CN202545109U - Wind generating set optimal control system - Google Patents

Abstract

The utility model discloses a wind generating set optimal control system. The system comprises a wind generating set signal processing subsystem, an optimal control signal executing subsystem and a system state updating subsystem which are sequentially connected. By adopting the technical scheme provided in the utility model and replacing a conventional PID controller, the system which directly outputs an optimal control signal to wind generators achieves system stability and the tracking of a target reference curve by system outputs. The wind generating set optimal control system plays an important role in enhancing the control performances of a wind generating set control system.

Description

A kind of wind power generating set optimal control system

Technical field

The utility model relates to technical field of wind power generation, relates in particular to a kind of wind power generating set optimal control system.

Background technique

Wind power generator control system is the core of whole wind power generating set, directly affects performance, efficient and the quality of power supply of whole wind force generating system.Wind power generating set can receive the influence of links such as uncertainty and the load disturbance of wind speed in running; For the control system of wind power generating set; Controller reaches satisfied control effect; Need reach the stability requirement of control system, and can make system reach desirable electric power output by the tracking target reference curve.

The control system of wind power generating set mainly comprises moment controlling system and pitch control system at present; These two systems mainly use the PID controller; It through systematic observation to data and a predefined reference value compare; Calculate new input value to the difference that draws after relatively with control algorithm then, this new input value can let the output of system reach desired value.

The PID controller:

Application percentage K _P, integration K _IWith differential K _DThree kinds of control laws are adjusted the control effect that input value obtains expecting according to the difference of system mode and reference value state.

For the PID controller in the wind turbine control system, the project planner need carry out adjusted design to its controller parameter.The magnification ratio link can make system acting rapid, and reaction velocity is fast, and steady-state error diminishes, but ratio crosses the number of oscillation that conference makes system and can increase, and the adjusting time is elongated, even becomes unstable.Integral element can be eliminated the steady-state error of system, improves the no margin of system, but can make the reaction velocity of system slack-off.Differentiation element can improve system dynamic characteristic, the variation tendency of reflection deviation signal, and can before deviation signal becomes too greatly, in system, introduce an effectively early stage corrected signal, thus accelerate the movement speed of system, minimizing adjusting time.

Regulate these parameters and need take all factors into consideration the dynamic and static demand of system, carry out adjusting progressively.The pid parameter regulating method generally has two big types: the one, and the theoretical calculation method of adjusting, it mainly is the mathematical model according to system, confirms controller parameter according to logarithm frequency characteristic or root locus characteristic.The 2nd, the engineering setting method, it mainly relies on engineering experience, directly in the test of control system, carries out.These PID controller parameter regulating methods all need be adjusted in practical engineering application and revised all the time repeatedly; Workload is big; Consuming time long, and accurately not direct numerical value corresponding relation between parameter and the figure, mostly need rely on the project planner to regulate with the experience of oneself; Exist certain sum of errors uncertain, make troubles and difficulty for the Control System Design of wind power generating set.

The model utility content

The purpose of the utility model is to propose a kind of wind power generating set optimal control system; Directly fan is imported the optimal control signal; The stability of realization system and system's output improve the control performance of wind power generator control system to the tracking of target reference curve.

For reaching this purpose, the utility model adopts following technological scheme:

A kind of wind power generating set optimal control system; Comprise wind power generating set signal processing subsystem, optimal control signal executive subsystem and system mode renewal subtense angle; Wind power generating set signal processing subsystem, optimal control signal executive subsystem and system mode are upgraded subtense angle and are connected successively; Wherein

The wind power generating set signal processing subsystem further comprises wind-driven generator signal measurement sensor and linearized model processor,

Optimal control signal executive subsystem further comprises optimal control input calculator, current transformer and change oar motor,

System mode is upgraded subtense angle and is further comprised the state renovator,

Wind-driven generator signal measurement sensor output terminal is connected with the input end of linearized model processor; The output terminal of linearized model processor is connected with the input end of optimal control input calculator, and the output terminal of optimal control input calculator is connected with the state renovator with current transformer, change oar motor respectively.

Adopted the technological scheme of the utility model; Substituted the PID controller; Directly fan output optimal control signal has realized that the stability of system and system export the tracking to the target reference curve, and is significant to the control performance that improves wind power generator control system.

Description of drawings

Fig. 1 is the structural representation of wind power generating set optimal control system in the utility model embodiment.

Fig. 2 is an optimal control input calculator schematic diagram in the utility model embodiment.

Embodiment

Further specify the technological scheme of the utility model below in conjunction with accompanying drawing and through embodiment.

Fig. 1 is the structural representation of wind power generating set optimal control system in the utility model embodiment.As shown in Figure 1, this wind power generating set optimal control system comprises wind power generating set signal processing subsystem 1, optimal control signal executive subsystem 2 and system mode renewal subtense angle 3.

Wind power generating set signal processing subsystem, optimal control signal executive subsystem and system mode are upgraded subtense angle and are connected successively.

Wherein, The wind power generating set signal processing subsystem further comprises wind-driven generator signal measurement sensor 101 and linearized model processor 102; Optimal control signal executive subsystem further comprises optimal control input calculator 201, current transformer 202 and becomes oar motor 203 that system mode is upgraded subtense angle and further comprised state renovator 301.

Wind-driven generator signal measurement sensor output terminal is connected with the input end of linearized model processor; The output terminal of linearized model processor is connected with the input end of optimal control input calculator, and the output terminal of optimal control input calculator is connected with the state renovator with current transformer, change oar motor respectively.

In the utility model embodiment, the wind power generating set signal processing subsystem is that wind-driven generator signal measurement sensor at first is installed on generator in the wind, and the rotating speed and the propeller pitch angle signal of wind-driven generator are measured and record.The signal of measuring is passing to the linearized model processor; Through built-in simulation calculation software; Wind power generating set according to concrete is provided with systematic parameter, carries out linearization to the wind-driven generator group model, obtains the linearized model of the wind power generating set in the wind speed range.The structure of wind power generating set each several part and dynamic characteristic are complicated; Comprise the wind energy characteristic; Aerodynamic characteristics of rotor, Transmitted chains system performance, generator property etc.; Whole wind power generating set is the nonlinear system of a high-order, and the design of directly this nonlinear system being carried out controller is difficulty relatively.Through wind-driven generator signal measurement sensor and linearized model processor, can set up linearized model, and then draw the optimal control input signal.

Optimal control signal executive subsystem is to be according to optimal control theory through optimal control input calculator at first; For the wind power generating set linear system of representing with state space form

y=Cx+Du, the performance index function of controller can be expressed as the linear quadratic type function of system mode and control input.The optimal solution of this linear quadratic function can be expressed as minimizing the analytical expression of performance index function; Realize the standardization of solution procedure; And can calculate optimal control parameter K and optimal control input u=Kx; Then optimum input signal is passed to current transformer and carry out torque control or pass to becoming the oar motor and carrying out the control of pitch, constitute closed loop control system, can take into account the stability of a system and the multinomial performance indexs such as quick tracking of target reference curve; And main mathematical software all is that the experiment and the emulation of this controller provides platform, for the parameter optimization design that realizes controller provides convenience.

It is at first at current time that system mode is upgraded subtense angle, will pass to system according to the optimal control input signal that original state calculates.Arrived next constantly; Next state is constantly upgraded as original state through embedded software with the system mode renovator; And then calculate next optimal control input constantly and pass to system, analogize with this backward, formed a feedback of status closed-loop system.

In the wind power generating set signal processing subsystem; Motor speed and propeller pitch angle signal by wind-driven generator signal measurement sensor measurement wind-driven generator; Be provided with by the concrete parameter of linearized model processor then according to wind power generating set; Carry out linearization in the wind speed range during simultaneously according to moment controlling system and pitch control system work, obtain the linear system state-space model under each wind speed:

$\stackrel{\·}{x}=\mathrm{Ax}+\mathrm{Bu},$ y=Cx+Du

The input quantity u of these state-space models is a wind speed, propeller pitch angle controlled quentity controlled variable and generator torque controlled quentity controlled variable, and output quantity y is generator speed and propeller pitch angle, and x is the system mode of wind-powered electricity generation unit, and A, B, C and D are the system mode matrix.

In the optimal control signal executive subsystem, by the state-space model of optimal control input calculator to the linear system set up, definition Quadratic Function Optimization

$J={\∫}_0^{\∞}(y^{T}y+u^T\mathrm{Ru})$

As performance index function, purpose is to calculate the optimal control input through this performance index function, reduces system's output error, to reach systematic error and the optimum purpose of control energy synthesis.First y among the performance index function J ^TY is illustrated in the system work process requirement and the restriction of the output vector y of system, is used for retraining the error in the control procedure, guarantees the rapidity of control system response and the accuracy of terminal output state.Second u among the performance index function J ^TRu representes in the system dynamic course constraint and the requirement to the controlled quentity controlled variable input, wherein y ^TAnd u ^TIn T represent y and u are got transpose of a matrix; U is optimal control input, and matrix R requires the positive definite matrix set, its numerical value to be used to reflect that the input that reference target is adjusted in output requires and the input of required controlled quentity controlled variable is big or small according to the control input; This can be used for limiting amplitude and the flatness of u; Guaranteeing system safety operation, and the energy consumption of restriction control procedure is also played an important role, thus the efficiency property of the system of assurance.The target of optimal control input design is to calculate an optimal control input u; Make performance index function J reach minimum; Thereby output y and controlled quentity controlled variable u are retrained and limit, obtain the optimal control input, reach the stable convergence of realization control system and the requirement of tracking target reference curve.This optimal control input can be expressed as and minimize performance index function:

$\underset{u}{\min }J={\∫}_0^{\∞}(y^{T}y+u^T\mathrm{Ru}).$

When system when being controlled, because the included time range of performance index function is constantly to begin to infinity from zero, according to the graceful optimal theoretical of Bel, this optimal control input exists and is unique, and optimal control is input as:

u=Kx。

The optimal control parameter K of this moment can pass through formula

K=-(B ^TSB+R) ^-1B ^TSA

Calculate, S wherein is a Riccati equation:

A ^TSA-S-A ^TSB(B ^TSB+R) ^-1B ^TSA+C ^TC=0

Unique positive definite symmetric solution.This optimal control input u has comprised the optimal control input of current time and in the estimation of current time to the input of optimal control constantly in future.

Then this optimal control input signal is passed to current transformer and carry out torque control or pass to change oar motor carrying out the control of pitch, realize the control effect, as shown in Figure 2.

System mode is upgraded in the subtense angle, in practical application, according at the original state x of current time and the controller parameter value K that calculates, draws the optimal control input of current time.Arrived next constantly, upgraded next original state constantly, and then calculated next optimal control input constantly, analogized backward, formed a feedback of status closed-loop system with this with the system mode renovator.Adopting the closed-loop system of this optimal control input is stable convergence, and dynamic response is rapid, and system's output can accurately reach the reference target value.

The PID controller of using in the wind power generating set at present

Need be to three parameter K _P, K _I, K _DCarry out adjusting one by one repeatedly; And the direct fan output optimal control signal of the optimal controller that the utility model embodiment is designed; Carry out the control of torque or pitch; And can satisfy control system stability and, guarantee the control effect of wind turbine control system under each wind speed the accurate tracking of aim curve.

The above; Be merely the preferable embodiment of the utility model; But the protection domain of the utility model is not limited thereto; Anyly be familiar with this technological people in the technical scope that the utility model disclosed, the variation that can expect easily or replacement all should be encompassed within the protection domain of the utility model.Therefore, the protection domain of the utility model should be as the criterion with the protection domain of claim.

Claims (1)

1. wind power generating set optimal control system; It is characterized in that; Comprise wind power generating set signal processing subsystem, optimal control signal executive subsystem and system mode renewal subtense angle; Wind power generating set signal processing subsystem, optimal control signal executive subsystem and system mode are upgraded subtense angle and are connected successively, wherein

The wind power generating set signal processing subsystem further comprises wind-driven generator signal measurement sensor and linearized model processor,

Optimal control signal executive subsystem further comprises optimal control input calculator, current transformer and change oar motor,

System mode is upgraded subtense angle and is further comprised the state renovator,

Wind-driven generator signal measurement sensor output terminal is connected with the input end of linearized model processor; The output terminal of linearized model processor is connected with the input end of optimal control input calculator, and the output terminal of optimal control input calculator is connected with the state renovator with current transformer, change oar motor respectively.

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