Patent ID: 8772969

Claim:
A static transfer switch, comprising: a first contact switch configured to be turned on or off according to a first driving signal to supply output power of a first power source to a load; a first semiconductor switch configured to be connected in parallel to the first contact switch, and configured to be turned on or off according to a first gate signal to supply the output power of the first power source to the load when the first contact switch is turned off; a second contact switch configured to be turned on or off according to a second driving signal to supply output power of a second power source to the load; a second semiconductor switch configured to be connected in parallel to the second contact switch, and configured to be turned on or off according to a second gate signal to supply the output power of the second power source to the load when the second contact switch is turned off; a control unit configured to generate the first and second driving signals and the first and second gate signals; a contact point sensing unit configured to sense whether each contact switch is electrically turned off and to output a contact point sense signal; a state detecting unit configured to sense whether each switch is turned off according to output power of the each switch and the contact point sense signal transmitted from the contact point sensing unit, and to output a state signal; and a switching command unit configured to command to switch a power supply path to the load according to the state signal outputted from the state detecting unit, wherein the control unit simultaneously generates the first driving signal and the first gate signal together, and simultaneously transmits the first driving signal and the first gate signal together to the first contact switch and the first semiconductor switch, and wherein the control unit simultaneously generates the second driving signal and the second gate signal together, and simultaneously transmits the second driving signal and the second gate signal together to the second contact switch and the second semiconductor switch.