Combinational Linear Programming Approach for Daily Optimal Operation of Customers with DG/ESS under TOU Pricing for Customer EMS Software Applications

Fast calculation under limited computation resources is a basic requirement for a customer energy management system. After discussion of several existing models for optimal operation of customers with DG and ESS, a novel optimization model is presented. A possible energy storage system with binary states of charge/discharge is developed according to a sectionalized time-of-use pricing structure, followed by the derivation of the binary state of power flow direction at the point of common connection with the power grid concerned. The number of such comprehensive state combinations is not large, and in case that those state decisions are known, the daily optimal operation of a customer with DG and ESS can be formulated as a linear dynamic system. Therefore it can be solved by a global optimal promised linear programming. Different types of customers with different DG daily generation curves are employed as case studies to demonstrate the high computation efficiency with less computation resources for customer EMS application.