Abstract: A UHV-LV interface circuit that is capable of the following, among other things: 1) starting up a primary controller of a power converter circuit with a precisely controlled startup charging profile; 2) performing pulse-based line-voltage sensing with reduced power and improved sensing accuracy; and 3) discharging a capacitor, e.g., class-X2 capacitor, with a stable supply voltage for the controller. The UHV-LV interface circuit can use a single UHV device, such as a single depletion-mode transistor, e.g., field-effect transistor (FET).

Abstract: A UHV-LV interface circuit that is capable of the following, among other things: 1) starting up a primary controller of a power converter circuit with a precisely controlled startup charging profile; 2) performing pulse-based line-voltage sensing with reduced power and improved sensing accuracy; and 3) discharging a capacitor, e.g., class-X2 capacitor, with a stable supply voltage for the controller. The UHV-LV interface circuit can use a single UHV device, such as a single depletion-mode transistor, e.g., field-effect transistor (FET).

Abstract: An analog controller is disclosed. The controller has a maximum power point tracking unit and a power factor adjusting unit. The maximum power point tracking unit generates a maximum power tracking voltage which is used to control the magnitude of the output current of the inverter so as to extract the most available power from the power generating device. The power factor adjusting unit, which generates a ramp control voltage that will further determine the duty ratio and switching frequency of PWM signal, gracefully tunes the magnitude and reduces the total harmonic distortion of the current injected from inverter into utility grid.

Abstract: The present invention discloses an analog controller for an inverter. The controller has a maximum power point tracking unit and a power factor adjusting unit. The maximum power point tracking unit generates a maximum power tracking voltage which is used to control the magnitude of the output current of the inverter so as to extract the most available power from the power generating device. The power factor adjusting unit, which generates a ramp control voltage that will further determine the duty ratio and switching frequency of PWM signal, gracefully tunes the magnitude and reduces the total harmonic distortion of the current injected from inverter into utility grid.