Power converter using wide band-gap devices

An electrical power conversion system comprising:

• a first converter stage electrically coupled with a PV source, the first stage including a first switching device and being operable to boost DC power received from the PV source;
• a second converter stage electrically coupled in series with the first converter stage, the second converter stage including second and third switching devices operably coupled with a resonant circuit network and being operable to boost DC power received from the first converter stage;
• a third converter stage electrically coupled with the second converter stage and electrically coupled with an AC electrical power system, the third stage including an inverter bridge including a plurality of inverter switching devices;
• and
• an electronic control system structured to
• receive as input information of a voltage (Vpv) and a current (lpv) that are output by the PV source to the first converter stage, information of a voltage (Vdc) output by the second controller stage to the third controller stage, and information of a voltage (Vac) and a current (lac) which are output by the third stage to the AC electrical power system,
• process the information of (Vpv) and (lpv) to provide a control command for the first switching device,
• process the information of (Vdc, Vac) and (lac) to provide control commands for the plurality of inverter switches, and
• provide control commands for the second and third switching devices utilizing a predetermined duty cycle effective to provide resonant frequency operation of the second and third switching devices.

A method for converting power from a DC power source, comprising:

• operating, with an electronic control system, a first converter stage including a first switching device, a second converter stage electrically coupled in series with the first converter stage including second and third switching devices, and a third converter stage including an inverter bridge including a plurality of inverter switching devices;
• receiving, with the electronic control system, input information of a voltage (Vpv) and a current (lpv) that are output by the DC source to the first converter stage, information of a voltage (Vdc) output by the second controller stage to the third controller stage, and information of a voltage (Vac) and a current (lac) which are output by the third stage to the AC electrical power system;
• processing, with the electronic control system, the information of (Vpv) and (lpv) to provide a control command for the first switching device so as to reduce fluctuation of (Vpv);
• processing, with the electronic control system, the information of (Vdc, Vac) and (lac) to provide control commands for the plurality of inverter switches;
• and
• providing, with the electronic control system, control commands for the second and third switching devices utilizing a predetermined duty cycle effective to operate the second and third switching devices at a resonant frequency.