An apparatus for regulating a transient response of an output signal of an electrical generator. The apparatus comprises a tapped output winding means for providing a first AC signal and a second AC signal. The first and second AC signals have respective RMS values. The RMS value of the first AC signal is greater than the RMS value of the second AC signal. An AC switching means for selecting between the first AC signal or the second AC signal, and thereby providing a switched AC signal which has a duty cycle. A rectifier means for rectifying the switched AC signal and providing a rectified DC signal. The rectified DC signal has a DC signal component, a square wave signal component and a ripple signal component. The square wave signal component has a duty cycle. The duty cycle of the square wave signal component is equal to the duty cycle of the switched AC signal. A filter means for filtering the rectified DC signal and for providing the output signal. The filter means is operable to filter the rectified DC signal by averaging the square wave component and filtering the ripple component. The AC switching means is responsive to the output signal to adjust the duty cycle of the switched AC signal to regulate the output signal.