CN103259480B - Method and system for controlling doubly-fed wind generator speed sensor-less - Google Patents

Abstract

The invention provides a method and system for controlling a doubly-fed wind generator speed sensor-less. The method for controlling the doubly-fed wind generator speed sensor-less comprises the following steps that a stator voltage value, a stator current value and a rotor current value of a motor in a k moment are measured and converted according to a sampling period, rotor reference flux linkage in the k moment is calculated and acquired according to the stator voltage value and the stator current value in the k moment, a rotor flux linkage identification value in the k moment is calculated according to a rotor angular speed identification value, a rotor flux linkage identification value and the rotor current value in a k-1 moment, a rotor angular speed identification value in the k-1 moment is calculated and acquired according to the rotor reference flux linkage and the rotor current value in the k-1 moment and the rotor flux linkage identification value in the k moment, and wind generator closed loop feedback control is conducted according to the rotor angular speed identification value in the k-1 moment. By the adoption of a discretization algorithm, a speed identification method based on discrete slip form model reference self-adaptation is provided, and therefore a speed estimated value acquired by the method is accurate. The method for controlling the doubly-fed wind generator speed sensor-less is high in anti-jamming capacity and free of being affected by working conditions.

Description

Double-fed wind power generator Speed Sensorless Control Method and system

Technical field

The present invention relates to a kind of generator control technology, particularly relate to double-fed wind power generator Speed Sensorless Control Method and system.

Background technology

Double-fed wind power generator can carry out the parameter adjustments such as electromagnetic torque in the course of the work, generally carries out closed-loop control based on motor speed as feedback parameter.

No matter adopt which kind of control method, all need the rotating speed obtaining motor as feedback parameter.Traditional motor speed obtain manner arranges the rotating speed of mechanical pick-up device to motor to measure, but sensor measurement mode has many defects.The setting of mechanical pick-up device adds system cost and installation specification, and the measurement of rotating speed changes with the change of operating mode because of the parameter of electric machine, also to be subject to the impact of environmental factor, so there is comparatively big error, and speed error can increase with the increase of the factor such as temperature, vibration the impact of Electric Machine Control.Therefore, prior art has proposed the rotating speed acquisition methods of Speedless sensor.

So-called deadlock_free scheduling eliminates mechanical pick-up device, runs equation calculate rotating speed according to motor, calculate the rotating speed that obtains can small electromotor parameter with the change of temperature etc., and prior art and matured product at present.This technology is applied in wind generator system, with the impact of cope with bad environment on control effects, highly uses for reference.In Speed Sensorless Control Method, being adapted to control algolithm and accurately calculating the prerequisite that rotating speed is whole control program acquisition good result, is also the focus that those skilled in the art pay close attention to.

Summary of the invention

The invention provides a kind of double-fed wind power generator Speed Sensorless Control Method and system, obtaining scheme for optimizing motor speed, improving the accuracy that rotating speed calculates.

The invention provides a kind of double-fed wind power generator Speed Sensorless Control Method, comprising:

According to sampling period T _s, measure the stator voltage value of k moment motor, stator current value and rotor current, and be scaled to the stator voltage value U under alpha-beta coordinate system _{s, k}=[u _{s α, k}, u _{s β, k}] and stator current value I _{s, k}=[i _{s α, k}, i _{s β, k}], and rotor current i _{r α, k}, i _{r β, k}, wherein, subscript behalf stator, subscript r represents rotor, and k is sampling instant sequence number, and k=1,2...n, n are natural number;

According to k moment stator voltage value U _{s, k}=[u _{s α, k}, u _{s β, k}] and stator current value I _{s, k}=[i _{s α, k}, i _{s β, k}], obtain k moment rotor reference magnetic linkage based on following formulae discovery

${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=\frac{L_r}{L_m}({\mathrm{\Ψ}}_{s,k}-L_s\mathrm{\δ}{I}_{s,k})$

Wherein, ψ _{s, k}for according to k moment stator voltage value U _{s, k}=[u _{s α, k}, u _{s β, k}] the k moment stator magnetic linkage that obtains, for magnetic leakage factor, L _mfor the mutual inductance value of setting, L _sbe respectively the stator winding inductance value of setting, L _rfor the rotor windings inductance value of setting;

According to the rotor velocity identifier in k-1 moment rotor flux identifier and rotor current i _{r α, k-1}, i _{r β, k-1}, based on the rotor flux identifier in following formulae discovery k moment

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+[-{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\mathrm{\η}\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\α},k-1}]\·T_s$

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+[{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}-{\mathrm{\η}\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\β},k-1}]\·T_s$

Wherein, η is the inverse of rotor time constant;

According to the rotor reference magnetic linkage in k-1 moment with rotor current i _{r α, k-1}, i _{r β, k-1}, and the rotor flux identifier in k moment the identifier of the rotor velocity in k-1 moment is obtained based on following formulae discovery

${\widehat{\mathrm{\ω}}}_{r,k-1}=\frac{1-{\mathrm{\ηT}}_s}{T_s}\·\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}+\mathrm{\η}{L}_m\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{i}_{\mathrm{r\α},k-1}-{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{i}_{\mathrm{r\β},k-1}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}$

According to the identifier of the rotor velocity in k-1 moment carry out the control of wind-driven generator closed loop feedback, and the identifier carrying out the rotor velocity of next sampling instant according to said process calculates.

Present invention also offers a kind of double-fed wind power generator senseless control system, comprising:

Sampled measurements module, for according to sampling period T _s, measure the stator voltage value of k moment motor, stator current value and rotor current, and be scaled to the stator voltage value U under alpha-beta coordinate system _{s, k}=[u _{s α, k}, u _{s β, k}] and stator current value I _{s, k}=[i _{s α, k}, i _{s β, k}], and rotor current i _{r α, k}, i _{r β, k}, wherein, subscript behalf stator, subscript r represents rotor, and k is sampling instant sequence number, and k=1,2...n, n are natural number;

Reference Stator Flux Linkage computing module, for according to k moment stator voltage value U _{s, k}=[u _{s α, k}, u _{s β, k}] and stator current value I _{s, k}=[i _{s α, k}, i _{s β, k}], obtain k moment rotor reference magnetic linkage based on following formulae discovery

${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=[{\mathrm{\Ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}},{\mathrm{\Ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}]:$

${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=\frac{L_r}{L_m}({\mathrm{\Ψ}}_{s,k}-L_s\mathrm{\δ}{I}_{s,k})$

Wherein, ψ _{s, k}for according to k moment stator voltage value U _{s, k}=[u _{s α, k}, u _{s β, k}] the k moment stator magnetic linkage that obtains, for magnetic leakage factor, L _mfor the mutual inductance value of setting, L _sbe respectively the stator winding inductance value of setting, L _rfor the rotor windings inductance value of setting;

Magnetic linkage recognition module, for the rotor velocity identifier according to the k-1 moment rotor flux identifier with rotor current i _{r α, k-1}, i _{r β, k-1}, based on the rotor flux identifier in following formulae discovery k moment

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+[-{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\mathrm{\η}\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\α},k-1}]\·T_s$

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+[{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}-{\mathrm{\η}\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\β},k-1}]\·T_s$

Wherein, η is the inverse of rotor time constant;

Angular speed recognition module, for the rotor reference magnetic linkage according to the k-1 moment with rotor current i _{r α, k-1}, i _{r β, k-1}, and the rotor flux identifier in k moment the identifier of the rotor velocity in k-1 moment is obtained based on following formulae discovery

${\widehat{\mathrm{\ω}}}_{r,k-1}=\frac{1-{\mathrm{\ηT}}_s}{T_s}\·\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}+\mathrm{\η}{L}_m\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{i}_{\mathrm{r\α},k-1}-{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{i}_{\mathrm{r\β},k-1}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}$

Motor control module, for the identifier of the rotor velocity according to the k-1 moment carry out the control of wind-driven generator closed loop feedback, and the identifier carrying out the rotor velocity of next sampling instant according to said process calculates.

The present invention proposes a kind of control program of novel double-fed wind power generator Speedless sensor, use sliding formwork and model reference adaptive method, and take into full account the digitized feature of frequency converter control unit, use discretization algorithm, propose the Speed identification method based on discrete sliding mode model reference adaptive.Make the velocity estimation value obtained by this method, accurately, interference rejection ability is strong, and does not affect by operating mode.Calculate motor speed more accurate, and wind generator system can be made cost-saving compared to the mechanical pick-up device mode of testing the speed, also more adapt to adverse circumstances.

Accompanying drawing explanation

The flow chart of the double-fed wind power generator Speed Sensorless Control Method that Fig. 1 provides for the embodiment of the present invention one;

Fig. 2 is the algorithm structure block diagram obtaining rotor velocity identifier in the embodiment of the present invention;

The structural representation of the double-fed wind power generator senseless control system that Fig. 3 provides for the embodiment of the present invention two.

Embodiment

The flow chart of the double-fed wind power generator Speed Sensorless Control Method that Fig. 1 provides for the embodiment of the present invention one, the method is mainly used in carrying out closed loop feedback control to wind-driven generator based on rotating speed, and the present invention mainly pays close attention to the acquisition methods of motor speed, propose in the design of double-fed wind power generator Speedless sensor, estimation obtains the technology of motor speed.This control method can be performed by the control system of wind-driven generator, specifically comprises the steps:

Step 110, according to sampling period T _s, measure the stator voltage value of k moment motor, stator current value and rotor current, and be scaled to the stator voltage value U under alpha-beta coordinate system _{s, k}=[u _{s α, k}, u _{s β, k}], stator current value I _{s, k}=[i _{s α, k}, i _{s β, k}], and rotor current i _{r α, k}, i _{r β, k}, wherein, subscript behalf stator, subscript r represents rotor, and k is sampling instant sequence number, and k=1,2...n, n are natural number;

In practical operation, control system gathers the sampled value of each sampling instant one by one, U _sand I _sbe the vector value after conversion.Sampling period, according to tachometer value, is determined according to aromatic theorem.

Step 120, according to k moment stator voltage value U _{s, k}=[u _{s α, k}, u _{s β, k}] and stator current value I _{s, k}=[i _{s α, k}, i _{s β, k}], obtain k moment rotor reference magnetic linkage based on following formulae discovery

${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=\frac{L_r}{L_m}({\mathrm{\Ψ}}_{s,k}-L_s\mathrm{\δ}{I}_{s,k})$

Wherein, ψ _{s, k}for according to k moment stator voltage value U _{s, k}=[u _{s α, k}, u _{s β, k}] the k moment stator magnetic linkage that obtains, for magnetic leakage factor, L _mfor the mutual inductance value of setting, L _sbe respectively the stator winding inductance value of setting, L _rfor the rotor windings inductance value of setting;

In above-mentioned formula, the stator magnetic linkage in k moment can based on the stator voltage value U in k moment _scalculate and obtain, the stator magnetic linkage Ψ in k moment _sthe following formula discretization of preferred employing calculates and obtains:

Ψ _s＝∫e _sdt＝∫(U _s-I _sR _s)dt

Wherein, e _s, U _s, I _sbe respectively stator winding back-emf, stator voltage value and stator current value, R _sfor stator resistance.

Step 130, rotor velocity identifier according to the k-1 moment rotor flux identifier with rotor current i _{r α, k-1}, i _{r β, k-1}, based on the rotor flux identifier in following formulae discovery k moment

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+[-{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\mathrm{\η}\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\α},k-1}]\·T_s$

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+[{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}-{\mathrm{\η}\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\β},k-1}]\·T_s$

Wherein, η is the inverse of rotor time constant;

In above-mentioned steps 130, if the k moment is first sampling instant, then each measured value or identifier etc. in k-1 moment, all can adopt the initial value of acquiescence, such as, and the rotor current i in " 0 " moment _{r α, 0}, i _{r β, 0}the empirical value of 0 or other settings can be defaulted as.The value in other subsequent sampling moment can calculate with the value known according to a upper moment.

Step 140, rotor reference magnetic linkage according to the k-1 moment with rotor current i _{r α, k-1}, i _{r β, k-1}, and the rotor flux identifier in k moment the identifier of the rotor velocity in k-1 moment is obtained based on following formulae discovery

${\widehat{\mathrm{\ω}}}_{r,k-1}=\frac{1-{\mathrm{\ηT}}_s}{T_s}\·\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}+\mathrm{\η}{L}_m\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{i}_{\mathrm{r\α},k-1}-{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{i}_{\mathrm{r\β},k-1}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}$

Step 150, identifier according to the rotor velocity in k-1 moment carry out the control of wind-driven generator closed loop feedback, and the identifier carrying out the rotor velocity of next sampling instant according to said process calculates.

Because the sampling period is usually very little, so the rotor velocity between two sampling instants differs very little usually, the rotor velocity identifier in a upper moment can be considered as the rotor velocity of current time, carries out the air-blower control algorithm of current time.Can be applicable in the closed loop feedback control of double-fed wind generating c machine, be specifically applicable to various control strategy, the present embodiment does not limit air-blower control strategy.

The estimation equation of the present embodiment rotor angular speed identifier, realizes based on structure of block diagram shown in Fig. 2.The technical scheme of the present embodiment, proposes a kind of control method of novel double-fed wind power generator Speedless sensor.Use sliding formwork and model reference adaptive method, and take into full account the digitized feature of frequency converter control unit, use discretization algorithm, propose the Speed identification method based on discrete sliding mode model reference adaptive.Make the velocity estimation value obtained by this method, accurately, interference rejection ability is strong, and does not affect by operating mode.Calculate motor speed more accurate, and wind generator system can be made cost-saving compared to the mechanical pick-up device mode of testing the speed, also more adapt to adverse circumstances.

The estimation of the present embodiment rotor angular speed identifier, obtains based on model self-adapting method, by such as under type derivation acquisition:

First obtain the expression formula of the stator magnetic linkage that stator voltage value represents according to motor status equation, the computing formula of rotor flux can be calculated by stator magnetic linkage and indirectly obtain.Rotor flux expression formula can be used as the reference model of model reference adaptive, and this rotor flux expression formula is as follows:

${\mathrm{\Ψ}}_{\mathrm{r\α\β}}^{\mathrm{ref}}=\frac{L_r}{L_m}({\mathrm{\Ψ}}_s-L_s\mathrm{\δ}{I}_s)$

Then, the rotor flux expression formula represented by current model is as adjustable model, must there is difference in the rotor flux that the rotor flux calculated thus and voltage model obtain, choose the reasonable expression formula of this difference as error function, adjustable model expression formula is as follows:

$p\left[\begin{array}{c}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}\\ {\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}}\end{array}\right]=\left[\begin{array}{cc}-\mathrm{\η}& -{\widehat{\mathrm{\ω}}}_r\\ {\widehat{\mathrm{\ω}}}_r& -\mathrm{\η}\end{array}\right]\left[\begin{array}{c}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}\\ {\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}}\end{array}\right]+L_m\mathrm{\η}\left[\begin{array}{c}{i}_{\mathrm{r\α}}\\ i_{\mathrm{r\β}}\end{array}\right]$

Then, the necessary and sufficient condition set up by Popov (PoPoV) superstability theorem, getting proportional integral adaptive law is, K _p+ K _i/ s, obtains and as rotor velocity estimation formulas is:

${\widehat{\mathrm{\ω}}}_r=(K_p+K_i/s)[{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}}({\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}-{\mathrm{\ψ}}_{\mathrm{r\α}}^{\mathrm{ref}})-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}({\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}}-{\mathrm{\ψ}}_{\mathrm{r\β}}^{\mathrm{ref}})]$

$=K_p({\mathrm{\ψ}}_{\mathrm{r\β}}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}-{\mathrm{\ψ}}_{\mathrm{r\α}}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}})+K_i{\∫}_0^T({\mathrm{\ψ}}_{\mathrm{r\β}}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}-{\mathrm{\ψ}}_{\mathrm{r\α}}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}})\mathrm{dt}$

Choose if minor function is as error function thus:

$\mathrm{\ϵ}={\mathrm{\ψ}}_{\mathrm{r\β}}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}-{\mathrm{\ψ}}_{\mathrm{r\α}}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}}$

Above derivation can with reference to traditional MRAS algorithm.

In the present invention, choose above equation as sliding-mode surface function, the accessibility of being moved by sliding formwork derives the adaptive law that velocity estimation equivalent equation replaces above conventional method, and equation is as follows:

${\widehat{\mathrm{\ω}}}_r={\mathrm{\ω}}_r+\frac{\mathrm{\η}{L}_m{I}_{\mathrm{r\α}}({\mathrm{\ψ}}_{\mathrm{r\β}}^{\mathrm{ref}}-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}})+\mathrm{\η}{L}_m{I}_{\mathrm{r\β}}({\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}-{\mathrm{\ψ}}_{\mathrm{r\α}}^{\mathrm{ref}})}{({\widehat{\mathrm{\ψ}}}_{\mathrm{r\α}}{\mathrm{\ψ}}_{\mathrm{r\α}}^{\mathrm{ref}}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β}}{\mathrm{\ψ}}_{\mathrm{r\β}}^{\mathrm{ref}})}$

Above-mentioned rotor velocity identifier computing formula, as the foundation of discretization formulae discovery mode of the present invention, carries out discrete processes to each parameter of above-mentioned continuous formula, velocity estimation expression formula finally:

${\widehat{\mathrm{\ω}}}_{r,k-1}=\frac{1-{\mathrm{\ηT}}_s}{T_s}\·\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}+\mathrm{\η}{L}_m\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{i}_{\mathrm{r\α},k-1}-{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{i}_{\mathrm{r\β},k-1}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}$

The structural representation of the double-fed wind power generator senseless control system that Fig. 3 provides for the embodiment of the present invention two, this control system can be used for the control method that the execution embodiment of the present invention provides, and has corresponding functional module.This control system specifically comprises: sampled measurements module 310, Reference Stator Flux Linkage computing module 320, magnetic linkage recognition module 330, angular speed recognition module 340 and motor control module 350.

Wherein, sampled measurements module 310 is for according to sampling period T _s, measure the stator voltage value of k moment motor, stator current value and rotor current, and be scaled to the stator voltage value U under alpha-beta coordinate system _{s, k}=[u _{s α, k}, u _{s β, k}] and stator current value I _{s, k}=[i _{s α, k}, i _{s β, k}], and rotor current i _{r α, k}, i _{r β, k}, wherein, subscript behalf stator, subscript r represents rotor, and k is sampling instant sequence number, and k=1,2...n, n are natural number; Reference Stator Flux Linkage computing module 320, for according to k moment stator voltage value U _{s, k}=[u _{s α, k}, u _{s β, k}] and stator current value I _{s, k}=[i _{s α, k}, i _{s β, k}], obtain k moment rotor reference magnetic linkage based on following formulae discovery

${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=[{\mathrm{\Ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}},{\mathrm{\Ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}]:$

${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=\frac{L_r}{L_m}({\mathrm{\Ψ}}_{s,k}-L_s\mathrm{\δ}{I}_{s,k})$

Wherein, ψ _{s, k}for according to k moment stator voltage value U _{s, k}=[u _{s α, k}, u _{s β, k}] the k moment stator magnetic linkage that obtains, for magnetic leakage factor, L _mfor the mutual inductance value of setting, L _sbe respectively the stator winding inductance value of setting, L _rfor the rotor windings inductance value of setting;

Magnetic linkage recognition module 330 is for the rotor velocity identifier according to the k-1 moment rotor flux identifier with rotor current i _{r α, k-1}, i _{r β, k-1}, based on the rotor flux identifier in following formulae discovery k moment

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+[-{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\mathrm{\η}\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\α},k-1}]\·T_s$

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+[{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}-{\mathrm{\η}\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\β},k-1}]\·T_s$

Wherein, η is the inverse of rotor time constant;

Angular speed recognition module 340 is for the rotor reference magnetic linkage according to the k-1 moment with rotor current i _{r α, k-1}, i _{r β, k-1}, and the rotor flux identifier in k moment the identifier of the rotor velocity in k-1 moment is obtained based on following formulae discovery

${\widehat{\mathrm{\ω}}}_{r,k-1}=\frac{1-{\mathrm{\ηT}}_s}{T_s}\·\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}+\mathrm{\η}{L}_m\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{i}_{\mathrm{r\α},k-1}-{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{i}_{\mathrm{r\β},k-1}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}$

Motor control module 350 is for the identifier of the rotor velocity according to the k-1 moment carry out the control of wind-driven generator closed loop feedback, and the identifier carrying out the rotor velocity of next sampling instant according to said process calculates.

In above-mentioned control system: the stator magnetic linkage Ψ in k moment _sbe preferably based on following formula discretization and calculate acquisition: Ψ _s=∫ e _sdt=∫ (U _s-I _sr _s) dt.Wherein, e _s, U _s, I _sbe respectively stator winding back-emf, stator voltage value and stator current value, R _sfor stator resistance.

The embodiment of the present invention is intended to improve wind turbine generator adaptability in the presence of a harsh environment and stability, improves the accuracy controlled.After removing mechanical pick-up device, motor speed value method according to the present invention is accurately estimated.On traditional MRAS and sliding mode control theory basis, propose a kind of one-dimensional discrete sliding mode model self-adapted control method (DTSM MRAS), first algorithm utilizes traditional MRAS method to obtain identification magnetic linkage, POPOV theorem is adopted to obtain error function as sliding-mode surface, buffet the control of introducing Discrete-time Sliding Mode for improving synovial membrane, the proportional plus integral control link substituted by the sliding-mode surface function after the process of one-dimensional departure process in conventional method realizes the estimation to rotating speed.

The present invention can obtain accurate velocity estimation value, realizes more accurate Systematical control, and the acquisition of rotating speed is not by the impact of external environment condition, and antijamming capability is strong.

The method of rotating speed is measured compared to velocity transducer; the embodiment of the present invention can reduce the holding wire of laying; and current blower fan overspeed protection is the detection to hub rotation speed; again according to register ratio; be converted to generator speed; such indirect inspection; the error caused is relatively large; so the scope that the arranges surplus of present speed protection value is larger; can not accomplish accurately, after adopting technology of the present invention, directly to calculate rotating speed by motor operating parameter; precision is good, can do more accurate speed protection.And speed monitoring and the hardware protection equipment of relevant costliness can be saved, directly provide protection act by Control System Software.

One of ordinary skill in the art will appreciate that: all or part of step realizing above-mentioned each embodiment of the method can have been come by the hardware that program command is relevant.Aforesaid program can be stored in a computer read/write memory medium.This program, when performing, performs the step comprising above-mentioned each embodiment of the method; And aforesaid storage medium comprises: ROM, RAM, magnetic disc or CD etc. various can be program code stored medium.

Last it is noted that above each embodiment is only in order to illustrate technical scheme of the present invention, be not intended to limit; Although with reference to foregoing embodiments to invention has been detailed description, those of ordinary skill in the art is to be understood that: it still can be modified to the technical scheme described in foregoing embodiments, or carries out equivalent replacement to wherein some or all of technical characteristic; And these amendments or replacement, do not make the essence of appropriate technical solution depart from the scope of various embodiments of the present invention technical scheme.

Claims (2)

1. a double-fed wind power generator Speed Sensorless Control Method, is characterized in that, comprising:

According to sampling period T _s, measure the stator voltage value of k moment motor, stator current value and rotor current, and be scaled to the stator voltage value U under alpha-beta coordinate system _s,k=[u _{s α, k}, u _{s β, k}] and stator current value I _s,k=[i _{s α, k}, i _{s β, k}], and rotor current i _{r α, k}, i _{r β, k}, wherein, subscript behalf stator, subscript r represents rotor, and k is sampling instant sequence number, k=1,2 ... n, n are natural number;

According to k moment stator voltage value U _s,k=[u _{s α, k}, u _{s β, k}] and stator current value I _s,k=[i _{s α, k}, i _{s β, k}], obtain k moment rotor reference magnetic linkage based on following formulae discovery

${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=\frac{L_r}{L_m}({\mathrm{\Ψ}}_{s,k}-L_s\mathrm{\δ}{I}_{s,k})$

Wherein, Ψ _s,kfor according to k moment stator voltage value U _s,k=[u _{s α, k}, u _{s β, k}] the k moment stator magnetic linkage that obtains, for magnetic leakage factor, L _mfor the mutual inductance value of setting, L _sbe respectively the stator winding inductance value of setting, L _rfor the rotor windings inductance value of setting;

According to the rotor velocity identifier in k-1 moment rotor flux identifier with rotor current i _{r α, k-1}, i _{r β, k-1}, based on the rotor flux identifier in following formulae discovery k moment

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+[-{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-\mathrm{\η}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\α},k-1}]\·T_s$

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+[{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}-\mathrm{\η}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\β},k-1}]\·T_s$

Wherein, η is the inverse of rotor time constant;

According to the rotor reference magnetic linkage in k-1 moment with rotor current i _{r α, k-1}, i _{r β, k-1}, and the rotor flux identifier in k moment the identifier of the rotor velocity in k-1 moment is obtained based on following formulae discovery

${\widehat{\mathrm{\ω}}}_{r,k-1}=\frac{1-\mathrm{\η}{T}_s}{T_s}\·\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}+\mathrm{\η}{L}_m\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{i}_{\mathrm{r\α},k-1}-{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{i}_{\mathrm{r\β},k-1}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}$

According to the identifier of the rotor velocity in k-1 moment carry out the control of wind-driven generator closed loop feedback, and the identifier carrying out the rotor velocity of next sampling instant according to said process calculates;

The stator magnetic linkage Ψ in k moment _scalculate based on following formula discretization and obtain:

Ψ _s＝∫e _sdt＝∫(U _s-I _sR _s)dt

Wherein, e _s, U _s, I _sbe respectively stator winding back-emf, stator voltage value and stator current value, R _sfor stator resistance.

2. a double-fed wind power generator senseless control system, is characterized in that, comprising:

Sampled measurements module, for according to sampling period T _s, measure the stator voltage value of k moment motor, stator current value and rotor current, and be scaled to the stator voltage value U under alpha-beta coordinate system _s,k=[u _{s α, k}, u _{s β, k}] and stator current value I _s,k=[i _{s α, k}, i _{s β, k}], and rotor current i _{r α, k}, i _{r β, k}, wherein, subscript behalf stator, subscript r represents rotor, and k is sampling instant sequence number, k=1,2 ... n, n are natural number;

Reference Stator Flux Linkage computing module, for according to k moment stator voltage value U _s,k=[u _{s α, k}, u _{s β, k}] and stator current value I _s,k=[i _{s α, k}, i _{s β, k}], obtain k moment rotor reference magnetic linkage based on following formulae discovery ${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=[{\mathrm{\Ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}},{\mathrm{\Ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}]:$

${\mathrm{\Ψ}}_{\mathrm{r\α\β},k}^{\mathrm{ref}}=\frac{L_r}{L_m}({\mathrm{\Ψ}}_{s,k}-L_s\mathrm{\δ}{I}_{s,k})$

Wherein, Ψ _s,kfor according to k moment stator voltage value U _s,k=[u _{s α, k}, u _{s β, k}] the k moment stator magnetic linkage that obtains, for magnetic leakage factor, L _mfor the mutual inductance value of setting, L _sbe respectively the stator winding inductance value of setting, L _rfor the rotor windings inductance value of setting;

Magnetic linkage recognition module, for the rotor velocity identifier according to the k-1 moment rotor flux identifier with rotor current i _{r α, k-1}, i _{r β, k-1}, based on the rotor flux identifier in following formulae discovery k moment

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+[-{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-\mathrm{\η}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\α},k-1}]\·T_s$

${\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k}={\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}+[{\widehat{\mathrm{\ω}}}_{r,k-1}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}-\mathrm{\η}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+\mathrm{\η}{L}_m{i}_{\mathrm{r\β},k-1}]\·T_s$

Wherein, η is the inverse of rotor time constant;

Angular speed recognition module, for the rotor reference magnetic linkage according to the k-1 moment with rotor current i _{r α, k-1}, i _{r β, k-1}, and the rotor flux identifier in k moment the identifier of the rotor velocity in k-1 moment is obtained based on following formulae discovery

${\widehat{\mathrm{\ω}}}_{r,k-1}=\frac{1-\mathrm{\η}{T}_s}{T_s}\·\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}-{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}+\mathrm{\η}{L}_m\frac{{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}{i}_{\mathrm{r\α},k-1}-{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{i}_{\mathrm{r\β},k-1}}{{\mathrm{\ψ}}_{\mathrm{r\α},k}^{\mathrm{ref}}{\widehat{\mathrm{\ψ}}}_{\mathrm{r\α},k-1}+{\widehat{\mathrm{\ψ}}}_{\mathrm{r\β},k-1}{\mathrm{\ψ}}_{\mathrm{r\β},k}^{\mathrm{ref}}}$

Motor control module, for the identifier of the rotor velocity according to the k-1 moment carry out the control of wind-driven generator closed loop feedback, and the identifier carrying out the rotor velocity of next sampling instant according to said process calculates;

The stator magnetic linkage Ψ in k moment _scalculate based on following formula discretization and obtain:

Ψ _s＝∫e _sdt＝∫(U _s-I _sR _s)dt

Wherein, e _s, U _s, I _sbe respectively stator winding back-emf, stator voltage value and stator current value, R _sfor stator resistance.