ENHANCEMENT OF INTERFACE FLOW LIMITS IN TERMS OF VOLTAGE STABILITY WITH REACTIVE RESERVE BASED CONTINGENCY CONSTRAINED OPTIMAL POWER FLOW

This paper presents a concept of reactive re- serve based contingency constrained optimal power flow (RCCOPF). RCCOPF for enhancement of interface flow limit is composed of two modules, which are the modified continuation power flow (MCPF) and reactive optimal power flow (ROPF). In RCCOPF, two modules are re- peatedly performed to increase interface flow margins of selected contingent states until satisfying the required enhancement of interface flow limit. In numerical simula- tion, a simple example with New England 39-bus test system is shown. tion of researchers. In this paper, OPF formulations with reactive reserve constraints are discussed. In (4), OPF formulations with reactive reserve constraints are pro- posed for preventive and corrective control considering voltage security. However, details for developing reac- tive reserve constraints are not included. In (5), dis- patching formulations with reactive reserve constraints are presented. Reactive reserve constraints are based on reactive reserve basin of voltage control area. However, voltage control area can be changed as transmission systems evolve and severe contingencies occur. In this paper, reactive reserve based contingency constrained optimal power flow (RCCOPF) is presented. RCCOPF consists of two modules, MCPF and ROPF. ROPF for- mulation has reactive reserve constraints to enhance interface flow margins in post-contingent states. With concept of reactive reserve evaluation presented in (6), these constraints are decided in the process of MCPF for determining interface flow margins. In RCCOPF, two modules are repeatedly performed until satisfying the required enhancement of interface flow limit. In case study, an illustrative example with New England 39-bus test system is shown.