抄録
The idea of 2nd-order delta-sigma modulated inverter is applied to the control of parallel-connected multiple voltage-source PWM inverters and single-phase PWM inverter bridges. A single 2nd-order integral feedback controller (PI-I controller) accommodates all the unit inverters or the half bridges in the system. The control is expected to take full advantage of the switching bandwidth increased by the multiplication of unit inverters, as the loop-gain, which governs the contorl performances such as disturbance rejection, is roughly proportional to the squared band-width. The synchronization condition for the output multi-level PWM pulse to triangular carrier signals is derived and tested. The suppressing ability of disturbances is compared with a current-feedback system. The characteristics of the control are tested in an experimental study.
