MODERN PROTECTION AND CONTROL EQUIPMENTS USED IN SHP PLANTS

Abstract

Protection and control equipments are very important in power plant operation. Throughout the history of the power system protection and control, improvements have continuously been made to all aspects of protection and control equipment. In this dissertation work, though the systems considered are not very much advanced, but they are new, technically 'good and economically viable for the small hydropower plant operation In this dissertation work, the small hydropower plant model is simulated to study the behaviour in normal and abnormal conditions. The MATLAB SIMULINK software is used to simulate this model. The whole model considered is turbine generator unit connected to network through delta/Y transformer including the control systems like PID governor and IEEE type 1 excitation system. This whole model is simulated when the unit is subjected to three-phase fault. Another DCIA type. excitation model is developed and the results are compared with the above model. As a case study, specifications of Gangotri hydropower plant are taken and the results are verified with. This model is useful to simulate the behaviour of grid connected small hydropower. plant subjected to three-phase fault. Inverse-time characteristics have been drawn for the microprocessor-based overcurrent relays, which are implemented according to the analytical equation given in [12] using a program developed in MATLAB. Test data for two models of relays, which are given by IEEE working committee, are verified with the above program. The data for third model is proposed to get the better iii performance results than first two models. If the relay is developed with this data, better results can be obtained within the conformance band limit. iv