Simulation of transients in very large scale distribution networks by combining input text files with graphical user interface

A large scale distribution network with secondary grid network details can easily have ten thousands of nodes and become very complex to study using an Electromagnetic Transients Type (EMT-type) tool. This paper promotes a mixed design tool that connects "visually built" parts with the rest of the network maintained with text files. This approach allows quickly modifying the distribution network built with full details in a transient simulation environment while improving the simulation experience in many ways. Having full circuit details allows the initialization of transient analysis with correct multiphase load flow solution. Once the full circuit simulations are available it is possible to tune equivalent circuits and evaluate the order of approximation errors. A real North American urban distribution network is studied as an example in this paper. Both steady state and transient analysis are performed. Capacitor switching at the substation level is the transient phenomenon studied. A discussion on available guides and technical documents related to switching of shunt capacitors is provided in conjunction with the simulation results.