Multi-objective linearised optimal reactive power dispatch of wind-integrated transmission networks

Abstract

This study develops a multi-objective approach to pursue an optimal reactive power dispatch (ORPD) of power systems equipped with wind farm (WF) integrations. The preliminary control variables include shunt compensators, synchronous condensers, and under-load tap changers (ULTCs). Innovatively, reactive power provision capability of WFs, beyond their active power contributions, is scheduled besides the variables above. Seemingly, a double operating area is adopted for WF within which it injects active power towards the main grid. Concurrently, it could inject or absorb reactive power, which impacts technical metrics of the power system operation. The main purpose is then establishing a compromise between the power loss and voltage deviation minimisation and also reducing the number of ULTC tap variations and operations. To handle the multiobjective feature of the proposed model, the global criterion method is deployed. The established ORPD model represents a multi-objective non-linear mathematical problem, which is converted to a mixed-integer linear programming format. By this way, the computational burden of the problem is reduced to maintain an acceptable accuracy of the obtained results. Detailed discussions are provided to assess the performance of the proposed model.