Quality power from induction generator feeding variable speed motors

aaaaaA prime mover in a heat recovery system drives an induction generator which feeds power to a utility grid through a breaker but also powers a load including auxiliary induction motors. To provide acceptable waveform and power factor, the auxiliary equipment is driven through IGBT switched bridge converters by DC voltage generated by an IGBT switched bridge converter, instead of three-phase diode rectifiers. The switched bridge converter controller is responsive to a system process controller which causes the switched bridge controller to be driven in response to the voltage and current on the generator bus. This eliminates the need for harmonic filters and power factor capacitors while improving the quality of the power generated. The controller trips the breaker if the voltage, frequency or power factor is out of limits.