CN-115640668-B - Photovoltaic power station theoretical generation power calculation method and device based on template inverter

CN115640668BCN 115640668 BCN115640668 BCN 115640668BCN-115640668-B

Abstract

The invention provides a calculation method and a calculation device of theoretical generated power of a photovoltaic power station based on a template inverter, wherein the method comprises the steps of dividing the total-station inverter of the photovoltaic power station according to the model in advance, and determining the template inverters of the inverters with different models; the method comprises the steps of establishing a linear regression model of the theoretical power of the photovoltaic power station along with the change of the output of a template inverter, obtaining a coefficient matrix of the regression model according to a least square method, solving correlation coefficients in the coefficient matrix according to the historical output of the photovoltaic power station and the historical output of the template inverter, obtaining a regression model with known correlation coefficients, and obtaining the theoretical power of the current photovoltaic power station according to the linear regression model with known correlation coefficients of the output of the current template inverter. The calculation accuracy of the theoretical generated power of the photovoltaic power station is improved, the accuracy of the calculation result of the photovoltaic power discarding amount in the photovoltaic power station discarding limit is ensured, accurate operation data is provided for power grid dispatching and photovoltaic development planning, and the safe and stable operation problem of the power grid is ensured.

Inventors

CAO MAN
YIN ZHIYONG
LIU JINNING
WANG YONG
AN SHU
GUO XIN
LI LANKAI

Assignees

中国人民解放军陆军工程大学

Dates

Publication Date: 20260505
Application Date: 20220817

Claims (5)

1. A calculation method of theoretical generated power of a photovoltaic power station based on a template inverter is characterized by comprising the following steps: Dividing total-station inverters of a photovoltaic power station according to models in advance, and determining template inverters of different models; based on a linear regression model of the theoretical power generation of the photovoltaic power station, which is established in advance and changes along with the output of the template inverter, acquiring a coefficient matrix of the regression model according to a least square method; according to the historical output of the photovoltaic power station and the historical output of the template inverter which are obtained in advance, solving the correlation coefficient in the coefficient matrix, and obtaining a regression model with known correlation coefficient; obtaining theoretical power generation of the current photovoltaic power station according to the current template inverter output through a linear regression model with known correlation coefficient; the linear regression model based on the change of the theoretical power generation power of the photovoltaic power station along with the output change of the template inverter specifically comprises the following steps: Obtaining a linear regression model according to equation 1: equation 1; Wherein P j is the theoretical generated power of the photovoltaic power station j, K is the model number of the inverter, K is the model number of the inverter, M k is the model number of the inverter of the model K, The actual power of the m-th sample plate machine of the j-type k inverter of the photovoltaic power station, The correlation coefficient of the m-th sample plate machine of the j-type k inverter of the photovoltaic power station; the obtaining the coefficient matrix of the regression model according to the least square method specifically includes: according to the formula 2, the theoretical generated power of the photovoltaic power station is written into a matrix form of observation times: equation 2; Wherein e is the error term of the regression model, , , , Obtaining a loss function according to equation 3: equation 3; Order the According to the least square method, the coefficient matrix is obtained by the formula 4 as follows: equation 4; the obtaining the theoretical power generation of the current photovoltaic power station according to the current template inverter output through the linear regression model with the known correlation coefficient specifically comprises the following steps: if the photovoltaic module and the inverter are not overhauled at the current moment and the output of the template inverter is not limited, acquiring theoretical power generation through a formula 2; If the light rejection occurs and the output of the template inverter is not limited, the light rejection electric quantity is calculated according to the formula 5: Equation 5; Wherein, the The photo-electricity quantity is discarded for the photovoltaic power station j, The theoretical power generated by the photovoltaic power station j at the moment i, For the real power of the photovoltaic power station j at the moment i, n is the number of samples in the statistical period, Is the time resolution.
2. The method of claim 1, wherein said determining a template inverter for each different model of inverter comprises: The method comprises the steps of determining the template inverter, wherein the uniform distribution of the inverters of different types in different geographic positions, the inverter model, the battery plate type and the material characteristics are considered, and the number of the template inverter is one or more.
3. The method of claim 1, wherein the historical output of the photovoltaic power plant and the historical output data of the template inverter are first preprocessed before solving the correlation coefficients in the coefficient matrix according to the pre-acquired historical output of the photovoltaic power plant and the historical output of the template inverter, and if the historical output of the photovoltaic power plant and the historical output data of the template inverter exceed reasonable limit values, a future estimated value is adopted to replace the current value.
4. A photovoltaic power plant theoretical generated power calculation device based on a template inverter, characterized by comprising: The template module is used for dividing the total station inverter of the photovoltaic power station according to the model in advance and determining the template inverters of the inverters with different models; The coefficient matrix module is used for acquiring a coefficient matrix of the regression model according to a least square method based on a linear regression model of the theoretical power generation of the photovoltaic power station, which is established in advance and changes along with the output of the template inverter; the solving module is used for solving the correlation coefficient in the coefficient matrix according to the pre-acquired historical output of the photovoltaic power station and the historical output of the template inverter to acquire a regression model with known correlation coefficient; the calculation module is used for obtaining the theoretical power generation power of the current photovoltaic power station according to the current template inverter output through the linear regression model with the known correlation coefficient; The coefficient matrix module is specifically configured to: Obtaining a linear regression model according to equation 1: equation 1; Wherein P j is the theoretical generated power of the photovoltaic power station j, K is the model number of the inverter, K is the model number of the inverter, M k is the model number of the inverter of the model K, The actual power of the m-th sample plate machine of the j-type k inverter of the photovoltaic power station, The correlation coefficient of the m-th sample plate machine of the j-type k inverter of the photovoltaic power station; according to the formula 2, the theoretical generated power of the photovoltaic power station is written into a matrix form of observation times: equation 2; Wherein e is the error term of the regression model, , , , Obtaining a loss function according to equation 3: equation 3; Order the According to the least square method, the coefficient matrix is obtained by the formula 4 as follows: equation 4; The computing module is specifically configured to: if the photovoltaic module and the inverter are not overhauled at the current moment and the output of the template inverter is not limited, acquiring theoretical power generation through a formula 2; If the light rejection occurs and the output of the template inverter is not limited, the light rejection electric quantity is calculated according to the formula 5: Equation 5; Wherein, the The photo-electricity quantity is discarded for the photovoltaic power station j, The theoretical power generated by the photovoltaic power station j at the moment i, For the real power of the photovoltaic power station j at the moment i, n is the number of samples in the statistical period, Is the time resolution.
5. The apparatus of claim 4, wherein the template module is specifically configured to: The method comprises the steps of determining the template inverter, wherein the uniform distribution of the inverters of different types in different geographic positions, the inverter model, the battery plate type and the material characteristics are considered, and the number of the template inverter is one or more.

Description

Photovoltaic power station theoretical generation power calculation method and device based on template inverter Technical Field The document relates to the technical field of power system automation, in particular to a photovoltaic power station theoretical generation power calculation method and device based on a template inverter. Background The photovoltaic power generation system has poor peak regulation capability, the technical difficulty of grid connection and scheduling operation is high, and the randomness of the photovoltaic output provides challenges for the stable and economic operation of the power grid. The photovoltaic power generation has obvious timeliness, and has the characteristics of high output level in short time in midday, low output level in other time, output in daytime and regularity of no output in night. Due to the reasons of power grid peak regulation requirement, power transmission section limitation, maintenance of photovoltaic modules and the like, the output power of the photovoltaic power station needs to be limited in a special period on the basis of ensuring safe and stable operation of a power system. The theoretical power generation capacity and the light rejection capacity of the photovoltaic power station are reasonably and effectively calculated, the theoretical power generation capacity of the photovoltaic power station is mastered by a power grid dispatching department at the end of the light rejection period, the operation mode of a conventional unit is reasonably arranged, the reasonable arrangement of a production maintenance plan and the evaluation of the benefit of a power plant are facilitated for a power generation enterprise, and meanwhile, a basis is provided for the reasonable evaluation of electricity limiting measures and the electric quantity settlement of the power grid enterprise and the power generation enterprise. Disclosure of Invention The invention provides a photovoltaic power station theoretical generation power calculation method and device based on a template inverter, and aims to solve the problems. One or more embodiments of the present disclosure provide a photovoltaic power station theoretical generated power calculation method based on a template inverter, including: Dividing total-station inverters of a photovoltaic power station according to models in advance, and determining template inverters of different models; based on a linear regression model of the theoretical power generation power of the photovoltaic power station which is established in advance and changes along with the output of the template inverter, acquiring a coefficient matrix of the regression model according to a least square method; according to the historical output of the photovoltaic power station and the historical output of the template inverter which are obtained in advance, solving the correlation coefficient in the coefficient matrix, and obtaining a regression model with known correlation coefficient; and obtaining the theoretical power of the current photovoltaic power station according to the current template inverter output through a linear regression model with known correlation coefficients. One or more embodiments of the present specification provide a photovoltaic power plant theoretical generated power calculation apparatus based on a template inverter, including: The template module is used for dividing the total station inverter of the photovoltaic power station according to the model in advance and determining the template inverters of the inverters with different models; The coefficient matrix module is used for acquiring a coefficient matrix of the regression model according to a least square method based on a linear regression model of the theoretical power generation power of the photovoltaic power station, which is established in advance and changes along with the output of the template inverter; the solving module is used for solving the correlation coefficient in the coefficient matrix according to the pre-acquired historical output of the photovoltaic power station and the historical output of the template inverter to acquire a regression model with known correlation coefficient; And the calculation module is used for obtaining the theoretical power generation of the current photovoltaic power station according to the current template inverter output through a linear regression model with known correlation coefficients. According to the embodiment of the invention, the correlation coefficient in the coefficient matrix is solved according to the historical output and the historical output of the template inverter by establishing the established linear regression model of the theoretical power generation of the photovoltaic power station along with the output change of the template inverter, and then the theoretical power generation of the current photovoltaic power station is obtained according to the linear regression model with the k