Power system analiysis using state space techniques

In power systems, in addition the voltages as a result of the external effects, such as lightning surges initiated as a result of atmospheric discharges, overvoltages and overcurrents are resulted due to switching events, short-circuit faults, loss of load and Ferranti effects in unloaded transmission lines. Accurate determination of transient voltages and currents is important for the design of protection equipment and isolation coordination. In this study, transient current and voltages after line energization are computed using state-space techniques. State equations describing the system are formulated and these equations are solved analytically and also using different numerical integration methods such as Euler method, Runge Kutta method and Trapezoidal rule of integration. Stability of the systems studied is investigated. The results obtained using state-space techniques are compared with those obtained using EMTP-ATP. The state-space techniques are found suitable for transient analyses in power systems.