Emergency control schemes for securing the South-East Australian power system

In 1990 the South Australian power system (1.8 GW) was connected to the interconnected New South Wales-Victorian power system (15.5 GW). The interconnection was designed on an opportunity interchange basis for power transfer levels of 500 MW into South Australia and 250 MW out of South Australia. The extensive use of double circuit transmission to minimise costs required that high speed automatic control action be taken to secure operation of the system for credible system contingencies. The authors explain the investigation undertaken to define the problems and the possible solutions. The design philosophy for emergency control systems is fully explained, with emphasis on the measures used to ensure reliable and secure operation of the schemes