SHORT-TERM GENERATION SCHEDULING OF THERMAL UNITS WITH VOLTAGE SECURITY AND ENVIRONMENTAL CONSTRAINTS

A dynamic and linear programming-based approach is investigated for th e short-term generation scheduling of thermal units considering the se curity and environmental constraints of electric power systems. In add ition to the basic constraints (i.e. real power limits of the generato rs, real power demand, spinning reserve, minimum up and down time of u nits) a comprehensive set of constraints is considered including: tran smission line capacity limits, generators dynamic ramp rate, voltage s ecurity margin and environmental issues. An optimal multiplier continu ation method is adopted to effectively calculate the voltage security margin. The constraint relating to the voltage security margin is cons idered as a transition constraint in the dynamic programming process. The environmental issue is considered as a restriction on the hourly S O2 emission allowances and other constraints are considered in the dyn amic/linear programming procedures. Results of the application of the proposed algorithm to a test system are presented to illustrate the ef fectiveness of the approach.