Power parallel operation control method based on Modulated Phase Tracking

A novel parallel operation control scheme - Modulated Phase Tracking Method (MPTM) is put forward. In MPTM each paralleled inverter modulates its power value into the phase of a periodic pulse signal and transmits it to the communication line. By phase-locked technique, all the inverters track the pulse-leading inverter which has the maximal output power value. When the output pulses of inverters are synchronized, the output power values are all the same. This method has high precision and good stability. It realized the democratic master-slave logic with high control redundancy. The detection and regulation resolution of voltage frequency is less than 5×10-6Hz and 2×10-5Hz respectively. The experimental results show the proposed method greatly improved the current-sharing precision and the adjusting speed.