Simulation And Study On Power Grid Wide-area Backup Protection Based On PSCAD

As the grid structure becomes more complex,the settings and delay of each level of protection are becoming increasingly large.And due to the poor adaptability of traditional relay protection,when the network topology changing,traditional relay protection is quite likely to be mishandled or rejected.With the continuous popularization of power digital technology and communication technology,People gradually began to pay more attention to wide-area backup protection based on wide area communication networks Study.The wide area relay protection collects a plurality of grid circuit breakers status information,via the communication module,and transmit to an intelligent electronic device.With the analysis of the obtained information,the intelligent electronic device can locate the fault and make the correct Corresponding action signals,which are then transmitted to the circuit breakers through the communication module,to achieve faster and minimal area of fault isolation,and to ensure reliable and safe operation of the power grid.This paper elaborates on the wide-area backup protection of power systems.The working characteristics,advantages and disadvantages of the currently used three wide-area backup protection architectures are analyzed.This paper also introduce a kind of power grid wide-area backup protection algorithm based on correlation matrix in detail.The algorithm introduces the circuit breaker status,switching action and direction information,defines the related correlation coefficients,and presents a matrix criterion based on the correlation coefficients.By calculating the sum of the elements in each row of the matrix and comparing it with the threshold value,the fault line can be accurately judged,which is simple and reliable.Treated as the research object of large power grids,IEEE10 machine 39 nodes grid model is built under PSCAD software,with distance protection and direction protection components.Then simulate various types of faults to verify the correctness and fault tolerance of the relevant matrix power grid wide area backup protection algorithm,even in the case of distortion.