Guía para el ajuste de las protecciones eléctricas de sistemas DC : Guía para el ajuste de la protección de sobrecorriente de fallas a tierra y de la protección de sobrevoltaje de la linea DC de un sistema HVDC.

Abstract

In this degree work has a topic that is not generally considered in traditional electrical protection course, such as DC protections. For this, High Voltage Direct Current (HVDC) transmission system is considered, which is increasingly common in modern power systems, due to its evolution and improvement that has gone hand in hand with power electronics. For analysis, the system typically used in these studies is considered, which corresponds to the CIGRE HVDC Benchmark model. Protections that are analyzed in this work are the overcurrent protections of ground faults and overvoltage, all this form the DC side of the system. These systems are not in common use, so there are proposals for protection schemes and adjustments, where some criteria based on experiences are considered. As indicated in the technical literature to identify and isolate ground faults in this type of system, it can be done by means of control action or protection schemes, such as converter blocking, through an AC breaker and DC breaker. For this work, which is based on analysis by simulation. Protection scheme used is through the AC breaker. For overvoltage protection, setting is considered based on a maximum voltage that elements of the system can withstand. Causes that produce overvoltage in the DC transmission line are load shedding or broken conductor, for the simulation, the latter case is analyzed.