List of Articles Power system protectionovercurrent relaycoordinationrelay characteristicIHSS algorithmPickup currentstime setting multiplier Open Access Article Abstract Page Full-Text 1 - Overcurrent Relay Coordination Using Improved Hyper-Spherical Search Algorithm Considering Different Relay Characteristics and Pickup Current A. Hassani Ahangar H. Nafisi H. Karami G. Gharehpetian