CN202768249U - Wind generation set control system based on pneumatic torque calculation model - Google Patents

Abstract

The utility model provides a wind generation set control system based on pneumatic torque calculation model. The wind generation set control system based on the pneumatic torque calculation model comprises a laser radar tachymeter, a Programmable Logic Controller (PLC) and a wind generation set. The laser radar tachymeter is arranged on a hub and is used for measuring airflow velocities of a range on an impeller in front of the laser radar tachymeter, wherein the range is located away from the laser radar tachymeter by two to three times of the diameter of the impeller. The PLC controller comprises a torque controller, a pitch-control controller, a pneumatic torque calculation module and a controller given value correction module inside. The wind generation set is controlled by the PLC controller to output, and generators of the wind generation set and the impeller of the wind generation set are controlled by revised torque given value and revised pitch angle given value. The wind generation set control system based on the pneumatic torque calculation model ensures that the wind generation set control system based on the pneumatic torque calculation module can response to changes of wind velocities in advance and revise effects of the pitch-control and the torque control, improves utilization of wind energy of the wind generation set and helps to solve whole machine fatigue loading and loss of generating capacity which are caused by inertia of the impeller and a pitch-control system.

Description

A kind of control system of wind turbines based on pneumatic torque calculation model

Technical field

The utility model relates to technical field of wind power generation, particularly relates to a kind of control system of wind turbines based on pneumatic torque calculation model.

Background technique

In recent years, along with the continuous progress of wind-power electricity generation relevant control technology, the speed-changing oar-changing wind power generating set becomes at present main installation type with its efficient wind energy utilization and the larger advantages such as single-machine capacity.

Speed-changing oar-changing wind-powered electricity generation unit is when low wind speed (below the rated wind speed), master control system is adjusted to optimum (or minimum) with the propeller pitch angle of blade, adjust wheel speed by control generator electromagnetic torque, blower fan is operated under the optimum tip speed ratio state, to realize maximal wind-energy capture; After wheel speed arrived rated speed, rotating speed can not increase along with the increase of wind speed, need to wheel speed be remained near the rated speed by increasing the generator electromagnetic torque, made the wind-powered electricity generation unit enter permanent rotary speed area.When wind speed increased to rated wind speed, it is specified that torque reaches, and generator reaches rated power simultaneously, and at this moment, master control system can increase the wind energy that propeller pitch angle is caught with minimizing if wind speed continues to increase, and guarantees the generator set nonoverload, enters the output-constant operation stage.

In wind-powered electricity generation unit actual moving process, because the existence of turbulent flow and fitful wind is engraved in fluctuation during wind speed, guarantee that running of wind generating set is at the operation point of design, control generator torque and propeller pitch angle that need to be correct according to current wind speed.Because the rotary inertia of impeller is larger, the variation of wind speed is reflected to wheel speed, is used for regulating torque and propeller pitch angle often lags behind the long period again.When especially below rated wind speed, moving, in order to follow the tracks of optimum tip speed ratio, need to constantly regulate wheel speed according to wind speed, but torque that should the stage in the existing master control system is the product according to the optimum gain coefficient of vane airfoil profile property calculation and generator speed square to be obtained, be equivalent to a kind of open loop control mode, the torque value that is obtained by the method is difficult to accurately follow the tracks of optimum tip speed ratio, causes wind energy utilization on the low side.When rated wind speed is above, also can cause because of the hysteresis of rotation speed change and pitch-controlled system the wind speed at propeller pitch angle and current impeller place not mate according to wheel speed control propeller pitch angle, so that larger load is born at impeller and tower cylinder place.Therefore, if the wind speed that can measure impeller the place ahead also calculates the aerodynamic torque at impeller place in advance, in order to revise the output of torque and change oar controller, the fatigue load of wind-powered electricity generation unit has become one of important research target of current related domain in the time of can guaranteeing to have higher wind energy utilization can reduce high wind speed again below the rated wind speed.

The model utility content

The purpose of this utility model is by a kind of control system of wind turbines based on pneumatic torque calculation model, and the torque setting value when it can make the following operation of rated wind speed on the one hand is more reasonable, accurately follows the tracks of optimum tip-speed ratio, improves wind energy utilization; On the other hand, operation the time can shift to an earlier date the size of rationally regulating propeller pitch angle more than rated wind speed, effectively reduces the fitful wind at impeller place or impeller that the pitch-controlled system delay causes and the loss of pylon fatigue load and generated energy.

For solving the problems of the technologies described above, a kind of control system of wind turbines based on pneumatic torque calculation model of the utility model comprises: be installed on the wheel hub, be used for measuring the tachometer of the place ahead impeller diameter 2-3 times distance airspeed; Be built-in with the PLC controller of torque controller, change oar controller, pneumatic torque calculation module and controller setting value correcting module; And according to the torque setting value through revising of PLC controller output and the wind-powered electricity generation unit of propeller pitch angle setting value control generator and impeller.

As further improvement, described tachometer is the lidar air speed measuring apparatus.

Compared with prior art, the utlity model has following beneficial effect:

1, introduces comparatively ripe laser windfinding radar and come the wind speed of flow path direction to measure to impeller the place ahead, make the variation that can respond in advance wind speed based on the control system of wind turbines of pneumatic torque calculation model;

2, set up the aerodynamic torque computation model of impeller according to parameters such as the aerofoil profile parameter of wind-powered electricity generation unit, optimum tip speed ratio and optimum power coefficients, accurately calculate the aerodynamic torque that this section air-flow can produce with running statees such as the wheel speed of the speed of impeller the place ahead air-flow and current blower fan, propeller pitch angles, revise the effect that becomes oar and torque control, improve the wind energy utilization of wind-powered electricity generation unit;

3, can adjust in advance the output of variable blade control system according to the wind speed in impeller the place ahead, help to solve because complete machine fatigue load and generated energy that impeller inertia and pitch-controlled system postpone to cause lose.

Description of drawings

Above-mentioned only is the general introduction of technical solutions of the utility model, and for can clearer understanding technological means of the present utility model, the utility model is described in further detail below in conjunction with accompanying drawing and embodiment.

Fig. 1 is that the utility model is with the composition schematic diagram of the control system of wind turbines of the gentle dynamic torque computing module of lidar anemoscope.

Embodiment

Below in conjunction with accompanying drawing embodiment of the present utility model is further specified:

See also shown in Figure 1ly, a kind of control system of wind turbines based on pneumatic torque calculation model of the utility model comprises lidar air speed measuring apparatus, PLC controller and wind-powered electricity generation unit.

Wherein, the lidar air speed measuring apparatus is installed on the wheel hub, is used for measuring the place ahead impeller diameter 2-3 times distance airspeed.

The wind-powered electricity generation unit mainly comprises generator, current transformer, pitch-controlled system and impeller, according to the torque setting value through revising and propeller pitch angle setting value control generator and the impeller of PLC controller output.

The PLC controller, namely the utility model is based on the wind turbine group controller of pneumatic torque calculation model, and it is built-in with torque controller, becomes oar controller, pneumatic torque calculation module and controller setting value correcting module.According to the wind-powered electricity generation unit controlling method of the utility model based on pneumatic torque calculation model, the workflow of above-mentioned module may further comprise the steps.

Step 1 by lidar air speed measuring apparatus, generator and impeller, is obtained respectively the airspeed V of wheel hub the place ahead impeller diameter 2-3 times distance _Wind, the propeller pitch angle β of impeller current time, and generator rotational angular velocity ω _M, calculate the pneumatic torque at impeller place, and calculate corresponding electromagnetic torque.

At present, in the wind-powered electricity generation unit design process, the aerodynamic characteristic of impeller is mainly analyzed according to the foline theory, for consistent with design performance, adopts the output of calculating and revise torque controller based on the pneumatic torque model of foline theory.

Theoretical and the actuator dial concept according to the foline in the aerodynamics, the pneumatic torque that the impeller place produces is:

$Q_A=\frac{1}{2}\mathrm{\ρ}{\mathrm{ARU}}^2\frac{C_P(\mathrm{\λ},\mathrm{\β})}{\mathrm{\λ}}$

Wherein: ρ is air density;

A is the impeller wind sweeping area, is A=π R ²

R is impeller radius;

U is the wind speed at impeller place;

C _p(λ, β) is power coefficient, and λ is tip speed ratio, and β is propeller pitch angle.

Because the complexity of air-flow around the blade is directly not too reliable with change oar controller and torque control that wind speed participates in the master controller, usually according to tip speed ratio, uses:

Wind speed during replacement is calculated, thereby:

$Q_A=\frac{1}{2}\mathrm{\ρ}{\mathrm{\πR}}^5\frac{C_P(\mathrm{\λ},\mathrm{\β})}{{\mathrm{\λ}}^3}{\mathrm{\ω}}_B^2$

ω wherein _BBe wheel rotation angular velocity, unit is rad/s.

Because in the actual motion, the measuring accuracy of wheel speed is not high, and normally controls the generator electromagnetic torque and control the running of wind generating set state, in conjunction with the characteristic of wind-powered electricity generation unit transmission system, can convert out wheel speed with generator speed, and then calculate corresponding generator electromagnetic torque and be:

$Q_M=\frac{\mathrm{\π\ρ}{R}^5{C}_p(\mathrm{\λ},\mathrm{\β})}{2{\mathrm{\λ}}^3{G}^3}{\mathrm{\ω}}_M^2$

Wherein: ω _MBe the generator rotational angular velocity;

G is the uni-drive gear box velocity ratio.

In wind-powered electricity generation unit design process, its acceptable operating point is often definite all definite and corresponding with wind speed later in generator capacity and vane airfoil profile data, therefore can set up wind speed and optimum tip speed ratio λ, propeller pitch angle β and power coefficient C _PMapping table, λ and β in the time of namely just accessing it and arrive impeller place by the airspeed of measuring impeller the place ahead, and then can calculate the torque Q of correspondence _M

Step 2 is obtained the torque setting value T of current torque controller output _Dem

Step 3 is obtained the propeller pitch angle setting value P of current change oar controller output _Dem

Step 4 by controller setting value correcting module, is revised torque controller or is become the setting value that oar control is exported.

Specifically, if the generated output of current fan operation is below rated power:

(1) works as Q _MLess than the specified of generator or peak torque Q _EThe time, then according to calculated value Q _MWith current torque controller output T _DemPoor Δ T=Q _M-T _Dem, in conjunction with the time t of air-flow arrival impeller _WAnd controller output cycle t _Step, adjusting the generator torque setting value is T ' _Dem=T _Dem+ (Δ T/t _W) * t _StepWork as Q _MWith Q _EWhen equating, stop to revise.

(2) work as Q _MGreater than the specified of generator or peak torque Q _EThe time, show that then wind speed is increasing, the wind-powered electricity generation unit be about to from below the rated power to the above transition of rated power, the measuring wind V that should table look-up and ask _WindCorresponding design propeller pitch angle value P _Des, calculate and current optimum propeller pitch angle P _OptDifference DELTA P'=P _Des-P _Opt, in conjunction with the time t of air-flow arrival impeller _WAnd controller output cycle t _Step, adjust the propeller pitch angle setting value

P' _dem=P _min+(ΔP'/t _W)×t _step

Wherein, P _MinBe minimum propeller pitch angle.

Until the pneumatic torque of impeller of calculating is identical with nominal torque or become the output that the output of oar controller stops to revise change oar controller when identical with revised propeller pitch angle setting value.

If the generated output of current running of wind generating set is when rated power is above:

(3) work as Q _MDuring greater than the current torque value of generator, show that then the wind speed in impeller the place ahead increases, need to continue to increase propeller pitch angle and reduce catching of impeller place wind energy, the measuring wind V that should table look-up and ask _WindPropeller pitch angle value P during corresponding design _DesWith current P _DemDifference DELTA P=P _Des-P _Dem, in conjunction with the time t of air-flow arrival impeller _WAnd controller output cycle t _StepAdjust propeller pitch angle setting value P' _Dem=P _Dem+ (Δ P/t _W) * t _StepUntil the pneumatic torque of impeller of calculating is identical with nominal torque or become the output that the output of oar controller stops to revise change oar controller when identical with revised propeller pitch angle setting value, so that pitch-controlled system can respond the increase of wind speed in advance, reduce fatigue load.

(4) as QM during less than the current torque value of generator, show that then the wind speed in impeller the place ahead reduces, need to reduce propeller pitch angle and increase catching of impeller place wind energy, the measuring wind V that should table look-up and ask _WindPropeller pitch angle value P during corresponding design _DesWith current P _DemDifference DELTA P=P _Des-P _Dem, in conjunction with the time t of air-flow arrival impeller _WAnd controller output cycle t _StepAdjust propeller pitch angle setting value P' _Dem=P _Dem+ (Δ P/t _W) * t _StepUntil the pneumatic torque of impeller of calculating is identical with nominal torque or to become the output of oar controller identical with revised propeller pitch angle setting value or stop to revise the output of change oar controller when reaching minimum propeller pitch angle, so that pitch-controlled system can respond reducing of wind speed in advance, avoid the loss of generated energy.

The utility model provides a kind of control system of wind turbines based on pneumatic torque calculation model, its wheel hub in wind power generating set installs the lidar air speed measuring apparatus additional, to wheel hub the place ahead approximately the wind speed of impeller diameter 2-3 times of distance measure, as the input of aerodynamic torque computing module; The aerodynamic torque computing module calculates the following aerodynamic torque that constantly can produce of impeller by the wind speed of measurement and rotating speed and the propeller pitch angle of current impeller; Controller setting value correcting module, comprise the correction of generator torque setting value and the correction of propeller pitch angle setting value, calculate time and the corresponding impeller air power torque that this part air-flow arrives impeller according to the air speed value of measuring, compare to revise generator torque and become the oar setting value with the output of current torque controller, so that blower fan can respond the variation of wind speed in advance, when rated wind speed is following, can follow the tracks of preferably optimum tip-speed ratio on the one hand, improve wind energy utilization; When moving more than rated wind speed on the other hand, the output that concerns adjustment change oar controller according to calculating torque and generator specified (or maximum) torque responds in advance the variation of wind speed, thereby effectively reduces the loss of fatigue load or generated energy.

The above; it only is preferred embodiment of the present utility model; be not that the utility model is done any pro forma restriction, those skilled in the art utilize the technology contents of above-mentioned announcement to make a little simple modification, equivalent variations or modification, all drop in the protection domain of the present utility model.

Claims (2)

1. control system of wind turbines based on pneumatic torque calculation model is characterized in that comprising:

Be installed on the wheel hub, be used for measuring the tachometer of the place ahead impeller diameter 2-3 times distance airspeed;

Be built-in with the PLC controller of torque controller, change oar controller, pneumatic torque calculation module and controller setting value correcting module; And

According to the torque setting value through revising of PLC controller output and the wind-powered electricity generation unit of propeller pitch angle setting value control generator and impeller.

2. a kind of control system of wind turbines based on pneumatic torque calculation model according to claim 1 is characterized in that described tachometer is the lidar air speed measuring apparatus.

Images