CN106330034A - Model predictive control method for simplified sampling of indirect matrix converter - Google Patents

Abstract

The present invention discloses a model predictive control method for simplified sampling of an indirect matrix converter (IMC). The method belongs to the control field of power electronics and electric drive. The method is based on module predictive control of an indirect matrix converter-inductor motor (IMC-IM) speed regulating system, and utilizes the indirect matrix converter to input a filter module to design and establish a novel observer, enables voltage observation at three phases of the input side of the indirect matrix converter, and utilizing the observation value to replace the detection value for predictive control. At the same time, a second-order difference quotient method is used to decouple the input reactive power prediction and the input voltage, in order to reduce dependency of the predictive control on the observation model. The method enables effective observation of three-phase input voltage to user the observation value to replace the detection value, reduces sampling demands in module predictive control, effectively simplifies controller AD sampling, digital filter and processing time delay, reduces system cost and greatly facilitates the realization of the system.

Description

Indirect matrix converter simplifies the model predictive control method of sampling

Technical field

The present invention relates to the control method of a kind of converters, particularly relate to a kind of indirect matrix converter and simplify The model predictive control method method of sampling.

Background technology

Indirect matrix converter is a kind of novel electric power electric changer, relative to traditional AC-DC-AC changer, tool Have that topology is simple, compact conformation, power density big and the advantage such as energy in bidirectional flow, be usually used in driving asynchronous machine to constitute exchange Governing system.Particularly space flight, military project etc. needs band carrying to turn but in the limited industrial application of spatial content.At indirect square In the Model Predictive Control strategy that battle array changer-asynchronous motor speed-regulating system is traditional, owing to need to meet motor load and electricity simultaneously The requirement of net, then need to be controlled magnetic linkage, electromagnetic torque and input reactive power.But its to there is detection limit numerous, sampling Conditioning cost is high, time extend, control algolithm complexity is difficult to the shortcoming that realizes, limits model predictive control method at indirect matrix Application on changer-asynchronous motor speed-regulating system.

Fig. 1 is indirect matrix converter-asynchronous motor speed-regulating system topological structure, by three-phase alternating-current supply (1), input LC Wave filter (2), the virtual rectification circuit of three-phase bridge (3), clamp circuit (4), the virtual inverter circuit of three-phase bridge (5), asynchronous electricity Machine (6) and two dc bus compositions.The most virtual rectification circuit is by six two-way switch Sr1, Sr2, Sr3, Sr4, Sr5, Sr6 Composition, can realize the two-way flow of energy.

It is that under different input voltage region, virtual rectification stage owns that virtual rectifier input voltage region divides such as Fig. 2, Fig. 3 Effective on off state, and according on off state such as Fig. 4 corresponding to the voltage vector of virtual inverter, indirect matrix converter C can be had altogether within a sampling period₃ ¹C₈ ¹=24 kinds of effective on off states.In order to realize system stable operation, adopt as shown in Figure 5 By the method for Model Predictive Control, motor load and electrical network index request are controlled.Its control structure includes electric machine rotor Flux observation, forecast model, merit functions optimize three parts.Wherein forecast model include stator magnetic linkage ψ, electromagnetic torque Te and Input reactive power Q.State equation based on asynchronous machine is observed (A) and obtains actual value and to its Europe rotor magnetic linkage It is pulled away from dispersion, is next based on forecast model (B) and stator magnetic linkage and electromagnetic torque under effective on off state are predicted, then root According to the performance requirement of system to merit functions optimization (C), finally select corresponding the opening of indirect matrix converter optimal voltage vector Off status.

Concrete control algolithm is carried out by following three steps:

A. electric machine rotor flux observation

According to the stator voltage equation of asynchronous machine, utilize Euler's formula to carry out discretization and rotor magnetic linkage is seen Surveying, formula is as follows:

${\stackrel{\→}{\mathrm{\ψ}}}_s^E\left(k\right)={\stackrel{\→}{\mathrm{\ψ}}}_s(k-1)+{\stackrel{\→}{v}}_o\left(k\right)T_s-T_s{R}_s{\stackrel{\→}{i}}_o\left(k\right)---\left(1\right)$

${{\stackrel{\→}{\mathrm{\ψ}}}_r}^E\left(k\right)=\frac{L_r}{L_m}{{\stackrel{\→}{\mathrm{\ψ}}}_s}^E\left(k\right)+(L_m-\frac{L_s{L}_r}{L_m}){\stackrel{\→}{i}}_o\left(k\right)---\left(2\right)$

R_s, R_r, L_s, L_r, L_mMotor stator resistance, rotor resistance, stator inductance, inductor rotor, rotor mutual inductance.

When electric machine rotor flux observation, output voltage v_oK () is to be switched by input voltage measurement value and current time State restructuring draws, it may be assumed that

B. forecast model

First stator magnetic linkage prediction is carried out.Rotor Flux estimation is after observation completes, it may be determined that stator magnetic linkage is predicted Formula is as follows:

${\stackrel{\→}{\mathrm{\ψ}}}_s^p(k+1)={\stackrel{\→}{\mathrm{\ψ}}}_s^E\left(k\right)+{\stackrel{\→}{v}}_o\left(k\right)T_s-T_s{R}_s{\stackrel{\→}{i}}_o\left(k\right)---\left(4\right)$

Then electromagnetic torque prediction is carried out.Relation according to motor electromagnetic torque with stator current obtains: realize electromagnetism The prediction of torque, it is necessary first to stator current i_oPrediction.Determine that stator current is pre-by asynchronous machine stator dynamical equation Survey formula is as follows:

$i_o(k+1)=(1+\frac{T_s}{{\mathrm{\τ}}_{\mathrm{\σ}}})\·{\stackrel{\→}{i}}_o\left(k\right)+\frac{T_s}{{\mathrm{\τ}}_{\mathrm{\σ}}+T_s}\·\{\frac{1}{R_{\mathrm{\σ}}}\·(\frac{k_r}{{\mathrm{\τ}}_r}-{\mathrm{jk}}_r\mathrm{\ω}){\stackrel{\→}{\mathrm{\ψ}}}_r\left(k\right)+{\stackrel{\→}{v}}_o\left(k\right)\}---\left(5\right)$

In above formula:

τ_σ=L_σ/R_σ, L_σ=σ L_s, τ_r=L_r/R_r, k_r=L_m/L_r.

Therefore according to stator magnetic linkage and the prediction of electric current, it may be determined that the predictor formula of the electromagnetic torque of motor is:

$T_e^p(k+1)=\frac{3}{2}p\left({\stackrel{\→}{\mathrm{\ψ}}}_s^p\right(k+1)\×{\stackrel{\→}{i}}_o^p(k+1\left)\right)---\left(6\right)$

In the forecast model of said stator magnetic linkage and electromagnetic torque, output voltage predictive value v_oK () is to be seen by input voltage Survey observation and the restructuring of all on off states of device, it may be assumed that

${\stackrel{\→}{v}}_o\left(k\right)={\stackrel{\→}{v}}_o^P\left(k\right)={\stackrel{\→}{v}}_i^E\left(k\right)*S(k+1)---\left(7\right)$

Finally carry out inputting reactive power prediction.According to indirect matrix converter input filter model, we are true with this Determine wave filter input current i_sPredictor formula be:

${{\stackrel{\→}{i}}_x}^p(k+1)={\mathrm{\Φ}}_3{\stackrel{\→}{v}}_i\left(k\right)+{\mathrm{\Φ}}_4{\stackrel{\→}{i}}_s\left(k\right)+{\mathrm{\Γ}}_3{\stackrel{\→}{v}}_s\left(k\right)+{\mathrm{\Γ}}_4{\stackrel{\→}{i}}_i\left(k\right)---\left(8\right)$

Wherein:

$A=\left[\begin{array}{cc}1& \frac{1}{C_f}\\ -\frac{1}{L_f}& -\frac{R_f}{L_f}\end{array}\right],B=\left[\begin{array}{cc}0& -\frac{1}{C_f}\\ \frac{1}{L_f}& 0\end{array}\right].$

Therefore, the prediction expression of the instantaneous reactive power of input side:

$Q^p(k+1)=|{\stackrel{\→}{v}}_{s\mathrm{\β}}^p(k+1){\stackrel{\→}{i}}_{s\mathrm{\α}}^p(k+1)+{\stackrel{\→}{v}}_{s\mathrm{\α}}^p(k+1){\stackrel{\→}{i}}_{s\mathrm{\β}}^p(k+1)|---\left(9\right)$

C. objective optimization

Objective optimization to variable is by a simple merit functions, selects the on off state making merit functions minimum For subsequent time optimum control.Merit functions expression formula is as follows:

$g={\mathrm{\λ}}_1|T_e^{*}-T_e^P(k+1)|+{\mathrm{\λ}}_2\left|\right|{{\stackrel{\→}{\mathrm{\ψ}}}_s}^{*}|-|{\stackrel{\→}{\mathrm{\ψ}}}_s^P(k+1)\left|\right|+{\mathrm{\λ}}_3|Q^p(k+1)-Q^{*}|---\left(10\right)$

λ 1, λ 2, λ 3, λ 4 and λ 5 are the weight coefficient of each variable.

For implementation model PREDICTIVE CONTROL, need current time supply voltage v_s, source current i_s, input voltage v_i, output Electric current i_o, five group of 13 road signal detection of rotating speed n, then need more various sensor and modulate circuit, causing sampling conditioning hardware electricity Road is relatively costly；Further, AD sampling time and digital filtering time delay, and the DSP process time is longer, can deteriorate MPC control further In method processed, operand is big, it is complicated to calculate, it is relatively low to control frequency and causes being difficult to hard-wired problem.Ultimately result in employing mesh It is long that front conventional controller based on DSP controls the cycle, and affects control performance and effect.

Summary of the invention

The present invention is directed to indirect matrix converter in background technology-asynchronous motor speed-regulating system model predictive control method deposit In the shortcoming that sampling is complicated, propose a kind of new simplification method of sampling-input voltage observation model predictive control strategy, utilize defeated Enter filter model and design and build input voltage observer to reduce systematic sampling；The method comprises the steps:

Step (1), analyzes sampled signal demand in the model predictive control method of IMC-IM governing system.

Particularly as follows: indirect matrix converter drives asynchronous machine bringing onto load to run, whole system is used model prediction control Method processed is controlled.This control method surveys the mesh of unity power factor for the stable speed governing and net realizing load side motor Mark, within each sampling period, selects motor electromagnetic torque, stator magnetic linkage and input reactive factor to carry out model prediction, And minimize to seek by merit functions and take optimized switching state.Concrete, 1) according to motor status equation, rotor magnetic linkage is entered Row observation, observation model needs the output voltage v of IMC_oWith output electric current i_oDetected value.2) set up stator magnetic linkage, electromagnetic torque and Input reactive power forecast model, wherein stator magnetic linkage, electromagnetic torque forecast model also need indirect matrix converter output voltage v_oWith output electric current i_o, output voltage v_oBy input voltage v_iDetected value and on off state restructuring draw；And it is pre-to input reactive power Survey model and need supply voltage v_s, source current i_s, input voltage v_i, input current i_i, and input current i_iBy output electric current i_o Draw with on off state restructuring.To sum up can obtain, the method needs supply voltage v_s, source current i_s, input voltage v_i, output electricity Stream i_o, rotating speed n totally five group of 13 road signal detection.The most various sensor and modulate circuit, can cause sampling conditioning hardware electricity Road is relatively costly；Further, AD sampling time and digital filtering time delay, and the DSP process time is longer, can deteriorate MPC control further In method processed, operand is big, it is complicated to calculate, it is relatively low to control frequency and causes being difficult to hard-wired problem.

Step (2), for the shortcoming of control method in analytical procedure (1), proposes to simplify sample circuit, first analyzes input Voltage sample effect in control method.

Analyze input voltage sampling effect in model prediction method and have three: 1. need the observation of input voltage to pass through Data recombination realizes the v to output voltage_oObservation, finally realize rotor flux observation, stator magnetic linkage and electromagnetic torque Prediction.2. need to input phase voltage v_iObservation realize the judgement of zoning, thus by stator current i_oObservation Data reconstruction, it is achieved input current i_iObservation, the final prediction realizing input reactive power.3. input voltage v is needed_iSight Measured value realizes source current i_sPrediction, meet input reactive power forecast model needs.

Step (3), according to input voltage effect in model predictive control method in step (2) the most 2., based on indirectly Matrix converter input filter modelling input voltage observer, substitutes traditional sampling.

Particularly as follows: according to the mathematical model of input filter, converted by the derivation of equation, v_iObservation supply voltage Represent with the observation of source current, the v of the output voltage under the on off state that now indirect matrix converter is different_o, pass through v_i Observation show, it is achieved that its effect in step (1) is 1.；Meanwhile, input voltage ripple within a cycle Shape is divided into six regions, passes through v_iObservation judge its region, determine its on off state, so that it is determined that respective switch Input current i under state_iObservation, it is achieved that its effect in step (1) is 2..

Step (4), according to input voltage in step (1) to the effect of reactive power forecast model 3., based on indirect matrix The mathematical model of changer input filter, rebuilds novel power supply electric current i_sForecast model, be used for inputting reactive power Prediction, eliminate input voltage input reactive power prediction demand.

Particularly as follows: according to the mathematical model of input filter, converted by the derivation of equation, v_iAvailable mains voltage and power supply The detected value of electric current represents, then brings the i of source current into_sPredictor formula, final realize input reactive power prediction.Therefore it is defeated Enter reactive power and only need supply voltage v_s, source current i_s, input current i_i, abandoned input voltage v_iIn input reactive power Effect in forecast model is 3..

Step (5), the observation of input voltage observer in step (3) and the idle merit of novel input in step (4) Rate forecast model is brought in model predictive control method, simplifies sampling.

Accompanying drawing explanation

Fig. 1 is indirect matrix converter-asynchronous motor speed-regulating system topology diagram.

Fig. 2 is virtual rectifier input voltage zoning plan.

Fig. 3 is virtual commutator effective on off state table.

Fig. 4 is virtual inverter effective on off state figure.

Fig. 5 is indirect matrix converter-asynchronous motor speed-regulating system Model Predictive Control block diagram.

Fig. 6 is indirect matrix converter input filter arrangement figure.

Fig. 7 is a matrix converter input voltage interval and input current i_i, output voltage v_oCorresponding table.

Fig. 8 is indirect matrix converter-asynchronous motor speed-regulating system Model Predictive Control frame based on input voltage observation Figure.

Detailed description of the invention

The technical problem to be solved is to provide a kind of indirect matrix converter Model Predictive Control and simplifies sampling Method, to overcome in model predictive control method sampling to cause, sampling conditioning hardware circuit is complicated, relatively costly, AD sampling time Between and extend during digital filtering, shortcoming that DSP processes time length.The present invention solves that the scheme that above-mentioned technical problem is used is Utilize the mathematical model of input filter, carry out derivation and the replacement of variable, devise novel input voltage observer and substitute biography System sample circuit, utilizes second order difference coefficient method to set up novel power supply electric current i simultaneously_sForecast model, thus realize input idle Power prediction decouples with input voltage, to reduce the PREDICTIVE CONTROL dependence to observation model.

1. the design of input voltage observer

Can from the conventional model predictive control strategy of the indirect matrix converter-asynchronous motor speed-regulating system shown in Fig. 5 To find out, it is the purpose of 1 to realize good operation speed governing and the input power factor of indirect matrix converter outlet side motor, Model Predictive Control strategy includes three parts: A, electric machine rotor flux observation；B, stator magnetic linkage, electromagnetic torque and input are idle Power prediction；C, merit functions optimization.In this control method, need the multiple signals of system are sampled, real at hardware More complicated sample circuit and numerous and diverse data operation can be caused in Xian.Therefore, the simplification of sample circuit is necessary trend.Many In the sampling of road, choosing input voltage vi is sample reduction target, and the two of the sampling purpose of input voltage are: 1. need input voltage Observation and on off state data recombination go out the v of output voltage_o, finally realize rotor flux observation, stator magnetic linkage and electricity The prediction of magnetic torque.2. need to input phase voltage v_iObservation realize the judgement of zoning, thus by stator current i_oSee Measured value and on off state data recombination go out input current i_i, the final prediction realizing input reactive power.The present invention is by utilizing The mathematical model of indirect matrix converter input filter, designs and builds input voltage v_iObserver, replaces traditional sampling electricity Road.

As shown in Figure 6, the input filter of indirect matrix converter is mainly composed in parallel by an inductance and an electric capacity, The high-frequency harmonic produced because of HF switch action because of indirect matrix converter can be filtered, in electrical network and changer connect be Indispensable part.Its second-order system known can be described as:

$\frac{d{\stackrel{\→}{i}}_s}{dt}=\frac{1}{L_f}{\stackrel{\→}{v}}_s-\frac{1}{L_f}{\stackrel{\→}{v}}_i-\frac{R_f}{L_f}{\stackrel{\→}{i}}_s---\left(11\right)$

$\frac{d{\stackrel{\→}{v}}_i}{dt}=\frac{1}{C_f}{\stackrel{\→}{i}}_s-\frac{1}{C_f}{\stackrel{\→}{i}}_i---\left(12\right)$

According to formula (11), Euler's formula is used it to be carried out discretization, as shown in formula (13):

L_fi_s(k)-L_fi_s(k-1)=T_sv_s(k-1)-T_Sv_i(k-1)-T_SR_fi_s(k-1) (13)

The collated equation below (14) that obtains:

$v_i(k-1)=v_s(k-1)-\frac{L_f}{T_s}{i}_s\left(k\right)+(\frac{L_f}{T_s}-R_f)i_s(k-1)---\left(14\right)$

Understand v_i(k-1) drawn by formula (14) observation.Due to input phase voltage v_iFor continuous signal, and sample frequency Higher, it is believed that v_i(k)≈v_i(k-1). i.e. shown in the input voltage observer such as formula (15) designed by the present invention:

$v_i\left(k\right)=v_i(k-1)=v_s(k-1)-\frac{L_f}{T_s}{i}_s\left(k\right)+(\frac{L_f}{T_s}-R_f)i_s(k-1)---\left(15\right)$

Between Fig. 7 is, matrix converter input voltage is interval with DC voltage v_dc, input current i_iMapping table.Based on upper State data observation formula (15), first pass through observer and observe input voltage v_iT_kThe value in moment；Then this is utilized to observe Value, it is determined that input voltage place is interval (1-6)；Finally realize the two of which purpose of observation input voltage: (1) is based on input electricity Pressure v_iObservation and place interval, derivation DC voltage v_dcValue, finally try to achieve output voltage v_oValue.(2) based on input Voltage place is interval, derivation input current i_iWith DC bus current I_dcCorresponding relation, wherein I_dcIt is by output electric current i_oNumber Obtain according to reconstruct.

Thus, input voltage observer as shown in Figure 8, the observation of input voltage instead of the sampling of former input voltage and exists The most 2. effect in model predictive control method, instead of tradition input voltage sampling, simplifies hardware sampling significantly Modulate circuit, thus extend to DSP when reducing AD sampling time and digital filtering and process the time.

2. novel power supply electric current i_sForecast model designs

3. the effect of input voltage sampled value is: from the indirect matrix converter-asynchronous motor speed-regulating system shown in Fig. 5 Conventional model predictive control strategy needs to be controlled input reactive power.In the predictor formula (9) to reactive power, need Want supply voltage v_sWith source current i_sForecast model；And at source current i_sPredictor formula (8) in need three groups of variablees electricity Source voltage v_s, source current i_s, input voltage v_iSampled value, the most at least need 9 tunnels sampling modulate circuits could realize.

The present invention proposes a kind of novel power supply electric current i_sForecast model, input voltage in direct abandoning tradition forecast model Sampled value effect, it is only necessary to source current i_sOne group of variable sampled value can dope i_s(k+1)。

Mathematical modulo pattern (11) based on input filter determines input voltage v_iExpression formula (16):

${\stackrel{\→}{v}}_i={\stackrel{\→}{v}}_s-R_f{\stackrel{\→}{i}}_s-L_f\frac{d{\stackrel{\→}{i}}_s}{dt}---\left(16\right)$

Wushu (16) is brought formula (12) formula into and is obtained equation below (17):

$C_f\frac{d(v_s-R_f{\stackrel{\→}{i}}_s-L_f\frac{d{\stackrel{\→}{i}}_s}{dt})}{dt}={\stackrel{\→}{i}}_s-{\stackrel{\→}{i}}_i---\left(17\right)$

In order to realize the prediction of source current, formula (17) is carried out discretization: to the first differential item in formula (17) Use difference coefficient (preceding paragraph Euler's formula) before single order to carry out discrete, second-order differential item use second-order central difference coefficient carry out discrete after:

${\stackrel{\→}{i}}_s^P(k+1)=\frac{(R_f{T}_s+2L_f-{T_S}^2/C_f){\stackrel{\→}{i}}_s\left(k\right)-L_f{\stackrel{\→}{i}}_s(k-1)+({T_S}^2/C_f){\stackrel{\→}{i}}_i^P\left(k\right)}{R_f{T}_s+L_f}---\left(18\right)$

Formula (18) is the forecast model of novel power supply electric current in the present invention, i in this formula_sAnd i (k-1)_sK () is electricity The sampled value of source electric current, and i_iK () is by output electric current i_oData reconstruction draws.Then wushu (18) bring into input idle In power prediction model formula (9), it is achieved indirect matrix converter is inputted the prediction of reactive power.Novel power supply electric current pre- The design surveying model achieves the variable prediction to the k+1 moment, has an advantage in that and can reduce PREDICTIVE CONTROL to observation model Rely on.

Claims (4)

1. an indirect matrix converter simplifies the model predictive control method sampled, it is characterised in that: to indirect matrixing Device-asynchronous motor speed-regulating system model predictive control method carries out sample reduction, makes full use of input filter model and designs Input voltage observer, to reduce system detection limit, reduces sample requirement；The method comprises the steps:

Step (1), analyzes sampled signal demand in the model predictive control method of IMC-IM governing system.

Particularly as follows: indirect matrix converter drives asynchronous machine bringing onto load to run, whole system is used Model Predictive Control side Method is controlled.This control method in order to realize stable speed governing and the target of net side unity power factor of load side motor, In each sampling period, select motor electromagnetic torque, stator magnetic linkage and input reactive factor to carry out model prediction, and pass through Merit functions minimizes to seek and takes optimized switching state.First according to motor status equation, rotor magnetic linkage is observed, sees Survey model and need the output voltage v of IMC_oWith output electric current i_oDetected value.Then set up stator magnetic linkage, electromagnetic torque and input nothing Merit power prediction model, wherein stator magnetic linkage, electromagnetic torque forecast model also need indirect matrix converter output voltage v_oWith defeated Go out electric current i_o, output voltage v_oBy input voltage v_iDetected value and on off state restructuring draw；And input reactive power forecast model Need supply voltage v_s, source current i_s, input voltage v_i, input current i_i, and input current i_iBy output electric current i_oAnd switch State restructuring draws.To sum up can obtain, the method needs supply voltage v_s, source current i_s, input voltage v_i, output electric current i_o, turn Speed n totally five group of 13 road signal detection.The most various sensor and modulate circuit, can cause sampling conditioning hardware circuit cost relatively High；Further, AD sampling time and digital filtering time delay, and the DSP process time is longer, can deteriorate in MPC control method further Operand is big, it is complicated to calculate, it is relatively low to control frequency and causes being difficult to hard-wired problem.

Step (2), for the shortcoming of control method in analytical procedure (1), proposes to simplify sample circuit, first analyzes input voltage Sampling effect in control method.

Step (3), according to input voltage effect in model predictive control method in step (2) the most 2., based on indirect matrix Changer input filter modelling input voltage observer, substitutes traditional sampling.

Step (4), according to input voltage in step (1) to the effect of reactive power forecast model 3., based on indirect matrixing The mathematical model of device input filter, rebuilds novel power supply electric current i_sForecast model, for inputting the pre-of reactive power Survey, eliminate the input voltage demand in input reactive power prediction.

Step (5), pre-to the observation of input voltage observer in step (3) and the novel input reactive power in step (4) Survey model and bring in model predictive control method, simplify sampling.

Indirect matrix converter the most according to claim 1 simplifies the model predictive control method of sampling, it is characterised in that: Step (2) has three particularly as follows: analyze input voltage sampling effect in model prediction method: 1. need the observation of input voltage Value realizes the v to output voltage by data recombination_oObservation, finally realize rotor flux observation, stator magnetic linkage and electricity The prediction of magnetic torque.2. need to input phase voltage v_iObservation realize the judgement of zoning, thus by stator current i_oSee The data reconstruction of measured value, it is achieved input current i_iObservation, the final prediction realizing input reactive power.3. input voltage is needed v_iObservation realize source current i_sPrediction, meet input reactive power forecast model needs.

Indirect matrix converter the most according to claim 1 simplifies the model predictive control method of sampling, it is characterised in that: Step (3) is particularly as follows: according to the mathematical model of input filter, convert by the derivation of equation, v_iObservation supply voltage Represent with the observation of source current, the v of the output voltage under the on off state that now indirect matrix converter is different_o, pass through v_i Observation show, it is achieved that its effect in step (1) is 1.；Meanwhile, input voltage ripple within a cycle Shape is divided into six regions, passes through v_iObservation judge its region, determine its on off state, so that it is determined that respective switch Input current i under state_iObservation, it is achieved that its effect in step (1) is 2..

Indirect matrix converter the most according to claim 1 simplifies the model predictive control method of sampling, it is characterised in that: Step (4) is particularly as follows: according to the mathematical model of input filter, convert by the derivation of equation, v_iAvailable mains voltage and power supply The detected value of electric current represents, then brings the i of source current into_sPredictor formula, final realize input reactive power prediction.Therefore it is defeated Enter reactive power and only need supply voltage v_s, source current i_s, input current i_i, abandoned input voltage v_iIn input reactive power Effect in forecast model is 3..