarantees its compensation performance.Because the Active Power Filter-APF target compensation is once to arrive the idle and harmonic current that does not repeatedly wait, therefore need controller that enough electric current bandwidth are arranged, the dynamic change of the various non-linear power electronics load in the simultaneously electric power system is difficult to precognition, cause the number of times of harmonic current and the size variation of compensation of active filter needs variable, therefore, selecting a more perfect high performance controller is a relatively stern challenge to scientific research and engineering staff.

(3) Cost Problems of compensation harmonic equipment.Basic principle according to active filter, in order to guarantee its normal operation, not only need to detect in real time the threephase load harmonic current as a reference, and need to detect in real time the three-phase offset current of Active Power Filter-APF as the controller feed back input, therefore need the sensor device of a large amount of high-speed, high precisions and signal conditioning circuit and the powerful processor of computing capability of high-speed, high precision, a large amount of high-power electric and electronics of adding itself are controlled device entirely, so price comparison is expensive.

As fully visible, the PWM rectifier can only be realized self unit power factor rectifier on (1) present traditional sense, but does not possess the function that mains by harmonics that other loads in the electrical network are caused suppresses.(2) equipment that at present mains by harmonics is suppressed comprises that all there are certain shortcoming in passive filter and active filter.

Summary of the invention

The embodiment of the invention provides a kind of pulse width modulation (PWM) Rectifier and PWM rectifier, suppress preferably the mains by harmonics interference in the situation that do not detect load harmonic current when can realize unity power factor PWM rectification, to improve the quality of power supply.

On the one hand, the embodiment of the invention provides a kind of pulse width modulation (PWM) Rectifier, and described PWM Rectifier is that the method comprises based on the passivity control method that repeats control and compensation:

Obtain the control law based on the interconnected and damping of Port-Controlled dissipation Hamilton model configuration of PWM rectifier by Lagrange-Xia Bi integration method;

With repeating to control the composite controller that forms with the Passive Shape Control controller as the PWM rectifier, according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed.

Optionally, in an embodiment of the present invention, describedly will repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprise: will repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, under the effect of repeating signal generator, by the Cycle by Cycle compensation to the waveform error of the Passive Shape Control signal of described PWM rectifier, meritorious to realize first-harmonic when the stable state, or idle, or higher harmonic current disturbs, or the PERIODIC INTERFERENCE that " dead time effect " brings suppresses.

Optionally, in an embodiment of the present invention, described according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprise: when PWM rectifier DC side does not have other non-linear or reactive loads after the point of common coupling during with load and in the electrical network, the PWM rectifier is placed the PWM rectification state, utilize described passivity control method based on repeating control and compensation to make the power network current before the point of common coupling be unity power factor; Perhaps, when only having reactive load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the reactive power compensation state, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send reactive current electrical network is carried out reactive power compensation; Perhaps, when only having nonlinear load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the harmonic wave holddown, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, the harmonic current of opposite direction suppresses the mains by harmonics electric current.

Optionally, in an embodiment of the present invention, described according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprise: when existing nonlinear load has reactive load again after the point of common coupling in the zero load of PWM rectifier and the electrical network, place harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, utilizing described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current equates, the harmonic current of opposite direction and reactive current suppress and reactive power compensation electrical network is carried out harmonic current; Perhaps, when PWM rectifier DC side has reactive load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and reactive power compensation state, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, electric network reactive-load is compensated; Perhaps, when PWM rectifier DC side has nonlinear load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and harmonic wave holddown, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, the mains by harmonics electric current is suppressed.

Optionally, in an embodiment of the present invention, described according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprise: when PWM rectifier DC side when existing nonlinear load has reactive load again after the point of common coupling in load and electrical network, place PWM rectification and harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, send harmonic current and the reactive current opposite with mains by harmonics size of current equal direction, suppress and reactive power compensation electrical network is carried out harmonic current.

On the other hand, the embodiment of the invention provides a kind of PWM rectifier, and described PWM rectifier is controlled based on the passivity control method that repeats control and compensation, and described PWM rectifier comprises:

Controller is used for obtaining the control law that the interconnected and damping based on Port-Controlled dissipation Hamilton model of PWM rectifier configures by Lagrange-Xia Bi integration method; With repeating to control the composite controller that forms with the Passive Shape Control controller as the PWM rectifier, according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed.

Optionally, in an embodiment of the present invention, described controller, concrete be used for to repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, under the effect of repeating signal generator, by the Cycle by Cycle compensation to the waveform error of the Passive Shape Control signal of described PWM rectifier, to realize PERIODIC INTERFERENCE inhibition meritorious or idle to first-harmonic or that higher harmonic current disturbs or " dead time effect " brings when the stable state.

Optionally, in an embodiment of the present invention, described controller, further concrete being used for when PWM rectifier DC side during with load and electrical network point of common coupling when not having afterwards other non-linear or reactive loads, the PWM rectifier is placed the PWM rectification state, utilize described passivity control method based on repeating control and compensation to make point of common coupling power network current before be unity power factor; Perhaps, when only having reactive load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the reactive power compensation state, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send reactive current electrical network is carried out reactive power compensation; Perhaps, when only having nonlinear load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the harmonic wave holddown, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, the harmonic current of opposite direction suppresses the mains by harmonics electric current.

Optionally, in an embodiment of the present invention, described controller, further concrete for when existing nonlinear load has reactive load again after the zero load of PWM rectifier and the electrical network point of common coupling, place harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, harmonic current and the reactive current of opposite direction, electrical network is carried out harmonic current inhibition and reactive power compensation; Perhaps, when PWM rectifier DC side has reactive load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and reactive power compensation state, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, electric network reactive-load is compensated; Perhaps, when PWM rectifier DC side has nonlinear load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and harmonic wave holddown, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, the mains by harmonics electric current is suppressed.

Optionally, in an embodiment of the present invention, described controller, further concrete being used for when PWM rectifier DC side when existing nonlinear load has reactive load again afterwards with load and electrical network point of common coupling, place PWM rectification and harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, send harmonic current and the reactive current opposite with mains by harmonics size of current equal direction, suppress and reactive power compensation electrical network is carried out harmonic current.

Technique scheme has following beneficial effect: obtain the control law that the interconnected and damping based on Port-Controlled dissipation Hamilton model of PWM rectifier configures because adopt by Lagrange-Xia Bi integration method; The composite controller that forms with the Passive Shape Control controller as the PWM rectifier will be repeated to control, according to described control law, by repeating control Passive Shape Control is compensated, with the technological means that PERIODIC INTERFERENCE is suppressed, so reached following technique effect: suppress preferably the mains by harmonics interference in the situation that do not detect load harmonic current when can realize unity power factor PWM rectification, to improve the quality of power supply.

Description of drawings

In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art, the below will do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art, apparently, accompanying drawing in the following describes only is some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is a kind of pulse width modulation (PWM) Rectifier of embodiment of the invention flow chart;

Fig. 2 is that a kind of PWM rectifier of the embodiment of the invention forms structural representation;

Fig. 3 is application example PWM rectifier of the present invention and electric network wiring scheme;

Fig. 4 is application example PWM rectifier structure figure of the present invention;

Fig. 5 is application example PWM rectifier control principle drawing of the present invention;

Fig. 6 is that application example PWM rectifier of the present invention is based on the control block diagram of passivity control method under the d reference axis that repeats control and compensation;

Fig. 7 is that application example PWM rectifier of the present invention is based on the control block diagram of passivity control method under the q coordinate system that repeats control and compensation.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the invention, the technical scheme in the embodiment of the invention is clearly and completely described, obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills belong to the scope of protection of the invention not making the every other embodiment that obtains under the creative work prerequisite.

As shown in Figure 1, be a kind of pulse width modulation (PWM) Rectifier of embodiment of the invention flow chart, described PWM Rectifier is that the method comprises based on the passivity control method that repeats control and compensation:

101, obtain the control law based on the interconnected and damping of Port-Controlled dissipation Hamilton model configuration of PWM rectifier by Lagrange-Xia Bi integration method;

102, will repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, by repeating control Passive Shape Control be compensated, so that PERIODIC INTERFERENCE is suppressed.

Optionally, describedly will repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprise: will repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, under the effect of repeating signal generator, by the Cycle by Cycle compensation to the waveform error of the Passive Shape Control signal of described PWM rectifier, meritorious to realize first-harmonic when the stable state, or idle, or higher harmonic current disturbs, or the PERIODIC INTERFERENCE that " dead time effect " brings suppresses.

Optionally, described according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprise: when PWM rectifier DC side does not have other non-linear or reactive loads after the point of common coupling during with load and in the electrical network, the PWM rectifier is placed the PWM rectification state, utilize described passivity control method based on repeating control and compensation to make point of common coupling power network current before be unity power factor; Perhaps, when only having reactive load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the reactive power compensation state, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send reactive current electrical network is carried out reactive power compensation; Perhaps, when only having nonlinear load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the harmonic wave holddown, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, the harmonic current of opposite direction suppresses the mains by harmonics electric current.

Optionally, described according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprise: when existing nonlinear load has reactive load again after the point of common coupling in the zero load of PWM rectifier and the electrical network, place harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, harmonic current and the reactive current of opposite direction, electrical network is carried out harmonic current inhibition and reactive power compensation; Perhaps, when PWM rectifier DC side has reactive load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and reactive power compensation state, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, electric network reactive-load is compensated; Perhaps, when PWM rectifier DC side has nonlinear load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and harmonic wave holddown, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, the mains by harmonics electric current is suppressed.

Optionally, described according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprise: when PWM rectifier DC side when existing nonlinear load has reactive load again after the point of common coupling in load and electrical network, place PWM rectification and harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, send harmonic current and the reactive current opposite with mains by harmonics size of current equal direction, suppress and reactive power compensation electrical network is carried out harmonic current.

As shown in Figure 2, be a kind of PWM rectifier structure of embodiment of the invention schematic diagram, described PWM rectifier is controlled based on the passivity control method that repeats control and compensation, and described PWM rectifier 21 comprises:

Controller 211 is used for obtaining the control law that the interconnected and damping based on Port-Controlled dissipation Hamilton model of PWM rectifier configures by Lagrange-Xia Bi integration method; With repeating to control the composite controller that forms with the Passive Shape Control controller as the PWM rectifier, according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed.

Optionally, described controller 211, concrete be used for to repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, under the effect of repeating signal generator, by the Cycle by Cycle compensation to the waveform error of the Passive Shape Control signal of described PWM rectifier, to realize PERIODIC INTERFERENCE inhibition meritorious or idle to first-harmonic or that higher harmonic current disturbs or " dead time effect " brings when the stable state.

Optionally, described controller 211, further concrete being used for when PWM rectifier DC side during with load and electrical network point of common coupling when not having afterwards other non-linear or reactive loads, the PWM rectifier is placed the PWM rectification state, utilize described passivity control method based on repeating control and compensation to make point of common coupling power network current before be unity power factor; Perhaps, when only having reactive load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the reactive power compensation state, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send reactive current electrical network is carried out reactive power compensation; Perhaps, when only having nonlinear load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the harmonic wave holddown, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, the harmonic current of opposite direction suppresses the mains by harmonics electric current.

Optionally, described controller 211, further concrete for when existing nonlinear load has reactive load again after the zero load of PWM rectifier and the electrical network point of common coupling, place harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, harmonic current and the reactive current of opposite direction, electrical network is carried out harmonic current inhibition and reactive power compensation; Perhaps, when PWM rectifier DC side has reactive load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and reactive power compensation state, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, electric network reactive-load is compensated; Perhaps, when PWM rectifier DC side has nonlinear load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and harmonic wave holddown, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, the mains by harmonics electric current is suppressed.

Optionally, described controller 211, further concrete being used for when PWM rectifier DC side when existing nonlinear load has reactive load again afterwards with load and electrical network point of common coupling, place PWM rectification and harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, send harmonic current and the reactive current opposite with mains by harmonics size of current equal direction, suppress and reactive power compensation electrical network is carried out harmonic current.

Said method of the present invention or device technique scheme have following beneficial effect: technique scheme has following beneficial effect: obtain the control law that the interconnected and damping based on Port-Controlled dissipation Hamilton model of PWM rectifier configures because adopt by Lagrange-Xia Bi integration method; The composite controller that forms with the Passive Shape Control controller as the PWM rectifier will be repeated to control, according to described control law, by repeating control Passive Shape Control is compensated, with the technological means that PERIODIC INTERFERENCE is suppressed, so reached following technique effect: suppress preferably the mains by harmonics interference in the situation that do not detect load harmonic current when can realize unity power factor PWM rectification, to improve the quality of power supply.

PWM rectifier on traditional meaning of present routine only has unit power factor rectifier power, the electric current that guarantees the inflow rectifier is unity power factor, thereby avoid the PWM rectifier to cause harmonic pollution in electric power net, and the described PWM rectifier of the embodiment of the invention can guarantee that the electric current of electrical network is unity power factor before the PWM rectifier point of common coupling, thereby realizes the harmonic wave of electrical network is suppressed and reactive power compensation.Below lift application example and introduce in detail the described scheme of the embodiment of the invention:

According to the shortcoming of existing PWM rectifier and Active Power Filter-APF, application example of the present invention proposes a kind of PWM rectifier and control method.This kind PWM rectifier guarantees that by power network current is carried out the PWM rectification power network current is unity power factor.Therefore, this kind PWM rectifier can be realized self unit power factor rectifier, can realize that again harmonic wave and reactive current that other nonlinear loads in the electrical network are caused realize suppressing and compensation, have the function of PWM rectifier and Active Power Filter-APF simultaneously.

As shown in Figure 3, be application example PWM rectifier of the present invention and electric network wiring scheme; As shown in Figure 4, be application example PWM rectifier structure figure of the present invention.Details are as follows for this PWM rectifier control strategy:

The control strategy of PWM rectifier is one of guardian technique that guarantees its performance.Because the main circuit of PWM rectifier is typical nonlinear organization, conventional Linear Control may cause its job insecurity.Passivity control is a kind of nonlinear control method, because of its energy and injection nonlinear dampling by redistributing system, force system's gross energy to follow the tracks of the energy function of expectation, and the state variable asymptotic convergence that makes system is to set point, be the control method of a kind of global definition and Existence of Global Stable, have without singular point simplicity of design, robustness (is the transliteration of robust, is the technical term of control theory aspect.Be used for " robustness " of description control system, characterization control system is to the insensitivity of characteristic or Parameter Perturbation.In the situation that system parameters changes or have the external interference control system still can stable operation) strong characteristics, caused researcher's extensive concern.

Therefore, the control method of the described PWM rectifier of this patent has adopted Passive Shape Control (the Interconnection and Damping Assignment Passivity-Based Control IDA-PBC) method based on the interconnected and damping configuration of Port-Controlled dissipation Hamilton (PortControlled Hamiltonian with Dissipation PCHD) model, realizes the derivation of control law by interconnected matrix and the injection Damping work item of update the system.But in the process of utilizing IDA-PBC control method derivation system control law, find the solution nonlinear partial differential equation and have certain difficulty, present Research Literature often adopts hypothesis to choose or the method supposing to derive is found the solution the control law of PWM rectifier, some loss of learning that causes system makes system can not get desirable control effect.For above-mentioned existing problem, this patent adopts Lagrange-Xia Bi method of quadrature to find the solution partial differential equation, for the PWM rectifier design gone out a kind of perfect information the IDA-PBC controller.

Because the PWM rectifier is other nonlinear loads and reactive load electric current in the detection of grid not, and the control target-power network current of other nonlinear loads and reactive load electric current and PWM rectifier has relation in the electrical network, therefore, other nonlinear loads and reactive load electric current are interference volume in the controller of PWM rectifier in the electrical network.Because other nonlinear loads and reactive load electric current are for once arriving repeatedly idle and harmonic current, in order to suppress it to the interference of PWM rectifier control, control method to the PWM rectifier is improved, and has adopted based on the passivity control method that repeats control and compensation.As shown in Figure 5, be application example PWM rectifier control principle drawing of the present invention.

In the PWM of Fig. 4 rectifier structure figure, S _A1, S _A2, S _B1, S _B2, S _C1, S _C2Represent the switching tube of the every phase brachium pontis of PWM rectifier, L represents the outputting inductance of every phase, and R represents outputting inductance internal resistance and every mutually brachium pontis upper, lower tube interlocking dead band pressure drop equiva lent impedance sum.C represents the filter capacitor on the dc bus, R _LRepresent the load of PWM rectifier DC side, i _DcBe load current.Its Mathematical Modeling is suc as formula shown in (1):

$\left\{\begin{array}{c}L\frac{{\mathrm{di}}_{\mathrm{sa}}}{\mathrm{dt}}+{\mathrm{Ri}}_{\mathrm{ca}}=u_{\mathrm{sa}}-S_a{V}_{\mathrm{dc}}-u_{\mathrm{NO}}\\ L\frac{{\mathrm{di}}_{\mathrm{sb}}}{\mathrm{dt}}+{\mathrm{Ri}}_{\mathrm{cb}}=u_{\mathrm{sb}}-S_b{V}_{\mathrm{dc}}-u_{\mathrm{NO}}\\ L\frac{{\mathrm{di}}_{\mathrm{sc}}}{\mathrm{dt}}+{\mathrm{Ri}}_{\mathrm{cc}}=u_{\mathrm{sc}}-S_c{V}_{\mathrm{dc}}-u_{\mathrm{NO}}\\ C\frac{{\mathrm{DV}}_{\mathrm{dc}}}{\mathrm{dt}}=i_a{S}_a+i_b{S}_b+i_c{S}_c-i_{\mathrm{dc}}\\ u_{\mathrm{NO}}=-\frac{1}{3}{V}_{\mathrm{dc}}(S_a+S_b+S_c)\end{array}\right.---\left(1\right)$

S wherein _iBe switch function, its expression formula is:

Because the discontinuity of switch function.Therefore be difficult to carry out the passivity design.When switching frequency is very high, State-space Averaging Principle is a kind of effective method that addresses this problem.According to this concept, can replace switch function itself with the mean value of switch function in a switch periods, obtain the space State Average Model to Time Continuous.Such S _iMean value in the switch periods is because switch function is that amplitude is 1 pulse, so its mean value equals its duty ratio, S _i∈ [0,1].

Following formula is carried out the dq conversion, obtains PWM rectifier Mathematical Modeling under the dq coordinate system suc as formula (3):

$\left\{\begin{array}{c}L\frac{{\mathrm{di}}_{\mathrm{sd}}}{\mathrm{dt}}=u_{\mathrm{sd}}-{\mathrm{Ri}}_{\mathrm{sd}}+{\mathrm{\ωLi}}_{\mathrm{sq}}-S_d{V}_{\mathrm{dc}}\\ L\frac{{\mathrm{di}}_{\mathrm{sq}}}{\mathrm{dt}}=u_{\mathrm{sq}}-\mathrm{\ω}{\mathrm{Li}}_{\mathrm{sd}}-{\mathrm{Ri}}_{\mathrm{sq}}-S_q{V}_{\mathrm{dc}}\\ \frac{2}{3}C\frac{{\mathrm{dV}}_{\mathrm{dc}}}{\mathrm{dt}}=S_d{i}_{\mathrm{sd}}+S_q{i}_{\mathrm{sq}}-\frac{{2V}_{\mathrm{dc}}}{{3R}_L}\end{array}\right.---\left(3\right)$

Order

x ₂=Li _Sd, x ₃=Li _Sq, the total energy function of system is

Then the PCHD model of PWM rectifier is:

$\left\{\begin{array}{c}\stackrel{\·}{x}=(J\left(x\right)-R\left(x\right))\frac{\∂H\left(x\right)}{\∂x}+g_1\left(x\right)u+(-\frac{3}{2}{i}_{\mathrm{dc}})g_2\left(x\right)\\ y={g_1}^T\left(x\right)\frac{\∂H\left(x\right)}{\∂x}\end{array}\right.---\left(4\right)$

Wherein,

$g_1\left(x\right)=\left[\begin{array}{ccc}0& 0& 0\\ 1& 0& 0\\ 0& 1& 0\end{array}\right],u=\left[\begin{array}{c}{u}_{\mathrm{<figure-callout\; id="0"\; label="sd\; u\; sq"\; filenames="HDA00002118022400071.png"\; state="\{\{state\}\}">sd</figure-callout>}}& \\ u_{\mathrm{sq}}{}_{}\\ 0\end{array}\right],g_2\left(x\right)=\left[\begin{array}{c}1\\ 0\\ 0\end{array}\right]---\left(5\right)$

And satisfy J (x)=-J ^T(x), R (x)=(R (x)) ^T〉=0 is symmetrical positive semidefinite matrix.

According to the IDA-PB control principle, obtain:

$\left\{\begin{array}{c}(J_d\left(x\right)-R_d\left(x\right))\frac{{\&PartialD;H}_a\left(x\right)}{\&PartialD;x}=-(J_a\left(x\right)-R_a\left(x\right))\frac{\&PartialD;H\left(x\right)}{\&PartialD;x}+g_1\left(x\right)u+(-\frac{3}{2}{i}_{\mathrm{dc}})g_2\left(x\right)\\ J_d\left(x\right)=J\left(x\right)+J_a\left(x\right)\\ R_d\left(x\right)=R\left(x\right)+R_a\left(x\right)\\ H_d\left(x\right)=H\left(x\right)+H_a\left(x\right)\\ \frac{{\&PartialD;H}_a\left(x\right)}{\&PartialD;x}=K\left(x\right)\end{array}\right.---\left(6\right)$

Order $k\left(x\right)={\left(\begin{array}{ccc}{k}_1\left(x\right)& k_2\left(x\right)& k_3\left(x\right)\end{array}\right)}^T={\left(\begin{array}{ccc}\frac{{\&PartialD;H}_a\left(x\right)}{{\&PartialD;x}_1}& \frac{{\&PartialD;H}_a\left(x\right)}{{\&PartialD;x}_2}& \frac{{\&PartialD;H}_a\left(x\right)}{{\&PartialD;x}_3}\end{array}\right)}^T,$ J _a(x)=0, R _a(x)=[R _A1R _A2R _A3] ^T, then formula (6) can be put in order and is:

$(J\left(x\right)-R_d\left(x\right))k\left(x\right)-R_a\left(x\right)\frac{\&PartialD;H\left(x\right)}{\&PartialD;x}=g_1\left(x\right)u+(-\frac{3}{2}{i}_{\mathrm{dc}})g_2\left(x\right)---\left(7\right)$

With formula (5) substitution formula (7), put in order:

$\left\{\begin{array}{c}{S}_d=-\frac{2[(R+R_{a2})k_2\left(x\right)-\mathrm{\&omega;}{\mathrm{Lk}}_3\left(x\right)+\frac{R_{a2}}{L}{x}_2+u_{\mathrm{sd}}]}{{3k}_1\left(x\right)}\\ S_q=-\frac{2[{\mathrm{\&omega;Lk}}_2\left(x\right)+\left({R+R}_{a3}\right)k_3\left(x\right)+\frac{R_{a3}}{L}{x}_3+u_{\mathrm{sq}}]}{{3k}_1\left(x\right)}\\ R_{a1}{k}_1^2\left(x\right)-(\frac{3}{2}{i}_{\mathrm{dc}}-\frac{{2R}_{a1}}{3C}{x}_1)k_1\left(x\right)+(R+R_{a2})k_2^2\left(x\right)+\frac{R_{a2}}{L}{x}_2{k}_2\left(x\right)+\\ u_{\mathrm{sd}}{k}_2\left(x\right)+(R+R_{a3})k_3^2\left(x\right)+(\frac{R_{a3}}{L}{x}_3+u_{\mathrm{sq}})k_3\left(x\right)=0\end{array}\right.---\left(8\right)$

According to The 3rd equation by formula (8) obtains the first order nonlinear partial differential equation:

$R_{a1}{\left(\frac{{\&PartialD;H}_a\left(x\right)}{{\&PartialD;x}_1}\right)}^2-(\frac{3}{2}{i}_{\mathrm{dc}}-\frac{2R_{a1}}{3C}{x}_1)\frac{\&PartialD;H_a\left(x\right)}{{\&PartialD;x}_1}+(R+R_{a2}){\left(\frac{\&PartialD;H_a\left(x\right)}{{\&PartialD;x}_2}\right)}^2$ （9）

$(\frac{R_{a2}{x}_2}{L}+u_{\mathrm{sd}})\frac{{\&PartialD;H}_a\left(x\right)}{{\&PartialD;x}_2}+(R+R_{a3}){\left(\frac{{\&PartialD;H}_a\left(x\right)}{\&PartialD;x_3}\right)}^2+(\frac{R_{a3}{x}_3}{L}+u_{\mathrm{sq}})\frac{\&PartialD;H_a\left(x\right)}{{\&PartialD;x}_3}=0$

According to Lagrange-Xia Bi method of quadrature, first order nonlinear partial differential equation (9) belongs to F (x ₁, x ₂, x ₃, k ₁, k ₂, k ₃The type of)=0 does not contain H in equation _a(x), then $\frac{\&PartialD;F}{\&PartialD;H_a\left(x\right)}=0,$ And $\frac{\&PartialD;F}{\&PartialD;x_1}=\frac{{2R}_{a1}}{3C}{k}_1\left(x\right),$ $\frac{\&PartialD;F}{\&PartialD;x_2}=\frac{R_{a2}}{L}{k}_2\left(x\right),$ $\frac{\&PartialD;F}{{\&PartialD;x}_3}=\frac{R_{a3}}{L}{k}_3\left(x\right),$ Wherein, $k_1\left(x\right)=\frac{{\&PartialD;H}_a\left(x\right)}{{\&PartialD;x}_1},$ $k_2\left(x\right)=\frac{{\&PartialD;H}_a\left(x\right)}{{\&PartialD;x}_2},$ $k_3\left(x\right)=\frac{{\&PartialD;H}_a\left(x\right)}{{\&PartialD;x}_3},$ And:

$\left\{\begin{array}{c}\frac{\&PartialD;F}{{\&PartialD;k}_1\left(x\right)}={2R}_{a1}{k}_1\left(x\right)+\frac{{2R}_{a1}}{3C}{x}_1-\frac{3}{2}{i}_{\mathrm{dc}}\\ \frac{\&PartialD;F}{{\&PartialD;k}_2\left(x\right)}=2(R+R_{a2})k_2\left(x\right)+\frac{R_{a2}}{L}{x}_2+u_{\mathrm{sd}}\\ \frac{\&PartialD;F}{{\&PartialD;k}_3\left(x\right)}=2(R+R_{a3})k_3\left(x\right)+\frac{R_{a3}}{L}{x}_3+u_{\mathrm{sq}}\end{array}\right.---\left(10\right)$

According to formula (9), formula (10), obtain equation group:

$\frac{{\mathrm{dk}}_1\left(x\right)}{\frac{{2R}_{a1}}{3C}{k}_1\left(x\right)}=\frac{{\mathrm{dk}}_2\left(x\right)}{\frac{R_{a2}}{L}{k}_2\left(x\right)}=\frac{{\mathrm{dk}}_3\left(x\right)}{\frac{R_{a3}}{L}{k}_3\left(x\right)}=\frac{{\mathrm{dx}}_1}{-(2R_{a1}{k}_1\left(x\right)+\frac{{2R}_{a1}}{3C}{x}_1-\frac{3}{2}{i}_{\mathrm{dc}})}=$ （11）

$\frac{{\mathrm{dx}}_2}{-(2(R+R_{a2})k_2\left(x\right)+\frac{R_{a2}}{L}{x}_2+u_{\mathrm{sd}})}=\frac{{\mathrm{dx}}_3}{-(2(R+R_{a3})k_3\left(x\right)+\frac{R_{a3}}{L}{x}_3+u_{\mathrm{sq}})}$

According to the first integral principle, in formula (11):

$\frac{{\mathrm{dk}}_1\left(x\right)}{\frac{{2R}_{a1}}{3C}{k}_1\left(x\right)}=\frac{{\mathrm{dx}}_1}{-(2R_{a1}{k}_1\left(x\right)+\frac{{2R}_{a1}}{3C}{x}_1-\frac{3}{2}{i}_{\mathrm{dc}})}---\left(12\right)$

Both sides are integration simultaneously:

${3\mathrm{CR}}_{a1}{k}_1{\left(x\right)}^2-\frac{9}{2}{\mathrm{Ci}}_{\mathrm{dc}}{k}_1\left(x\right)=-{2R}_{a1}{x}_1{k}_1\left(x\right)+c_1---\left(13\right)$

Wherein, c ₁Be constant.In like manner, got by formula (11):

$\left\{\begin{array}{c}L(R+R_{a2})k_2{\left(x\right)}^2+{\mathrm{Lu}}_{\mathrm{sd}}{k}_2\left(x\right)=-R_{a2}{x}_2{k}_2\left(x\right)+c_2\\ L(R+R_{a3})k_3{\left(x\right)}^2+{\mathrm{Lu}}_{\mathrm{sq}}{k}_3\left(x\right)=-R_{a3}{x}_3{k}_3\left(x\right)+c_3\end{array}\right.---\left(14\right)$

C wherein ₂, c ₃Be constant.That is:

$\left\{\begin{array}{c}{3\mathrm{CR}}_{a1}{k}_1{\left(x\right)}^2-\frac{9}{2}{\mathrm{Ci}}_{\mathrm{dc}}{k}_1\left(x\right)+{2R}_{a1}{x}_1{k}_1{\left(x\right)}^2=c_1\\ L(R+R_{a2})k_2{\left(x\right)}^2+(R_{a2}{x}_2+{\mathrm{Lu}}_{\mathrm{sd}})k_2\left(x\right)=c_2\\ L(R+R_{a3})k_3{\left(x\right)}^2+(R_{a3}{x}_3+{\mathrm{Lu}}_{\mathrm{sq}})k_3\left(x\right)=c_3\end{array}\right.---\left(15\right)$

The control target of PWM rectifier is surveyed direct current voltage V exactly _DcBe stabilized to set point V _Dc ^*, realize current on line side sineization and unity power factor, therefore, the expectation balance point of this system is

I wherein _mThe amplitude of AC phase current during for steady operation,

Configuration condition according to expectation balance point: at expectation balance point

The place, K (x) satisfies $K\left(x^{*}\right)=-\frac{\&PartialD;H\left(x^{*}\right)}{\&PartialD;x},$ :

$\left\{\begin{array}{c}{k}_1\left(x^{*}\right)=-\frac{{2x}_1^{*}}{3c}=-V_{\mathrm{dc}}^{*}\\ k_2\left(x^{*}\right)=-\frac{x_2^{*}}{L}=-I_m\\ k_3\left(x^{*}\right)=-\frac{x_3^{*}}{L}=0\end{array}\right.---\left(16\right)$

With formula (16) substitution formula (15),

c ₂=(RI _m-u _Sd) LI _m, c ₃=0.Then:

$\left\{\begin{array}{c}{k}_1\left(x\right)=-\frac{{2R}_{a1}{x}_1-{9\mathrm{Ci}}_L}{12{\mathrm{CR}}_{a1}}-\sqrt{\frac{{3i}_{\mathrm{dc}}{V}_{\mathrm{dc}}^{*}}{{2R}_{a1}}+{\left(\frac{2R_{a1}{x}_1-{9\mathrm{Ci}}_L}{{12\mathrm{CR}}_{a1}}\right)}^2}\\ k_2\left(x\right)=-\frac{{\mathrm{Lu}}_{\mathrm{sd}}+R_{a2}{x}_2}{2L(R+R_{a2})}+\sqrt{{\left(\frac{{\mathrm{Lu}}_{\mathrm{sd}}+R_{a2}{x}_2}{2L(R+R_{a2})}\right)}^2+\frac{({\mathrm{RI}}_m-u_{\mathrm{sd}})I_m}{R+R_{a2}}}\\ k_3\left(x\right)=0\end{array}\right.---\left(17\right)$

In order to keep PWM rectifier DC side voltage stabilization at set point V _Dc ^*Must absorb active current from system.The general outer voltage that adds is controlled.Because the PWM rectifier itself is typically to owe drive system.So system's control target at this moment can be modified to:

$x_1^{*}=I_m={\mathrm{\&Delta;i}}_{\mathrm{sd}}---\left(18\right)$

Δ i _SdIn order to guarantee that dc voltage maintains the active power that set point absorbs.For tracking performance and the robustness that improves system, introduce classical PI control (proportional plus integral control is control theory aspect term, Proportional integral) herein.

Δi _sd＝K _p(V _dc ^*-V _dc)+K _i∫(V _dc ^*-V _dc)dt(19)

K _pAnd K _iBe respectively corresponding ratio and integral coefficient.

Periodically (dead time effect is caused by the dead band with containing high-frequency harmonic component and PWM rectifier main circuit electronic power switch " dead time effect " owing to other nonlinear load electric currents in the electrical network are, so-called dead band, at electric and electronic technical field, for the simultaneously conductings of two electric and electronic power switches that prevent same brachium pontis, form short circuit and burn device.In order to guarantee the safety of device, therefore after the previous power switch of same brachium pontis turn-offed, a next power switch inserted a Dead Time before opening, and at this moment, two power of same brachium pontis are opened and all are in cut-off state.Owing in the middle of each switch periods, all needing to add Dead Time, can cause the time of power switch to change, and then cause the voltage of device or electric current to change, be not inconsistent with desired value.This consequence of being brought by the dead band is called dead time effect.) bring the characteristics of PERIODIC INTERFERENCE, so the characteristics that the interference of PWM rectifier controller is periodically and high frequency content is enriched.For the PWM rectifier is carried out fine control, power network current is carried out the broad sense unit power factor rectifier, must carry out fine inhibition to this interference.Repeating control is based on internal model principle and (the kinetic model implant controller of external action signal is consisted of a kind of design principle of high accuracy feedback control system.This principle points out, any one can offset the feedback control system of external disturbance or track reference input signal well, and its feedback loop must comprise a kinetic model identical with external input signal.This internal model is called internal mold) a kind of control method.Its basic thought is under the prerequisite that the distortion that supposing the system occurred in the last primitive period will repeat in the same time of next primitive period, controller is reference-input signal and the deviation of the feedback signal time-delay one-period of this cycle system, then the synchronization in next cycle is superimposed upon this signal on the original control signal, disturbs with the repeatability that will occur in each cycle after eliminating.Because it is meritorious, the idle and higher harmonic current of first-harmonic that the PWM rectifier disturbs input signal, repetitive controller utilization " repeating signal generator " internal mold has solved this problem dexterously.Under the effect of repeating signal generator, in fact controller is carrying out a kind of integral control of Cycle by Cycle, by the Cycle by Cycle compensation to waveform error, can realize during stable state that PERIODIC INTERFERENCE meritorious, idle to first-harmonic and that higher harmonic current disturbs and " dead time effect " brings suppresses fully.Repeat to control unique known features---the repeatability that takes full advantage of about disturbance, alleviated thus the difficulty of control.Have algorithm simple, less demanding to control rate, and the advantage that can realize leading control, have extraordinary steady-state behaviour.But within a reference cycle of disturbing after occurring, repetitive controller does not produce any regulating action to disturbing, system almost is in the open loop state of a control in this cycle, eliminate to disturb a reference cycle is wanted in the impact of controller at least, therefore, bad dynamic performance preferably combines use with other control methods.Therefore, consider the pluses and minuses of passivity control and the pluses and minuses that repeat to control, have complementary advantages in order to make two kinds of control methods, propose based on the PWM rectifier control mode that repeats control and compensation.As shown in Figure 6, be passivity control method the control block diagram under d reference axis of application example PWM rectifier of the present invention based on the repetition control and compensation; As shown in Figure 7, be passivity control method the control block diagram under q coordinate system of application example PWM rectifier of the present invention based on the repetition control and compensation.In repeating to control, in order to reduce it in the gain of high band, generally in control, add low pass filter Q (s), e ^-TsBe pure time delay process, the error in this cycle is delayed time next cycle.Therefore, the PWM rectifier passivity control law of repetition control and compensation is:

$\left\{\begin{array}{c}{S}_d=-\frac{2[(R+R_{a2})k_2\left(x\right)-\mathrm{\&omega;}{\mathrm{Lk}}_3\left(x\right)+\frac{R_{a2}}{L}{x}_2+u_{\mathrm{sd}}}{{3k}_1\left(x\right)}-\frac{e^{-T\frac{(\mathrm{\&Delta;}{i}_{\mathrm{sd}}-i_{\mathrm{sd}})}{\mathrm{dt}}}}{(1+T_L\frac{d(\mathrm{\&Delta;}{i}_{\mathrm{sd}}-i_{\mathrm{sd}})}{\mathrm{dt}}-e^{-T\left(\frac{{\mathrm{\&Delta;i}}_{\mathrm{sd}}-i_{\mathrm{sd}}}{\mathrm{dt}}\right)})V_{\mathrm{dc}}}\\ S_q=-\frac{2[\mathrm{\&omega;}{\mathrm{Lk}}_2\left(x\right)+(R+R_{a3})k_3\left(x\right)+\frac{R_{a3}}{L}{x}_3+u_{\mathrm{sq}}}{{3k}_1\left(x\right)}-\frac{e^{T\frac{{\mathrm{di}}_{\mathrm{sq}}}{\mathrm{dt}}}}{(1-T_L\frac{{\mathrm{di}}_{\mathrm{sq}}}{\mathrm{dt}}-e^{T\frac{{\mathrm{di}}_{\mathrm{sq}}}{\mathrm{dt}}})V_{\mathrm{dc}}}\end{array}\right.---\left(20\right)$

T wherein _LBe the time parameter of low pass filter Q (s), T is the primitive period of system power supply, k ₁(x), k ₂(x), k ₃(x) as the formula (17), Δ i _SdAs the formula (19).

Application example of the present invention has or not nonlinear load and reactive load can be divided into seven kinds of operating states according to the electrical network of PWM rectifier institute loading position:

(1) PWM rectification state

As PWM DC side point of common coupling (Point of common coupling, PCC during with load and in the electrical network.Electric upper and point that particular user device is nearest can connect or connect other user's sets in this in the public supply network of point of common coupling.When the tie point that refers in the present invention PWM rectifier unit and electrical network) not having afterwards other non-linear or reactive loads, the PWM rectifier is placed the PWM rectification state, is unity power factor based on power network current before the passivity control method assurance point of common coupling that repeats control and compensation.

Unity power factor, namely power factor is that the voltage and current that electrical network provides is the synchronous first-harmonic of same frequency for 1..

According to physical knowledge as can be known, power is the product of voltage and electric current, i.e. P=ui.Power is divided into looking and carries a power S in electric power system, and active-power P and reactive power Q be S wherein ²=P ²+ Q ²Because voltage and current is sine wave in the electrical network.As voltage u=U _mCos ω t, electric current are i=i _mCos (ω t+ ψ)

The active power that provides of electrical network then $P=\mathrm{ui}=\frac{1}{2\mathrm{\&pi;}}{\&Integral;}_0^{2\mathrm{\&pi;}}{U}_m\cos \mathrm{\&omega;t}\&CenterDot;i_m\cos (\mathrm{\&omega;t}+\mathrm{\&psi;})\mathrm{dt}=U_m{i}_m\cos \mathrm{\&psi;}$

Reactive power Q=U _mi _mSin ψ is depending on carrying power S=U _mi _m

Power factor is active power and the ratio of looking year power.Namely

When system voltage electric current same-phase, ψ=0, then power factor (PF) Be also referred to as unity power factor.

The control method of being carried by the present invention, control realize that the electric network reactive-load electric current is 0, thereby realize the power network current unity power factor, and power network current is as unity power factor before to guarantee point of common coupling.

(2) reactive power compensation state

When only having reactive load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the reactive power compensation state, send reactive current based on the passivity control method control PWM rectifier that repeats control and compensation electrical network is carried out reactive power compensation.

(3) harmonic wave holddown

When only having nonlinear load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the harmonic wave holddown, based on the passivity control method control PWM rectifier that repeats control and compensation send with the mains by harmonics size of current equate, the harmonic current of opposite direction, the mains by harmonics electric current is suppressed.

(4) reactive power compensation and harmonic wave holddown

When existing nonlinear load has reactive load again after the point of common coupling in the zero load of PWM rectifier and the electrical network, place harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, based on the passivity control method control PWM rectifier that repeats control and compensation send with the mains by harmonics size of current equate, harmonic current and the reactive current of opposite direction, electrical network is carried out harmonic current inhibition and reactive power compensation.

(5) PWM rectification and reactive power compensation state

When PWM rectifier DC side has reactive load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and reactive power compensation state, when based on the passivity control method control PWM rectifier that repeats control and compensation self institute's bringing onto load being realized the PWM rectification, electric network reactive-load is compensated.

(6) PWM rectification and harmonic wave holddown

When PWM rectifier DC side has nonlinear load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and harmonic wave holddown, when based on the passivity control method control PWM rectifier that repeats control and compensation self institute's bringing onto load being realized the PWM rectification, the mains by harmonics electric current is suppressed.

(7) PWM rectification and reactive power compensation and harmonic wave holddown

When PWM rectifier DC side when existing nonlinear load has reactive load again after the point of common coupling in load and electrical network, place PWM rectification and harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, when based on the passivity control method control PWM rectifier that repeats control and compensation self institute's bringing onto load being realized the PWM rectification, send with the mains by harmonics size of current equate, harmonic current and the reactive current of opposite direction, electrical network is carried out harmonic current suppresses and reactive power compensation.

Compared with the prior art, the passivity control method of application example PWM rectifier of the present invention and repetition control and compensation thereof has the following advantages:

(1) has under the condition that does not increase hardware cost with respect to conventional P WM rectifier that harmonic wave suppresses and the function of reactive power compensation.

(2) with respect to Active Power Filter-APF owing to not needing to detect load harmonic wave and reactive current: 1) without harmonic wave and idle extraction algorithm, control algolithm is simple; 2) without the detection error of bringing in harmonic wave and the reactive current leaching process; 3) without the time-delay that brings in harmonic wave and the reactive current leaching process; 4) save three high accuracy and High-speed Electric flow sensor and three tunnel high accuracy and high speed signal modulate circuit; 5) the control system tracking target is DC quantity, and control is simple;

(3) has the bringing onto load function with respect to Active Power Filter-APF.

Those skilled in the art can also recognize the various illustrative components, blocks (illustrative logical block) that the embodiment of the invention is listed, the unit, and step can pass through electronic hardware, computer software, or both combinations realize.Be the clear replaceability (interchangeability) of showing hardware and software, above-mentioned various illustrative components (illustrative components), unit and step have been described their function generally.Such function is to realize depending on the designing requirement of specific application and whole system by hardware or software.Those skilled in the art can be for every kind of specific application, and can make ins all sorts of ways realizes described function, but this realization should not be understood to exceed the scope of embodiment of the invention protection.

Various illustrative logical block described in the embodiment of the invention, or the unit can pass through general processor, digital signal processor, application-specific integrated circuit (ASIC) (ASIC), field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the design of above-mentioned any combination realizes or operates described function.General processor can be microprocessor, and alternatively, this general processor also can be any traditional processor, controller, microcontroller or state machine.Processor also can realize by the combination of calculation element, for example digital signal processor and microprocessor, multi-microprocessor, Digital Signal Processor Core of one or more microprocessors associatings, or any other similarly configuration realize.

Method described in the embodiment of the invention or the step of algorithm can directly embed hardware, the software module of processor execution or the two combination.Software module can be stored in the storage medium of other arbitrary form in RAM memory, flash memory, ROM memory, eprom memory, eeprom memory, register, hard disk, moveable magnetic disc, CD-ROM or this area.Exemplarily, storage medium can be connected with processor so that processor can be from storage medium reading information, and can deposit write information to storage medium.Alternatively, storage medium can also be integrated in the processor.Processor and storage medium can be arranged among the ASIC, and ASIC can be arranged in the user terminal.Alternatively, processor and storage medium also can be arranged in the different parts in the user terminal.

In one or more exemplary designs, the described above-mentioned functions of the embodiment of the invention can realize in hardware, software, firmware or this three's combination in any.If realize in software, these functions can be stored on the medium with computer-readable, or are transmitted on the medium of computer-readable with one or more instructions or code form.The computer-readable medium comprises the computer storage medium and is convenient to so that allow computer program transfer to other local communication medium from a place.Storage medium can be the useable medium that any general or special computer can access.For example, such computer readable media can include but not limited to RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage device, or other anyly can be used for carrying or storage can be read by general or special computer or general or special processor the program code of form with instruction or data structure and other medium.In addition, any connection can suitably be defined as the computer-readable medium, for example, if software is by a coaxial cable, optical fiber computer, twisted-pair feeder, Digital Subscriber Line (DSL) or also being comprised in the defined computer-readable medium with wireless way for transmittings such as infrared, wireless and microwave from a web-site, server or other remote resource.Described video disc (disk) and disk (disc) comprise Zip disk, radium-shine dish, CD, DVD, floppy disk and Blu-ray Disc, and disk is usually with the magnetic duplication data, and video disc carries out the optical reproduction data with laser usually.Above-mentioned combination also can be included in the computer-readable medium.

Above-described embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is the specific embodiment of the present invention; the protection range that is not intended to limit the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

The present invention is by Chinese Petroleum Univ.'s prediction guiding fund project (2010QZ03) patronage.

Claims (10)

1. a pulse width modulation (PWM) Rectifier is characterized in that, described PWM Rectifier is that the method comprises based on the passivity control method that repeats control and compensation:

Obtain the control law based on the interconnected and damping of Port-Controlled dissipation Hamilton model configuration of PWM rectifier by Lagrange-Xia Bi integration method;

With repeating to control the composite controller that forms with the Passive Shape Control controller as the PWM rectifier, according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed.

2. pulse width modulation (PWM) Rectifier as claimed in claim 1, it is characterized in that, describedly will repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed, comprising:

The composite controller that forms with the Passive Shape Control controller as the PWM rectifier will be repeated to control, according to described control law, under the effect of repeating signal generator, by the Cycle by Cycle compensation to the waveform error of the Passive Shape Control signal of described PWM rectifier, to realize PERIODIC INTERFERENCE inhibition meritorious or idle to first-harmonic or that higher harmonic current disturbs or " dead time effect " brings when the stable state.

3. pulse width modulation (PWM) Rectifier as claimed in claim 1 is characterized in that, and is described according to described control law, by repeating control Passive Shape Control compensated, and so that PERIODIC INTERFERENCE is suppressed, comprising:

When PWM rectifier DC side does not have other non-linear or reactive loads after the point of common coupling during with load and in the electrical network, the PWM rectifier is placed the PWM rectification state, utilize described passivity control method based on repeating control and compensation to make point of common coupling power network current before be unity power factor; Perhaps,

When only having reactive load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the reactive power compensation state, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send reactive current electrical network is carried out reactive power compensation; Perhaps,

When only having nonlinear load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the harmonic wave holddown, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, the harmonic current of opposite direction suppresses the mains by harmonics electric current.

4. pulse width modulation (PWM) Rectifier as claimed in claim 1 is characterized in that, and is described according to described control law, by repeating control Passive Shape Control compensated, and so that PERIODIC INTERFERENCE is suppressed, comprising:

When existing nonlinear load has reactive load again after the point of common coupling in the zero load of PWM rectifier and the electrical network, place harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, harmonic current and the reactive current of opposite direction, electrical network is carried out harmonic current inhibition and reactive power compensation; Perhaps,

When PWM rectifier DC side has reactive load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and reactive power compensation state, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, electric network reactive-load is compensated; Perhaps,

When PWM rectifier DC side has nonlinear load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and harmonic wave holddown, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, the mains by harmonics electric current is suppressed.

5. pulse width modulation (PWM) Rectifier as claimed in claim 1 is characterized in that, and is described according to described control law, by repeating control Passive Shape Control compensated, and so that PERIODIC INTERFERENCE is suppressed, comprising:

When PWM rectifier DC side when existing nonlinear load has reactive load again after the point of common coupling in load and electrical network, place PWM rectification and harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, send harmonic current and the reactive current opposite with mains by harmonics size of current equal direction, suppress and reactive power compensation electrical network is carried out harmonic current.

6. a PWM rectifier is characterized in that, described PWM rectifier is controlled based on the passivity control method that repeats control and compensation, and described PWM rectifier comprises:

Controller is used for obtaining the control law that the interconnected and damping based on Port-Controlled dissipation Hamilton model of PWM rectifier configures by Lagrange-Xia Bi integration method; With repeating to control the composite controller that forms with the Passive Shape Control controller as the PWM rectifier, according to described control law, by repeating control Passive Shape Control is compensated, so that PERIODIC INTERFERENCE is suppressed.

7. PWM rectifier as claimed in claim 6 is characterized in that,

Described controller, concrete be used for to repeat to control the composite controller that forms with Passive Shape Control as the controller of PWM rectifier, according to described control law, under the effect of repeating signal generator, by the Cycle by Cycle compensation to the waveform error of the Passive Shape Control signal of described PWM rectifier, to realize PERIODIC INTERFERENCE inhibition meritorious or idle to first-harmonic or that higher harmonic current disturbs or " dead time effect " brings when the stable state.

8. PWM rectifier as claimed in claim 6 is characterized in that,

Described controller, further concrete being used for when PWM rectifier DC side during with load and electrical network point of common coupling when not having afterwards other non-linear or reactive loads, the PWM rectifier is placed the PWM rectification state, utilize described passivity control method based on repeating control and compensation to make point of common coupling power network current before be unity power factor; Perhaps, when only having reactive load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the reactive power compensation state, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send reactive current electrical network is carried out reactive power compensation; Perhaps, when only having nonlinear load after the point of common coupling in the zero load of PWM rectifier and the electrical network, the PWM rectifier is placed the harmonic wave holddown, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, the harmonic current of opposite direction suppresses the mains by harmonics electric current.

9. PWM rectifier as claimed in claim 6 is characterized in that,

Described controller, further concrete for when existing nonlinear load has reactive load again after the zero load of PWM rectifier and the electrical network point of common coupling, place harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, utilize described passivity control method control PWM rectifier based on repeating control and compensation to send with the mains by harmonics size of current to equate, harmonic current and the reactive current of opposite direction, electrical network is carried out harmonic current inhibition and reactive power compensation; Perhaps, when PWM rectifier DC side has reactive load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and reactive power compensation state, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, electric network reactive-load is compensated; Perhaps, when PWM rectifier DC side has nonlinear load after the point of common coupling in load and electrical network, the PWM rectifier is placed PWM rectification and harmonic wave holddown, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, the mains by harmonics electric current is suppressed.

10. PWM rectifier as claimed in claim 6 is characterized in that,

Described controller, further concrete being used for when PWM rectifier DC side when existing nonlinear load has reactive load again afterwards with load and electrical network point of common coupling, place PWM rectification and harmonic wave to suppress and the reactive power compensation state in the PWM rectifier, when utilizing described passivity control method control PWM rectifier based on repeating control and compensation that self institute's bringing onto load is realized the PWM rectification, send harmonic current and the reactive current opposite with mains by harmonics size of current equal direction, suppress and reactive power compensation electrical network is carried out harmonic current.

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