2. What are simulators for?

2.1 When and why did the need arise?

The need to model networks in order to simulate their dynamic operation undoubtedly goes back to the origins of electrical networks themselves. The first simulators were analog simulators in which reduced models of networks (represented by elementary components R, L, C ) and rotating machines were used to better predict or understand system behavior under dynamic conditions. They were also used to meet certain needs, such as the development and testing of control and protection equipment. Many analog simulators of this generation, operating in real time and comprising up to several dozen synchronous machines, are still in use today. Digital, computer-based simulators first appeared in the 1960s.

It's worth noting that major...