Nitsenko V. Improving performance operation of busbar relay protection of switchgears

The purpose of the dissertation work is to increase the reliability, selectivity and sensitivity of the relay protection of the prefabricated bus networks of the distribution plants of electric stations and networks. The object of the research is electromagnetic and electromechanical transients in electric power systems. The object of the research is the parameters of differential-phase protection of prefabricated busbars of distribution installations of objects of electric power systems. The scientific novelty of the obtained results is as follows: for the first time mathematical dependences of the change of current and angle errors of transformers current for operating modes outside the normalized values ​​of these errors and it is established that current errors in emergency modes change it is much more than the angle that allowed us to substantiate the expediency of using the differential-phase protection of the tires and to determine that this type of their relay protection has a high sensitivity regardless of the amplitude values ​​of emergency currents for internal short circuits, the method of differential-phase protection of tires is improved, which is different , that the algorithm for comparison of phase currents is applied as the only means of providing absolutely selective action of relay protection of tires, it allows to increase its sensitivity and reliability ies in emergency mode and introduce a group of non-branded security configuration settings of parameters; The mathematical model of differential-phase protection of tires is improved, which is characterized by the fact that the comparison of phase currents is carried out by determining the duration of the interval of coincidence of voltage logic impulses; this allows to provide high sensitivity of protection in the minimum emergency modes without the use of a high-sensitivity current body, to increase the reliability of protection to trigger damage prefabricated tires and reliability for non-breakdown in the absence of their damage.