Patent ID: 8482885

Claim:
A hybrid switch circuit for coupling an AC power supply to a load, comprising: a hybrid switch coupling an input conductor configured to be connected to the AC power supply to an output conductor configured to be connected to the load, the hybrid switch comprising: a power semiconductor switchable between on and off states in accordance with a power semiconductor control current, wherein, in the on state, the power semiconductor provides a conductive path for an AC current from the AC power supply between the input and output conductors and, in the off state, the conductive path provided by the power semiconductor is opened; and a relay having contacts in a conductive bypass path connected in parallel with the power semiconductor, the contacts being controllable between open and closed states in accordance with a relay control current taken from an output terminal of the power semiconductor, wherein, in the closed state, the relay provides a conductive bypass path between the input and output conductors that bypasses the power semiconductor; and a control circuit configured to switch the hybrid switch from a non-conductive state to a conductive state by switching the power semiconductor into the on state in response to flow of the power semiconductor control current and subsequently closing the relay in response to flow of the relay control current.