The 'idea' of affecting the electrically charged particles within the flame is very accurate science. Indeed we are (or should be) fully aware of how we already extinguish fires by affecting these particles. Dry powder does just that, it breaks down into 'free radicals' - i.e. +ve and -ve charged particles which can them react with any others around. They then undergo a chemical reaction with those in the flame (which is the combustion area) in a much less exothermic and not light-emitting one than the combustion one. An electrical field should be able to do the same by taking out one side of the chemical reaction through neutralising the +ve, or -ve charged radicals. Of course managing to do this in a controlled laboratory environment is quite different to producing a practical real world example.
