Here's the deal. The textbook I am using (Nilsson and Riedel, Electric Circuits, 9th Ed) has a chapter regarding two-port networks and there are a couple of things that don't make a lot of sense to me. In particular, they state that the first restriction on a block that is to be modeled as a two-port network is that it can have no energy stored within it (note that this is in addition to the restriction that it can't have any independent sources, so that isn't what they are referring to).
They don't clarify it any more than that (that I can see). In particular, they don't explain the reason for ANY of the restrictions, which is frustrating. But this restriction would seem to indicate that there can't be any reactive elements with a two-port network, yet that would not only seem to defeat much of the utility, but it is also counter to many of the networks that they have in the problems for the chapter. So just what are they talking about?
I have to admit that I have done very little directly with two-port networks (though certainly many of the things I have done over the years would probably fall into this category if looked at the right way). In looking over information online, I can't find any place else that places this same restriction on the circuits in such a network, at least not in so many words. So I'd like to get some of your thoughts on the matter.
Thanks.
They don't clarify it any more than that (that I can see). In particular, they don't explain the reason for ANY of the restrictions, which is frustrating. But this restriction would seem to indicate that there can't be any reactive elements with a two-port network, yet that would not only seem to defeat much of the utility, but it is also counter to many of the networks that they have in the problems for the chapter. So just what are they talking about?
I have to admit that I have done very little directly with two-port networks (though certainly many of the things I have done over the years would probably fall into this category if looked at the right way). In looking over information online, I can't find any place else that places this same restriction on the circuits in such a network, at least not in so many words. So I'd like to get some of your thoughts on the matter.
Thanks.