[Q.sub.PQE] (*)--input-output diagram of the extraction turbine;
[P.sub.PQE] (*)--cogeneration part of the power output of the extraction turbine;
[Q.sub.QE]--heat load (output) of the extraction turbine;
[P.sub.PQ]--total power generation output of the CPP with the extraction turbine.
Cogeneration Power Plant: Boilers & Extraction Turbines & Generators (PQ Unit)
The input-output characteristics of cogeneration power plants (CPP) with the extraction turbines can be presented as follows:
4) constraints of CPP with extraction turbines (k = 1, ..., n3)
Here [P.sub.D] is the electric power demand; [Q.sub.D] is the heat demand; i, j, k, l are the indices and n1, n2, n3, n4 are the numbers of the condensing power plants, boiler plants, CPP with extraction turbines and CPP with back-pressure turbines, respectively.
3) for cogeneration units with extraction turbines (k = 1, ..., n3)