Method and apparatus for generator control

A method of protecting a generator comprising the steps of:

• monitoring a rate of generator voltage change;
• monitoring a rate of generator current change;
• and
• reducing the generator output when a plurality of conditions are satisfied, the plurality of condition including the rate of generator voltage change exceeding a first level and the rate of generator current change exceeding a second level.

A method of protecting a generator having a field winding connected to a power supply comprising the steps of:

• detecting a generator voltage v;
• detecting a generator current i;
• differentiating the generator voltage v to obtain a quantity dv/dt;
• differentiating the generator current i to obtain a quantity di/dt;
• making a number of determinations including a first determination whether dv/dt is greater than a first value and a second determination whether di/dt is greater than a second value;
• and
• if each of the number of determinations is true, reducing a level of power supplied to the generator.

A control circuit for a generator having a field winding and an output comprising:

• a field transistor having a gate connected between the generator field winding and a ground;
• a field controller connected to the field transistor gate for controlling current flow through the field winding;
• a detector for determining a voltage change rate in the generator output and a current change rate in a generator current and producing a first output signal when the voltage change rate is above a first level and a second output signal when the current change rate is above a second level;
• and
• a generator controller operatively connected to said detector, said generator controller decreasing current flow through said generator field winding upon receipt of said first output signal and said second output signal.