AC-to-DC power conversion with ground reference to common node of solid-state AC switch

A device, comprising:

• a solid-state alternating current (AC) switch comprising a first solid-state switch and a second solid-state switch which are coupled back-to-back to a common node of the solid-state AC switch;
• and
• a power converter circuit coupled to the common node of the solid-state AC switch and configured to convert an AC voltage to a direct current (DC) voltage, wherein the common node of the solid-state AC switch is utilized as a DC ground node of the power converter circuit, and wherein the DC voltage output from the power converter circuit is ground referenced to the common node of the solid-state AC switch;
• wherein the power converter circuit is configured to convert the AC voltage to the DC voltage by utilizing current drawn from AC supply power to charge a storage capacitor to a maximum DC voltage;
• and
• wherein the power converter circuit comprises a peak voltage detection circuit which is configured to monitor the voltage across the storage capacitor and (i) generate a control signal to terminate a charging operation when the voltage across the storage capacitor is determined to reach the maximum DC voltage, and to generate a control signal to initiate a charging operation to recharge the storage capacitor when the voltage across the storage capacitor is determined to drop below a minimum threshold DC voltage.

A power converter circuit, comprising:

• a first terminal and a second terminal configured to couple to an alternating current (AC) power source which provides AC power;
• a storage capacitor coupled to and between an output node of the power converter circuit and a direct current (DC) ground node;
• a first solid-state switch disposed in an electrical path between the second terminal and the output node;
• and
• control circuitry configured to control an operation of the first solid-state switch for sourcing a charging current from the AC power, which flows from the second terminal to the output node, to charge the storage capacitor and generate a DC voltage at the output node, wherein the control circuitry is configured to:
• monitor a DC voltage at the output node;
• determine an occurrence of a transition to a negative half-cycle of the AC power;
• and
• in response to determining the occurrence of the transition to the negative half-cycle of the AC power:
• cause the first solid-state switch to be deactivated to disable the sourcing of the charging current to the output node, in response to determining that the monitored DC voltage at the output node is at a maximum DC voltage or greater than a minimum DC voltage;
• and
• cause the first solid-state switch to be activated to enable the sourcing of the charging current to the output node to charge the storage capacitor to the maximum DC voltage, in response to determining that the monitored DC voltage at the output node is at or below the minimum DC voltage.