Vol.:(0123456789) 1 3 Journal of Electrical Engineering & Technology https://doi.org/10.1007/s42835-020-00593-5 ORIGINAL ARTICLE Simultaneous Reconfiguration and Optimal Capacitor Placement Using Adaptive Whale Optimization Algorithm for Radial Distribution System M. Ramesh Babu 1  · C. Venkatesh Kumar 1  · S. Anitha 2 Received: 23 April 2020 / Revised: 30 July 2020 / Accepted: 19 October 2020 © The Korean Institute of Electrical Engineers 2020 Abstract The losses in the distribution networks due to the line resistance decrease the overall efficiency of the power distribution. Reducing the power losses and regulating the voltages within the limits are necessary to provide quality power to the consum- ers. The power loss can be minimized by optimum network reconfiguration and the placement of the capacitors. Considering independent network reconfiguration and placement of the capacitor is not effective during heavy loading conditions. This paper proposes a simultaneous network reconfiguration and capacitor placement in radial distribution network to minimize the real power losses, operating cost and to improve the bus voltages. The Johnson’s algorithm is used to find the minimal spanning tree during the network reconfiguration and an adaptive whale optimization algorithm is used as an optimization method. The proposed methodology is tested on standard IEEE 33-bus and 69-bus radial distribution systems. The effective- ness of the proposed method is validated by comparing the results with previous result reported in the literature in terms of cost saving and loss reduction. Keywords Adaptive whale algorithm · Network reconfiguration · Johnson’s algorithm · Optimal capacitor placement · Power loss reduction · Operating cost minimization List of Symbols P i Real power at sending node P j Real power at receiving node Q i Reactive power at sending node Q j Reactive power at receiving node P Li Real power load at sending node Q Li Reactive power load at sending node P Lj Real power load at receiving node Q Lj Real power load at sending node R ij Resistance between i and j X ij Reactance between j and j + 1 V i Sending end voltage V j Receiving end voltage V min / V max Min/max voltage limits P loss Real power loss between i and j P Tloss Total real power loss K p Cost per kWh D Depreciation factor K 1 Cost per installation CB Number of compensated bus K c Cost per kvar Q ci Value of installed reactive power 1 Introduction The reliable power delivered to the consumers depends upon the efficiency of the distribution system. The ratio between resistance and reactance is high for distribution lines due to shorter length, which results in huge real power loss. It is necessary to minimize the real power losses in the distribu- tion network to ensure optimal and efficient power distribu- tion. A variety of methods have been proposed to minimize * M. Ramesh Babu rameshbabum@stjosephs.ac.in C. Venkatesh Kumar venkateshceg@gmail.com S. Anitha aniselva23@gmail.com 1 Department of Electrical and Electronics Engineering, St Joseph’s College of Engineering, Sholinganallur, OMR, Chennai, Tamil Nadu 600119, India 2 Department of Electrical and Electronics Engineering, IFET College of Engineering, Viluppuram, Tamil Nadu 605602, India