A circuit for use with an AC alternator comprising: a plurality of outlet lines (26A,26B,26C) leading from the alternator, each receiving a phase of current generated by the alternator; tap lines (30A,30B,30C) associated with each of said outlet lines (26A,26B,26C), said tap lines each being associated with a MOSFET switch (32A,32B,32C); a current sense is positioned between said MOSFET switches (32A,32B,32C) and a zero crossing detector, and downstream of said MOSFET switches to provide a current signal to a control circuit for each of said tap lines; said MOSFET switches (32A,32B,32C) being operable to drain power to a drain when in a first state, and to allow the power to pass downstream to a system load, if an output voltage is not higher than a desired voltage, when in a second state; a switch control (40,42) for controlling the MOSFET switches (32A,32B,32C) to change between the first and second state; and the zero-crossing detector positioned to receive signals from said tap lines for detecting when each of the current signals through the associated MOSFET switch (32A,32B,32C) is approaching a zero crossing between a positive portion and a negative portion, and said switch control (40,42) being operable to take in the information with regard to the approaching zero crossing, and change one of the MOSFET switches (32A,32B,32C) associated with a particular tap line having the current signal approaching the zero crossing, between the first and second states, so as to drain the negative portion of the current signal, or to drain some positive portion of the current signal if the output voltage is higher than the desired voltage. a plurality of outlet lines (26A,26B,26C) leading from the alternator, each receiving a phase of current generated by the alternator; tap lines (30A,30B,30C) associated with each of said outlet lines (26A,26B,26C), said tap lines each being associated with a MOSFET switch (32A,32B,32C); a current sense is positioned between said MOSFET switches (32A,32B,32C) and a zero crossing detector, and downstream of said MOSFET switches to provide a current signal to a control circuit for each of said tap lines; said MOSFET switches (32A,32B,32C) being operable to drain power to a drain when in a first state, and to allow the power to pass downstream to a system load, if an output voltage is not higher than a desired voltage, when in a second state; a switch control (40,42) for controlling the MOSFET switches (32A,32B,32C) to change between the first and second state; and the zero-crossing detector positioned to receive signals from said tap lines for detecting when each of the current signals through the associated MOSFET switch (32A,32B,32C) is approaching a zero crossing between a positive portion and a negative portion, and said switch control (40,42) being operable to take in the information with regard to the approaching zero crossing, and change one of the MOSFET switches (32A,32B,32C) associated with a particular tap line having the current signal approaching the zero crossing, between the first and second states, so as to drain the negative portion of the current signal, or to drain some positive portion of the current signal if the output voltage is higher than the desired voltage.