What are the types of voltage regulator circuits that can be used to regulate voltages in the range of 200 - 240 Volts? I need a circuit that will prevent the voltage from exceeding a value of about 210 volts.
I'm not sure if a simple clipper circuit will work in this instance. Is there a way to adapt one for this voltage range?

 

multi tap transformers. Although not 'regulators', you can select your voltage within some percentage to accomodate your requirements.

 

Are those expensive? If so, is there any electronic (semiconductor based) method I can use?

 

Constant voltage transformers.

 

I think mains-connected semiconductors would be a prohibited topic here anyway.

 

Big transformers are expensive, but you didn't say if you need 100 amps or 100 milliamps.

 

I need very small currents.. just enough to charge a 330 uF capacitor in say.. 10 seconds..