What is wrong with line-type modulators?

A number of architectures for modulators have been generated since the line-type modulator was developed. Each design approach offers advantages and disadvantages for a given application. Recent designed architectures include IGBT-switched capacitor banks, IGBT-switched induction adders, and IGBT-switched fractional turn transformers. This paper takes a brief look at these three modulator approaches, briefly describes them, considers their relative advantages and disadvantages, compares them with an SCR switched PFN, and attempts to answer the question: What is wrong with line-type modulators?.