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The reliable design, planning, and operation of power systems are of paramount importance for providing reliable services to customers. This article reviews the different aspects of power system reliability, ranging from planning to operation. Standard benchmarks employed for power system studies are reviewed according to nearly 2,500 IEEE journal papers from 1986 to early 2019. Our overview provides the pros and cons of existing test systems, implying the lack of appropriate benchmarks for future power system studies, including renewable resources and modern technologies. Furthermore, this article presents requirements for updating and modifying the benchmarks for modern power systems... 

Power systems have been undergoing significant restructuring as a result of increasing independently operated local resources. Consequently, new entities, i.e. microgrids (MGs), are developed, which facilitate the integration of local resources, specifically renewable energy sources (RESs), into the operation of power systems. Despite many benefits, the integration of RESs could cause severe rampings in the net-load, which would challenge the reliable operation of the system. Therefore, it seems essential that flexible local resources in an MG should be employed to provide flexibility services to the main grid, thus ensuring that ramping in the MG's net-load would meet the ramping capability... 

Management of reactive power resources is vital for stable and secure operation of power systems in the view point of voltage stability. This paper deals with the management of on-load tap changers (OLTCs) and dynamic VAR sources (including synchronous generators, synchronous condensers, and shunt reactive power compensators) to improve voltage stability margin (VSM) of power systems. This problem is usually called optimal reactive power dispatch (ORD) in the literature. The main contribution of the paper is to introduce a new objective function for the ORD problem. The proposed objective function is derived based on a local voltage stability index, called DSY, and has a strong correlation... 

The introduction of microgrids (MGs) and renewable energy sources (RESs) has caused significant shifts in the operation of power systems. Despite many benefits, integration of RESs has emerged new issues in the power systems operation. One of the issues recently raised by some utilities, is the severe ramps which are seen in systems with high penetration of RES. On the other hand, the traditional flexible power plants could not provide the ramp required in these systems. As a result, flexible local resources in independent entities like MGs should be employed to tackle this issue in these systems. In this paper, a novel model is developed to investigate the effects of MGs and gas grid... 

This paper develops a model for nonlinear three-phase inductors with magnetic coupling between phases along with saturation characteristics for each phase. It can be used in modelling reactors and/or transformers for resonance and ferroresonance studies in non-symmetrical operation of power systems. While three phase modelling of reactors and transformers in non-symmetrical analyses play vital role; currently, time domain simulation packages provide either “detailed saturation model for three phase inductors without magnetic coupling” or “three phase inductors with magnetic coupling without saturation characteristics”. The proposed model adds a set of controllable linear coupled inductance,...