Low-loss zero current switching shunt regulator for ac alternator

摘要

A control circuit (30) for use with an AC alternator (22) has a plurality of outlet lines (26A,26B,26C) leading from the alternator, each receiving a phase of current generated by the alternator (22). Tap lines (30A,30B,30C) are associated with each of the power lines and are associated with a switch (32A,32B,32C). The switches drain power to a drain (36) when in a first state, and allow the power to pass downstream to a system load (28) when in a second state. A switch control (40,42) changes the switches (32A,32B,32C) between the first and second state. A detector (38) detects when the current signal is approaching a zero crossing between a cycle positive portion and a negative portion. The switch control (40,42) takes in the information with regard to the approaching zero crossing, and change the switches (32A,32B,32C) between the first and second states based upon the detected zero crossing point. An alternator (22) is also disclosed.