Direct current power plant

Method of delivering power to an electric grid comprising:

• driving a generator;
• obtaining AC power from the generator;
• converting the AC power to DC power;
• providing the DC power to the electric grid;
• receiving an angle from a sawtooth waveform generator;
• representing the angle by a 16-bit value, the angle having a sine and a cosine;
• applying an average increment to the angle, as an angle sweeps from 0-360°, every 100 μsecs, the average increment having a 32-bit center frequency input and a 16-bit delta frequency input driven by a PI controller, the center frequency input representing a fractional value of the angle, the delta frequency oscillating about zero;
• producing a sine/cosine pair for the angle;
• creating an inverter output waveform based on the sine/cosine pair;
• computing a phase error signal based on the sine of the angle and a voltage of a grid supply, the voltage of a grid supply being equal to the cosine of the voltage of the grid supply;
• multiplying the sine by the voltage of the grid supply to produce a signal that contains both AC and DC components, the AC component having an amplitude variation based on amplitudes of the grid supply and the inverter output waveform and having a frequency equal to 2× the frequency of the grid supply when loop is locked, the DC component having an amplitude variation based on a phase error between the grid supply and the inverter output waveform;
• low pass filtering the phase error;
• and
• eliminating a part of the AC component not relevant to control by supplying the filtered phase error to the PI controller.