CN103259480A - 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 Speedless sensor control method and system

Technical field

The present invention relates to a kind of generator control technology, relate in particular to double-fed wind power generator Speedless sensor control method and system.

Background technology

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

No matter adopt which kind of control method, all need to obtain rotating speed of motor as feedback parameter.Traditional motor speed obtain manner is mechanical pick-up device to be set rotating speed of motor is measured, but the sensor measurement mode has many defectives.Arranging of mechanical pick-up device increased system cost and installation specification, and the measurement of rotating speed changes because of the variation of the parameter of electric machine with operating mode, also to be subjected to Effect of Environmental, so exist than mistake, and speed error increases with the increase of factors such as temperature, vibration the meeting that influences of Electric Machine Control.Therefore, prior art has proposed the rotating speed acquisition methods of Speedless sensor.

So-called Speedless sensor technology is to have cancelled mechanical pick-up device, calculates rotating speed according to motor operation equation, but calculates the rotating speed small electromotor parameter that obtains with the variation of temperature etc., and prior art and matured product at present.This technology is applied in the wind generator system, with the influence of cope with bad environment to the control effect, is worth very much using for reference.In the Speedless sensor control method, be adapted to control algolithm and accurately calculate the prerequisite that rotating speed is The whole control scheme acquisition good result, also be 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 Speedless sensor control method and system, be used for optimizing motor speed and obtain scheme, improve the accuracy that rotating speed calculates.

The invention provides a kind of double-fed wind power generator Speedless sensor control method, comprising:

According to sampling period T _s, measure k stator voltage value, stator current value and the rotor current value of motor constantly, and be scaled to the stator voltage value U under the 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 value i _{R α, k}, i _{R β, k}, wherein, subscript s represents stator, and subscript r represents rotor, and k is the 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 with reference to magnetic linkage based on following formula calculating

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

Wherein, ψ _{S, k}For according to k stator voltage value U constantly _{S, k}=[u _{S α, k}, u _{S β, k}] k that obtains stator magnetic linkage constantly, Be magnetic leakage factor, L _mBe the mutual inductance value of setting, L _sBe respectively the stator winding inductance value of setting, L _rBe the rotor winding inductance value of setting;

According to k-1 rotor velocity identifier constantly

The rotor flux identifier and

Rotor current value i _{R α, k-1}, i _{R β, k-1}, calculate k rotor flux identifier constantly based on following formula

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

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

Wherein, η is the inverse of rotor time constant;

According to k-1 rotor constantly with reference to magnetic linkage

With rotor current value i _{R α, k-1}, i _{R β, k-1}, and k rotor flux identifier constantly

Calculate the identifier that obtains k-1 rotor velocity constantly based on following formula

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

Identifier according to k-1 rotor velocity constantly

Carry out the control of wind-driven generator closed loop feedback, and carry out the identifier calculating of the rotor velocity of next sampling instant according to said process.

The present invention also provides a kind of double-fed wind power generator Speedless sensor control system, comprising:

The sampled measurements module is used for according to sampling period T _s, measure k stator voltage value, stator current value and the rotor current value of motor constantly, and be scaled to the stator voltage value U under the 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 value i _{R α, k}, i _{R β, k}, wherein, subscript s represents stator, and subscript r represents rotor, and k is the sampling instant sequence number, k=1,2...n, n are natural number;

With reference to the magnetic linkage computing module, be used 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 with reference to magnetic linkage based on following formula calculating

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

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

Wherein, ψ _{S, k}For according to k stator voltage value U constantly _{S, k}=[u _{S α, k}, u _{S β, k}] k that obtains stator magnetic linkage constantly,

Be magnetic leakage factor, L _mBe the mutual inductance value of setting, L _sBe respectively the stator winding inductance value of setting, L _rBe the rotor winding inductance value of setting;

The magnetic linkage recognition module is used for the rotor velocity identifier constantly according to k-1 The rotor flux identifier

With rotor current value i _{R α, k-1}, i _{R β, k-1}, calculate k rotor flux identifier constantly based on following formula

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

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

Wherein, η is the inverse of rotor time constant;

The angular speed recognition module is used for according to k-1 rotor constantly with reference to magnetic linkage

With rotor current value i _{R α, k-1}, i _{R β, k-1}, and k rotor flux identifier constantly

Calculate the identifier that obtains k-1 rotor velocity constantly based on following formula

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

Motor control module is used for the identifier according to k-1 rotor velocity constantly

Carry out the control of wind-driven generator closed loop feedback, and carry out the identifier calculating of the rotor velocity of next sampling instant according to said process.

The present invention proposes a kind of control scheme of novel double-fed wind power generator Speedless sensor, use sliding formwork and model reference adaptive method, and take into full account the digitized characteristics in Frequency Converter Control unit, use the discretization algorithm, proposed the Speed identification method based on the discrete sliding mode model reference adaptive.The feasible velocity estimation value that obtains by this method, accurately, interference rejection ability is strong, and not influenced by operating mode.It is more accurate to calculate motor speed, and can make wind generator system save cost than the mechanical pick-up device mode of testing the speed, and also more adapts to adverse circumstances.

Description of drawings

The flow chart of the double-fed wind power generator Speedless sensor control method that Fig. 1 provides for the embodiment of the invention one;

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

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

Embodiment

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

Step 110, according to sampling period T _s, measure k stator voltage value, stator current value and the rotor current value of motor constantly, and be scaled to the stator voltage value U under the 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 value i _{R α, k}, i _{R β, k}, wherein, subscript s represents stator, and subscript r represents rotor, and k is the sampling instant sequence number, k=1,2...n, n are natural number;

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

Step 120, according to k stator voltage value U constantly _{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 with reference to magnetic linkage based on following formula calculating

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

Wherein, ψ _{S, k}For according to k stator voltage value U constantly _{S, k}=[u _{S α, k}, u _{S β, k}] k that obtains stator magnetic linkage constantly,

Be magnetic leakage factor, L _mBe the mutual inductance value of setting, L _sBe respectively the stator winding inductance value of setting, L _rBe the rotor winding inductance value of setting;

In above-mentioned formula, k stator magnetic linkage constantly can be based on k stator voltage value U constantly _sCalculate and obtain k stator magnetic linkage Ψ constantly _sThe following formula discretization of preferred employing is calculated and is obtained:

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 _sBe stator resistance.

Step 130, according to k-1 rotor velocity identifier constantly

The rotor flux identifier

With rotor current value i _{R α, k-1}, i _{R β, k-1}, calculate k rotor flux identifier constantly based on following formula

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

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

Wherein, η is the inverse of rotor time constant;

In above-mentioned steps 130, if k be first sampling instant constantly, k-1 each measured value or identifier etc. constantly then all can adopt the initial value of acquiescence, for example, and the rotor current value i in " 0 " moment _{R α, 0}, i _{R β, 0}Can be defaulted as 0 or the empirical value of other settings.Other subsequent sampling value constantly can be calculated with the value of knowing according to last one constantly.

Step 140, according to k-1 rotor constantly with reference to magnetic linkage With rotor current value i _{R α, k-1}, i _{R β, k-1}, and k rotor flux identifier constantly

Calculate the identifier that obtains k-1 rotor velocity constantly based on following formula

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

Step 150, according to the identifier of k-1 rotor velocity constantly

Carry out the control of wind-driven generator closed loop feedback, and carry out the identifier calculating of the rotor velocity of next sampling instant according to said process.

Because the sampling period is very little usually, so that the rotor velocity between two sampling instants differs usually is very little, last one constantly rotor velocity identifier can be considered as the rotor velocity of current time, carry out the blower fan control algolithm of current time.Can be applicable in the closed loop feedback control of double-fed wind generating c machine, specifically applicable to the various control strategy, present embodiment does not limit the blower fan control strategy.

The estimation equation of present embodiment rotor angular speed identifier is based on that structure of block diagram shown in Figure 2 realizes.The technical scheme of present embodiment has proposed 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 characteristics in Frequency Converter Control unit, use the discretization algorithm, proposed the Speed identification method based on the discrete sliding mode model reference adaptive.The feasible velocity estimation value that obtains by this method, accurately, interference rejection ability is strong, and not influenced by operating mode.It is more accurate to calculate motor speed, and can make wind generator system save cost than the mechanical pick-up device mode of testing the speed, and also more adapts to adverse circumstances.

The estimation of present embodiment rotor angular speed identifier obtains the acquisition of can deriving in the following way based on model self-adapting method:

At first obtain the expression formula of the stator magnetic linkage of stator voltage value representation according to the motor status equation, the computing formula of rotor flux can be calculated by stator magnetic linkage and obtain indirectly.The 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 of being represented by current model is as adjustable model, must there be difference in the rotor flux that the rotor flux that calculates thus and voltage model obtain, chooses the reasonable expression formula of this difference as error function, and the 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, by Popov (PoPoV) superstability theorem Necessary and sufficient conditions, get the proportional integral adaptive law and be K _p+ K _i/ s gets as the rotor velocity estimation formulas and 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 thus as minor function as error function:

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

Above derivation can be with reference to traditional MRAS algorithm.

In the present invention, choose above equation as the sliding-mode surface function, derive the adaptive law that the velocity estimation equivalent equation replaces above conventional method by the accessibility of sliding formwork motion, 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 is carried out discrete processes as the foundation of discretization formula account form of the present invention to each parameter of above-mentioned continuous formula, the velocity estimation expression formula that gets final product 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 Speedless sensor control system that Fig. 3 provides for the embodiment of the invention two, this control system can be used for carrying out the control method that the embodiment of the invention provides, and has corresponding functional module.This control system specifically comprises: sampled measurements module 310, with reference to magnetic 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 used for according to sampling period T _s, measure k stator voltage value, stator current value and the rotor current value of motor constantly, and be scaled to the stator voltage value U under the 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 value i _{R α, k}, i _{R β, k}, wherein, subscript s represents stator, and subscript r represents rotor, and k is the sampling instant sequence number, k=1,2...n, n are natural number; With reference to magnetic linkage computing module 320, be used 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 with reference to magnetic linkage based on following formula calculating

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

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

Wherein, ψ _{S, k}For according to k stator voltage value U constantly _{S, k}=[u _{S α, k}, u _{S β, k}] k that obtains stator magnetic linkage constantly,

Be magnetic leakage factor, L _mBe the mutual inductance value of setting, L _sBe respectively the stator winding inductance value of setting, L _rBe the rotor winding inductance value of setting;

Magnetic linkage recognition module 330 is used for the rotor velocity identifier constantly according to k-1

The rotor flux identifier

With rotor current value i _{R α, k-1}, i _{R β, k-1}, calculate k rotor flux identifier constantly based on following formula

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

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

Wherein, η is the inverse of rotor time constant;

Angular speed recognition module 340 is used for according to k-1 rotor constantly with reference to magnetic linkage

With rotor current value i _{R α, k-1}, i _{R β, k-1}, and k rotor flux identifier constantly

Calculate the identifier that obtains k-1 rotor velocity constantly based on following formula

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

The identifier that motor control module 350 is used for according to k-1 rotor velocity constantly Carry out the control of wind-driven generator closed loop feedback, and carry out the identifier calculating of the rotor velocity of next sampling instant according to said process.

In the above-mentioned control system: k stator magnetic linkage Ψ constantly _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 _sBe stator resistance.

The embodiment of the invention is intended to improve adaptability and the stability of wind turbine generator under adverse circumstances, improves the accuracy of control.After removing mechanical pick-up device, motor speed value the method according to this invention is accurately estimated.On traditional MRAS and sliding mode control theory basis, a kind of one-dimensional discrete sliding mode model adaptation control method (DTSM MRAS) has been proposed, algorithm at first utilizes traditional MRAS method to obtain the identification magnetic linkage, adopt the POPOV theorem to obtain error function as sliding-mode surface, buffet the control of introducing discrete time sliding formwork for improving synovial membrane, the proportional plus integral control link in the alternative conventional method of sliding-mode surface function after the one-dimensional departure process is handled realizes the estimation to rotating speed.

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

Measure the method for rotating speed than velocity transducer; the embodiment of the invention can reduce the holding wire of laying; and present blower fan overspeed protection is the detection to hub rotation speed; again according to register ratio; be converted to generator speed; indirect measurement like this; the error that causes is relatively large; so the scope that the arranges surplus of present speed protection value is bigger; can not accomplish accurately, adopt technology of the present invention after, directly calculate rotating speed by motor operating parameter; precision is good, can do more accurate speed protection.And can save speed monitoring and the hardware protection equipment of relevant costliness, directly provide the protection action by control system software.

One of ordinary skill in the art will appreciate that: all or part of step that realizes above-mentioned each method embodiment can be finished by the relevant hardware of program command.Aforesaid program can be stored in the computer read/write memory medium.This program is carried out the step that comprises above-mentioned each method embodiment when carrying out; And aforesaid storage medium comprises: various media that can be program code stored such as ROM, RAM, magnetic disc or CD.

It should be noted that at last: above each embodiment is not intended to limit only in order to technical scheme of the present invention to be described; Although the present invention has been described in detail with reference to aforementioned each embodiment, those of ordinary skill in the art is to be understood that: it still can be made amendment to the technical scheme that aforementioned each embodiment puts down in writing, and perhaps some or all of technical characterictic wherein is equal to replacement; And these modifications or replacement do not make the essence of appropriate technical solution break away from the scope of various embodiments of the present invention technical scheme.

Claims (4)

1. a double-fed wind power generator Speedless sensor control method is characterized in that, comprising:

According to sampling period T _s, measure k stator voltage value, stator current value and the rotor current value of motor constantly, and be scaled to the stator voltage value U under the 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 value i _{R α, k}, i _{R β, k}, wherein, subscript s represents stator, and subscript r represents rotor, and k is the 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 with reference to magnetic linkage based on following formula calculating

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

Wherein, ψ _{S, k}For according to k stator voltage value U constantly _{S, k}=[u _{S α, k}, u _{S β, k}] k that obtains stator magnetic linkage constantly,

Be magnetic leakage factor, L _mBe the mutual inductance value of setting, L _sBe respectively the stator winding inductance value of setting, L _rBe the rotor winding inductance value of setting;

According to k-1 rotor velocity identifier constantly The rotor flux identifier

Know rotor current value i _{R α, k-1}, i _{R β, k-1}, calculate k rotor flux identifier constantly based on following formula

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

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

Wherein, η is the inverse of rotor time constant;

According to k-1 rotor constantly with reference to magnetic linkage

With rotor current value i _{R α, k-1}, i _{R β, k-1}, and k rotor flux identifier constantly

Calculate the identifier that obtains k-1 rotor velocity constantly based on following formula

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

Identifier according to k-1 rotor velocity constantly

Carry out the control of wind-driven generator closed loop feedback, and carry out the identifier calculating of the rotor velocity of next sampling instant according to said process.

2. double-fed wind power generator Speedless sensor control method according to claim 1 is characterized in that: k stator magnetic linkage Ψ constantly _sCalculate acquisition based on following formula discretization:

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, Rs is stator resistance.

3. a double-fed wind power generator Speedless sensor control system is characterized in that, comprising:

The sampled measurements module is used for according to sampling period T _s, measure k stator voltage value, stator current value and the rotor current value of motor constantly, and be scaled to the stator voltage value U under the 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 value i _{R α, k}, i _{R β, k}, wherein, subscript s represents stator, and subscript r represents rotor, and k is the sampling instant sequence number, k=1,2...n, n are natural number;

With reference to the magnetic linkage computing module, be used 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 with reference to magnetic linkage based on following formula calculating

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

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

Wherein, ψ _{S, k}For according to k stator voltage value U constantly _{S, k}=[u _{S α, k}, u _{S β, k}] k that obtains stator magnetic linkage constantly,

Be magnetic leakage factor, L _mBe the mutual inductance value of setting, L _sBe respectively the stator winding inductance value of setting, L _rBe the rotor winding inductance value of setting;

The magnetic linkage recognition module is used for the rotor velocity identifier constantly according to k-1

The rotor flux identifier

With rotor current value i _{R α, k-1}, i _{R β, k-1}, calculate k rotor flux identifier constantly based on following formula

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

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

Wherein, η is the inverse of rotor time constant;

The angular speed recognition module, be used for according to k-1 rotor constantly with reference to magnetic linkage and

With rotor current value i _{R α, k-1}, i _{R β, k-1}, and k rotor flux identifier constantly

Calculate the identifier that obtains k-1 rotor velocity constantly based on following formula

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

Motor control module is used for the identifier according to k-1 rotor velocity constantly

Carry out the control of wind-driven generator closed loop feedback, and carry out the identifier calculating of the rotor velocity of next sampling instant according to said process.

4. double-fed wind power generator Speedless sensor control system according to claim 3 is characterized in that: k stator magnetic linkage Ψ constantly _sCalculate acquisition based on following formula discretization:

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 _sBe stator resistance.

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