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To insure reliability in electrical networks, loads are supplied by more than one source. In this paper a transfer scheme using two Static Transfer Switches (STS) located remotely is presented for transferring the feeder load to an alternate source that is out of phase from the primary (preferred source). The objective is to have a minimum disruption to the feeder voltage in terms of the dead time for transfer appearing as notches in the voltage waveform. The new proposed transfer method requires only a minimum communication between the two STS units in order to achieve synchronization. Different case studies of transferring power in a typical network while two sources having a phase difference are simulated and presented in this paper using MATLAB/SIMULINK.

Medium-Voltage capacitor banks are widely used in distribution network applications such as power-factor correction, reducing energy consumption and power losses. However, using a switched capacitor bank can generate excessive transients to the electrical system. In this paper, the transients following the energization and de-energization of a capacitor bank are obtained using frequency dependent models of the distribution network. Furthermore, a detailed breaker model is employed to enhance the accuracy of the results since the effects of restrikes or prestrikes can wear the contacts of breaker leading to failure. Finally, a recently proposed diode based transient limiter is modeled to study its effectiveness on limiting the switching transients and its ability in eliminating risk of failure in the bank and its associated circuit breaker.