The Study Of Rapid Setting Calculation In The Complex Ring Network

The fault analysis and calculation of the power system is a reference for the designing of the electrical equipment and grid connection mode. The fault analysis is also the important basis and the premise content of the setting calculation in the relay protection. With the expansion of the high voltage grid’s application scope, its structure is becoming more and more complex, and the operation mode is also diversity, which lead to the more points used to calculate the fault. In this case, it is a very difficult work if we use the traditional manual calculation method simply. It doesn’t only conform to the realistic situation, but also can’t satisfy the efficiency and accuracy of the fault calculation’s requirements. The above drawbacks can be overcomed by substituting the computer calculation for the past manual calculation. Thus, the fault calculation based on computer technology has become the developm-nt trend of the fault calculation in the power system.Short circuit calculation is the basis of all fault analysis and simulation, and the process relay protection setting calculation also needs the support of short circuit calculation. The most critical step in the short circuit calculation is building node impedance matrix. In the same situation, since the speed of the branch additional method to build the node impedance matrix is faster than the admittance inverse calculation, the branch additional method plays an important role in the short circuit calculation.In this paper, the fast algorithm of the setting calculation in the complex ring network based on the branch additional method is proposed. Firstly, according to the system’s request, the algorithm considers comprehensively the various operation m-odes of the circuit fault, and adopts the node impedance matrix as the mathematic model of the system. Then, we derive the fast setting calculation algorithm based on the branch additional method as the fast compensation and optimization algorithm of the impedance matrix, and then apply the generated protection setting value to the power system protection. Finally, taking the LuoHeBian in the2789line about Luo-Tao with220kV as example, we give the setting calculation accounts of the system to prove the correctness and reliability of the operation result. The work above prog-rammed by VisualC++6.0has been applied in anhui power grid, and its practice is proved its correctness.