Abstract: Transformers and methods of constructing transformers are disclosed. In one embodiment, a method of constructing a transformer includes wrapping a first primary winding around a core, wrapping a secondary winding around the core, and wrapping a second primary winding around the core. The first primary winding traverses substantially an entire circumference of the core in a first circumferential direction. The secondary winding includes a first half and a second half. The first half traverses substantially the entire circumference of the core in the first circumferential direction, and the second half traverses substantially the entire circumference of the core in a second circumferential direction opposite the first circumferential direction. The second primary winding traverses substantially the entire circumference of the core in the second circumferential direction.

Abstract: Photovoltaic power converter systems and methods are described. In one example, a method for use in operating a solar power converter includes sampling a DC link voltage of a DC link during a first cycle of an alternating output voltage of a second stage at one instance when the alternating output voltage is crossing zero volts in a first direction. A voltage difference a voltage difference between the DC link voltage sampled during the first cycle and a DC link voltage sampled during a previous cycle when the alternating output voltage was crossing zero volts in the first direction is determined. A DC link power is estimated based at least in part on the determined voltage difference. The AC power output by the second stage in a second cycle is controlled based at least in part on the estimated DC link power.

Abstract: Photovoltaic (PV) power converters including an LLC converter stage are described. A PV power converter includes a LLC converter stage and a controller. The LLC converter stage includes an input for receiving a direct current (DC) power input from a PV module, a first transformer having a primary winding and a secondary winding and defining a DC side and an alternating current (AC) side of the PV power converter, a plurality of switches on the DC side of the first transformer, and an output coupled to the secondary winding of the first transformer to provide a DC power output. The plurality of switches is coupled between the primary winding of the first transformer and the input. The controller is located on the AC side of the PV power converter. The controller is operatively connected to the plurality of switches and configured to control operation of the plurality of switches.

Abstract: An AC photovoltaic module includes a DC photovoltaic module for converting solar energy to DC electrical power, and an inverter for converting DC electrical power to AC electrical power, the inverter being adapted for connection to a frame portion of the module and being sized and configured, and provided with arrangements of electrical components thereof, to dispense heat from the inverter, whereby to prolong operational life and reliability of the inverter.

Abstract: Power converters and methods of recovering leakage energy in power converters are disclosed. In one embodiment, a power converter assembly includes an input for receiving a direct current (DC) power input, a flyback converter coupled to the input, and a leakage energy recovery circuit coupled to the flyback converter. The flyback converter includes a transformer having a plurality of windings.

Abstract: Soft switching power converters are described. In one example, a solar power converter includes an inverter input to receive a direct current (DC) power input and an output to provide an alternating current (AC) power output. The converter includes a first and a second power branch, and a controller. The first power branch includes a plurality of first switches and a first current sensor configured to generate a first current signal. The second power branch includes a plurality of second switches and a second current sensor configured to generate a second current signal. The controller is configured to control switching of the first and second plurality of switches to provide the AC power output based at least in part on the first and second current signals.

Abstract: Photovoltaic power converter systems and methods are described. In one example, a method for use in operating a solar power converter includes sampling a DC link voltage of a DC link during a first cycle of an alternating output voltage of a second stage at one instance when the alternating output voltage is crossing zero volts in a first direction. A voltage difference a voltage difference between the DC link voltage sampled during the first cycle and a DC link voltage sampled during a previous cycle when the alternating output voltage was crossing zero volts in the first direction is determined. A DC link power is estimated based at least in part on the determined voltage difference. The AC power output by the second stage in a second cycle is controlled based at least in part on the estimated DC link power.

Abstract: Transformers and methods of constructing transformers are disclosed. In one embodiment, a method of constructing a transformer includes wrapping a first primary winding around a core, wrapping a secondary winding around the core, and wrapping a second primary winding around the core. The first primary winding traverses substantially an entire circumference of the core in a first circumferential direction. The secondary winding includes a first half and a second half. The first half traverses substantially the entire circumference of the core in the first circumferential direction, and the second half traverses substantially the entire circumference of the core in a second circumferential direction opposite the first circumferential direction. The second primary winding traverses substantially the entire circumference of the core in the second circumferential direction.

Abstract: An AC photovoltaic module includes a DC photovoltaic module for converting solar energy to DC electrical power, and an inverter for converting DC electrical power to AC electrical power, the inverter being adapted for connection to a frame portion of the module and being sized and configured, and provided with arrangements of electrical components thereof, to dispense heat from the inverter, whereby to prolong operational life and reliability of the inverter.

Abstract: Soft switching power converters are described. In one example, a grid tie solar power converter includes an input for receiving a direct current (DC) power input, an h-bridge coupled to the input, and an output coupled to the h-bridge. The h-bridge includes a plurality of power switches. The output includes a first output node and a second output node. The converter also includes a first output inductor coupled between the h-bridge and the first output node, a second output inductor coupled between the h-bridge and the second output node, and a soft switching circuit coupled to the first output inductor and the second output inductor. The soft switching circuit is configured to facilitate zero voltage switching of the plurality of switches of the h-bridge.

Abstract: An AC photovoltaic module includes a DC photovoltaic module for converting solar energy to DC electrical power, and an inverter for converting DC electrical power to AC electrical power, the inverter being adapted for connection to a frame portion of the module and being sized and configured, and provided with arrangements of electrical components thereof, to dispense heat from the inverter, whereby to prolong operational life and reliability of the inverter.

Abstract: An AC photovoltaic module includes a DC photovoltaic module for converting solar energy to DC electrical power, and an inverter for converting DC electrical power to AC electrical power, the inverter being adapted for connection to a frame portion of the module and being sized and configured, and provided with arrangements of electrical components thereof, to dispense heat from the inverter, whereby to prolong operational life and reliability of the inverter.