In this paper

distributed power flow controller (DPFC) constraints are analyzed. The energy balance relationship between fundamental wave and third harmonic in series and shunt-side converter is deduced. A proportional integral (PI) controller of the DPFC is constructed. The PI controller uses the voltage amplitude and phase angle injected into the system in the series side

along with the modulation ratio of the three-phase converter on the shunt side as the control variables. A multiobjective coordinated control equation is proposed

which factors the constraints of the energy balance between series and shunt side

device capacity limit

safe operation limit

fundamental component

as well as third harmonic component of the injection voltage at the series side. The equation minimizes the variance between the actual value of the control target and its given value to ensure that the DC capacitor voltage

both in the series and shunt side

is stable at target value. Simulations are conducted to verify correctness and effectiveness of the proposed control method.