Experiences on assessing Alberta power system voltage stability with respect to the WSCC reactive power criteria

This paper reports experiences on voltage stability assessment for the Alberta interconnected power system with respect to the WSCC criteria. The WSCC criteria are first reviewed. The system transfer capability is then assessed under normal operating conditions and with credible contingencies. Modal analysis is performed on critical contingencies to identify their impacts and associated voltage collapse areas. The paper demonstrates a practical engineering approach to assess the voltage stability and reactive power reserve conditions of a real power system. In addition, methods for identifying critical voltage collapse mode and to measure the severity of contingencies are proposed.