In order to accurately describe generator output limits considering operation prohibited zones

“AND” and “OR” logic relationships between optimization constraints are analyzed. A mixed logic constrained optimization (MLCO) problem including both “AND” and “OR” logic constraints is studied

based on which

the generator output limitations considering operation prohibited zones are expressed as a set of constraints with “OR” logic relationship. And the MLCO model of environmentally economical dispatch is developed. According to the ideas of the Boolean algebra logic transformation

the equivalent mathematical transformation of the constraint logical relationship is derived

and the transformation between “OR” and “AND” logic constraints is implemented. Thus the MLCO problem is converted to a conventional nonlinear optimization problem with “OR” logical constraints only

which can be solved by the interior-point method. The test results of a 6-unit and 15-unit system show the validity of the MLCO model and method proposed

and their high solving accuracy and efficiency. This work is supported by Guangxi Youth Fund (No. 2014GXNSFBA118277) and Science and Technology Development of Nanning (No. 20121025).