Two Control Schemes to Control Flow of Current Using Series Connected PWM-Voltage-Sourced Converter

In this paper, two control schemes are proposed to control the line current using series connected PWM-Voltage-Sourced Converter (PWM-VSC). The series connected PWM-VSC injects a balanced set of three phase controllable voltages which lags or leads the current by 90°, thus it can emulate a capacitor or inductor. Therefore, it can alter the equivalent impedance of the transmission line and consequently the transmitted power and line current. There are two methods to control the voltage of the VSC: (1) by controlling the magnitude of the VSC voltage and (2) by controlling the phase angle of the VSC. In this paper, two control schemes are designed and tested using MATLAB/SIMULINK. Time domain simulations show the capability of the series-connected PWM-VSC, with both control schemes, to control the line current