Essentially, you have two sentences:
In recent years some new models have been proposed.
Each one has its own advantages and disadvantages.
Trying to combine the two into a single sentence with a comma is awkward. It's usually regarded as an error in technical writing. There are several ways to combine the two sentences. Here are some examples:
Using "and":
In recent years some new models have been proposed, and each one has its own advantages and disadvantages.
Using a semicolon:
In recent years some new models have been proposed; each one has its own advantages and disadvantages.
Using a participial clause (which is what your editor chose):
In recent years some new models have been proposed, each one having its own advantages and disadvantages.
Turning the second sentence into a participial clause allows the two ideas to stay together in the same sentence because a participial clause functions as an adverb (or an adverbial clause). To be precise, this is called an absolute clause. Also related: choster's answer.