	US 12,352,230 B2
	Direct current power plant
Andrew A. Schnellinger, Merrimack, NH (US); James R. Lowell, Goffstown, NH (US); Bryan A. Finseth, Newbury, NH (US); Christopher L. Barber, Exeter, RI (US); Jason M. Sachs, Chandler, AZ (US); Donald J. Lucas, Windham, NH (US); Shannon Prescott, Loudon, NH (US); Jeffrey W. Kite, Manchester, NH (US); Andras K. Fekete, Fremont, NH (US); and Douglas R. Adams, Pepperell, MA (US)
Assigned to DEKA Products Limited Partnership
Filed by DEKA Products Limited Partnership, Manchester, NH (US)
Filed on Nov. 20, 2023, as Appl. No. 18/514,452.
Application 17/748,458 is a division of application No. 16/990,140, filed on Aug. 11, 2020, granted, now 11,339,758, issued on May 24, 2022.
Application 16/990,140 is a division of application No. 16/243,846, filed on Jan. 9, 2019, granted, now 10,760,541, issued on Sep. 1, 2020.
Application 16/243,846 is a division of application No. 15/182,147, filed on Jun. 14, 2016, granted, now 10,215,146, issued on Feb. 26, 2019.
Application 18/514,452 is a continuation of application No. 17/748,458, filed on May 19, 2022, granted, now 11,859,589.
Claims priority of provisional application 62/182,182, filed on Jun. 19, 2015.
Claims priority of provisional application 62/188,240, filed on Jul. 2, 2015.
Prior Publication US 2024/0093663 A1, Mar. 21, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. F02N 11/08 (2006.01); F02G 1/043 (2006.01); F24D 11/00 (2022.01); H02J 1/10 (2006.01)

CPC F02N 11/0859 (2013.01) [F02G 1/043 (2013.01); F02N 11/0866 (2013.01); F24D 11/00 (2013.01); H02J 1/10 (2013.01); F02G 2275/40 (2013.01); F02N 2011/0885 (2013.01)]

44 Claims

1. 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.