Alternating current line type and parameter identification method based on identification parameter projection

Abstract

The invention discloses an alternating current line type and parameter identification method based on identification parameter projection belonging to the electric power system planning field. The method is characterized by through a resistance, a reactance and a susceptance parameter of one alternating current line, expressing as one parameter vector P(x, y, z), defining as a representative vector of the line and converting into two included angle vectors alpha (theta1, theta2); reading electrical parameter data of an alternating current line in a planning power grid; carrying out data preprocessing; reading a resistance, a reactance and a susceptance parameter value of each alternating current line and forming the parameter vector P(x, y, z) of each alternating current line so that the parameter vectors of all the alternating current lines form a sample point set P to be identified; and calculating included angle vectors of all the sample point sets P to be identified, forming an included angle vector set phi, marking the point whose line included angle exceeds a threshold thetas as an abnormal point in each type, and identifying an alternating current line type and parameters. Therefore, the method is used to establish a basis for further identifying error or unreasonable parameters. Work efficiency and efficacy are increased.

Description

technical field [0001] The invention belongs to the field of power system planning, in particular to an identification method for AC line types and parameters based on identification parameter projection. Background technique [0002] In our country, BPA (power system analysis software) software is widely used in the process of power system planning, which has many advantages such as good convergence and fast calculation speed. However, the AC line in BPA is represented by L card. One L card is an AC line. The parameters contained in the L card include the bus at the beginning and end of the line, the reference voltage at the beginning and end of the line, the resistance, reactance, and conductance to ground of the line. , susceptance to ground, line length, etc. For power flow calculation in power grid planning, reactance parameters are mandatory, otherwise the power flow calculation cannot be performed; resistance and susceptance parameters also need to be filled in, but ...

AI Technical Summary

Problems solved by technology

For power flow calculation in power grid planning, reactance parameters are mandatory, otherwise the power flow calculation cannot be performed; resistance and susceptance parameters also need to be filled in, but they are not mandatory, otherwise there will be deviations in the calculation results; for the conductance of overhead lines Parameters are generally not filled in in BPA, so they are generally not considered in the process of AC line parameter identification

[0003] In the actual power grid planning work, it is easy to fill in the wrong parameters in the L card of the AC line. In the process of manually adding and modifying data, it is very easy to miss and fill in the wrong situation; second, the limitation of BPA itself, the number of digits occupied by each parameter in the line L card is limited, for example, the line reactance parameter value is in L The card occupies 6 bytes. If the reactance value exceeds the limit length during the filling process, the parameter items filled in later will be displaced, and then all the parameter values ​​​​filled in later will be wrong; 3. Some items in some cards in BPA use Automatically control the accuracy, for example, the default accuracy of the line length item in the line L card is F4.1, that is, if the filled value is 1111 without adding a decimal point, then BPA automatically recognizes it as 111.1, which can easily cause parameter filling errors

The above three reasons have resulted in a considerable amount of wrong data in the AC line parameters of the planned grid

These have caused certain difficulties and deviations in the convergence and convergence results of power flow calculations in grid planning

[0004] The wrong or unreasonable data caused by the above problems will have a great impact on the convergence and results of the power flow calculation of the planned power grid

First of all, wrong and unreasonable data will affect the convergence of power flow calculations and increase the workload of planners in adjusting power flows; secondly, wrong and unreasonable data will affect the accuracy of power flow calculation results, which may lead to large deviations between grid planning results and actual results. Far, resulting in greater economic waste, what's more, it may bury hidden dangers to the safety of the power grid

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