Modelling and Simulation of a Variable Step Size Algorithm for a Power Simulator

Abstract

The Dispatcher Training Simulator (DTS) is used for imparting training in power system operation and allied areas. It facilitates the dispatcher to be trained in normal, emergency and restorative conditions. A numerically stable algorithm that can accommodate larger time step width will be an ideal choice for DTS, but it should also have smaller time step width to capture short term dynamics. Hence, an algorithm has been developed, for simulation of long-term dynamics at a ‘larger time step width’, in order to decrease the total simulation time while the simulation is made to run for a 24 hour system load curve and also to capture the short term dynamics with a ‘small time step width’. To these authors’ knowledge the approach used in this algorithm has not been used elsewhere. This article presents the modelling and simulation of a variable step size algorithm for a DTS. Long-term dynamics gives an observable system response, which can be used to train system operators. Short-term dynamics gives the transient stability of the system. An efficient Network Topology Processor and apt component models were interfaced with this algorithm. This algorithm has been implemented in a DTS - Power System Simulation Module and tested for many possible cases like, Bus fault application and removal, Line opening and closing, etc.