Modeling of Series Static Voltage Restorer (SSVR) in Distribution Systems Load Flow

This paper presents modeling of series static voltage restorer (SSVR) in load flow calculations for steady-state voltage compensation. An accurate model for SSVR is derived to use in load flow calculations. The rating of this device as well as direction of required reactive power injection to compensate voltage to the desired value (1
^p.u.
) is derived and discussed analytically and mathematically using phasor diagram method. Since performance of SSVR varies when it reaches to its maximum capacity, modeling of SSVR in its maximum rating of reactive power injection is derived. The validity of the proposed model is examined using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of SSVR for under voltage problem mitigation in the distribution networks is determined. The results show the validity of the proposed model for SSVR in large distribution systems.