Voltage Source Inverter Based Static Synchronous Series Compensator f or Improved Available Transmission Capability in a Transmission Line

Abstract

This paper deals with the active power flow control in a transmission line thus improving Available Transmission Capability (ATC) using Static Synchronous Series Compensator (SSSC). For the analysis, a generator supplying two parallel transmission lines connected to a load as 2-bus system is considered. When the load increases, active power flow in the transmission lines is shared based on their limits depending on ATC which is based on power handling capacity according to the demand. Therefore, for effective control of the active power flow considering the power handling capacity, SSSC is connected in series with one of the transmission lines. SSSC controls the active power flow in transmission line by injecting voltage in quadrature to the line current. SSSC designed in this work is a Voltage Source Inverter (VSI) which provides pulses and would help to inject the required voltage in quadrature to the line current. The PWM pulses of the VSI based SSSC is generated by dsPIC microcontroller. SSSC is modeled under both MATLAB / Simulink environment and implemented on a scaled down model of 150 km, 15.6 mH transmission lines connected in between generator and load.