CN103603771B - A kind of wind power generating set optimal wind energy catching method - Google Patents

Abstract

The invention discloses a kind of wind power generating set optimal wind energy catching method, in conjunction with search by hill climbing method, the method, based on rotational speed and torque table method, determines that combination of wind-driven generator fits rotating speed, it is achieved optimal wind energy captures；, in conjunction with long-time data statistics, being finely adjusted rotational speed and torque table, shortening system determines the time of optimum speed, adds unit generation amount meanwhile；The present invention is simple, amount of calculation is little, and adds up the unit final torque disturbance value to applying under the most corresponding rotating speed, and when torque adjusts to specific direction for a long time, rotational speed and torque table is finely adjusted by controller, reduces and finds the optimized rotating speed time.

Description

A kind of wind power generating set optimal wind energy catching method

Technical field

The present invention relates to wind-powered electricity generation field, particularly relate to a kind of wind power generating set optimal wind energy catching method.

Background technology

Wind-power electricity generation process is: wind power generating set absorbs wind energy by blade, wind energy is converted to mechanical energy and passes through Main shaft, gear-box (part of generating units does not has) pass to electromotor, and electromotor converts mechanical energy into electric energy, by current transformer, case Formula transformer station delivers the power to electrical network.

Wind power generating set output electric energy number capture the how rare close relationship of wind energy with it.Wind power generating set When being operated in below rated wind speed, improve unit Wind energy extraction ability, unit can be made to capture more wind energy, by more wind Electric energy can be converted to, improve the generated energy of unit.

Summary of the invention

The purpose of the present invention is contemplated to solve the problems referred to above, it is provided that a kind of wind power generating set optimal wind energy capture side Method, in conjunction with search by hill climbing method, the method, based on rotary speed-torque table method, determines that combination of wind-driven generator fits rotating speed, it is achieved Good Wind energy extraction；, in conjunction with long-time data statistics, being finely adjusted rotary speed-torque table, shortening system determines optimum speed meanwhile Time, increase unit and be operated in time of optimal wind energy trapped state, thus add unit generation amount.

The operation principle of the present invention is: absorb mechanical output and wind that wind energy produces when wind power generating set is properly functioning Speed relation is as follows:

$P_m=\frac{1}{2}{\mathrm{\ρAC}}_P{V}^3---\left(1\right)$

In formula: P_mFor mechanical output, ρ is atmospheric density, and A is wind wheel sweeping area, C_PFor power coefficient, V is wind Speed.

In unit running process, in (1) formula, ρ, A are fixed value, are not affected by unit allocation, thus, it can be known that at wind speed V mono- In the case of Ding, the approach improving wind power generating set capture wind energy improves power coefficient C exactly_P.Power coefficient C_P With ratio (tip speed ratio) λ of wind generator set blade top linear velocity Yu wind speed, pitch angle beta has substantial connection；Specified Time below wind speed, pitch angle beta remains 0, can realize optimal wind energy capture by adjusting tip speed ratio λ.

Under normal circumstances, the first meeting of wind power generating set design goes out the optimal tip-speed ratio of unit by simulation calculation, at unit In actual operation, control the actual tip-speed ratio of unit and infinitely can realize optimal wind energy capture near optimal tip-speed ratio.

To achieve these goals, the present invention adopts the following technical scheme that

A kind of wind power generating set optimal wind energy catching method, comprises the following steps:

(1) calculate the relation curve of wind-driven generator group wind-wheel rotating speed and generator torque based on optimal tip-speed ratio, i.e. turn Speed-torque indicator；

(2) the controller solidification rotary speed-torque table of wind power generating set, it is achieved wind energy is followed the trail of；

(3) use search by hill climbing method that rotary speed-torque control program is modified；

(4) the statistics unit final torque disturbance value to applying under the most corresponding rotating speed, in torque for a long time to certain party In time adjusting, rotary speed-torque table is finely adjusted by controller, reduces and finds the optimized rotating speed time.

In described step (1), specifically comprise the following steps that

A) wind speed round W during corresponding optimal wind energy capture under certain wind speed is calculated；By W, in conjunction with set gear box no-load voltage ratio, Obtain set generator rotating speed R；Computing formula such as formula (2)

$\mathrm{\λ}=\frac{R_{w}W}{V}---\left(2\right)$

Wherein, R_wFor wind wheel radius, W is wind speed round, and V is wind speed；

B) by wind energy turbine set average air density p, convolution (1), calculate the maximum machine that unit absorbs at a certain wind speed Can P_m；

C) the maximum machine energy P absorbed by unit_m, in conjunction with the efficiency eta of unit, show that unit sends maximum electric power P_e；

P_e=η * P_m (3)

D) by P_eWith generator speed R, torque T, it is thus achieved that torque T corresponding under certain wind speed, as shown in formula (4), formula Middle A is constant；

P_e=A*R*T. (4)

In described step (3), method particularly includes: on wind power generating set torque control value, increase torque disturbance value Δ ω, and the change of observed power, if power increases, then the direction of disturbance is constant, otherwise, changes perturbation direction.

In described step (3), the value of Δ ω is introduced feedback and ratio controlling unit, increases the stability controlled, subtract Few regulating time, calculates the value of Δ ω by formula (5), (6) mode:

$\left\{\begin{array}{cc}\mathrm{\Δ}P\left(K\right)=P\left(K\right)-P(K-1)& \left(5\right)\\ \mathrm{\Δ}\mathrm{\ω}(K+1)=\mathrm{\Δ}P\left(K\right)\·K_t& \left(6\right)\end{array}\right.$

Wherein K_tFor proportionality coefficient, P (K) be power of the assembling unit value after kth regulation, P (K-1) be regulate for the K-1 time after machine Organize performance number, Δ P (K) is power of the assembling unit changing value after kth regulates, Δ ω (K+1) is the K+1 time torque disturbance value；Foundation Power P-rotating speed W curve, under any wind speed, has on P value maximum point:Thus, P is set_b, as | Δ P (K) | < P_bTime, Take K_t=0, prevent over control from occurring.

The method that the invention have the benefit that is simple, practical, based on rotary speed-torque table method, in conjunction with search by hill climbing method Determine that combination of wind-driven generator fits rotating speed, it is achieved optimal wind energy captures；Meanwhile, in conjunction with long-time data statistics, to rotary speed-torque Table is finely adjusted, and shortening system determines the time of optimum speed, adds unit generation amount.

Accompanying drawing explanation

Fig. 1 is that the search by hill climbing of the present invention sends out flow chart.

Detailed description of the invention:

The invention will be further described with embodiment below in conjunction with the accompanying drawings.

The mechanical output absorbing wind energy when wind power generating set is properly functioning and produce is as follows with wind speed relation:

$P_m=\frac{1}{2}{\mathrm{\&rho;AC}}_P{V}^3---\left(I\right)$

In formula: P_mFor mechanical output, ρ is atmospheric density, and A is wind wheel sweeping area, C_PFor power coefficient, V is wind Speed.

In unit running process, in (I) formula, ρ, A are fixed value, are not affected by unit allocation, thus, it can be known that at wind speed V mono- In the case of Ding, the approach improving wind power generating set capture wind energy improves power coefficient C exactly_P.Power coefficient C_P With ratio (tip speed ratio) λ of wind generator set blade top linear velocity Yu wind speed, pitch angle beta has substantial connection；Specified Time below wind speed, pitch angle beta remains 0, can realize optimal wind energy capture by adjusting tip speed ratio λ.

Under normal circumstances, the first meeting of wind power generating set design goes out the optimal tip-speed ratio of unit by simulation calculation, at unit In actual operation, control the actual tip-speed ratio of unit and infinitely can realize optimal wind energy capture near optimal tip-speed ratio.

The method is primarily based on optimal tip-speed ratio and calculates wind power generating set rotary speed-torque table, i.e. wind power generating set wind Wheel speed and the relation curve of generator torque, calculation procedure is as follows:

A) wind speed round W during corresponding optimal wind energy capture under certain wind speed is calculated.By W, in conjunction with set gear box no-load voltage ratio (if any) set generator rotating speed R can be obtained.Computing formula such as formula (II)

$\mathrm{\&lambda;}=\frac{R_{w}W}{V}---\left(II\right)$

Wherein, R_wFor wind wheel radius, W is wind speed round, and V is wind speed.

B) by wind energy turbine set average air density p, in conjunction with formula (I), the maximum machine that unit absorbs at a certain wind speed is calculated Can P_m。

C) the maximum machine energy P absorbed by unit_m, in conjunction with the efficiency eta of unit, can show that unit sends maximum electric work Rate P_e。

D) by P_eTorque T corresponding under this wind speed can be obtained with the relation of generator speed R, torque T.

Thus, just obtain rotary speed-torque table, after rotational speed and torque table draws, be cured in wind turbine generator system controller In, unit operationally foundation wind speed round is by acquisition torque value of tabling look-up, it is achieved wind energy is followed the trail of.

Under normal circumstances, atmospheric density changes (especially bright in the Summer and winter temperature difference in units of year in the range of ρ ± Δ ρ Aobvious area), when wind energy turbine set atmospheric density changes, just need to be revised on the basis of rotary speed-torque is list-directed, To guarantee the wind power generating set capture to wind energy.

This programme uses search by hill climbing method to be modified rotary speed-torque control program, specific as follows: at wind-driven generator Increasing torque disturbance value Δ ω, and the change of observed power on group torque control value, if power increases, then the direction of disturbance is not Becoming, otherwise, change perturbation direction, algorithm flow is as shown in Figure 1.

In control, the value of Δ ω is introduced feedback and ratio controlling unit, increases the stability controlled, when reducing regulation Between, the value of Δ ω is calculated by formula (III), (IV) mode.

$\left\{\begin{array}{cc}\mathrm{\&Delta;}P\left(K\right)=P\left(K\right)-P(K-1)& \left(III\right)\\ \mathrm{\&Delta;}\mathrm{\&omega;}(K+1)=\mathrm{\&Delta;}P\left(K\right)\&CenterDot;K_t& \left(IV\right)\end{array}\right.$

Wherein K_tFor proportionality coefficient, according to P (power)-W (rotating speed) curve, under certain wind speed, P value maximum point has:Thus, P is set_b, as | Δ P (K) | < P_bTime, take K_t=0, prevent over control from occurring.

Thus, unit can ensure that and operates in optimal C_pNear Zhi, it is achieved optimal wind energy captures.

Although the detailed description of the invention of the present invention is described by the above-mentioned accompanying drawing that combines, but not the present invention is protected model The restriction enclosed, one of ordinary skill in the art should be understood that on the basis of technical scheme, and those skilled in the art are not Need to pay various amendments or deformation that creative work can make still within protection scope of the present invention.

Claims (3)

1. a wind power generating set optimal wind energy catching method, is characterized in that: comprise the following steps:

(1) relation curve of wind-driven generator group wind-wheel rotating speed and generator torque is calculated based on optimal tip-speed ratio, i.e. rotating speed-turn Square table；

(2) the controller solidification rotary speed-torque table of wind power generating set, it is achieved wind energy is followed the trail of；

(3) use search by hill climbing method that rotary speed-torque control program is modified；

(4) the statistics unit final torque disturbance value to applying under the most corresponding rotating speed, adjusts to specific direction for a long time in torque Time whole, rotary speed-torque table is finely adjusted by controller, reduces and finds the optimized rotating speed time.

In described step (3), method particularly includes: on wind power generating set torque control value, increase torque disturbance value Δ ω, and The change of observed power, if power increases, then the direction of disturbance is constant, otherwise, changes perturbation direction.

2. a kind of wind power generating set optimal wind energy catching method as claimed in claim 1, is characterized in that: described step (1) In, specifically comprise the following steps that

A) wind speed round W during corresponding optimal wind energy capture under certain wind speed is calculated；By W, in conjunction with set gear box no-load voltage ratio, it is thus achieved that Set generator rotating speed R；Computing formula such as formula (2)

$\mathrm{\&lambda;}=\frac{R_{w}W}{V}---\left(2\right)$

Wherein, R_wFor wind wheel radius, W is wind speed round, and V is wind speed；

By wind energy turbine set average air density p, the mechanical output produced in conjunction with wind power generating set absorbs wind energy time properly functioning As follows with wind speed relation:

$P_m=\frac{1}{2}{\mathrm{\&rho;AC}}_P{V}^3---\left(1\right)$

In formula: P_mFor mechanical output, ρ is atmospheric density, and A is wind wheel sweeping area, C_PFor power coefficient, V is wind speed, meter Calculate the maximum machine energy P that unit absorbs at a certain wind speed_m；

B) the maximum machine energy P absorbed by unit_m, in conjunction with the efficiency eta of unit, show that unit sends maximum electric power P_e；

P_e=η * P_m (3)

C) by P_eWith generator speed R, torque T, it is thus achieved that torque T corresponding under certain wind speed, as shown in formula (4), in formula, A is Constant；

P_e=A*R*T. (4)

3. a kind of wind power generating set optimal wind energy catching method as claimed in claim 1, is characterized in that: described step (3) In, the value of Δ ω is introduced feedback and ratio controlling unit, increases the stability controlled, reduce regulating time, pass through formula (5), (6) mode calculates the value of Δ ω:

$\left\{\begin{array}{cc}\mathrm{\&Delta;}P\left(K\right)=P\left(K\right)-P(K-1)& \left(5\right)\\ \mathrm{\&Delta;}\mathrm{\&omega;}(K+1)=\mathrm{\&Delta;}P\left(K\right)\&CenterDot;K_t& \left(6\right)\end{array}\right.$

Wherein K_tFor proportionality coefficient, P (K) be power of the assembling unit value after kth regulation, P (K-1) be regulate for the K-1 time after the power of the assembling unit Value, Δ P (K) are that power of the assembling unit changing value, Δ ω (K+1) are the K+1 time torque disturbance value after kth regulation；Foundation power P- Rotating speed W curve, under any wind speed, has on P value maximum point:Thus, P is set_b, as | Δ P (K) | < P_bTime, take K_t= 0, prevent over control from occurring.