Power supply circuits

A photovoltaic power conditioning circuit for providing power from a photovoltaic device to an alternating current (AC) mains power supply line, the photovoltaic power conditioning circuit comprising:

• a DC input to receive DC power from the photovoltaic device;
• an AC output configured for direct connection to the AC mains power supply line;
• a DC-to-AC converter coupled to the DC input and to the AC output configured to convert DC power from the photovoltaic device to AC power for output onto the AC mains power supply line;
• an electronic controller directly coupled to the AC mains power supply line configured to measure a voltage of the AC mains power supply line and a current from the DC-to-AC converter and to control the DC-to-AC converter responsive to the measuring;
• a maximum power point tracking (MPPT) circuit coupled to the DC input;
• and
• a rechargeable battery interface with an input coupled to an output of the MPPT circuit.

A method of conditioning power from a photovoltaic device for provision to an alternating current (AC) mains power supply line, the method comprising:

• reading data for a voltage on the AC mains power supply line and a current into the AC mains power supply line at an electronic controller;
• determining a first frequency for the voltage and a second frequency for the current using the electronic controller;
• and
• conditioning the power using the electronic controller responsive to a difference between the first and second frequencies.

A power conditioning integrated circuit for providing power to an alternating current (AC) mains power supply line from a photovoltaic device, the power conditioning circuit comprising:

• a first AC stage configured to convert direct current (DC) power from the photovoltaic device to a first AC power, the first AC stage comprising a plurality of metal-oxide-semiconductor field-effect transistors (MOSFETs);
• and
• a second AC stage that operates at a higher voltage than the first AC stage configured to convert the first AC power to a second AC power, the second AC stage comprising a plurality of insulated gate bipolar transistors (IGBTs), wherein a portion of the first AC stage is electrically isolated from the second AC stage;
• wherein the power conditioning integrated circuit is a silicon-on-insulator integrated circuit comprising a buried oxide layer, and wherein the first AC stage is electrically isolated from the second AC stage with a dielectric filled trench on the power conditioning integrated circuit extending down to contact the buried oxide layer.