Abstract
A high performance voltage detection and PLL system suitable for single-phase inverters such as UPS will be proposed. The single-phase utility voltage is transformed to a pseudo three-phase voltage, and this three-phase voltage is used for the voltage detection and the phase detection. The time delay of the circuit to obtain the three-phase signal is only 4.6 msec (in case of 60Hz), therefore this method can be used for three-phase SVG to reduce the influence of unbalanced system voltage disturbances such as 2LS.
