Absh.act-This paper investigates impacts of energization transients of large shunt reactors on the operation of W A C and HVDUAC power systems. The Electromagnetic Transients Program for DC systems (EMTDC) is used for the simulation studies. The studies conclude that shunt reactor energization can result in undesirable response of power system apparatus and even interruption of power flow, e.g. commutation failure of HVDC converters. The studies also indicate that the energization transients can be adequately alleviated based on the use of preinsertion resistor and/or controlled energization strategies.