Abstract
This paper demonstrates the use of dual variables associated with power equality constraints in Volt/VAR optimization models as a loss locational sensitivity. The dual variables can be employed for optimal placement of VAR compensation equipment and distributed energy resources (DERs). In addition, it can be utilized to price DERs generated power. The concept is illustrated thoroughly and tested on a modified IEEE-69 bus distribution system and results are presented and discussed. A comprehensive nonlinear programming formulation of distribution system Volt/VAR optimization model is illustrated. Furthermore, a penalty-based approach that handle discrete or integer variables and solve MINLP as continuous NLP is reviewed and validated. The presented formulation is able to directly allocate the dual variables values.