The invention discloses an output
current wave shape control method for a triphase
Active Power Filter (APF). A T-shaped filter and a
current wave shape controller are adopted to control the output
current wave shape of the triphase AFT. The output filter for each
phrase bridge arm of an
inverter is a capacity connected to the middle point of two inductances connected with each other in series, and form a T-shaped structure, namely T-shaped filter; the calculation method for
wave shape controlling is conducting Alfa, Beta, Omicron transformations to instruction current of the triphase APF, actual output current and the
voltage of the power network, so as to realize decoupling of the
wave shape controlling of the abc triphase output current; and respectively conducting pole assignment to the single-
phrase system under decoupled Alfa, Beta, Omicron
axis system, and correcting the error between the APF actual output current an the instruction current, so as to get instruction
voltage of each
phrase under the alfa, beta, Omicron
axis system; and at last sending the instruction
voltage to a
space vector modulating module, so as to confirm the on-off
signal of each bridge arm switch tube, thereby causing the actual output current of the PFA to accurately track the instruction current.