PSSE Webinar-III : Power Flow Analysis Solution Techniques in PSS/E

In PSS®E there are many power flow solution methods available to solve the steady-state power flow analysis. Each method uses iterative techniques to solve the power system nonlinear algebraic equations by adjusting voltages at all systems buses to satisfy Kirchhoff’s current laws and system demand as well. Moreover, the real and reactive power mismatch practically should be zero (with small tolerance) at each bus and the total system generation should be balanced with system demand. • In PSS/E the regular Gauss-Seidel methods and modified Gauss-Seidel are available. Both these methods are fast per iteration basis, but the convergence time is slower than the Newton-Raphson methods. • Similarly, the PSS/E include the Newton Raphson methods comprises o Full Newton-Raphson o Decoupled Newton-Raphson o Fixed-slope Decoupled Newton-Raphson Above mentioned methods use the first-order Taylor series expansion of the load flow equations and with the use of Jacobian Matrix and the iterations are continued until system convergence reached. However, the time to reach the solution in these methods is fast as compare to the Gauss-Seidel method. So, in this regard power system engineer is required to perform training exercises to find the optimum combination of these iterative methods for every network model.