Patent ID: 7688042

Claim:
A power factor correction apparatus for correcting a power factor of transmission lines, the power factor correction apparatus comprising: a switch electrically connected to the transmission lines; a compensator electrically connected to the switch for compensating the power factor; a detecting apparatus electrically connected to the transmission lines for detecting voltages transmitted in the transmission lines; and a voltage processing circuit electrically connected to the detecting apparatus and the switch, the voltage processing circuit comprising: a voltage comparison unit comprising an operational amplifier electrically connected to the detecting apparatus for comparing the voltages with each other to generate a voltage; and a time-delay unit electrically connected to the voltage comparison unit and the switch for delaying the voltage; wherein the detecting apparatus comprises a current detect circuit electrically connected to a noninverting input of the operational amplifier via a resistor, and a voltage detect circuit electrically connected to an inverting input of the operational amplifier via a resistor and a variable resistor.