CN-115809395-B - Method and device for correcting optimal moment coefficient of wind driven generator

CN115809395BCN 115809395 BCN115809395 BCN 115809395BCN-115809395-B

Abstract

The invention belongs to the technical field of wind power generation, and particularly relates to a method and a device for correcting an optimal moment coefficient of a wind power generator. The method comprises the steps of firstly, obtaining a plurality of data pairs when the wind driven generator exits from a maximum power tracking state, wherein one data pair comprises wind energy utilization rate and a blade tip speed ratio corresponding to the wind energy utilization rate, then, screening out the data pairs with the wind energy utilization rate larger than that in a balance state from the obtained data pairs, calculating to obtain a standard blade tip speed ratio according to all the blade tip speed ratios in the screened data pairs, and finally, correcting an optimal torque coefficient by utilizing the difference between the standard blade tip speed ratio and the blade tip speed ratio in the balance state, so that the error of the optimal torque coefficient is gradually reduced, and the optimal torque coefficient can be corrected along with the slow change of the parameters of the wind driven generator, and the optimal torque coefficient can be kept at an optimal value for a long time by virtue of self-correction adjustment, so that the power generation performance of the wind driven generator is improved.

Inventors

WANG CHAODONG
XU FENGYOU
LI YANQING
LIU WEIPENG
LU XIAOGUANG
LI SHUHUI
CHENG ZHANWEI

Assignees

许昌许继风电科技有限公司

Dates

Publication Date: 20260508
Application Date: 20221129

Claims (7)

1. The method for correcting the optimal moment coefficient of the wind driven generator is characterized by comprising the following steps of: 1) When the wind driven generator exits from the maximum power tracking state, a plurality of data pairs are acquired when the wind driven generator is in the maximum power tracking state, wherein one data pair comprises a wind energy utilization rate and a tip speed ratio corresponding to the wind energy utilization rate; 2) Screening out a data pair with wind energy utilization rate greater than that in a balance state from the acquired data pairs, and calculating the average value of all tip speed ratios in the screened data pairs to obtain a standard tip speed ratio, wherein the balance state refers to a state when the fluctuation amplitude of the tip speed ratio is smaller than a set threshold value; 3) And calculating to obtain the corrected optimal moment coefficient by using the following formula: , Indicating the optimal moment coefficient after correction, Indicating the optimal moment coefficient before correction, Representing a standard tip speed ratio, Indicating the tip speed ratio at equilibrium, Is a correction factor and 。
2. The method for correcting an optimal moment coefficient of a wind turbine according to claim 1, wherein, Obtained by field debugging test.
3. The method for correcting an optimal moment coefficient of a wind power generator according to claim 1, wherein a calculation formula of a wind energy utilization rate is: in the formula, Representing wind energy utilization rate; 、、、、 respectively representing the electric energy output quantity of the generator, the mechanical energy increment of the wind wheel, the air density of the wind power plant, the wind sweeping area of the wind wheel, the wind speed value or the corrected wind speed value in the sampling period; 、、 Respectively representing the rotational inertia of the wind wheel, the rotational speed of the wind wheel at the moment T and the rotational speed of the wind wheel at the moment t+T, wherein T represents the sampling period.
4. The method for correcting an optimal moment coefficient of a wind turbine according to claim 1, wherein the tip speed ratio is calculated by the formula: in the formula, Indicating the tip speed ratio, The rotating speed of the wind wheel is represented, Representing the wind speed value or the corrected wind speed value, Indicating the radius of the rotor.
5. The method for correcting optimal moment coefficients of a wind driven generator according to claim 1, further comprising calculating a generator moment command by using the generator rotation speed and the corrected optimal moment coefficients, and controlling the wind driven generator by using the generator moment command.
6. The method for correcting an optimal moment coefficient of a wind turbine according to claim 1, wherein the initial value of the optimal moment coefficient is set according to a wind turbine parameter and an environmental parameter.
7. An optimum moment coefficient correction device for a wind turbine, comprising a memory and a processor for executing computer program instructions stored in the memory to implement the optimum moment coefficient correction method for a wind turbine according to any one of claims 1 to 6.

Description

Method and device for correcting optimal moment coefficient of wind driven generator Technical Field The invention belongs to the technical field of wind power generation, and particularly relates to a method and a device for correcting an optimal moment coefficient of a wind power generator. Background In order to improve the power generation efficiency of the wind generating set, the wind generating set adopts maximum power tracking control for most of the time, the most main control parameter of the control algorithm is the optimal moment coefficient, and the accuracy of the control algorithm directly influences the control effect of the wind generating set so as to influence the power generation efficiency of the wind generating set. The parameter is calculated according to the wind power generator parameter, the wind wheel aerodynamic parameter, the transmission chain parameter and the environment variable, a control block diagram of the wind power generator is shown in fig. 1, the moment command of the wind power generator is calculated by the rotation speed of the wind power generator and the optimal moment coefficient, and the optimal moment coefficient is a preset constant parameter Kopt. The field operation data indicate that the aerodynamic parameters provided by the wind turbine manufacturer have deviation, so that the optimal moment coefficient Kopt needs field correction, and in addition, after the wind turbine generator set operates for a certain time, the aerodynamic parameters of the wind turbine also change, so that the optimal moment coefficient needs to be corrected again. The technical scheme commonly used at present is that the optimal moment coefficient is set to be a fixed value which is not modified any more, but the parameters of the wind driven generator have errors, the parameters of the wind driven generator and the environment variables can be changed along with time, the fixed value Kopt obviously influences the power generation capacity of the wind driven generator, and the wind driven generator set cannot be ensured to be in an optimal working state. Disclosure of Invention The invention aims to provide a correction method and device for an optimal moment coefficient of a wind driven generator, which are used for solving the problem that the generated energy of the wind driven generator is influenced due to the fact that the optimal moment coefficient is set to a fixed value in the prior art. In order to solve the technical problems, the invention provides a correction method for an optimal moment coefficient of a wind driven generator, which comprises the following steps: 1) When the wind driven generator exits from the maximum power tracking state, a plurality of data pairs are acquired when the wind driven generator is in the maximum power tracking state, wherein one data pair comprises a wind energy utilization rate and a tip speed ratio corresponding to the wind energy utilization rate; 2) Screening out a data pair with wind energy utilization rate greater than that in a balance state from the acquired data pairs, and calculating to obtain a standard tip speed ratio according to all tip speed ratios in the screened data pairs, wherein the balance state refers to a state when the fluctuation amplitude of the tip speed ratio is smaller than a set threshold value; 3) And calculating to obtain the corrected optimal moment coefficient by using the following formula: kopt' denotes an optimal moment coefficient after correction, kopt denotes an optimal moment coefficient before correction, Represents a standard tip speed ratio, λ0 represents a tip speed ratio at equilibrium, k is a correction factor and k >0. The method has the advantages that the method screens out the data pairs with the wind energy utilization rate greater than that in the balance state from the running data of the wind driven generator in the maximum power tracking state, further calculates the standard tip speed ratio by utilizing all tip speed ratios in the screened data pairs, and finally corrects the optimal moment coefficient by utilizing the difference between the standard tip speed ratio and the tip speed ratio in the balance state, so that the error of the optimal moment coefficient is gradually reduced, the optimal moment coefficient can be corrected along with the slow change of the environmental and wind driven generator parameters, the optimal moment coefficient can be kept at the optimal value for a long time by virtue of self-correction adjustment, and the power generation performance of the wind driven generator is improved. Further, in step 2), the standard tip speed ratio is the average value of all tip speed ratios in the screened data pair. Further, the calculation formula of the wind energy utilization rate is as follows: Wherein, C p represents wind energy utilization rate, w e、wm, ρ and S, v respectively represent generator electric energy output quantity, wind wheel mechanical energ