Single Phase Current Source Power Inverters and Related Methods

An apparatus comprising:

• a DC source port comprising:
• a first DC source terminal;
• and
• a second DC source terminal;
• a first switch;
• a second switch;
• a third switch wherein first terminals of the first, second, and third switches are coupled together;
• a first feedback loop from a second terminal of the first switch to the first terminal of the first switch;
• a second feedback loop from a second terminal of the second switch to the first terminal of the second switch;
• a third feedback loop from a second terminal of the third switch to the first terminal of the third switch;
• a first inductor coupled between the first DC source terminal and the first terminals of the first, second, and third switches;
• a power grid port comprising:
• a first power grid terminal;
• and
• a second power grid terminal;
• a first electrical path between the first feedback loop and the first power grid terminal;
• a second electrical path between the second feedback loop and the second power grid terminal;
• a first capacitor;
• a third electrical path through the first capacitor and between the third feedback loop and the second power grid terminal;
• a second inductor between the first feedback loop and the first power grid terminal;
• and
• a second capacitor between the first feedback loop and the second power grid terminal;
• wherein:
• the first, second, and third switches are configured to distribute portions of a DC link current through the apparatus;
• the first capacitor is larger than the second capacitor;
• the first inductor is larger than the second inductor;
• power ratings of the first and second switches are greater than a power rating of the third switch;
• at least one of the first, second, and third switches comprises at least one of a GTO switch, an IGBT switch, a BJT switch, a bipolar transistor switch, a field effect transistor switch, or a MOSFET switch;
• the first inductor comprises an inductance of between approximately 1 millihenry and approximately 10 millihenries;
• the first capacitor comprises a capacitance of between approximately 100 microfarads and approximately 200 microfarads;
• and
• the third switch is configured to route an alternating current portion of the DC link current through the first capacitor to attenuate a current ripple effect of the DC link current and improve a maximum power point tracking of the apparatus.

A method comprising:

• routing power from a DC source to a power grid via a single phase current source inverter;
• attenuating a variable component of the power to improve a maximum power point tracking of the current source inverter, wherein attenuating the variable component of the power comprises maintaining an approximate target magnitude and an approximate target phase of a reactive current of the DC link current to maintain a magnitude of the variable component of the power at or proximate to zero;
• and
• providing the single phase current source inverter, wherein providing the single phase current source inverter comprises:
• providing a first inductor coupled to a switch set;
• providing a first DC source terminal of the DC source coupled to the first inductor;
• providing a first switch of the switch set coupled to a first power grid terminal of the power grid;
• providing a second switch of the switch set coupled to a second power grid terminal of the power grid;
• and
• providing a first capacitor coupled between a third switch of the switch set and the second power grid terminal of the power grid.

A bridge circuit comprising:

• a DC source port comprising:
• a first DC source terminal;
• and
• a second DC source terminal;
• a switch set comprising at least three switches coupled together;
• a first inductor coupled between the first DC source terminal and the switch set;
• a power grid port comprising:
• a first power grid terminal coupled to a first switch of the switch set;
• and
• a second power grid terminal coupled to a second switch of the switch set;
• a first capacitor coupled between a third switch of the switch set and the second power grid terminal;
• a first electrical path between a second terminal of the first switch and the first power grid terminal;
• a second electrical path between a second terminal of the second switch and the second power grid terminal;
• and
• a third electrical path via the first capacitor between a second terminal of the third switch and the second power grid terminal;
• wherein:
• the first and second DC source terminals are configured to couple the bridge circuit to a DC source;
• the first inductor is coupled to first terminals of the first, second, and third switches;
• and
• the first capacitor is coupled between the second terminals of the second and third switches.