CPC H02P 1/426 (2013.01) [H02P 27/08 (2013.01)] | 17 Claims |
1. A system comprising:
an AC electric motor of the single-phase induction type;
the AC electric motor having a start winding, and a run winding;
an AC input connection;
a variable frequency motor (VFD) drive having at least a first and a second phase output, the VFD drive coupled to be powered by a solar panel input;
a contactor having at least a first and a second setting;
wherein, with the contactor in the first setting, at least one output of the VFD is connected across the run winding of the AC electric motor; and
with the contactor in the second setting, the run winding of the AC electric motor is coupled to the AC input connection and the start winding of the AC electric motor is coupled through a capacitor and start switch to the AC input connection;
wherein the system is configured to, upon determining that the motor has started rotating, setting the contactor in the first setting, the variable frequency motor drive thereupon being configured to continue running the motor by applying AC voltage across running winding only, the VFD drive configured to use power from the solar panel input; and
when the AC electric motor is not rotating, and motor operation is desired, the system is configured to periodically measure an available solar power and to start the AC electric motor if the available solar power is greater than a first threshold power determined to be sufficient to run the AC electric motor.
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